Ana Paula Rocha da Cos a Dias
In luence o he modi ica ion o
asphal mix u es on hei beha iou
a low empe a u es
Janua y 2020
Ana Paula Rocha da Cos a Dias
In luence o he modi ica ion o
asphal mix u es on hei beha iou
a low empe a u es
Disse ação de Mes ado
Mes ado In eg ado em Engenha ia Ci il
T abalho e e uado sob a o ien ação do
Dou o Hugo Manuel Ribei o Dias da Sil a
Janua y 2020
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
ii
DIREITOS DE AUTOR E CONDIÇÕES DE UTILIZAÇÃO DO TRABALHO POR TERCEIROS
Es e é um abalho académico que pode se u ilizado po e cei os desde que espei adas as eg as e
boas p á icas in e nacionalmen e acei es, no que conce ne aos di ei os de au o e di ei os conexos.
Assim, o p esen e abalho pode se u ilizado nos e mos p e is os na licença abaixo indicada.
Caso o u ilizado necessi e de pe missão pa a pode aze um uso do abalho em condições não p e is as
no licenciamen o indicado, de e á con ac a o au o , a a és do Reposi ó iUM da Uni e sidade do Minho.
Licença concedida aos u ilizado es des e abalho
A ibuição-NãoCome cial
CC BY-NC
h ps://c ea i ecommons.o g/licenses/by-nc/4.0/
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
iii
ACKNOWLEDGEMENTS
I would like o hank and dedica e his disse a ion o he people men ioned in he nex pa ag aphs.
To my pa en s, o all he suppo and lo e ha b ough me o his poin in my li e.
To my ad iso , P o esso Hugo Sil a, o his expe ise, help, and guidance du ing his inal s ep o
g adua ion, o always going ha ex a mile o assis hose who need and being a g ea inspi a ion o me,
e en be o e his disse a ion.
To Eng. Ca los Palha, o all he knowledge you o e ed me, o always ying o do you bes o esol e
e e y si ua ion ha a ises, and o he iendship we de eloped.
To Hélde , o all you help h oughou his esea ch and he un momen s
“pa ece ácil”
.
To he Weedswes Global Solu ions G oup, o p o iding he ma e ials ha made his esea ch possible.
To e e yone I me in he labo a o y, iends, colleagues, echnicians, eache s, oo many o name. You all
made i eel like a second home, e en equipped wi h i s own “ oom o knowledge”, I am going o miss i ,
and you all.
To my iends, o he momen s o un, and especially o
ma ianos
.
To Daniel, o all he mo i a ion you ga e me, all he pa ience and ou inc edible con e sa ions; au hen ic
connec ions a e a e, bu soul ebels always ind each o he .
Finally, o he pe sons ha indi ec ly con ibu ed as a sou ce o inspi a ion and suppo , o he new
expe iences and cons an lea ning, you oo played you pa in his achie emen .
Thank you all.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
i
STATEMENT OF INTEGRITY
I he eby decla e ha ing conduc ed his academic wo k wi h in eg i y. I con i m ha I ha e no used
plagia ism o any o m o undue use o in o ma ion o alsi ica ion o esul s along he p ocess leading o
i s elabo a ion.
I u he decla e ha I ha e ully acknowledged he Code o E hical Conduc o he Uni e si y o Minho.

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
In luência da modi icação de mis u as be uminosas no seu compo amen o a baixas
empe a u as
RESUMO
Os egulamen os nacionais êm sido subs i uídos po egulamen os eu opeus nos á ios países da
comunidade eu opeia. Es a p og essi a uni o mização das no mas eu opeias exige que as emp esas
nacionais subme am os seus p odu os a ensaios pad onizados na Eu opa, mas pe mi e melho a os
p odu os pa a esponde à p ocu a de no os me cados, expandindo o comé cio das emp esas. Nes e
con ex o, as emp esas po uguesas podem di e si ica o seu po ólio e in es i em p odu os des inados
a egiões mais ias, que em ge al são mais p óspe as. No en an o, es as egiões êm um clima mui o
di e en e da ealidade nacional, com in e nos mais ios e longos, pa a o qual há pouca expe iência.
Quando as empe a u as descem pa a ní eis mui o baixos, os pa imen os são subme idos a ensão
é mica e podem ap esen a á ias deg adações, como endilhamen o é mico. Nes es casos, podem se
usados políme os pa a modi ica o be ume e melho a algumas das suas p op iedades, como a
ecupe ação elás ica, coesão e duc ilidade. Os políme os ambém eduz alguns dos p oblemas das
mis u as be uminosas, como o endillhamen o é mico e po adiga e a de o mação pe manen e.
O obje i o des e abalho oi es uda o compo amen o das mis u as be uminosas a baixas empe a u as,
em pa icula quando se u ilizam be umes modi icados. Assim, o am selecionados e ensaiados ês
ligan es nes e es udo: um be ume con encional com pene ação 50/70 e dois be umes modi icados com
políme os (PMB) ob idos pela adição de 2,5% e 5,0% de SBS, espe i amen e, ao be ume 50/70. Em
seguida, os PMB o am en ão inco po ados em mis u as do ipo SMA 11, que o am subme idas a
ensaios mecânicos a baixas empe a u as com base na no ma eu opeia EN 12697-46. Os ma e iais e os
mé odos u ilizados se i am pa a se de ini quais as melho es al e na i as u u as pa a climas ios.
Algumas das p op iedades dos ligan es e das mis u as be uminosas que o am a aliadas o am a
esis ência ao endilhamen o é mico, luência, ecupe ação elás ica, o ça coesi a e duc ilidade.
Em ge al, concluiu-se que as mis u as be uminosas a aliadas nes e abalho i e am um desempenho
adequado a baixas empe a u as, em pa icula as p oduzidas com PMB. O conhecimen o dos ensaios
de labo a ó io a baixas empe a u as (EN 12697-46) e suas conclusões ine en es ajuda ão a desen ol e
no as soluções de pa imen ação pa a as zonas climá icas mais ias.
Pala as-cha e:
Baixas Tempe a u as; Be ume Modi icado com Políme os (PMB); Es i eno-Bu adieno-Es i eno (SBS);
S one Mas ic Asphal
(SMA); No ma Eu opeia; Desempenho das Mis u as Be uminosas.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
i
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
ABSTRACT
The na ional egula ions ha e been eplaced by Eu opean egula ions in he se e al coun ies o he
Eu opean Communi y. This p og essi e uni o misa ion o Eu opean s anda ds equi e he na ional
companies o submi hei p oduc s o s anda dised es s alida ed in Eu ope, bu enables he
de elopmen o imp o ed p oduc s o mee he demand o new ma ke s, hus expanding business ade.
In his con ex , Po uguese companies can di e si y hei po olio and in es in p oduc s aimed a colde
egions, which in gene al a e mo e p ospe ous. Howe e , hese egions ha e a clima e di e en om he
na ional eali y, wi h colde and longe win e s, in which ou companies ha e li le expe ience. When
empe a u es d op o signi ican ly low le els, pa emen s a e subjec ed o he mal s ess and can p esen
se e al dis esses, such as he mal c acking. In hese si ua ions, polyme s can be used as modi ie s in
asphal binde s o imp o e hei p ope ies, such as elas ic eco e y, cohesion and duc ili y. Polyme s
also minimize some o he p oblems o asphal mix u es, such as he mal and a igue c acking and
pe manen de o ma ion.
The objec i e o his wo k was o s udy he beha iou o asphal mix u es a low empe a u es, in pa icula
when using modi ied bi umens. Thus, h ee binde s we e selec ed and es ed in his s udy: a s anda d
50/70 pene a ion g ade bi umen, and wo polyme -modi ied binde s (PMB) ob ained adding 2.5% and
5.0% o SBS, espec i ely, o he 50/70 pen g ade bi umen. Then, he PMBs we e inco po a ed in o
SMA 11 mix u es, which we e subjec ed o low- empe a u e mechanical es s based on he Eu opean
S anda d EN 12697-46. The ma e ials and me hods used in his wo k we e applied o suppo he
de ini ion o he bes u u e al e na i es o cold clima es. Some o he p ope ies o he asphal binde s
and mix u es e alua ed in his wo k we e he he mal c acking esis ance, c eep, elas ic eco e y,
cohesi e s eng h and duc ili y s eng h.
O e all, i is concluded ha he asphal mix u es p oduced and e alua ed in his wo k pe o med
adequa ely a low empe a u es, in pa icula hose wi h PMB. The knowledge ega ding labo a o y es s
a low- empe a u es (EN 12697-46) and hei de i ed conclusions will help o de elop new pa emen
solu ions o hose colde clima e zones.
Keywo ds:
Low- empe a u e; Polyme Modi ied Binde (PMB); S y ene-Bu adiene-S y ene (SBS); S one Mas ic
Asphal (SMA); Eu opean S anda d; Asphal Mix u e Pe o mance.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
ii
INDEX
1. INTRODUCTION ........................................................................................................... 1
1.1. Scope .................................................................................................................. 1
1.2. Objec i es and con ibu ions ............................................................................... 2
1.3. Disse a ion s uc u e ......................................................................................... 3
2. LITERATURE REVIEW ................................................................................................... 5
2.1. Asphal mix u es ................................................................................................. 5
2.2. Polyme s ........................................................................................................... 11
2.3. Bi umen ............................................................................................................. 17
2.4. Low- empe a u e condi ions .............................................................................. 24
3. MATERIALS AND METHODOLOGY .............................................................................. 27
3.1. Agg ega es ........................................................................................................ 27
3.2. Polyme ............................................................................................................. 30
3.3. Asphal binde s ................................................................................................. 30
3.4. Cha ac e iza ion o he asphal binde s ............................................................. 32
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
iii
3.5. Asphal mix u es ............................................................................................... 41
3.6. Mechanical me hods o cha ac e iza ion o he asphal mix u es ...................... 50
4. RESULTS AND ANALYSIS............................................................................................ 60
4.1. Analysis o he p ope ies o he agg ega e ....................................................... 60
4.2. Analysis o he asphal binde s .......................................................................... 62
4.3. Analysis o he asphal mix u es and specimens ................................................ 73
4.4. Mechanical pe o mance o he asphal mix u es .............................................. 77
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
1
1. INTRODUCTION
“Adap wha is use ul, ejec wha is useless, and add wha is speci ically you own.”
B uce Lee
1.1. Scope
T anspo in as uc u es a e subjec ed o a cons an e olu iona y p ocess, a consequence o he inc ease
in a ic, he a ia ion in he ype o a ic and he inc easing demand o sa e y, quali y, com o and
sus ainabili y s anda ds o i s pa emen s. The cycle o in e dependence be ween he e olu ion o
echnology and he e olu ion o he in as uc u e i sel is o g ea impo ance. The e olu ion o echnology
pe mi s he de elopmen and imp o emen o knowledge, echniques and ma e ials ha p oduce
oadways, which in u n makes hose cha ac e is ics e ol e and equi e new echnologies o allow o
hei imp o emen and consequen ly he c ea ion o new me hods and ma e ials.
Based on hese p emises and a se o es ablished knowledge, he scien i ic communi y decided o p o ide
a me hodological answe o hese cyclical needs. The e o e, speci ic p ocedu es, including s anda ds and
guidelines, we e es ablished o e alua e he ma e ials’ cha ac e is ics, and he p ocesses o be ollowed
o sampling, and labo a o y and “in si u” es ing.
In Po ugal, p e ious na ional egula ions ha e been, o will soon be, eplaced by Eu opean egula ions,
as in many o he coun ies o he Eu opean Communi y. This p og essi e eplacemen and consequen
uni o miza ion o s anda ds in se e al Eu opean coun ies allow hei na ional companies o be able o
subjec hei cu en p oduc s and se ices o his s anda diza ion, which is ecognized and alida ed by
he as majo i y o hese s a es. Besides, hose companies can now de elop new and imp o ed p oduc s
in o de o mee he demand o p e ious unexplo ed ma ke s and, hus, expand hei ade.
Addi ionally, Po uguese companies mus no be so dependen on he na ional cons uc ion ma ke and
i s economic luc ua ions and should di e si y hei p oduc po olio and in es in ypes o p oduc s aimed
a colde in e na ional egions. Those egions a e economically p ospe ous, in he case o No he n
Eu ope, o expanding ma ke s in de eloping economies, in he case o Cen al and Eas e n Eu ope. These
na ions ha e di e en clima es in compa ison o he na ional scena io, in which ou companies ha e li le
expe ience.

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
2
These clima e zones a e usually cha ac e ized by humid, long-las ing cold win e s in which he e is usually
hea y snow all and mild, humid summe s o he Scandina ia egion. Fo he Cen al and Eas e n
Eu opean egions, he clima e is usually explained by long cold win e s, wi h he signi ican p esence o
os and snow, and p edominan ly ho summe s (EC, 2019, Wo ldA las, 2019).
Du ing hese win e s, when empe a u es d op o signi ican ly low le els, he pa emen s a e subjec ed o
he mal s ess, and as a esul , c acking o he asphal laye s can occu . This c acking esul s om he
e ac ion o he pa emen gi en he empe a u es o which i is exposed. C acking can also occu as a
esul o he mal a igue o which oad su aces a e exposed in he al e na ing cycle o hea ing o cooling
while c acking by ex emely low- empe a u es is a p ima y p oblem in icy egions (Ala aş and Yilmaz,
2017). C acking due o he mal suscep ibili y a low empe a u es can addi ionally esul om he
e ac ion o binde s, which occu s when hei maximum ensile s eng h is eached. Open c acks allow
wa e o pene a e, which g adually eezes and expands and causes a pa ial des uc ion o he
bi uminous laye due o his olume ic expansion (Panga o a and Nikolo , 2016).
Polyme ic ma e ials can be used as addi i es in asphal mix u es so ha hei cha ac e is ics can be
imp o ed and hey can achie e be e pe o mance (Polacco
e al.
, 2008). Some he momechanical
p ope ies o asphal binde a ge ed in his wo k, such as elas ic eco e y, cohesion and duc ili y, a e
po en ially imp o ed by using polyme modi ied binde s (PMBs). PMBs can also minimize some o he
main p oblems o asphal mix u es, such as pe manen de o ma ion and c acking due o he mal
suscep ibili y and bi umen ageing (Fe nandes
e al.
, 2016).
The s esses ha occu in he bi uminous laye s de i ed om he empe a u e du ing cooling a e qui e
challenging o measu e di ec ly in he pa emen s uc u e. The e o e, he co ec analy ical es ima e is
c ucial, as well as he esul s ob ained h ough labo a o y es s. I is hen possible o compa e he
analy ical design wi h he empi ical esul s and calib a e and ec i y bo h (Pszczola
e al.
, 2019a).
1.2. Objec i es and con ibu ions
The main objec i e o his disse a ion is o e alua e he in luence o asphal binde and i s modi ica ion
in he low- empe a u e pe o mance o asphal mix u es. Ano he p ima y goal is o e i y he applicabili y
o labo a o y me hods and echniques o ob ain he p ope ies o hese mix u es a cold empe a u es.
These objec i es de i e mainly om an a emp o assess he in luence o he ype o asphal binde and
mix u e composi ion on he ensile s eng h p ope ies o asphal mix u es and s eng h ese e, as well
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
3
as he in luence o cooling a e on s eng h, elas ic eco e y and he beha iou o hese mix u es when
hey a e subjec ed o cyclic a igue s ess.
By analysing he adi ional ypes o asphal mix u es used gene ally in Eu opean egions wi h colde
clima es, as well as hei cha ac e is ics and beha iou a low empe a u es, he S one Mas ic Asphal
(SMA) mix u e was selec ed o his s udy as an excellen example o hose mix u es. Mo eo e , ha
mix u e is used bo h in Po ugal and in hose colde egions.
F om he ex ensi e li e a u e e iew, i was also decided o s udy he e ec o one o he ypical polyme s
used o modi y asphal binde s, S y ene-bu adiene-s y ene (SBS), in wo di e en p opo ions, in o de o
analyse i s e ec on he wo kabili y, and esis ance o de o ma ion and c acking a low empe a u es.
Se e al labo a o y es s we e pe o med o analyse he unmodi ied bi umen and he wo polyme -modi ied
binde s, as well as he co esponding asphal mix u es. The low- empe a u e pe o mance was analysed
h ough he es s con ained in he Eu opean S anda d EN 12697-46 (CEN, 2012) o low- empe a u e
c acking p ope ies by uniaxial ension es s, bu many o he EN s anda ds we e used o e alua e o he
p ope ies o he binde and he mix u es. Howe e , he i s one will be o pa icula impo ance, gi en
he limi ed na ional expe ience in he low- empe a u e pe o mance o asphal mix u es un il now. The
easibili y o ca ying ou he selec ed labo a o y es s (labo a o y es ains) will also be assessed, as well
as he calcula ions and inal analysis o he cha ac e is ics o he binde and mix u es.
This disse a ion should con ibu e o depic as closely as possible he eal condi ions and beha iou o
which asphal pa emen s a e subjec ed o and expand he cu en knowledge abou he a iables in ol ed
in he comple e p ocess ha occu s when low empe a u es a e p esen . Subsequen ly, his wo k aims
o add some knowledge on he esponse o challenges anspo in as uc u es ace in egions wi h cold
clima es, bo h a he na ional le el (No heas o Po ugal) bu pa icula ly a he Eu opean le el, o
acili a e and encou age he expansion and pa icipa ion o Po uguese cons uc ion companies in an
inc easingly global ma ke .
1.3. Disse a ion s uc u e
This disse a ion is s uc u ed in o i e dis inc chap e s. This dis ibu ion was es ablished ollowing he
main phases o he s udy and he imeline in which hey we e execu ed. I s p ima y pu pose is o be e
cla i y and ansla e he di e en componen s o he esea ch in o a lawless and objec i e epo .
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
4
The i s chap e , he cu en one, se es as an in oduc o y segmen . I con eys he gene al con ex in
which he esea ch was b ough up as well as clea objec i es o he wo k and b oad pa ame e s.
Chap e wo en ails he li e a u e e iew. Di e en componen s o asphal mix u es a e discussed in his
chap e o con ex ualize his esea ch and he ad an ages and disad an ages o hei applica ion unde
he s udied condi ions. The empe a u e condi ions his esea ch in ol es a e also analysed.
The hi d chap e desc ibes he ma e ials u ilized in he p oduc ion o asphal binde s and mix u es, as
well as he ma e ial used as he bonding agen o he mechanical es s. In his chap e , he me hods and
echniques used o p oduce and cha ac e ize he asphal mix u es and hei componen s o e he a ious
phases o he s udy a e also de ailed and u he explained. Besides, he p ocesses o cha ac e iza ion
o he binde s a e also desc ibed. Las ly, special a en ion is gi en o he mechanical p ocedu es used o
s udy he low- empe a u e p ope ies o he asphal mix u es.
The ou h chap e p esen s he analysis o he esul s ob ained om he p e iously men ioned me hods
and es s, s a ing wi h he cons i uen s o he asphal mix u es and hei espec i e assessmen s: he
agg ega es and he asphal binde s. Then, an e alua ion o he asphal mix u es pe o mance is ca ied
ou , and inally, hei mechanical p ope ies a e analysed.
In he las chap e , chap e i e, he conclusions o he esea ch a e p esen ed, based on he esul s and
analysis ob ained om he p e ious chap e . In his chap e , i is also u he explained he pa icula
challenges ha a ose du ing he s udy and i s limi a ions. Fu u e wo ks a e sugges ed in o de o ad ance
he esea ch u he a e his disse a ion epo .
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
5
2. LITERATURE REVIEW
“I I ha e seen u he , i is by s anding on he shoulde s o gian s.”
Isaac New on
2.1. Asphal mix u es
Gene al p ope ies o asphal mix u es
Since immemo ial imes, he mo emen o people and goods has been di ec ly ela ed o human and
ci iliza ional de elopmen and he inc ease in he quali y o li e. These pa hs, ini ially pa hs aced by
pedes ian mo emen , ha e also e ol ed in numbe , in hei shape, layou , loca ion and quali y o he
ma e ials used o hei execu ion, as he means o anspo and echnology ha e e ol ed a ound hem.
The de elopmen o a na ion is ex ensi ely dependen on he connec i i y be ween i s a ious places o
impo ance, whe he hey a e u ban cen es, which concen a e popula ions and se ices, o places o
s a egic impo ance o hei unc ion o p oduc ion o de elopmen o esou ces. This connec i i y is
p o ided by anspo in as uc u es, which a e o ex eme impo ance in he de elopmen o any egion,
le alone, any na ion.
The bene i s om he in es men in he oad sec o a e indi ec , long- e m and no immedia ely isible.
Roads a e essen ial asse s o any na ion. In he pas , g a el oad su aces, cobbles one and g ani e se s
we e ex ensi ely used, bu hese su aces ha e mos ly been eplaced by asphal o conc e e pa emen s.
Pa emen design is one o he signi ican componen s in oad cons uc ion. When building highways and
oads, he pa emen consis s o a s uc u e composed o one o mo e cou ses, o assis he passage o
a ic wi h laye s o ini e hickness on a suppo su ace ob ained by ea hwo ks (Senço, 2001). The
p ima y unc ion o a pa emen is o esis and dis ibu e o he ounda ion he e ical loads p oduced by
he a ic; a second unc ion is o imp o e he olling condi ions in e ms o com o and sa e y, also by
esis ing he ho izon al e o s ha ac on i , c ea ing a mo e du able olling su ace, allowing he
ci cula ion o ehicles in a sa e, com o able and economical way.
The ca ying capaci y is a unc ion o he load dis ibu ion cha ac e is ics o he laye sys em. The laye s
wi h he highe quali y a e close o he applied load, a ou ing he wa e p oo ing o he pa emen and
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
6
p e en ing wa e om en e ing he lowe laye s o he ounda ion and hus, p e en ing s abili y issues
ela ed o he p esence o wa e .
The oad pa emen can be ca ego ized in o se e al ypes, acco ding o i s cons i u ion and mode o
beha iou : lexible, igid and semi- igid (B anco
e al.
, 2011).
Rigid pa emen s a e hose possessing a conside able lexu al s eng h o lexu al igidi y. Usually, he
su ace laye is cons i u ed by cemen conc e e. A igid paymen de i es i s capaci y o wi hs and loads
om lexu al s eng h. In hese ypes o pa emen s, hicknesses a e ob ained om he lexu al s eng h
o conc e e slabs and he comp essi e s eng h o he unde lying laye s. The igid pa emen has igidi y
and a high s i ness modulus in o de o dis ibu e he load o e a ela i ely wide a ea o soil. The
unde laye o he conc e e slab is con en ionally designa ed as base cou se, as shown in Figu e 1.
Figu e 1 – Rigid pa emen c oss-sec ion (The Cons uc o , 2020)
Cemen conc e e pa emen is he bes example o igid pa emen s. This ype o pa emen has some
ad an ages, which include: low main enance cos s, e y long li e, high alue as a po en ial base o u u e
esu acing wi h asphal , load dis ibu ion o e a wide a ea, dec easing base and subg ade equi emen s,
abili y o be placed di ec ly on poo soils, li le o no damage om oils and g eases and i m edges. Despi e
hese bene i s, i does also p esen some conside able challenges: high ini ial cos s, he equi emen o
ins alla ion o join s o con ac ion and expansion, gene ally a ough- iding quali y and high epai cos s.
Flexible pa emen s a e hose wi h low lexu al s eng h and a e lexible in hei s uc u al beha iou unde
he wheel loads. Because o i s low lexu al s eng h, his ype o pa emen de o ms i he subg ade
de o ms, so a well compac ed g anula s uc u e is an essen ial cha ac e is ic in o de o ob ain a lexible
pa emen o good quali y. Flexible pa emen s (Figu e 2) a e o med by h ee main laye s: asphal laye s,
g anula laye s (base and sub-base) and ein o cemen o ounda ion o pa emen bed. These laye s a e
buil o e he subg ade soils o ounda ion o he pa emen .

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
7
Figu e 2 – Flexible pa emen scheme (The Cons uc o , 2020)
The asphal laye s a e composed o bi uminous mix u es, also called asphal mix u es, consis ing
basically o agg ega es and asphal binde s. These mix u es a e u ilized in he su ace o wea ing cou se
laye ha si s in di ec con ac wi h he ehicle wheels, in he in e media e o binde laye and he base
laye . Flexible pa emen s a e designed based on he p inciple ha he in ensi y o a load diminishes as i
is ansmi ed downwa ds om he su ace by sp eading o e an inc easingly mo e subs an ial a ea. The
load is ca ied deep enough in o he g ound by he use o successi e laye s o g anula ma e ial. These
a ic loads a e ansmi ed o he successi e lowe laye s by g ain o g ain ans e . In sum, he wea
laye is designed o esis he ac ions o a ic di ec ly and ansmi hem smoo hly o he lowe laye s, in
addi ion o wa e p oo ing he pa emen and imp o ing olling condi ions, ha is, com o and sa e y
(Be nucci
e al.
, 2010).
Flexible pa emen s o e some g ea bene i s, which include: adap abili y o cons uc ion in s ages;
a ailabili y o lowe -cos pa emen s ha can be quickly buil ; abili y o be easily opened and pa ched; os
hea e and haw se lemen can be easie o epai han in igid o semi- igid pa emen s, and; hey possess
a highe esis ance o he o ma ion o ice glaze. Albei hese bene i s, hey also pose some issues in he
o m o highe main enance cos s, sho e li e span unde hea y use, po en ial damage by oils and ce ain
chemicals and weak edges ha may equi e cu bs o edge de ices. The bi uminous pa emen s and g a el
pa emen s a e some examples o lexible pa emen s.
Semi- igid pa emen s a e a ansi ional s a e be ween lexible and igid pa emen s. This ype o pa emen
possesses some ai s o bo h o he o he wo. F om he igid pa emen , i bo ows he lexu al s eng h,
al hough in a much lowe capaci y. Howe e , o compensa e o his lowe s eng h capaci y, i de i es
suppo by he la e al load dis ibu ion gi en by he lexible pa emen . Lean cemen conc e e, soil cemen
and lime-pozzolanic conc e e cons uc ion a e examples o semi- igid pa emen s.
A as po ion o oadways and highways a e cons uc ed wi h lexible pa emen s because o hei
ad an ages in low capi al cos , high iding quali y and ease o cons uc ion. Thus, a g ea deal o esea ch
has been done conce ning he asphal mix u es u ilized in hese pa emen s, since hey a e he main
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
8
componen in his con igu a ion. The eason o he as and p oli ic analysis, esea ch and de elopmen
o asphal mix u es lies in he ac ha wi h i s de elopmen and imp o emen , speci ic challenges
p esen ed by lexible pa emen s can be su moun ed o a leas , much imp o ed. The cu en s udy will
also ocus on asphal mix u es o lexible pa emen s.
As p e iously s a ed, asphal mix u es consis o agg ega es o di e en sizes and g adings, which a e
mixed wi h a ce ain amoun o binde , so ha he desi ed cha ac e is ics o each bi uminous laye o
he pa emen can be a ained. The agg ega es used o asphal mix u es can be c ushed ock, sand,
g a el o slag along wi h pa icula was e and by-p oduc s esul ing om he cons uc ion and demoli ion
ields. The la e ones can con ibu e o inc easing he sus ainabili y o he asphal mix u e. The ma ix
ma e ial is he binde , and his subs ance is usually a black iscous mix u e o hyd oca bons ob ained
na u ally o as a esidue om pe oleum dis illa ion, in which case is called bi umen. Nowadays, di e en
binde s no de i ed om pe oleum a e being de eloped, such as bio-based binde s, o minimise he
en i onmen al impac he cons uc ion o oads has (EAPA, 2019).
The e a e se e al ypes o asphal mix u es capable o esponding o he mos a ied demands equi ed
by a ic loads and wea he agen s. These mix u es can be classi ied in di e en ways. One o he
ca ego ies o classi ica ion conce ns he empe a u e o p oduc ion. They can be di ided in o ou classes,
wi h inc easing p oduc ion empe a u e: cold mix asphal (CMA), hal wa m mix asphal (HWMA), wa m
mix asphal (WMA) and ho mix asphal (HMA). CMA mix u es a e made a oom empe a u e using
bi umen emulsion o oam, and HWMA is p oduced wi h simila ma e ials a empe a u es sligh ly below
wa e apo iza ion. WMA is made in he 120 o 140 °C ange, abo e he wa e apo iza ion empe a u e
bu below HMA p oduc ion empe a u e. Finally, HMA is mixed up in he 150 o 180 °C empe a u e
ange depending on he used binde (Vai kus
e al.
, 2009). This classi ica ion is ep esen ed in Figu e 3.
This esea ch will use HMA mix u es since hey a e he mos commonly used ype o mix u es.
Asphal mix u es a e mos ly used ei he in he su ace cou se o in he binde cou se. This s udy will ocus
on mix u es o be used in he su ace cou se. The su ace o wea ing cou se consis s in he op laye o
he pa emen and mus be able o wi hs and high a ic and s esses de i ed om he en i onmen
a ound i wi hou he asphal mix u e exhibi unsa is ac o y c acking and u ing (EAPA, 2019). In o de
o he mix u e o p o ide com o o he use and assu e adequa e skid esis ance, i should possess
speci ic pa ame e s and cha ac e is ics such as, an e en p o ile, sui able ex u e ha allow o noise
educ ion, among o he s.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
9
Figu e 3 – Classi ica ion o asphal mix u es acco ding o p oduc ion empe a u e (Vai kus
e al.
, 2009)
Di e en ypes o asphal mix u es ha a ain o p o ide solu ions o hese equi emen s, among o he s,
ha e been c ea ed o e ime and a g ea deal o esea ch and in es iga ion has been pu in o hei
de elopmen . Some o hese mix u es a e asphal conc e e (AC),
bé on bi umineux mince
(BBM) o hin
laye asphal conc e e (AC-TL), e y- hin laye asphal conc e e (AC-VTL), ul a- hin laye asphal conc e e
(AC-UTL), s one mas ic asphal (SMA), ho olled asphal (HRA), po ous asphal (PA), mas ic asphal (MA),
among o he s (EAPA, 2019). Figu e 4 shows isual di e ences in agg ega e dis ibu ion and po osi y
be ween commonly used asphal mix u es.
Figu e 4 – Di e ence in he s uc u e o ypical asphal mix u es (EAPA, 2019)
S one Mas ic Asphal
This wo k will s udy a S one Mas ic Asphal (SMA) mix u e o he su ace laye . SMA ype o mix u es was
de eloped in Ge many in he 1960s. A he ime, s udded y es we e abundan in Ge many, which in
conjunc ion wi h he loads om he hea y ehicles ha equen ed he oads in abundance, became an
inc easing issue conce ning he low du abili y o he pa emen s (Blazejowski, 2011). SMA mix u es we e
c ea ed o o e come his issue, p o iding hea ily a icked oads wi h a du able, u - esis an wea ing
cou se by using a gap-g aded agg ega e s uc u e and a high con en o modi ied binde .
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
10
Due o he as expe ience, Ge many has had wi h SMA ype mix u es, se e al empi ically speci ica ions
based on composi ional ecipes ha e been pu o wa d since he echnical ZTV bi S b-84 was ini ially
published in 1984 (Mi anda
e al.
, 2019). Since hen, he use o his ype o asphal mix u e sp ead
h oughou he wo ld. In he Uni ed S a es, SMA mix u es ha e been in use since he ea ly 1990s. In bo h
con inen s, hese mix u es ha e pe o med well o many yea s, and hey con inue o be used when
speci ic cha ac e is ics a e equi ed o he pa emen (B own
e al.
, 1997).
Cu en ly, he Eu opean S anda d EN 13108-5 (Bi uminous mix u es - Ma e ial speci ica ions - Pa 5:
S one Mas ic Asphal ) p o ides some equi emen s o SMA p ope ies, including olume ic
cha ac e is ics, esis ance o pe manen de o ma ion and o he s.
SMA is an asphal mix u e which is mainly cha ac e ized by a discon inuous g ada ion o he mine al
pa icles, which esul s in a coa se agg ega e skele on. This s one on s one e ec p o ided by he skele on
does no occu in he mo e con en ional dense mix u es cha ac e ized by con inuous pa icle g ada ion.
The bi uminous mas ic has he equi emen o illing he ai oids olume p esen ed be ween he coa se
agg ega e o be able o ensu e excellen cohesion o his skele on. This mas ic is usually cons i u ed by
ine agg ega es, ille , asphal binde and some imes s abilise s (Mi anda
e al.
, 2019).
Acco ding o EAPA (2018), he binde s u ilized in hese ypes o mix u es a e usually polyme -modi ied
bi umens and s anda d bi umens wi h ib es, he la e selec ed on lowe a ic olume oads.
This mix u e design has usually been based on empi ical speci ica ions in o de o achie e he s one on
s one e ec be ween he coa se agg ega e and hus, ensu ing adequa e pe o mance o pe manen
de o ma ion. This p ocess has been i e a i e, by con inuously a ying he pa icle g ading, un il ob aining
a minimum binde con en ha can s ill ensu e adequa e po osi y and minimum oids in he mine al
agg ega e, along wi h addi ional pe o mance- ela ed equi emen s (Mi anda
e al.
, 2019). The
pe o mance o hese mix u es is mos ly ela ed o i s skele on e ec , which can a ec i s essen ial
p ope ies, such as u ing esis ance and wo kabili y.
SMA possesses se e al bene i s because i can educe ligh e lec ion, imp o e su ace d ainage and
educe he le el o a ic noise. Wi h i s discon inuous skele on, i can o e an imp o ed dispe sion o he
a ic loads and hus, p e en u ing and inc ease esis ance o wea ing. Likewise, i also p o ides good
mac o ex u e and high su ace oughness, which con ibu e o imp o ing skid esis ance (Blazejowski,
2011). Wi h he expe ience o e he yea s, i has also been ound ha s ipping, su ace c acking (ei he
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
17
ma e ial may cause some di icul ies du ing he manu ac u ing p ocess as well as du ing pa ing and
should be conside ed when selec ing he agg ega e g ading (To h
e al.
, 2016).
Some o he ad an ages o using his ma e ial, along wi h he p e iously explained ecycling dimension,
come om i s ela i ely lowe cos s in compa ison wi h PMB, and he po en ial o imp o ing a igue
esis ance, educe e lec i e c acking and inc easing u ing esis ance (Becke , 2001).
2.3. Bi umen
Bi umen can be de ined, om a comme cial poin o iew, as a he moplas ic ma e ial ha was usually
o ela i ely low cos and has been widely used o se e al applica ions such as oo ing, pa ing, indus ial
p oduc s, among o he s. In he la e applica ions, pa emen mix u es and indus ial applica ions, i is
c ucial ha he bi umen possesses esis ance o bo h clima ic challenges and demanding a ic loads;
o which he heological p ope ies o his ma e ial a e o g ea impo ance (Lesueu , 2009).
Wi h he g owing conce n abou he du abili y and quali y o he pa emen s, i has been an inc easing
conce n o e ime o p o ide mo e in-dep h s udies o he essen ial elemen s ha cons i u e a pa emen .
One o hese elemen s is he bi umen, which pe mi s he in ol emen o all he elemen s h ough i s
bonding capabili ies. Acco ding o he Eu opean S anda d EN 12597 (Bi umen and bi uminous binde s
– Te minology), bi umen is de ined as a “
i ually in ola ile, adhesi e, and wa e p oo ing ma e ial de i ed
om c ude oil, o p esen in na u al asphal , which is comple ely o nea ly comple ely soluble in oluene,
and e y iscous o nea ly solid a ambien empe a u es
”.
Analysis o he molecula weigh dis ibu ion shows ha bi umen is a complex mix u e o a ound 300 up
o 2000 chemical compounds, wi h an a e age alue o 500 o 700. This quan i y o chemicals makes
bi umen a challenge o ho oughly cha ac e ize. Bi umen is usually di ided in o wo p incipal cons i uen s:
asphal enes, a cons i uen o he discon inuous phase, and mal enes, a cons i uen o he con inuous
phase, wi h he la e being u he classi ied in o sa u a es, a oma ics and esins. These a e known as
an analysis me hod named SARA, Sa u a e, A oma ic, Resin and Asphal ene (Po o
e al.
, 2019).
Ha ing a ho ough unde s anding o he di e en aspec s o he cha ac e is ics o bi umen is o pa amoun
impo ance. This knowledge p o es i s impo ance when pa icula challenges a ise, mainly in some
bi umen applica ions, which include une en dispe sion, discon inui y in phase, ins abili y wi h polyme s
o addi i es, among many o he s. These di icul ies can appea in he p oduc ion s age as well as in he

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
18
applica ion (Po o
e al.
, 2019). I is commonly accep ed ha he o iginal cha ac e is ics o bi umen a e
highly dependen on i s p oduc ion and p ocessing echniques and i s c ude oil cha ac e is ics (Paliukai
e al.
, 2014). C ude oils o a highe quali y and p ope dis illa ion p ocesses can enhance he bi umen
a ibu es, gene ally hea ie c ude oils de i e in highe bi umen yields (Read and Wi heoak, 2003).
Due o hei unc ion in asphal mix u es, binde s mus ha e an adequa e chemical composi ion as well
as a su icien iscosi y o be able o pe o m hei unc ion as he ma ix in he mix u e. They should be
nei he oo liquid no oo iscous o in ol e he agg ega es adequa ely. The binde is a undamen al
componen o he asphal mix u e, as i is esponsible o ac ing as he glue be ween he agg ega es and
ensu ing hei cohesion (Bu gue e, 2013).
F om a p ac ical poin o iew, bi umen mus be luid enough a e y high empe a u es, such as 160 °C,
o possess enough wo kabili y in o de o he agg ega es o be app op ia ely and homogeneously coa ed
du ing mixing. I mus also be s i enough a high empe a u es o be able o esis u ing (Po o
e al.
,
2019). Finally, i mus emain so and elas ic enough a low empe a u es o esis he mal c acking
(Lesueu , 2009). All o hese equi emen s can appea almos opposi e and ha d, i no impossible, o be
ound in one single ma e ial. Mo eo e , in some applica ions, he pe o mance o con en ional bi umens
may no be sa is ac o y enough. In some enginee ing p ojec s, con en ional bi umen can be oo b i le in
cold en i onmen s and oo so in wa m ones. This limi ed pe o mance in empe a u e anges is one o
he main disad an ages o nea bi umen, which can limi i s use in some oo ing and pa emen
applica ions (Po o
e al.
, 2019).
Since he a ic speed and olume ha e been consis en ly inc easing in ecen decades, pa emen s ha e
been subjec ed o a conside able load inc ease which was no planned when pa emen s we e i s
designed and execu ed. This si ua ion has no ably diminished he li e span o he asphal pa emen s,
inc easing i s main enance cos s and posing a highe isk o he sa e y and com o o i s use s. The e o e,
a a ie y o addi i es and modi ie s ha e been used o enhance bi umen pe o mance, and espond
adequa ely o he new pa emen challenges. These include polyme s, chemical modi ie s, ex ende s,
oxidan s and an ioxidan s, hyd oca bons and an i-s ipping addi i es (Po o
e al.
, 2019).
Polyme s a e a as ield o modi ie s ha ha e been esea ched in g ea de ail. By imp o ing bi umen
cha ac e is ics such as esis ance o de o ma ions, he mal c acking, su ace b eakdown and
suscep ibili y o empe a u e, PMBs ha e o eplace nea bi umens in many applica ions, bo h in ini ial
pa ing as well as in main enance ea men s. Some o hese include ho and cold mixes, c ack sealing
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
19
and ecycled solu ions. PMBs a e used when imp o ed pe o mance is needed and, in some cases, also
when he e is a necessi y o educe he pa emen li e cycle cos s (Becke , 2001).
Pa icula ly in SMA ype mix u es, addi i es a e usually used due o he highe quan i y o bi umen p esen .
These a e in ended o p e en he leaking o he binde by inc easing i s consis ency and imp o ing i s
beha iou o empe a u e a ia ions (Becke , 2001). These addi i es a e usually polyme s o ib es, o
e en he combina ion o bo h. In he cu en esea ch wo k, only polyme s we e u ilized.
Acco ding o To es (2014), he choice o base bi umen should ake in o accoun ac o s such as p ice,
ma ke a ailabili y, cha ac e is ics and e en p e ious success ul expe iences o binde s used in asphal
mix u es, since he binde is he componen ha mos in luences he pe o mance o he mix u es.
Polyme modi ied binde s
Bi umens ha a e exposed o se e e o ough condi ions, such as s eep g adien s, high a ic loading,
ex eme oad su ace empe a u es and o he s, equi e be e pe o mance han o dina y bi umens. In
o de o imp o e he p ope ies o bi umen, polyme s a e added o he bi umen o o m modi ied binde s.
Acco ding o he Eu opean S anda d EN 12597 (Bi umen and bi uminous binde s – Te minology),
modi ied bi umen is a “
bi uminous binde whose heological p ope ies ha e been modi ied du ing
manu ac u e by he use o one o mo e chemical agen s
”. Modi ied binde s pe o m be e conce ning:
adhesion, du abili y, elas ici y, de o ma ion esis ance, lexibili y a low empe a u es, high iscosi y a
high empe a u es, among o he cha ac e is ics (Van Ams e dam, 2000).
The polyme modi ied binde s (PMB) a e p oduced by mechanically mixing o by he chemical eac ions
o bi umen and one o mo e polyme s, among hose p esen ed in Table 1, whose pe cen age can usually
ange om 3% o 10% o e en highe (Po o
e al.
, 2019).
The PMBs can be a anged in o wo sepa a e ca ego ies acco ding o hei s uc u e, homogenous binde s
and non-homogenous binde s. These wo b oad g oups a e classi ied ega ding he exis ence, o lack
he eo , o wo dis inc phases, obse ed in he binde s, which can be de ec ed on a mic oscopic le el.
Homogenous binde s a e, as he name implies, binde s ha possess a uni o m s uc u e o composi ion,
mo e speci ically hey a e de ined as a blend o bi umen and polyme whe e wo dis inc phases canno
be de ec ed on a mic oscopic le el. These phases a e in e wo en o such an ex en ha he modi ied
binde beha es as a single-phase ma e ial (SABITA, 2015).
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
20
Table 1 – Ca ego ies o polyme s mainly used in bi umen modi ica ion (Po o
e al.
, 2019)
Ca ego ies Polyme
The moplas ic Polyme s
Polye hene (PE)
Polyp opylene (PP)
E hylene-Vinyl-Ace a e (EVA)
PVC
EBA
The moplas ic Elas ome s Copolyme s s y ene-bu adiene-s y ene (SBS)
Copolyme s s y ene-isop ene-s y ene (SIS)
The mose s
Epoxy esin
Polyu e hane esin
Ac ylic esin
Phenolic esin
Na u al and syn he ic ubbe s
S y ene-bu adiene- ubbe (SBR)
Na u al ubbe
Polyole ines
Reclaimed y e ubbe
Bi umen chemical modi ie s
Sulphu (S)
Polyphospho ic acid (PPA)
Reac i e polyme s
Maleic Anhyd ide (MAH)
Nanocomposi e modi ie s
Some o he polyme s mos equen ly u ilized o p oduce homogenous binde s a e s y ene-bu adiene-
s y ene (SBS), s y ene-bu adiene- ubbe (SBR), s y ene isop ene ubbe (SIR), e hylene- inyl-ace a e
(EVA), eac i e elas ome ic e polyme (RET) and na u al ubbe la ex, among many o he s.
Non-homogenous binde s a e cha ac e ized by ha ing wo dis inc phases, which can be de ec ed on a
mic oscopic le el. These phases obse e di e ences in p ope ies acco ding o wha s age a es is
pe o med, hey display beha iou wi h a non-uni o m s uc u e o a angemen , as i is implied by hei
nomencla u e. The p ima y ma e ial ha alls unde his ca ego y and is inco po a ed in o binde s consis s
o c umbed ubbe s ecycled om y es (SABITA, 2015), which a e pa ially dissol ed in a bi umen ma ix.
Ano he classi ica ion can be made acco ding o wo b oad ca ego ies: plas ome s and elas ome s. Wi hin
hese wo g oups, u he sub-g oups exis , o which, he moplas ic polyme s in he plas ome g oup and
he moplas ic ubbe s in he elas ome g oup a e he mos common (Ai ey, 2001).
S uc u es wi h elas ome ic ea u es, hose ha p esen esis ance o pe manen de o ma ion and
eco e y o he o iginal shape a e loading, a e hose ob ained by using elas ome ic modi ie s in bi umen
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
21
(Ai ey, 2002). As an example o an elas ome is c umbed ubbe , usually made om g ound y es. Se e al
echnologies a e in place o using g ound i e ubbe . This ma e ial is used p ima ily o add ess u ing.
Plas ome s a e used o imp o e he high- empe a u e p ope ies, i.e., he u ing esis ance o modi ied
binde s and mix u es. When hese a e inco po a ed in o he bi umen, he esul ing s uc u e is a igid
h ee-dimensional ne wo k ha esis s de o ma ion (Ai ey, 2002). Low-densi y polye hene (LDPE) and
e hylene- inyl ace a e (EVA) a e examples o plas ome s used in asphal modi ica ion.
The mos commonly used chemical modi ie is polyphospho ic acid (PPA). This modi ie may be used in
combina ion wi h polyme s o inc ease he high- empe a u e s i ness.
O he modi ie s ha may be used include asphal binde ex ende s (p ima ily sulphu ) and hyd oca bon
ma e ials. Hyd oca bons can p oduce ei he ha dening o so ening e ec s. Ha dening ma e ials can be
added o inc ease u ing esis ance. So ening agen s o eju ena o s a e used o lowe he iscosi y o
aged asphal binde s in mix u es con aining ecycled asphal pa emen o RAP (Walke , 2019).
Ex ensi e esea ch in asphal mix u es and pa emen echnology has p oduced g ea solu ions o he
p oblem o inc easingly highe a ic olumes and loads. One o hese solu ions is polyme modi ied
bi umens (PMB), wi h he ad an ages and disad an ages p esen ed in Figu e 5. These a e inc easingly
u ilized ac oss he wo ld, and hey p o ide supe io pe o mance (To h
e al.
, 2016).
Me hods o inco po a ion o polyme s in asphal mix u es
The e a e h ee dis inc me hodologies o inco po a ing polyme s in o he asphal mix u es: as an
agg ega e eplacemen , as an agg ega e coa ing o as bi umen modi ie . The echniques u ilized o his
inco po a ion consis o he d y p ocess and he we p ocess.
As Hassan
e al.
(2014) desc ibe, “
he d y p ocess in ol es he blending o c umb ubbe wi h ho
agg ega es be o e mixing wi h bi umen
”. This p ocess essen ially eplaces a po ion o he agg ega es
wi h he modi ying agen in a solid o m, g anules o sha ings, be o e mixing wi h he bi umen, which
makes his agen o e ec i ely wo ks as an elas ic agg ega e wi hin he mix u e (B andão, 2015). The
mix u es p oduced by he d y me hod a e conside ed o be simple because no chemical eac ions occu
be ween he wo componen s. In his case, he polyme is conside ed as a ille which gi es speci ic
p ope ies o he mix u e (Bou e in
e al.
, 1989).
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
22
Figu e 5 – Ad an ages and disad an ages o modi ied binde s compa ed wi h con en ional binde s
(SABITA, 2015)
The same au ho s ha e ho oughly analysed his p ocess and i s sub le ies, as well as i s ad an ages and
disad an ages. The ad an ages esul om subs i u ing pa o he agg ega es in he mix u e while
imp o ing he elas ic p ope ies and assu ing some bi umen modi ica ion o he mix u e. Con e sely,
some disad an ages mus also be poin ed ou , mainly and al hough his me hod allows o he use o
mo e signi ican pe cen ages o polyme and p esen s lowe cos s in he ini ial s ages, in gene al, i

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
23
appea s ha i s pe o mance is no as good as he esul s obse ed om he we p ocess (B andão,
2015). Ano he conce n poin ed ou among he schola s is he lack o s anda ds and inconsis en
pe o mance, which in u n esul s in scep icism among p ac i ione s and esea che s in selec ing his
p ocess o e he we me hod, despi e ha ing he po en ial o ecycle mo e c umb ubbe , since i uses a
highe p opo ion o polyme in compa ison. All o hese easons ansla e in o he o e whelming majo i y
o asphal pa ing p ojec s in ol ing c umb ubbe op ing o use he we p ocess ins ead o he d y me hod
(Hassan
e al.
, 2014).
In he we me hod, he solid polyme is mixed wi h he bi umen a high empe a u es gi ing ise o a
modi ied binde so ha i is used in he modi ied asphal mix u e o be applied in he pa emen a a la e
s age. In he bi umen modi ica ion p ocess, he polyme is in oduced in he bi umen, which is s ill ho
and luid, du ing a speci ied pe iod, o gua an ee he in e ac ion be ween he polyme and he bi umen
(To es, 2014).
In his me hod, he mix u es be ween he wo componen s a e said o be complex, because chemical
eac ions o some o he in e ac ion occu s be ween he wo pa s o he mix u e (Bou e in
e al.
, 1989).
The e o e, one o he signi ican ad an ages o he we me hod pe ains o he mo e e ec i e modi ica ion
o he binde , which is also one o he easons his p ocedu e is hea ily u ilized by he indus y (Hassan
e al.
, 2015).
The modi ied binde , p e e ably p oduced a a bi umen p ocessing plan , is hen deli e ed and added o
he agg ega e du ing asphal mix p oduc ion. In his p ocess, he polyme eac s wi h he base bi umen,
swelling and pa ial dissol ing he polyme and hus, abso bing he oils om he bi umen in o he ubbe
ma ix (Gawel
e al.
, 2006).
Gene ally, i has been sugges ed ha he e is a highe deg ee o ubbe -bi umen in e ac ion wi h enhanced
p ope ies in he we p ocess han he d y p ocess, he eby making he we p ocess he p e e ed me hod
o modi ica ion. One o he main aspec s o polyme modi ica ion is he in e ac ion be ween he polyme
and bi umen, which is conside ed i al o unde s anding be e he concep o polyme modi ica ion in
bo h we and d y p ocess me hods. In e ac ion e e s o he di usion o he ligh e bi umen ac ions,
a oma ic oils in he mal enes, in o he polyme , which leads o he swelling o he polyme pa icles. The
swelling o he polyme as a esul o he polyme -bi umen in e ac ion is shown schema ically in Figu e 6
(Hassan
e al.
, 2014).
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
24
Figu e 6 – Schema ic o ubbe swelling in ubbe -bi umen in e ac ion (Hassan
e al.
, 2014)
When he polyme ge s in con ac wi h bi umen, i gene ally abso bs he mal enes ac ion, which has a
low molecula weigh and lea es he esidual bi umen con aining a highe po ion o asphal enes, wi h
high molecula weigh hus inc easing he PMB iscosi y. The mal enes ac ion di uses in o he polyme
pa icles, inc easing he dimensions o he polyme ne wo k un il equilib ium swelling is achie ed. Fac o s
such as he empe a u e and ime o he con ac be ween bi umen and polyme , he chemical composi ion
o bi umen, polyme ype and size we e all ound o a ec he a e o swelling (Hassan
e al.
, 2014).
2.4. Low- empe a u e condi ions
The empe a u e o he su ace o pa emen s can a y signi ican ly wi h he a ia ion o clima ic ac o s
such as adia ion, wind speed, a mosphe ic p essu e, and low ambien empe a u e, among o he s. This
su ace empe a u e is mos ly ela ed o he su ace cha ac e is ics o he pa emen ma e ial as opposed
o he hea ans e p ope y o he pa emen . Acco ding o Wang
e al.
(2014), he coe icien s o he mal
conduc i i y o asphal mix u es can a y conside ably because o he di e ence in agg ega es. In hei
s udy on he ac o s in luencing he empe a u e o he su ace o he pa emen , hey obse ed ha when
all ex e nal elemen s we e he same, he esul ing calcula ed empe a u es o a pa emen su ace we e
also he same, despi e he di e ence in coe icien s o he mal conduc i i y. This obse a ion explains he
impo ance he ex e nal ac o s ha e on de e mining he empe a u e o he pa emen su ace and
he e o e, he necessi y o simula e hem du ing es ing condi ions accu a ely.
Mo e subs an ial a ia ion in empe a u es will be eco ded a loca ions close o he pa emen su ace,
which in u n will lead o highe he mal s esses. E en hough he magni ude o he empe a u e a ia ion
in win e is smalle han in summe , he pa emen is subjec ed o eezing and hawing cycles. The mos
c i ical condi ion in he su ace laye , in win e condi ions, is he diu nal empe a u e, al hough bo h
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
25
seasonal and diu nal a ia ions o empe a u e should be conside ed when designing a su ace laye
(Wang
e al.
, 2014).
Low empe a u e c acking is one o he mos common ailu e modes o lexible pa emen s in cold clima e
zones (Ala aş and Yilmaz, 2017, S imilli
e al.
, 2017). These egions a e cha ac e ised by daily
empe a u e d op ha can be ema kably apid, e y long cold seasons and he lowes empe a u es
expe ienced can be e y low. All hese ac o s will play a ole in he con inuous main enance needed o
keep he oads in accep able se ice condi ions, which can esul in high di ec and indi ec cos s.
Pa emen s execu ed in colde egions a e subjec ed o signi ican a ia ions in empe a u e. No only
when i comes o he le el o empe a u e hey mus endu e bu also, o he pace o cooling. The a ia ion
o his cooling a e can c ea e ensile s esses de i ed om he cha ac e is ic o asphal mix u es o ex end
when hea ed and con ac when cooled. These s esses occu because he asphal laye is cons ained
in he pa emen s uc u e and is unable o elie e he he mal s esses by in e nal elaxa ion. As a esul
o he d op in empe a u e, he mal ensile s esses inc ease, and when hey exceed he ac u e s eng h
o he mix u e, c acks due o low empe a u e may appea (Pszczola and Szydlowski, 2018). Mic oc acks
ini ially appea on he su ace o he pa emen when he s ess o he pa emen exceeds i s ensile
s eng h. I he low- empe a u e cycles con inue, which is he usual scena io in colde egions, hese
mic oc acks p opaga e h ough he pa emen leading o a mo e se e e c acking p oblem in he mix u e
(Das
e al.
, 2012).
In colde zones, when wa e ills hese c acks du ing he win e mon hs, i eezes, and ice lenses along
wi h os hea e can de elop. This condi ion esul s in he loss o ines and o ma ion o oids h oughou
he pa emen , leading o a load-bea ing capaci y educ ion. Thus, i is o c ucial impo ance o ake in o
accoun all he a iables ha may a ec he pa emen in colde egions, du ing he designing s age. I
hese a e no adequa ely conside ed, i can lead o he men ioned o ma ion o c acks ha in u n esul
in he educed se ice li e o he pa emen , high main enance cos s and poo iding quali y (Isacsson and
Zeng, 1997). This condi ion, along wi h he change in he mic o-s uc u al s ess mechanism, de e mines
he ac u e esis ance beha iou o asphal mix u es o empe a u e (Kim and Hussein, 1997). Howe e ,
much o he pa emen dis esses, such as u ing, mois u e-induced damage, among o he s, may appea
on asphal pa emen s ha ha e been in use o an ex ended pe iod (Ala aş and Yilmaz, 2017).
The low- empe a u e p ope ies o asphal mix u es can be, somewha , indi ec ly de i ed om bi umen
p ope ies. The pene a ion dep h is empi ical, albei only oughly, co ela ed wi h asphal binde
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
26
pe o mance (Pa emen In e ac i e, 2019). Despi e his, binde es ing alone may no be su icien o
p edic he e ec o imp o emen s, such as addi i es and modi ied bi umen, ega ding he esis ance o
he mix u e o he mal s esses (Pszczola and Szydlowski, 2018).
In o de o accu a ely assess he ac o s ha a ec he asphal mix u es in colde egions, se e al
labo a o y es s ha e been de eloped. One o hese me hods is he he mal s ess es ained specimen
es (TSRST), which de e mines he c i ical c acking empe a u e ha esul s om a single d op in
empe a u e o an ex emely low alue obse ed du ing se e e win e s. The es p esen s many
ad an ages, al hough wi h some limi a ions. Because he ailu e empe a u es ob ained om he es
depend on he es ablished cooling a e, he esul s o he mal s ess and empe a u e a ac u e should
be ega ded as a compa a i e measu e be ween asphal mix u es (Pszczola and Szydlowski, 2018).
O he cha ac e is ics can be es ed by di e en me hods, such as ensile s eng h. One o he me hods
ha desc ibe he di ec ensile s eng h o asphal mix u es a low empe a u es is he uniaxial ension
s ess es (UTST). Ano he is he indi ec ensile es (IDT), which also measu es c eep compliance. The
bending beam heome e (BBR), can also be used o ob ain he asphal binde s eng h a low
empe a u es. Ano he me hod o desc ibe he s eng h p ope ies o asphal mix u es a low empe a u es
is o use lexu al s eng h (bending beam es ) a low empe a u es.
F ac u e p ope ies o asphal pa emen s can be de ined based on ac u e mechanics heo y and can
be s ic ly ela ed o labo a o y es esul s. The e a e se e al es me hods o assess ac u e pa ame e s,
including he bending o single edge and no ched beams (SENB), bending o semi-ci cula beams (SCB),
and ension o disc-shaped specimens (DC-T). One o he mos sui able and equen ly used me hods is
he bending es o semi-ci cula specimens (SCB). Fo be e c acking cha ac e iza ion, mo e pa ame e s
can be assessed, like ac u e ene gy (p e-peak and pos -peak), oughness index, and lexibili y index,
among o he s (Pszczola and Szydlowski, 2018).
Ano he indica o o he po en ial o c ack o ma ion is he elaxa ion po en ial o a mix u e gi en by he
elaxa ion modulus. I ep esen s he capaci y o a mix u e o dissipa e he he mal-induced s ess. This
capaci y plays a i al ole since he highe he elaxa ion po en ial, he lowe he po en ial o each he
ailu e poin and hus, o o m c acks. Mix u es cha ac e ized by as e decay o elaxa ion modulus a e
less p one o c acking a low empe a u e and can be mo e sui able o use in cold clima e egions (S imilli
e al.
, 2017).
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
33
This me hod is pe o med wi h a ing and ball appa a us, shown in Figu e 12(a). The ini ial es
empe a u e is es ablished a 5 °C and hen g adually augmen ed a a a e o 5 °C pe minu e, un il he
so ened bi umen ouches he me al pla e placed a a dis ance o 25.0 mm ± 0.4 mm, as exempli ied in
Figu e 12(b). The empe a u e a he end o he es is hen eco ded, which e eals he so ening poin .
Figu e 12 – (a) Ring and ball appa a us; (b) So ening poin a e es ing
Needle pene a ion
The needle pene a ion de e mina ion me hod is a es s anda dized by he Eu opean S anda d EN 1426
(Bi umen and bi uminous binde s - De e mina ion o needle pene a ion). This p ocedu e indi ec ly
de e mines he consis ency, mo e speci ically he ela i e ha dness, o bi umen and asphal binde s. The
highe he pene a ion, he so e he bi umen. Con e sely, he lowe he pene a ion, he ha de he
bi umen. Bi umens, in Eu ope, a e classi ied acco ding o he alues ob ained om his es .
In he pene a ion es , a s anda d needle pene a es e ically in o a sample o he bi umen unde speci ic
condi ions o empe a u e, load and du a ion o loading. Acco ding o he s anda d EN 1426, o
pene a ions up o app oxima ely 330 × 0.1 mm ( he mos common ones o ypical bi umen), he
ope a ing pa ame e s mus be a a es empe a u e o 25 °C. Howe e , o expec ed pene a ions abo e
app oxima ely 330 × 0.1 mm, he es empe a u e mus be educed o 15 °C, main aining he
pa ame e s o alue and load du a ion, in addi ion o he condi ions shown in Table 4.
The needle, weighing 100 g, is eleased o 5 seconds. A e his ime, he dep h o pene a ion in o he
bi umen is measu ed in en hs o a millime e. Figu e 13 illus a es his p ocess.
a)
b)

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
34
Table 4 – C i e ia o conduc ing he needle pene a ion es
Pene a ion
(0.1 mm)
In e nal
dep h
(mm)
In e nal
diame e
(mm)
App oxima e
olume o sample
(ml)
App oxima e ime o ai
cooling o wa e
condi ioning (min)
pen < 160 35 55 80 60
160 ≤ pen < 330 45 70 170 75
330 ≤ pen < 500 60 70 230 90
Figu e 13 – Bi umen pene a ion es
Th ee es s mus be ca ied ou in di e en loca ions o he sample and should no di e signi ican ly om
each o he o he es o be conside ed alid. The inal pene a ion alue o he bi umen is gi en by he
a e age o he h ee measu emen s. Fo example, a pene a ion o 50 o 70 × 0.1 mm indica es a 50/70
pene a ion g ade bi umen. The pene ome e used in his es is he semiau oma ic pene ome e om
Con ols G oup, model 81-B0101/D, shown in Figu e 14.
Figu e 14 – Semiau oma ic pene ome e , Con ol G oups, model 81-B0101/D
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
35
Resilience
The esilience es was ca ied ou in acco dance o he Eu opean S anda d EN 13880-3 (Ho applied
join sealan s - Pa 3: Tes me hod o he de e mina ion o pene a ion and eco e y – esilience), and i
aims o de e mine he elas ic eco e y capaci y o he modi ied bi umen indi ec ly. Resilience is he abili y
o an elas ic ma e ial o abso b ene gy and elease ha ene gy as i sp ings back o i s o iginal shape
(Asphal Ins i u e, 2020), i.e., is he capaci y o a s ained body ( he PMB) o eco e i s size and shape
a e de o ma ion caused by comp essi e s ess.
This echnique consis s o a me hod o de e mining he pene a ion and eco e y ( esilience) o a
modi ied bi umen using a s anda d pene ome e i ed wi h a ball pene a ion ool. In his p ocedu e, a
bi umen sample is placed in a wa e ba h o 60 o 90 minu es a 25 °C. Then, a comp ession load is
applied o he bi umen sample, h ough a 17 mm diame e me al sphe e, un il a 10 mm de o ma ion is
achie ed. Once his alue is eached, he load is main ained o an addi ional 5 seconds wi hou inc easing
de o ma ion. The load is hen emo ed om he sample o 20 seconds, and he de o ma ion eco e y in
he es ed bi umen sample is measu ed. The esilience o eco e y o he pene a ion o he bi umen
sample is calcula ed acco ding o Equa ion 1, whe e P is he ini ial pene a ion alue o he sphe e
(0.1 mm) and F is he pene a ion alue a e eco e y (0.1 mm).
𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅𝑅 (𝑅𝑅) (%)=𝑃𝑃+100 −𝐹𝐹
(1)
The esilience es was only pe o med on he polyme -modi ied binde s because he base bi umen does
no p esen esilien cha ac e is ics since i is no modi ied by any polyme , i.e., i is no able o eco e
imposed de o ma ion.
Dynamic iscosi y
The dynamic iscosi y es is a me hod based on he Eu opean S anda d EN 13302 (Bi umen and
bi uminous binde s - De e mina ion o dynamic iscosi y o bi uminous binde using a o a ing spindle
appa a us) bu wi h an adap a ion o he p ocedu e p oposed by Sil a
e al.
(2009) in which he ini ial
alue o he es empe a u e is 100 °C and is inc eased by 10 °C o each new measu emen . This
p ocedu e was pe o med wi h a B ook ield o a ional iscome e , model DV-II+P o (Figu e 15). The
p ocedu e consis s o o a ing a spindle a a cons an speed, inside a luid bi umen sample (which o ces
he es o be ca ied ou a high empe a u es), measu ing he o que applied by he iscome e .
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
36
Figu e 15 – B ook ield o a ional iscome e , model DV-II+P o
The spindle (Figu e 16 (a)) is a cylind ical objec , and he bi umen sample will be pou ed in a cylind ical
con aine (Figu e 16 (b)) wi h a diame e sligh ly la ge han he spindle.
Figu e 16 – (a) spindle and; (b) bi umen con aine s used in he iscome e
The o a ion e o de e mines he o que necessa y o o e come he esis ance p o ided by he iscosi y
o he luid ma e ial. The o a ional mo emen is exe ed be ween he bi umen and he spindle su ace so
ha he o a ion speed is cons an and is measu ed using he equipmen men ioned. This e o is
p opo ional o he iscosi y. Acco ding o Van Ams e dam (2000), he iscosi y measu es he low a e
o a liquid and i s consis ency ( hickness and smoo hness). A liquid has a low iscosi y i a o ce is applied
o i and, in esponse, i mo es quickly. Con e sely, i i mo es slowly, i has a high iscosi y.
In his wo k, he iscosi y measu emen s a ed a 100 °C and was g adually inc eased by 10 °C un il
he nex empe a u e is s abilized, which usually happens a e abou 10 minu es, and he measu ed
a)
b
)
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
37
alues a e hen eco ded, wi h each s ep moni o ed by a compu e . This echnique is epea ed un il he
empe a u e o 180 °C is eached. Abo e 100 °C, he bi umen ac s almos en i ely as a iscous luid,
and so his p ocedu e cha ac e izes he bi umen s i ness by de e mining i s heological p ope ies.
Rheological p ope ies
The heological p ope ies o he asphal binde s a high and in e media e empe a u es we e de e mined
using he dynamic shea heology es . This es was based on he Eu opean S anda d EN 14770
(Bi umen and bi uminous binde s - De e mina ion o complex shea modulus and phase angle using a
Dynamic Shea Rheome e ), and he equipmen used o his p ocedu e was a Dynamic Shea Rheome e
(DSR) by Bohlin Ins umen s, shown in Figu e 17.
Figu e 17 – Dynamic Shea Rheome e (DSR) by Bohlin Ins umen s
The p ocedu e in ol es de e mining he complex shea modulus and phase angle o he asphal binde s
o e a ange o es equencies and empe a u es when es ed in oscilla o y shea . This p ocedu e
in ol es de e mining he iscoelas ici y o he bi umen, which is cha ac e ized by he phase angle, δ, he
complex modulus, G*, he elas ic modulus, G’ and he iscous modulus, G’’. The DSR heome e applies
o sional s ains o bi umen samples a a equency o 10 ad/s, while measu ing he o que applied o
achie e hese s ains. By knowing he o que e o and he espec i e o sion de o ma ion, i is possible
o de e mine he heological p ope ies o he bi umen.
The bi umens we e es ed a di e en empe a u es, anging om 19 °C o 88° C. The heological
p ope ies o he binde s a e de e mined wi h di e en pla es acco ding o he es ed empe a u es. Fo
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
38
he lowe empe a u es, be ween 19 °C and 40 °C, a smalle pla e o 8 mm in diame e is used wi h a
bi umen sample wi h 2 mm o hickness. Fo he highes empe a u es, om 46 °C o 88 °C, a la ge
pla e wi h 25 mm in diame e is used wi h a bi umen sample wi h a hickness o 1 mm (Figu e 18). This
change o he pla es ensu es a linea heological beha iou o he bi umen.
Figu e 18 – (a) 8 mm pla e; (b) 25 mm pla e
The cha ac e iza ion o he heological p ope ies o he bi umen is gi en by di e en p ope ies, as
p e iously s a ed. One o hese p ope ies is he phase angle, δ, which p o ides a ela i e indica ion o
he iscous and elas ic beha iou s o he binde , wi h alues be ween 0°, o a ully elas ic ma e ial, and
90°, o a o al iscous binde . A in e media e empe a u es ( o example, a 19 ºC), asphal binde s a e
said o be iscoelas ic wi h a phase angle nea 45° (Asphal Ins i u e, 2019). Ano he main p ope y is
he complex shea modulus, G*, which measu es he s i ness o he asphal binde , and can be
unde s ood as he complex sum o he elas ic and iscous componen s o he ma e ial, which a e
ep esen ed by he elas ic modulus, G’, and he iscous modulus, G’’ (Domínguez, 2018).
Elas ic eco e y
The elas ic eco e y is a measu e o he e u n capaci y o an asphal binde a e an in e up ion o
speci ied mechanical s ess. The me hod ha allows his measu emen is also named elas ic eco e y
me hod and is essen ially a p ocedu e pe o med o de e mine he elas ic eco e y o asphal binde s in
a duc ilome e a a speci ic es empe a u e ( ypically 25 °C o 10 °C al hough o he empe a u es can
be used). I is especially applicable o PMBs modi ied wi h he moplas ic elas ome s, bu can also be
used wi h o he asphal binde s e en hough hese will gene a e a small eco e y. This p ocess is ca ied
ou acco ding o he Eu opean S anda d EN 13398 (Bi umen and bi uminous binde s - De e mina ion o
he elas ic eco e y o modi ied bi umen). Samples mus be s e ched a a speed o 50 mm/min a he
a)
b
)

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
39
s ipula ed empe a u e un il hey each a p ede e mined elonga ion o 200 mm, in o de o de e mine he
elas ic eco e y. Then, hey a e cu in he cen al sec ion and, a e 30 minu es, he dis ance eco e ed
be ween he wo hal es is measu ed, as exempli ied in Figu e 19.
Figu e 19 – Elas ic eco e y measu emen
The wa e ba h shall be empe a u e con olled, capable o main aining he specimen and he a achmen
de ice a he speci ied empe a u e h oughou he es o an accu acy o ± 0,5 °C. The es mus be
ca ied ou on a leas wo specimens in pa allel, which should be condi ioned in he wa e ba h a he
es empe a u e o no less han 90 minu es. The mould used o ob ain hese specimens is he one
shown in Figu e 20. The es samples we e p epa ed ollowing he Eu opean S anda d EN 12594
(Bi umen and bi uminous binde s. P epa a ion o es samples), as speci ied in EN 13398.
Figu e 20 – Elas ic eco e y mould
The inal elas ic eco e y alue RE is gi en by Equa ion 2.
𝑅𝑅𝐸𝐸 (%)=𝑑𝑑
𝐿𝐿×100
(2)
whe e,
d = dis ance be ween hal - h eads, in mm;
L = s e ching leng h, in mm ( o a p ema u e b eak due o b i leness, L is he elonga ion a b eak).
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
40
In he cu en wo k, his me hod was pe o med a wo es empe a u es, +5 °C and +20 °C, o bo h
polyme -modi ied binde s, PMB25 and PMB50.
Fo ce duc ili y me hod
Duc ili y is he abili y o a ma e ial o unde go a isible endu ing de o ma ion h ough elonga ion
(dec easing o c oss-sec ion a ea) wi hou b eaking. I exp esses he ex en o which he ma e ial can be
plas ically de o med wi hou ac u e. In p ac ical e ms, i is de ined as he dis ance, in millime es, o
which a s anda d sample o he ma e ial will be s e ched wi hou b eaking. The me hod was pe o med
acco ding o he Eu opean S anda d EN 13589 (Bi umen and bi uminous binde s - De e mina ion o he
ensile p ope ies o modi ied bi umen by he o ce duc ili y me hod). The asphal binde sample mus be
s e ched 50 mm/min in a duc ilome e a he s ipula ed empe a u e un il i eaches a p ede e mined
elonga ion o 400 mm o un il i b eaks, as shown in Figu e 21.
Figu e 21 – Elonga ion o o ce duc ili y specimens
The wa e ba h shall be empe a u e con olled, capable o main aining he specimen and he a achmen
de ice a he speci ied empe a u e h oughou he es o an accu acy o ± 0.5 °C. The es mus be
ca ied ou on a leas wo specimens in pa allel, which should be condi ioned in he wa e ba h a he
es empe a u e o no less han 90 minu es. The mould used o ob ain hese specimens is he one
shown in Figu e 22. The es samples we e p epa ed ollowing he Eu opean S anda d EN 12594, as
speci ied in EN 13589. The o ce duc ili y is gi en by he de o ma ion ene gy, Ei by using Equa ion 3.
𝐸𝐸=� 𝐹𝐹(𝑥𝑥)𝑑𝑑𝑥𝑥
𝐿𝐿2
𝐿𝐿1 =∆𝐿𝐿× (𝐹𝐹0
2+𝐹𝐹𝑛𝑛
2+�𝐹𝐹𝑖𝑖
𝑛𝑛−1
1
)
(3)
whe e,
L1 = leng h a 0.200 m elonga ion;
L2 = leng h a 0.400 m elonga ion o he leng h a b eak;
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
41
ΔL = inc emen al leng h be ween o ce de e mina ions; no mally 0.005 m;
F0 = o ce a 0.200 m elonga ion;
Fi = o ce a (L1 + i × ΔL);
Fn = o ce a b eak o 0.400 m elonga ion;
n = o al amoun o o ce alues used in Equa ion 3 (n = (L2 – L1) / ΔL), i needed ounded o he nea es
in ege alue.
Figu e 22 – Fo ce duc ili y mould
The cohesion ene gy is also a p ope y ob ained om his p ocedu e and is gi en by Equa ion 4.
𝐶𝐶𝐶𝐶ℎ𝑅𝑅𝑅𝑅𝑅𝑅𝐶𝐶𝑅𝑅 𝑅𝑅𝑅𝑅𝑅𝑅𝑒𝑒𝑒𝑒𝑒𝑒=𝐸𝐸𝑖𝑖
𝑅𝑅𝑒𝑒𝐶𝐶𝑅𝑅𝑅𝑅 𝑅𝑅𝑅𝑅𝑅𝑅𝑠𝑠𝑅𝑅𝐶𝐶𝑅𝑅 (𝑚𝑚𝑚𝑚
2
)
(4)
Cohesion is a measu e o he ensile s ess equi ed o b eak he bond be ween molecules o he asphal
binde . The inhe en s eng h, enaci y and oughness o he asphal binde s a e imp o ed by modi ica ion
wi h he moplas ic polyme s and ubbe c umbs. Hence, highe ensile s ess is equi ed o b eak he
molecula bonds o modi ied binde s and cause ailu e compa ed wi h lowe ensile s ess equi ed o
b eak he bonds o con en ional binde s (SABITA, 2015).
This me hod was pe o med a wo es empe a u es, +5 °C and +20 °C, o bo h polyme -modi ied
binde s s udied in his wo k (PMB25 and PMB50).
3.5. Asphal mix u es
A e pe o ming he se e al labo a o y es s o cha ac e ize in de ail bo h he agg ega es and he asphal
binde s, he asphal mix u es we e hen selec ed and p oduced.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
42
The asphal mix u es ollow he indica ions p o ided by he Eu opean S anda ds EN 13108-1 (Bi uminous
mix u es - Ma e ial speci ica ions - Pa 1: Asphal Conc e e) and EN 13108-5 (Bi uminous mix u es -
Ma e ial speci ica ions - Pa 5: S one Mas ic Asphal ).
The s anda d EN 13108-5 speci ies he equi emen s o mix u es o he g oup S one Mas ic Asphal o
use on oads, ai ields and o he a icked a eas. Al hough he speci ica ion o he SMA mix u e p o ided
in his Eu opean S anda d has ye o be ansposed o Po uguese no ms, success ul mix designs ha e
al eady been applied by
In aes u u as de Po ugal, S.A.
, he s a e-owned company in cha ge o
managing he ail and oad in as uc u e.
The Eu opean S anda d p o ides he designa ion o he mix u e as ollows: SMA D Binde , whe e SMA is
S one Mas ic Asphal , D is he uppe sie e size, and Binde e e s o he binde g ade o class in he inal
p oduc . In his s udy, a S one Mas ic Asphal mix u e wi h a maximum agg ega e size o 11 mm was
selec ed o a su ace cou se, o bo h asphal mix u es, and he modi ied bi umens pene a ion g ades
will be accessed u he ahead, bu he base bi umen will be used he e as an exempli ica ion. In ha
example, he designa ion o he asphal mix u e will be SMA 11 50/70, wi h he 50/70 being eplaced
by he ob ained pene a ion g ades o each polyme -modi ied bi umen.
S one Mas ic Asphal o SMA o sho , is a ype o g aded asphal mix u e ha consis s o a high
concen a ion o coa se agg ega e held oge he by a ma ix o mine al ille s and s abilize s and a hick
bi umen ilm (Sheka
e al.
, 2018).
The inal composi ion o bo h asphal mix u es shall be comp ised o 6% PMB and 94% agg ega es by
weigh o he mix u e. E en hough he e is no speci ic s anda d o de e mine a minimum o maximum
con en o he polyme o use when i conce ns modi ied bi umens, he selec ed pe cen age was based
on p e ious esea ch by many di e en au ho s such as Shinoha a
e al.
(2011), Fe nandes
e al.
(2016),
Saboo and Kuma (2016), To es (2014) and Po o
e al.
(2019), among many o he s.
Asphal mix u es p oduc ion
A e he selec ion and p oduc ion o he polyme -modi ied bi umens and subsequen labo a o y analysis
o unde s and u he hei cha ac e is ics as well as he inal g ading composi ion o he agg ega es, he
condi ions a e me o p oduce he inal asphal mix u es. This p ocess will en ail wo pa s: a i s phase,
o mix u e p oduc ion, and a second phase, o slabs compac ion. These asphal mix u es o he su ace
cou se we e p epa ed using h ee asphal binde s included in his s udy, using he same agg ega es.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
49
sa u a ed, a e which hey a e again weighed while in wa e . They a e hen aken om he wa e , and
hei su aces a e d ied wi h a damp Chamois so hey can be weighed again. The me hod C in ol es
again weighing he specimens d y, sealing he specimen wi h a ilm (so no oids a e pene a ed by wa e ,
and no o he oids a e included be ween he seal and he su ace), and weighing his sealed specimen,
subme ging i in wa e and weighing i in wa e . Finally, he me hod D comp ises de e mining he
dimensions o he specimen and subsequen ly measu ing he co esponding mass. Du ing his esea ch
wo k, all me hods desc ibed in he Eu opean S anda d we e used o ob ain he bulk densi y o each
specimen and p o ide a compa ison be ween hem, excep me hod C, which was only u ilized on h ee
specimens o logis ic easons. Figu e 29 shows he appa a us used o weighing he specimens in wa e .
Figu e 29 – Bulk densi y weighing appa a us
Equa ions 7 o 10 used in each me hod o bulk densi y de e mina ion a e p esen ed below.
• P ocedu e A:
𝜌𝜌𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 =𝑚𝑚1
𝑚𝑚1−𝑚𝑚2×𝜌𝜌𝑤𝑤
(7)
• P ocedu e B:
𝜌𝜌𝑏𝑏𝑏𝑏𝑏𝑏𝑏𝑏 =𝑚𝑚1
𝑚𝑚3−𝑚𝑚2×𝜌𝜌𝑤𝑤
(8)
whe e,
ρbd y = bulk densi y d y, in kilog ams pe cubic me e (kg/m3);

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
50
ρbssd = bulk densi y (SSD), in kilog ams pe cubic me e (kg/m3);
m1 = mass o he d y specimen, in g ams (g);
m2 = mass o he specimen in wa e , in g ams (g);
m3 = mass o he sa u a ed su ace-d ied specimen, in g ams (g);
ρw = densi y o he wa e a es empe a u e, in kilog am pe cubic me e (kg/m3).
• P ocedu e C:
𝜌𝜌𝑏𝑏𝑏𝑏𝑏𝑏𝑎𝑎 =𝑚𝑚1
(𝑚𝑚2−𝑚𝑚3/𝜌𝜌𝑤𝑤)−(𝑚𝑚2−𝑚𝑚1/𝜌𝜌𝑏𝑏𝑚𝑚)
(9)
whe e,
ρbsea = bulk densi y sealed, in kilog ams pe cubic me e (kg/m3);
m1 = mass o he d y specimen, in g ams (g);
m2 = mass o he sealed specimen d y, in g ams (g);
m3 = mass o he sealed specimen in wa e , in g ams (g);
ρw = densi y o he wa e a es empe a u e, in kilog am pe cubic me e (kg/m3).
ρsm = densi y o he sealing ma e ial a es empe a u e, in kilog ams pe cubic me e (kg/m3);
• P ocedu e D:
𝜌𝜌𝑏𝑏,𝑏𝑏𝑖𝑖𝑚𝑚 =𝑚𝑚1
ℎ×𝑅𝑅×𝑤𝑤×103
(10)
whe e,
ρb,dim = bulk densi y o he specimen, in kilog ams pe cubic me e (kg/m3);
m1 = mass o he d y specimen, in g ams (g);
h = heigh o he specimen, in millime es (mm);
l = leng h o he specimen, in millime es (mm);
w = wid h o he specimen, in millime es (mm).
3.6. Mechanical me hods o cha ac e iza ion o he asphal mix u es
The me hods by which he mechanical p ope ies and cha ac e is ics o asphal mix u es a e e alua ed
a e based on he Eu opean S anda d EN 12697-46 (Bi uminous mix u es - Tes me hods o ho mix
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
51
asphal - Pa 46: Low empe a u e c acking and p ope ies by uniaxial ension es ). This s anda d (CEN,
2012) de ails he de ices and condi ions equi ed o e alua e an asphal mix u e unde low- empe a u e
condi ions and is, he e o e, undamen al o he analysis ca ied ou du ing his esea ch wo k.
Bonding agen
The bonding agen is applied o he mechanical es s, and i wo ks as a glue be ween he pla es and he
specimen o hold i in place and allow he ensile es s o be pe o med.
The adop ed bonding agen is a wo-pa , as cu ing, s eel- illed epoxy pu y by De con. Acco ding o i s
echnical shee , i ha dens one hou a e mixing and applica ion and ully cu es in 16 hou s a 21 °C.
The wo pa s consis o a ha dene and a esin, shown in Figu e 30.
Figu e 30 – (a) Bonding agen ; (b) Mixing boa d and spa ula
The mixing should be made on a mixing boa d using a spa ula and o bes esul s a oom empe a u e
o a ound 21 °C; i should be ho oughly mixed by adding he ha dene o he esin in a a io o 1:1 o
one minu e since i only has a 5-minu e po li e.
Tes ing de ices and o he condi ions
The mechanical me hods used o cha ac e ize he specimens equi e an appa a us consis ing o a
he mos a ic chambe wi h o ced ai ci cula ion in which he specimen can be condi ioned and in which
he es can be pe o med. The chambe empe a u e mus be main ained du ing he es s, be ween -40
and 30 °C (wi h an accu acy o ± 0.5 °C). The he mos a ic chambe mus be capable o enabling a
empe a u e a e in he co e o he specimen o 10 °C/h.
a) b)
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
52
Inside his he mos a ic chambe , i mus be loca ed a loading de ice able o gene a e mo emen s wi h
an accu acy o 0.1 µm. The specimen should be connec ed o he loading de ice by wo gimbal
suspensions o a oid adial and ans e sal o ces as well as momen s in he es specimen.
The de ice u ilized was he se o-con olled uni e sal es ing machine CS7400S wi h ixed endpla es. This
equipmen has a load cell connec ed o he e ical ac ua o wi h a capaci y o 22 kN, being pa icula ly
sui able o small specimens. Howe e , i does no mee he en i e empe a u e equi emen s since i is
only able o main ain a minimum low- empe a u e o app oxima ely -20 °C, unde he cu en se
condi ions, which can be a challenge o some o he es s. The de ice is p esen ed in Figu e 31, as well
as i s he mos a ic chambe .
Figu e 31 – (a) CS7400S de ice; (b) In e io o he chambe
As p e iously men ioned, he dis ance be ween pla es is limi ed o 160 mm. A de ail o he loading de ice
is shown in Figu e 32. The es ing de ice o he uniaxial cyclic ensile s ess es (UCTST) equi es some
special condi ions in addi ion o he ones o all o he mechanical es s. The loading de ice mus be a
dynamic es ing de ice consis ing o a bending- esis an load ame wi h a leas wo suppo s, a
empe a u e chambe , a hyd aulic sys em and a con ol uni con olling o ce o displacemen . The es ing
de ice mus be capable o applying a dynamic load o a leas he applied es equency wi h an accu acy
o 0.1 Hz along he longi udinal axis o he es specimen. The load should be sinusoidal wi h o wi hou
a es pe iod. The same se o-con olled uni e sal es ing machine CS7400S was u ilized o he UCTST
since i is capable o mee ing all he equi emen s es ablished by he s anda d.
a)
b)
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
53
Figu e 32 – De ail o he loading de ice
Acco ding o he S anda d EN 12697-46, a leas h ee specimens mus be es ed o each asphal
ma e ial and es condi ion ( empe a u e and le el o s ess) combina ion. Ini ially, he logis ics we e in
place o mee his equi emen . Howe e , so many obs acles appea ed du ing he expe imen s, ha his
condi ion was no me o all es s.
In o de o glue he wo adap e s o he specimen, he s anda d sugges s he use o a moun ing bench
whe e he wo adap e s can be moun ed e ically, and he specimen adjus ed ho izon ally o hem
h ough heigh -adjus able suppo . This suppo is used o c ea e a posi i e cen ic connec ion be ween
he es specimen and he wo connec o s. The e was no moun ing bench a ailable, bu a e se e al
di e en con igu a ions in di e en de ices, a simila de ice was a anged, whe e he adap e s a e
moun ed ho izon ally, and he specimen is glued e ically o hem. The moun ing de ice needs o hold
he op connec o in place o a oid de o ma ions o he specimen due o he weigh o he op pla e.
The es sys em mus be equipped wi h a sys em moni o ing he load ac ing on he es specimen wi h a
load cell ha shall ha e a minimum measu ing ange o ±15 kN wi h an accu acy o ±10 N. The
displacemen ansduce s shall ha e a minimum measu ing ange o ±2.5 mm wi h an accu acy o
±5 µm. Bo h he load cell and he wo chosen displacemen ansduce s, Linea Va iable Di e en ial
T ans o me (LVDT), mee hese equi emen s, ha ing a hi d in e nal ansduce in he es ing machine
CS7400S, which also mee s he condi ions. Figu e 33 p esen s he inal sys em used in he es s.
160 mm
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
54
Figu e 33 – Specimen glued o connec o s and measu ing de ices (LVDT)
The specimen will be ins alled in o he es de ice by joining he adap e s wi h he load de ice. The
specimen mus be s abilized a he es empe a u e T (o T0, in case o TSRST) be o e s a ing he es
o an adequa e du a ion wi hou applying any load. Du ing he condi ioning phase, he closed-loop con ol
o he es de ice mus ensu e ha he specimen is no subjec ed o any loads. The du a ion o his phase
depends on he specimen size and he ma e ial es ed, bu i mus ensu e ha he empe a u e in he
specimen is cons an wi hin ±1 °C o he es empe a u e o no less han 10 minu es. A dummy
specimen is placed nea he specimen being es ed o ha e i ica ion. This dummy specimen consis s
o a specimen o he same asphal mix u e as he es ed specimen, bu wi h a empe a u e measu ing
de ice ins alled in i s co e o emula e he empe a u e o he es ed specimen. Figu e 34 p esen s one o
he dummy specimens u ilized.
Figu e 34 – Dummy specimen used o empe a u e con ol

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
55
Uniaxial ension s ess es
In he uniaxial ension s ess es (UTST), a specimen is pulled wi h a cons an s ain a e a a cons an
empe a u e un il ailu e. Resul s o he UTST a e he maximum s ess ( ensile s eng h) β (T), and he
co esponding ensile ailu e s ain ε ailu e (T) a he es empe a u e T. The p inciple o his es me hod is
shown in Figu e 35. As p e iously s a ed, he specimens a e subjec ed o a s ain-dependen es on ime,
which is based on he ini ial leng h. The cons ain s ain a e (dε) is equal o 0.625 ± 0.025 %/min.
Figu e 35 – Tes p inciple o UTST
Fo each empe a u e, h ee specimens we e es ed, in o de o ha e a mo e p ecise ange o esul s.
The esul s ob ained om his mechanical es a e he ensile s eng h β (MPa) and he ailu e s ain ε ailu e
a each empe a u e. These a e espec i ely calcula ed acco ding o Equa ions 11 and 12.
𝛽𝛽𝑠𝑠(𝑀𝑀𝑃𝑃𝑀𝑀)=𝐹𝐹𝑓𝑓𝑎𝑎𝑖𝑖𝑓𝑓𝑓𝑓𝑏𝑏𝑏𝑏(𝑁𝑁)
𝐴𝐴(𝑚𝑚𝑚𝑚2)
(11)
𝜀𝜀𝑓𝑓𝑎𝑎𝑖𝑖𝑓𝑓𝑓𝑓𝑏𝑏𝑏𝑏(‰) = 𝜀𝜀(𝑚𝑚𝑚𝑚)
𝐿𝐿(𝑚𝑚𝑚𝑚)×1000
(12)
whe e,
β = ensile s eng h in MPa;
F ailu e = measu ed ension o ce a ailu e in N;
A = ini ial c oss-sec ion in mm2;
ε ailu e = ailu e s ain in pe millage (‰);
ε = measu ed s ain a he ailu e ime in mm;
L = ini ial leng h in mm.
The mal s ess es ained specimen es
In he he mal s ess es ained specimen es (TSRST), he specimen, whose leng h is held cons an , is
subjec ed o a dec ease in empe a u e wi h a cons an empe a u e a e. C yogenic s ess is buil up in
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
56
he specimen, due o he p ohibi ed he mal sh inkage. This p ocedu e pe mi s ob aining esul s
conce ning he p og ession o he c yogenic s ess o e he empe a u e σc y (T), and he ailu e s ess
σc y, ailu e a he ailu e empe a u e T ailu e. The ailu e s ess is equi alen o he s eng h o he specimen a
he ailu e empe a u e (Pszczola and Szydlowski, 2018).
This es was pe o med wi h h ee di e en a es o dec ease in empe a u e in o de o obse e he
e ec his cooling a e has on TSRST esul s and, indi ec ly, on he ensile s eng h ese e analysis,
explained u he ahead. The s a ing empe a u e, T0 = +20 °C, ecommended o ini ia e he es , was
obse ed, as well as he cooling a e indica ed by he S anda d, dT = -10 °C/h. Acco ding o Pszczola
e
al.
(2019b) he cooling a e a ec s he expe imen al measu emen s in his es signi ican ly. To de e mine
his e ec , wo addi ional cooling a es we e selec ed: dT = -2 °C/h and dT = -5 °C/h. This selec ion was
made based on he esea ch made by Pszczola
e al.
(2016) in which he pa emen empe a u es a e
analysed in a coun y wi h a clima e ep esen a i e o low- empe a u e condi ions. In ha s udy, i was
obse ed ha a cooling a e o -2 °C/h has a p obabili y o occu ence o 99%, which can be a good
ep esen a ion o he ypical low- empe a u e condi ions du ing a conside able po ion o he win e .
Howe e , and al hough he p obabili y o occu ence o cooling a es lowe han -3 °C/h is less han 1%,
i is signi ican o no ice ha low- empe a u e c acks a e ini ia ed by a combina ion o he mos ad e se
ac o s. Then, he selec ed -5 °C/h cooling a e can be an adequa e ep esen a ion o mo e ex eme
condi ions, ha e en hough may happen mo e in equen ly, hei e ec can be mo e se e e on he
pa emen when hey occu . The p inciple o his es me hod is shown in Figu e 36.
Figu e 36 – Tes p inciple o TSRST
Based on UTST and TSRST es s, and hei esul s, i is possible o de e mine he ension s eng h ese e,
Δβ (T), which he mix u e can suppo unde ex e nal loads in addi ion o he low- empe a u e he mal
s esses (Figu e 37). I is calcula ed as he di e ence be ween he ensile s eng h, β (T) – ob ained om
he UTST as a empe a u e/ ensile s eng h diag am using a cubic spline unc ion – and he c yogenic
s ess σc y(T) – ob ained om he TSRST a he same empe a u e T using he Equa ion 13.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
57
∆𝛽𝛽𝑡𝑡(𝑇𝑇)=𝛽𝛽𝑡𝑡(𝑇𝑇)−𝜎𝜎𝑐𝑐𝑏𝑏𝑏𝑏(𝑇𝑇)
(13)
whe e,
Δβ (T) = ensile s eng h ese e in MPa;
β (T) = ensile s eng h in MPa;
σc y(T) = c yogenic ( he mal) s ess in MPa.
Figu e 37 – P inciple o he ensile s eng h ese e
Relaxa ion es
In he elaxa ion es (RT), he specimen is subjec ed o a spon aneous s ain ε, which is held on a
cons an le el. The dec ease o ension s ess by elaxa ion o e he es ing ime is moni o ed. The ini ial
s ess should no be highe han 75% o he ensile s eng h β , ob ained om he UTST es s. The
elaxa ion ime is he ime when he s ess is educed o 36.8 ± 0.1% (1/e = 1/2.718 = 0.368) o i s
ini ial alue. The esul s a e he ime o elaxa ion el, and he emaining ension s ess σ em a e he es
has ended. The p inciple o his es me hod is shown in Figu e 38.
Figu e 38 – Tes p inciple o RT
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
58
Tensile c eep es
In he ensile c eep es (TCT), he specimen is subjec ed o a cons an ension s ess σ a a cons an
empe a u e T, du ing which he p og ession o he s ain ε is measu ed. A e a gi en ime, he s ess is
wi hd awn, and he eg ession o he s ain is measu ed. Rheological pa ame e s desc ibing he elas ic
and iscous p ope ies o he asphal can be de e mined by in e p e ing he s ain measu emen s. I is
ecommended o hold he cons an load o 8 hou s and eco d he eg ession a e unloading o an
addi ional 2 hou s.
Table 8, p esen ed in S anda d EN 12697-46, sugges s he es empe a u es and sui able s ess le els
as a p opo ion o he ensile s eng h ob ained in UTST. Besides, and since one o he selec ed es
empe a u es is -20 °C, he co esponding s ess le el p opo ion was in e pola ed be ween he adjacen
alues. The p inciple o his es me hod is shown in Figu e 39.
Table 8 – Recommended es condi ions o TCT
Tempe a u e (°C) The p opo ion o
β
(T) (%)
-25 50
-20 43
-10 30
+5 10
+20 5
Figu e 39 – Tes p inciple o TCT
Uniaxial cyclic ensile s ess es
In he uniaxial cyclic ension s ess es (UCTST), a specimen is subjec ed o cyclic ensile s ess which is
cha ac e ised by sinusoidal s ess, shown in Figu e 40, o simula e he dynamic loading condi ion by
a ic in combina ion wi h cons an s ess, which symbolises he c yogenic s ess. Du ing he es , he
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
65
Figu e 45 – Elas ic modulus G’ o asphal binde s, in kPa
Figu e 46 – Viscous modulus G" o asphal binde s, in kPa
One o he main pa ame e s gi en by he DSR es is he complex shea modulus, G*, shown in Figu e
44. I can be unde s ood as he complex sum o he elas ic and iscous componen s o he bi umen,
which a e ep esen ed by he elas ic modulus, G’, and he iscous modulus, G’’, shown in Figu es 45
and 46, espec i ely.
1.E-02
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
10 20 30 40 50 60 70 80 90
G' (kPa)
Tempe a u e (°C)
50/70
PMB25
PMB50
1.E-01
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
10 20 30 40 50 60 70 80 90
G'' (kPa)
Tempe a u e (°C)
50/70
PMB25
PMB50

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
66
In all e alua ed bi umens, i can be obse ed a dec ease in he elas ic, G’, and iscous modulus, G’’, wi h
inc easing empe a u e, which in u n ansla es in a dec ease in he complex shea modulus, G*. This
pa e n indica es he linea dependence o log G* wi h empe a u e.
The analysis o he complex modulus shows ha bo h polyme -modi ied binde s ha e iden ical beha iou
conce ning his pa ame e , as bo h cu es align wi h each o he almos pe ec ly. I can also be obse ed
ha he PMB p esen a highe s i ness o e he ange o analysed empe a u es in compa ison wi h he
base bi umen 50/70. The di e ences a e e en highe a high empe a u es, showing he excellen
pe o mance o PMBs a high empe a u es. In conclusion, he SBS polyme used in he modi ica ion o
bo h binde s signi ican ly inc eased he complex modulus o he base bi umen.
Figu e 47 – Phase angle (δ) o asphal binde s, in deg ees (°)
The phase angle, δ (°), p o ides a ela i e indica ion o he iscous and elas ic beha iou s o he binde ,
and his angle a ies be ween 0°, o an u e ly elas ic ma e ial, and 90°, o an u e ly iscous asphal
binde . A in e media e empe a u es, such as 19 °C, asphal binde s a e said o be iscoelas ic wi h a
phase angle nea 45° (Asphal Ins i u e, 2019).
Fo he empe a u e o 20 °C, he PMB25 has he lowes alue, albei no conside ably di e en om he
o he bi umens, which shows ha his bi umen p esen s a sligh ly less iscous componen a his
empe a u e in compa ison wi h he o he binde s. This esul could indica e ha PMB50 ha e a sligh ly
45
50
55
60
65
70
75
80
85
90
10 20 30 40 50 60 70 80 90
Phase angle (°)
Tempe a u e (°C)
50/70
PMB25
PMB50
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
67
be e capaci y o esis a igue a low empe a u es han PMB25, al hough his si ua ion should be u he
e alua ed because he di e ence be ween bo h phase angles is only 6°. All he h ee bi umens p esen
phase angle cu es abo e he 45° e e ence o iscoelas ic ma e ial and as such can be p esen ed as
ha ing a mo e iscous, a he han a mo e elas ic beha iou .
When he empe a u e inc eases, bo h PMBs end o ha e simila phase angle alues. An inc ease in he
phase angle alues o PMBs can be seen un il hey each a maximum alue o 67° a he empe a u e o
46 °C, which indica es an inc ease in he iscous beha iou un il ha empe a u e. The cu a u e in e s
a e 46 °C, and bo h cu es beha e almos he same, wi h he iscous na u e o PMBs dec easing as
he empe a u e inc eases.
The base bi umen 50/70 p esen s an almos pa allel beha iou o he PMBs, albei wi h highe alues o
he phase angle and a maximum alue o 86° ob ained a highe empe a u es (60 °C).
This pa allelism be ween he base bi umen and he PMBs cu es shows he con ibu ion o he base
bi umen in he PMBs beha iou . By con as , and obse ing he di e ences be ween he cu es, i can be
seen he e ec he polyme has on he base bi umen, gene ally lowe ing i s iscosi y and adding a mo e
elas ic componen o he PMB. The smoo h o undula ing change in he phase angle o e a b oad
empe a u e ange can be p ima ily a ibu ed o he addi ion o modi ie s (Ai ey, 2003). This phenomenon
imp o es he esis ance o asphal pa emen s o pe manen de o ma ion.
The combina ion o a highe complex modulus and a lowe phase angle a highe empe a u es o he
PMB in compa ison o he base bi umen 50/70 can be a good indica ion o he be e pe o mance o
he co esponding mix u es o esis pe manen de o ma ion.
The a e age esul s o he es s pe o med in wo samples o e alua e iscosi y o bo h PMBs and he
base bi umen 50/70 a di e en empe a u es a e illus a ed in Figu es 48 and 49.
Acco ding o Van Ams e dam (2000), he iscosi y is a measu e o a liquid low a e and i s consis ency.
Abo e 100 °C, he bi umen ac s almos en i ely as a iscous luid, and so his p ocedu e cha ac e izes
he bi umen s i ness by de e mining i s heological p ope ies. The iscosi y measu ed be ween 100 °C
and 180 °C pe mi s he de e mina ion o he mixing and compac ion empe a u es, aking in o accoun
he ype o binde . The concep behind ha de e mina ion is ha he hea ed asphal binde should be
liquid enough o adequa ely coa he agg ega es du ing he mixing phase and being wo kable enough
du ing he compac ion o he mix u e.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
68
Figu e 48 – Dynamic iscosi y esul s o he binde s o high empe a u es, in cP
Figu e 49 – Dynamic iscosi y esul s o he binde s o all empe a u es, in cP
The esul s show he highe iscosi y o he modi ied binde s in compa ison wi h he base bi umen 50/70
o e he whole ange o empe a u es. Bo h PMB25 and PMB50 ha e inc edibly simila alues o iscosi y,
only wi h a sligh ly lowe iscosi y o PMB50 a speci ic empe a u es. Thus, inco po a ing 2.5% SBS in
nea bi umen changes he iscosi y adically, bu he addi ion o mo e SBS ba ely changes he iscosi y.
1E+02
1E+03
1E+04
1E+05
90 110 130 150 170 190
Dynamic Viscosi y (cP)
Tempe a u e (°C)
50/70 PMB25 PMB50 3000 cP 135 °C
1E+02
1E+03
1E+04
1E+05
1E+06
1E+07
1E+08
1E+09
050 100 150 200
Dynamic Viscosi y (cP)
Tempe a u e (
°
C)
50/70
PMB25
PMB50
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
69
Unmodi ied bi umen should ha e iscosi ies o abou 170 ± 20 cP o mixing and 280 ± 30 cP o
compac ion (Zaniewski and Pumph ey, 2004). The iscosi ies o bi umen 50/70 shown in Figu e 48 poin
ou ha he empe a u e o mixing should be no highe han 160 °C and o compac ion below 145 °C.
Acco ding o Ala aş and Yilmaz (2017), in o de o he binde s o ul il he wo kabili y equi emen s, hey
should no exceed iscosi ies o 3000 cP (3 Pa.s) a 135 °C. This c i e ion is ul illed as can be obse ed
in he g aph om Figu e 48. Bo h samples o he PMB, as well as he base bi umen, e i y his wo kabili y
equi emen , ha ing alues below he maximum 3000 cP a 135 °C.
Shenoy (2001) discusses ha a p e e able mixing empe a u e o an SBS based PMB can ange om
163 o 180 °C o sa is y he ollowing c i e ia: i) he empe a u e should be high enough o ensu e he
binde shows good luidi y in o de o coa he agg ega e du ing mixing uni o mly and he inal mix
discha ge does no cool o below 85 °C du ing laying and compac ion; ii) he empe a u e should be low
enough o ensu e ha he polyme in he modi ied binde does no deg ade, and accele a ed ha dening
o he asphal in he modi ied binde does no ake place due o exposu e o hea and ai , and; iii) he
empe a u e should be app op ia e o ensu e good quali y o mixing. Ano he ecommenda ion made by
he Asphal Ins i u e (2020) e e s ha he labo a o y mixing empe a u es should no exceed 177 °C.
Špaček
e al.
(2017) also poin ou ha a mix u e wi h modi ied asphal binde s equi es highe
empe a u es du ing compac ion in compa ison wi h a mix u e wi h con en ional bi umen 50/70.
Consequen ly, his will esul in achie ing di e en alues o bulk densi y and po osi y. A simila analysis
was pe o med by To h
e al.
(2016), whe e a high empe a u e o compac ion was de e mined acco ding
o he equi iscous p inciple, a p inciple p oposed by he Japan Modi ied Asphal Associa ion. Finally,
Almusawi
e al.
(2019) e i y empe a u es o 177 °C o compac ion and 189 °C o mixing by he
equi iscous me hod in he ASTM D2493 S anda d, o a 5% SBS modi ied binde . Thus, he selec ed
empe a u e o mixing and compac ion was 170 °C aking in o accoun all p e ious sugges ions.
Elas ic eco e y
As p e iously s a ed, he elas ic eco e y es was pe o med o bo h PMB25 and PMB50 a wo es
empe a u es, +5 °C and +20 °C. The ecommended es empe a u es, acco ding o EN 13398, a e
ypically 25 °C o 10 °C e en hough o he empe a u es can be used in o de o a end o speci ic local
condi ions. In his low- empe a u e s udy o asphal mix u es, he mechanical es s o SMA mix u es will
be made a +5 °C and +20 °C empe a u es, jus i ying he selec ion o he same empe a u es o his
es o he PMBs. The esul s ob ained o he inal elas ic eco e y alue RE a e shown in Table 12.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
70
Table 12 – Resul s o elas ic eco e y (RE) o PMBs
Specimen
RE (%)
+5 °C +20 °C
PMB25 PMB50 PMB25 PMB50
ER1 65% 52% 98% 95%
ER2 64% 51% 98% 95%
ER3 67% 52% 98% 96%
mean alue 65% 51% 98% 95%
s anda d de ia ion 1% 1% 0% 0%
coe icien o a ia ion 2% 1% 0% 0%
The minimum c i e ion o a p ede e mined elonga ion o 200 mm was eached a he empe a u e o
+20 °C o bo h PMBs, bu a he empe a u e o +5 °C h ee samples b oke p ema u ely. The p ocedu e
de ailed in he s anda d o b i le ailu es was ollowed in hose si ua ions. Bo h binde s (PMB25 and
PMB50) beha ed ema kedly well a he es empe a u e o +20 °C, wi h almos 100% eco e y, al hough
he PMB25 p esen ed sligh ly be e esul s wi h a mean alue o 98%, sligh ly highe han 95% o PMB50.
Con e sely, o he es empe a u e o +5 °C, bo h binde s p esen ed lowe alues o elas ic eco e y,
as can be expec ed gi en he b i le beha iou and he high s i ness o asphal binde s a lowe
empe a u es in compa ison wi h highe ones. A his empe a u e, PMB25 p esen ed, again, a highe
mean alue o elas ic eco e y, 65%, bu his ime wi h some no iceable di e ence o he PMB50, p ecisely
14% highe han he 51% mean alue o PMB50.
The elonga ion e sus o ce was also eco ded du ing he elas ic eco e y es , and hose esul s a e
shown in Figu es 50 and 51.
PMB50 p esen s a mo e igid and b i le beha iou han PMB25, p esen ing highe ene gy equi emen
o be elonga ed and b eaking a lowe elonga ion alues when es ed a +5 °C empe a u e. I is also
no iceable he di e ence in ene gy equi emen be ween bo h es ed empe a u es since he +5 °C
empe a u e es s equi e o e en imes he amoun o ene gy needed o achie e he same ype o
beha iou when es s a e pe o med a +20 °C empe a u e.
O e all, bo h PMBs p esen ed an excellen elas ic eco e y beha iou , which may indica e a po en ial
good c acking pe o mance a low empe a u e (Zhang
e al.
, 2019).

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
71
Figu e 50 – Elas ic eco e y o ce o PMBs a +5 °C (mean alues)
Figu e 51 – Elas ic eco e y o ce o PMBs a +20 °C (mean alues)
Acco ding o he Eu opean S anda d EN 14023 (Bi umen and bi uminous binde s. Speci ica ion
amewo k o polyme -modi ied bi umens), bo h PMBs can be included in class 2 (≥ 80%) o elas ic
eco e y a +25 °C. E en hough he es s we e pe o med a +20 °C, i is p edic able ha he beha iou
a +25 °C would be simila o e en be e .
As o he o he empe a u e e lec ed in he s anda d (+10 °C), a linea in e pola ion was pe o med
be ween he +5 °C and +20 °C empe a u es o ob ain an app oxima e alue. The elas ic eco e y esul
was 76% o PMB25, which would p edic ably be in class 2 (≥ 75%) a +10 °C. PMB50 ob ained a alue
o 66%, which would esul in class 3 (≥ 50%) a +10 °C.
0
50
100
150
200
050 100 150 200
Fo ce (N)
Leng h (mm)
+5 °C PMB25 +5 °C PMB50
0
2
4
6
8
10
12
14
16
18
050 100 150 200
Fo ce (N)
Leng h (mm)
+20 °C PMB25 +20 °C PMB50
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
72
Fo ce duc ili y
The o ce duc ili y me hod was pe o med a wo es empe a u es, +5 °C and +20 °C o bo h PMB25
and PMB50, as p e iously men ioned. The ecommended es empe a u e, acco ding o EN 13589, is
ypically +5 °C e en hough o he empe a u es can be used. Figu es 52 and 53 show he esul ing
g aphs ob ained o he es ed binde s in he o ce duc ili y me hod.
Figu e 52 – Fo ce duc ili y o PMBs a +5 °C (mean alues)
Figu e 53 – Fo ce duc ili y o PMBs a +20 °C (mean alues)
The o ce duc ili y pe o mance o bo h PMBs a he +20 °C es empe a u e was sa is ac o y, gi en he
ac ha i was possible o de o m all samples up o he 400 mm es ablished by he s anda d. The o ce
equi ed by he PMB50 o elonga e was almos one and a hal imes he o ce equi ed by he PMB25,
0
20
40
60
80
100
120
140
160
0100 200 300 400
Fo ce (N)
Leng h (mm)
+5 °C PMB25 +5 °C PMB50
0
2
4
6
8
10
12
0100 200 300 400
Fo ce (N)
Leng h (mm)
+20 °C PMB25
+20 °C PMB50
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
73
which demons a es he highe ensile s ess limi and duc ili y ene gy e ained by he PMB50 a his
empe a u e.
Conce ning he +5 °C es empe a u e, he one ecommended by he s anda d, bo h PMB did no each
he es ablished 400 mm elonga ion, ha ing a p ema u e b eak nea ha elonga ion. When compa ing
bo h PMBs, i is possible o obse e in Figu e 52 ha hey beha ed e y simila ly, ha ing a high le el o
duc ili y up o 350 mm elonga ion.
By compa ing bo h empe a u es, i is possible o obse e he much highe alue o ene gy equi ed o
s e ch he samples a he +5 °C empe a u e han ha needed a +20 °C, almos ou een imes highe .
In bo h he es ed empe a u es, he shapes o he ob ained cu es a e consis en wi h he inc ease in
s eng h ha should occu in polyme -modi ied bi umens a e he ini ial peak, ha ing an inc ease in
s eng h be ween 200 and 400 mm, e en hough he +20 °C es empe a u e p esen ed a much highe
inc ease in compa ison o he ini ial peak alue. Thus, bo h PMBs ha e excellen duc ili y pe o mance.
Rela ionships be ween o ce duc ili y es esul s and low- empe a u e c acking esis ance o asphal mix
ha e been ound. An inc ease in FD maximum o ce can be an indica ion o highe bi umen s i ness,
which in u n will esul in educed low- empe a u e c acking esis ance, indica ed by highe ailu e
empe a u es (Mollenhaue and Tuša , 2016). F om ha s udy, he high FD o ce encoun e ed by bo h
PMBs can be seen as a p oblem o he low- empe a u e c acking esis ance o he mix u es.
4.3. Analysis o he asphal mix u es and specimens
As acco ding o EN 13108-1 and EN 13108-5, he designa ion o hese mix u es is:
• he mix u e con aining PMB25: SMA 11 PMB 25/55-80;
• he mix u e con aining PMB50: SMA 11 PMB 25/55-80.
Since he designa ion o bo h would no pe mi he di e en ia ion be ween hem, he e minology used
o he PMB om he ini ial s ages will be upheld, and he asphal mix u es will be designa ed as:
• he mix u e con aining PMB25: SMA 11 PMB25;
• he mix u e con aining PMB50: SMA 11 PMB50.
Figu es 54 and 55 p esen he ob ained bulk densi ies o each specimen by he di e en p ocedu es
p o ided by he s anda d, espec i ely o asphal mix u es SMA 11 PMB25 and SMA 11 PMB50.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
74
Figu e 54 – Bulk densi ies o he SMA 11 PMB25 specimens in Mg/m3
Figu e 55 – Bulk densi ies o he SMA 11 PMB50 specimens in Mg/m3
By obse ing bo h g aphs showing he bulk densi y ob ained by he ou di e en me hods p o ided in he
s anda d, i can be seen ha he highes bulk densi y ob ained o he PMB25 mix u e was gene ally
ob ained by me hod B (wi h a neglec able di e ence o p ocedu e A). E en hough me hod C was used
in jus h ee specimens, i is also possible o obse e ha i ob ained usually lowe alues o bulk densi y.
2.31
2.32
2.33
2.34
2.35
2.36
2.37
2.38
2.39
2.40
2.41
2.42
2.43
Bulk densi y (Mg/m3)
A ρbd y B ρbssd C ρbsea D ρb,dim
a e age A a e age B a e age C a e age D
2.31
2.32
2.33
2.34
2.35
2.36
2.37
2.38
2.39
2.40
2.41
2.42
2.43
Bulk densi y (Mg/m3)
A ρbd y B ρbssd C ρbsea D ρb,dim
a e age A a e age B a e age C a e age D
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
81
Figu e 57 –Resul s o TSRST es s
As a compa ison be ween he h ee cooling empe a u es, he s ess ob ained once hey i s eached he
empe a u e o -18 °C was egis e ed and is p esen ed in Table 18.
Table 18 – S ess (N) a -18 °C o he h ee cooling a es
Specimen
Cooling
a e
(°C/h)
S ess (N)
alue mean
alue
s anda d
de ia ion
coe icien o
a ia ion
A2511 -2 1838 1941 103 5%
A2520 2044
A2534 -5 1890 1958 68 3%
A2544 2027
A253
-10
2171
2621 368 14%
A2510 3139
A2517 2773
A2538 2402
The maximum s ess (peak s ess) ob ained o he h ee cooling a es was also egis e ed, along wi h
he empe a u e a which ha alue occu ed. Table 19 p esen s hose esul s.
-5000
-4000
-3000
-2000
-1000
0
-25-20-15-10-505101520
Fo ce (N)
Tempe a u e (°C)
-2 °C/h A2511 -2 °C/h A2520
-5 °C/h A2534 -5 °C/h A2544
-10 °C/h A253 -10 °C/h A2510
-10 °C/h A2517 -10 °C/h A2538

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
82
Table 19 – Peak s ess (N) o he h ee cooling a es
Specimen
Cooling
a e
(°C/h)
Peak s ess (N) Tempe a u es a
which i was ob ained
(°C)
alue mean
alue
s anda d
de ia ion
coe icien
o a ia ion
A2511 -2 2376 2671 295 11% -20.3
A2520 2966 -22.1
A2534 -5 3823 3236 588 18% -22.4
A2544 2648 -21.5
A253
-10
4926
4370 387 9%
-20.7
A2510 4220 -19.7
A2517 3862 -18.5
A2538 4472 -20.6
By obse ing Table 18, i can be e i ied ha he cooling a es o -2 and -5 °C/h p esen simila s esses
a -18 °C, which is somewha isible in Figu e 57. Howe e , once he peak alues a e analysed, a
signi ican di e ence was no iced in Table 19. Thus, bo h cooling a es subjec he pa emen o e y
simila s esses igh up un il e y low empe a u es a e eached. A hese ex emely low empe a u es,
a as e cooling a e causes highe s esses o he mix u e, which in u n can esul in c acking.
Rega ding he cooling a e sugges ed by he s anda d (-10 °C/h), i can be obse ed ha i subjec s he
mix u e o signi ican ly highe s esses han he slowe cooling a es, bo h a -18 °C as well as a highe
es empe a u es. The same beha iou is obse ed o e y low empe a u es, a ound -20 °C, a which
he mix u e p esen s e y high s esses in compa ison wi h jus 2 °C wa me es empe a u e. In
summa y, he -10 °C/h cooling a e mos likely will esul in he mix u e ailu e a highe s ess le els.
By compa ing he h ee cooling a es, he e ec o ha pa ame e on he esul ing alues is e iden . The
as e he cooling a e, he highe he he mal s esses he mix u e will p esen . This aspec is i al in
ega ds o he co ec de ini ion o he cooling a e in he design s age, as o accu a ely e lec he ac ual
condi ions obse ed in he pa emen . Ce ain egions can ha e mo e p opensi y o as e cooling o
di e en easons, and also his apid cooling can occu mo e o en. Thus, he clima e o he egion whe e
he pa emen will be execu ed should be ca e ully s udied in o de o design he asphal mix u e p ope ly.
The alidi y o he da a can be asce ained by obse ing he coe icien s o a ia ion. They all p esen
alues lowe han 20%, which indica es he da a alues a e eliable.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
83
In conclusion, e en hough i was no possible o ob ain he ailu e empe a u e o he mix u e, hose
empe a u es a e lowe han -20 °C, and i is no p edic able ha hose empe a u es will be obse ed in
Po ugal, gi en he local clima e. Thus, he labo a o y es s wi h he es ing machine used will be su icien
o alida e he low- empe a u e pe o mance o his mix u e in Po ugal.
Howe e , in o de o Po uguese companies o be able o compe e in he in e na ional ma ke , pa icula ly
in No he n and Eas e n coun ies, i would be o in e es ha his esea ch wo k can be deepened in
o de o ob ain he ailu e empe a u e and co esponden s ess since lowe ailu e empe a u es om
TSRST indica e ha low- empe a u e c acking should be educed (Nicholls, 2017).
Relaxa ion es
The ini ial inpu alues o he elaxa ion es a e shown in Table 20. The ini ial imposed s ess de i es
om he UTST and should no be g ea e han 75% o he ob ained ensile s eng h β . The elaxa ion
ime is he ime when he s ess is educed o 36.8 ± 0.1% (1/e = 1/2.718 = 0.368) o i s ini ial alue.
Relaxa ion modulus is a main iscoelas ic pa ame e o an asphal mix u e and is used as an essen ial
basis o e alua ing and analysing he pe o mance and p edic ing he long- e m s abili y o a pa emen
(Sun
e al.
, 2018).
Table 20 – Inpu alues o he RT
Pa ame e -20 °C -10 °C +5 °C +20 °C
75% Peak s ess om UTST (N) -6243.1 -7038.2 -4281.9 -651.5
Co esponding inpu s ain (mm) 0.042 0.067 0.130 0.580
These alues e lec he expec ed s ess le el is he pa emen . The di e ence in s ess le els be ween
+20 °C and +5 °C is conside able, and he mix u es a e expec ed o be subjec ed o high s ain le els.
Be ween -10 °C and -20 °C e en hough he s ess om UTST was less on he lowe empe a u e, he
measu ed s ain did no co espond o ally o he expec ed beha iou , ha ing a lowe elaxa ion alue
han ha obse ed a -10 °C empe a u e. The summa y o he esul s ob ained om he RT es s is
shown in Table 21.
All specimens beha ed as p edic ed, as can be obse ed in he e olu ion o s ess e sus ime shown in
Figu es 58 o 60.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
84
Table 21 – Relaxa ion es esul s
Pa ame e -20 °C -10 °C +5 °C +20 °C
RT1 RT2 RT3 RT4 RT5 RT6
Relaxa ion s ess (N) did no
each
did no
each
-2492.0 -1973.6 -1598.3 -749.9
Relaxa ion ime el (s) did no
each
did no
each
2206 45 49 33
Relaxa ion ime el
(hh:mm:ss)
did no
each
did no
each
00:36:46 00:00:45 00:00:49 00:00:33
Tes s opping ime (s) 172991 172991 - - - -
Tes s opping ime
(hh:mm:ss) 48:03:11 48:03:11 - - - -
S ess a end o es (N) -2778.7 -2420.5 - - - -
Figu e 58 – E olu ion o s ess (N) wi h ime (s) o bo h specimens es ed a -20 °C
Figu e 59 – E olu ion o s ess (N) wi h ime (s) o he specimen es ed a -10 °C
-7000
-6000
-5000
-4000
-3000
-2000
-1000
0
0 2000 4000 6000 8000 10000 12000 14000 16000
S ess (N)
Time (s)
RT1 -20 RT2 -20
-7000
-6000
-5000
-4000
-3000
-2000
-1000
0
0 200 400 600 800 1000 1200 1400 1600 1800 2000
S ess (N)
Time (s)
RT3 -10
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
85
Figu e 60 – E olu ion o s ess (N) wi h ime (s) o he specimen es ed a +5 °C and +20 °C
I can be obse ed ha o highe empe a u es, he asphal mix u e eached he elaxa ion ime e y
quickly, unde a minu e. This esul is consis en wi h he obse ed expe ience in he li e a u e ha he
heological p ope ies o he asphal mix u es a e a ec ed by empe a u e, ehicle load and ehicle speed.
Once pa emen s a e subjec ed o s ess, i is g adually dissipa ed o e ime, and elaxa ion occu s. When
he empe a u e is high, he s ess accumula ed in he pa emen will dissipa e quickly because o a
s onge elaxa ion abili y, which is e i ied in his s udy.
Fo he -10 °C empe a u e, he elaxa ion ime was eached a e app oxima ely 36 minu es. Howe e ,
o he -20 °C empe a u e, bo h specimens we e no able o each he elaxa ion ime in he 48 hou s
p oposed by he s anda d. This es should be concluded when s ess le el alls below 36% o i s ini ial
alue (2125.9 o RT1; 1809.4 o RT2). The inal s ess le el o RT1 was 2778.7 N, while o RT2 was
2420.5 N, and bo h a e nea he p e-es ablished alue o 36%. Ne e heless, by obse ing hei cu es in
he s ess e sus ime g aph in Figu e 58, i is p edic able ha hey would ake a long ime o each he
elaxa ion ime since bo h cu es p esen a s eady bu slow beha iou .
Acco ding o Sun
e al.
(2018), when he empe a u e is low, he s ess in he pa emen dissipa es slowly
because o poo elaxa ion abili y, which is con i med by his s udy. When his occu s, c acks in he
pa emen may appea , a p oduc o he inal s ess being mo e signi ican han he ul ima e s eng h o
he mix u e.
O e all, his mix u e p esen s a ema kable beha iou a low and medium empe a u es when i ela es
o elaxa ion. Some slow elaxa ion issues o he mix u e may only occu a e y low empe a u es (-20 °C)
i he pa emen is subjec ed o hese empe a u es o an ex ended pe iod.
-7000
-6000
-5000
-4000
-3000
-2000
-1000
0
20 25 30 35 40 45
S ess (N)
Time (s)
RT4 +5 RT5 +5
RT6 +20
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
86
Tensile c eep es
A c eep es (some imes e e ed o as a s ess- elaxa ion es ) is used o de e mine he amoun o
de o ma ion a ma e ial expe iences o e ime while unde a con inuous ensile load a a cons an
empe a u e. The esul s om he ensile c eep es s a di e en empe a u es a e shown in Figu e 61.
Figu e 61 – Resul s o TCT es s
As can be obse ed om he g aph in Figu e 61, bo h he limi empe a u es o -20 °C and +20 °C
demons a e a simila beha iou in his es , wi h almos co esponding alues o s ain e olu ion wi h
ime. They bo h eco e ed almos he whole de o ma ion achie ed p e iously. I is essen ial o unde s and
ha his is only concei able because he imposed s ess le el, de ined in he s anda d, is much lowe a
highe empe a u es.
The empe a u e o -10 °C p esen ed a highe de o ma ion alue han ha obse ed in he p e ious wo
empe a u es and eco e ed pa o i s maximum de o ma ion. I s peak o de o ma ion was ob ained a
0.208 mm and eco e ed 0.064 mm, which p esen s an app oxima e eco e y o 30% o he ini ial
de o ma ion. The s ess le el imposed in he s anda d a his empe a u e o igina ed a wo se beha iou
o he mix u e a his empe a u e.
Ne e heless, he wo s pe o mance was obse ed a he empe a u e o +5 °C, wi h a conside able
de o ma ion unde he s anda d imposed s ess le el, and only eco e ing a iny p opo ion o ha
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0 3000 6000 9000 12000 15000 18000 21000 24000 27000 30000 33000 36000
S ain (mm)
Time (s)
+20 °C A2538
+5 °C A2516
-10 °C A2530
-20 °C A2542

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
87
de o ma ion. The mix u e de o med 0.939 mm and eco e ed 0.112 mm, which esul s in a eco e y o
only 12% o he ini ial de o ma ion.
These esul s indica e ha a high empe a u es, as well as e y low empe a u es, his asphal mix u e
mos likely will no p esen de o ma ion issues. The same canno be said o he in e media e
empe a u es o +5 °C and -10 °C, pa icula ly a +5 °C, conside ing he s ess alues imposed in he
s anda d. In his empe a u e ange, he mix u e only eco e ed 12% o he ini ial de o ma ion, which can
indica e ha de o ma ion can occu du ing he li e ime o he pa emen , depending on he condi ions i
would be subjec ed. This es simula es he e ec s caused in he pa emen when a load is applied by
ehicles o he mal s esses and hen is emo ed when hose condi ions change. I he asphal mix u e
is no able o eco e om he load p omp ly, ha will esul in de o ma ion damage o he pa emen as
mo e loads a e applied. These e ec s o ansi o y loading and unloading o asphal mix u es cause
de o ma ions which can, o e ime, esul in u ing o c acking o he pa emen (Hischke, 2019).
Fu he analysis in o de o i a c eep model o he obse ed cha ac e is ics would be o in e es . SABITA
(2015) indica es ha an appa en co ela ion exis s be ween elas ic eco e y and de o ma ion esis ance.
Those au ho s men ioned ha an inc ease in elas ic eco e y p o ides be e pe o mance o
de o ma ion, as well as he inc ease o he cohesi e s eng h.
A model desc ibing he iscoelas ic p ope ies de i ed om he esul s in his es would also be o in e es .
Many models ha e been s udied o desc ibe hese p ope ies, such as he Bu ge s model, Hue –Sayegh
model o desc ibe he iscoelas ic componen , Pe zyna- ype model o desc ibe he iscoplas ic
componen , among many o he s. A compa ison be ween hose di e en models can u he augmen he
knowledge in his ield, in o de o show hei di e ences and de e mine hei accu acy. Fo example,
Ho nych
e al.
(2012) obse ed ha he iscoelas ic s ains calcula ed wi h he model we e mo e ex ensi e
han he expe imen al iscoelas ic s ains ob ained du ing he unloading phase o he c eep es . Pszczoła
and Judycki (2009) also obse ed ha he elas ic modulus and iscosi y coe icien inc eased wi h he
dec ease in empe a u e, which indica es an inc eased s i ness o he s udied mix u es.
Uniaxial cyclic ensile s ess es
Table 22 below p esen s he inpu alues o he base s ess Fc y(T), he s ess caused by he a ic load
ΔF, as well as he peak s ess F o . These alues a e in ended o simula e he dynamic loading condi ion
caused by a ic, which is gi en by he a ic load ΔF in combina ion wi h cons an s ess, gi en by he
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
88
base s ess Fc y(T), which symbolizes he expec ed c yogenic ( he mal) s ess in he pa emen . This
c yogenic componen is de i ed om he TSRST es , in which he s ess a he UCTST es empe a u e
is ob ained om he cu e s ess s empe a u e. The sum o bo h hese s esses esul s in he maximum
s ess he specimen is subjec ed o, he peak s ess F o . These alues in end o e lec he
ension/comp ession load pa e ns obse ed a he bo om o he asphal pa emen laye whe e cyclic
loading is applied in e ms o epe i i e load cycles comp ising ensile and comp essi e loading
(Mollenhaue and Wis uba, 2012).
Table 22 – Inpu alues o UCTST
Pa ame e -20 °C -10 °C +5 °C +20 °C
Base s ess Fc y(T) (N) 3910 473 37 4
T a ic load
Δ
F (N) 2560 2560 2560 2560
Peak s ess F o (N) 6470 3033 2597 2564
Ano he conside a ion is he es equency. As p e iously s a ed, a alue o 10 Hz was selec ed in his
wo k. The es equency is mean o simula e he ac ual loading a e he pa emen is subjec ed o due
o he a ious a ic speeds. Saal and Pell (1960) analysed he in luence he es equency can ha e in
cyclic con olled es s, and hey concluded i could be conside able since he a igue li e o an asphal
mix u e a a equency o 13 Hz was ound o be signi ican ly lowe han o a equency o 50 Hz. Thus,
i may be o in e es o con inue he esea ch ca ied ou in his wo k wi h di e en es equencies in he
u u e, a e adjus ing he es ing de ice o pe o m addi ional es s.
The inpu alues used in he es e lec he s esses caused in he pa emen due o he dec ease in
empe a u e. As can be obse ed, he di e ence in c yogenic s ess be ween +20 °C and +5 °C is
negligible, bu i is inc eased when he empe a u e dec eases o -10 °C. Be ween -10 °C and -20 °C, a
jump in c yogenic s ess can be obse ed, which may indica e ha he pa emen wi h his mix u e will
no su e signi ican he mal s esses due o low empe a u e un il i eaches e y low empe a u es (nea
-20 °C). The summa y o he esul s ob ained om he UCTST es s is shown in Table 23.
A c i e ion o a maximum o 3.0 million cycles was es ablished o he specimen o each ailu e. This
c i e ion was based on a es ic ion o ime o he labo a o y es s o be pe o med. I esul s in con inuous
es ing o abou h ee and a hal days. This issue, along wi h o he cons ain s, limi ed he numbe o
specimens ha could be es ed in his wo k.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
89
Table 23 – Resul s o he UCTST
Tempe a u e (°C) -20 °C -10 °C -10 °C +5 °C +5 °C +20 °C
Specimen UC1 UC1 UC2 UC1 UC2 UC1
Type o ailu e did no each
ailu e
did no each
ailu e
did no each
ailu e ac u e ac u e ac u e
Numbe o load
applica ions N ailu e
1.5 million
cycles
3.0 million
cycles
2.4 million
cycles
10 000
cycles
15 000
cycles
451
cycles
Fa igue beha iou can be cha ac e ised by ela ing he s ain o a mix u e o he numbe o load
applica ions o ailu e (Hassan
e al.
, 2014).
The specimens beha ed acco dingly o he expec ed es p inciple. An example o hei beha iou is shown
in Figu e 62. The s ain shows he de o ma ion o he specimen, and he s ess shows he applied load.
Figu e 62 – Beha iou o es specimen a -10 °C du ing he ini ial cycles o UCTST
The h ee specimens es ed a highe es empe a u es (+20 °C and +5 °C) eached ailu e. The es a
+20 °C ook only 451 cycles o each ailu e, which co esponds o an elonga ion o 3.5 mm be o e i
b eaks. Bo h specimens a +5 °C empe a u e eached ailu e, bu due o a p oblem in he eco ding
equipmen , i was only able o eco d 10 000 cycles. The beha iou o his specimen showed an almos
linea p og essi e cu e ega ding he s ains eco ded by he h ee LVDT. The o he specimen eached
ailu e p esumably a 15 000 cycles, al hough he specimen showed an unusual beha iou conce ning
0 60000 120000 180000 240000 300000
-34.05
-34.00
-33.95
-33.90
-33.85
-33.80
-33.75
-33.70
-3500
-3000
-2500
-2000
-1500
-1000
-500
0
0 0.2 0.4 0.6 0.8 1
Time (s) [ s. s ain]
S ain (mm)
S ess (N)
Time (s) [ s. s ess]
s ess s ain
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
90
he s ains eco ded (Figu e 63). I can be seen ha he h ee LVDTs eached he maximum ange o
de o ma ion, which is app oxima ely 5 mm.
Figu e 63 – Unusual beha iou o specimen 2 a +5 °C in UCTST
The es o he specimens we e es ed a -10 °C and -20 °C empe a u es wi hou eaching ailu e.
Specimen 1 o -10 °C empe a u e eached he p e-es ablished 3.0 million cycles c i e ion, ob aining an
elonga ion o 0.259 mm a he end o he es , while specimen 2 eached 2.4 million cycles. Since
specimen 1 was al eady es ed, i was decided o end he es . A 2.4 million cycles, specimen 2 eached
an elonga ion o 0.275 mm, sligh ly highe han ha o specimen 1. Bo h hese specimens p esen ed a
linea p og essi e s ain beha iou .
Finally, he specimen es ed a -20 °C was es ed un il 1.5 million cycles. A his poin , i p esen ed an
elonga ion o only 0.054 mm. I s s ain beha iou was slow and p og essed linea ly. Based on he
p e ious es s a -10 °C and hei espec i e elonga ions, i was decided o s op he es a hal o he
p e-es ablished c i e ion o he numbe o cycles since he p og ess o s ain was e y slow and
p esumably, he specimen would no each ailu e a 3.0 million cycles.
Mollenhaue and Wis uba (2012) also e lec on he appea ance o he su aces o he b oken specimens
hal es. These depend on he mix u e p ope ies and es condi ions, pa icula ly on es empe a u e. The
ac u e may be obse ed o un h ough he binde mas ic, which can indica e ailu e by cohesion,
h ough he binde -agg ega e in e ace, which can indica e ailu e by adhesion, o di ec ly h ough he
agg ega e, which can indica e he o e s epping o he s eng h p o ided by he agg ega e. The la e is
mainly obse ed a low es empe a u es. Since he specimens a low empe a u es did no each ailu e,
-3
-2
-1
0
1
2
3
-60
-50
-40
-30
-20
-10
0
0 2000 4000 6000 8000 10000 12000 14000 16000
S ain (mm) [LVDTs]
S ain (mm) [s oke_ax]
Numbe o cycles
s oke_ax LVDT_10mm LVDT_VIGA
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
97
REFERENCES
Ai ey, G.D. (2001). Viscosi y-Tempe a u e E ec s o Polyme Modi ica ion as Depic ed by Heukelom's
Bi umen Tes Da a Cha ,
In e na ional Jou nal o Pa emen Enginee ing
, Vol. 2 (4).
Ai ey, G.D. (2002). Rheological e alua ion o e hylene inyl ace a e polyme modi ied bi umens,
Cons uc ion and Building Ma e ials
, Vol. 16 (8), pp. 473-487.
Ai ey, G.D. (2003). Rheological p ope ies o s y ene bu adiene s y ene polyme modi ied oad bi umens,
Fuel
, Vol. 82 (14), pp. 1709-1719.
Ala aş, T., Yilmaz, M. (2017). Low empe a u e p ope ies o ho mix asphal s p epa ed wi h di e en
polyme modi ied binde s,
Jou nal o he C oa ian Associa ion o Ci il Enginee s
, Vol. 69, pp. 93-
104.
Almusawi, A., Sengoz, B., Topal, A., One, J. (2019). Compa ison be ween Ze o Shea Viscosi y and S eady
Shea Flow Me hods o de e mine mixing and compac ion empe a u es o PMB,
Eu asian Jou nal
o Ci il Enginee ing and A chi ec u e
, Vol. 3 (2), pp. 1-8.
Asphal Ins i u e (2019).
Indi idual Asphal Binde Tes s
, Lexing on, Asphal Ins i u e;
h p://www.asphal ins i u e.o g/labo a o y/ es ing-se ices/indi idual-asphal -binde - es s/;
Acedido em 4/7/2019.
Asphal Ins i u e (2020).
De e mining Lab Mixing and Compac ion Tempe a u es o Binde s
, Lexing on,
Asphal Ins i u e; h p://www.asphal ins i u e.o g/enginee ing/de e mining-lab-mixing-
compac ion- empe a u es-binde s/; Acedido em 13/1/2020.
Becke , Y., Méndez, Ma y o P., e Rod íguez, Yajai a (2001). Polyme modi ied asphal ,
Vision Tecnologica
,
Vol. 9 (1).
Behnood, A., Ame i, M. (2012). Expe imen al in es iga ion o s one ma ix asphal mix u es con aining
s eel slag,
Scien ia I anica
, Vol. 19 (5), pp. 1214-1219.
Be nucci, L., Mo a, L., Ce a i, J., Soa es, J. (2010).
Pa imen ação as ál ica
, Rio de Janei o.
Blazejowski, K. (2011).
S one Ma ix Asphal heo y and p ac ice
, CRC P ess Taylo & F ancis G oup.
Bou e in, B., Pie asan a, Y., Robin, J.J. (1989). Bi umen-polyme blends o coa ings applied o oads
and public cons uc ions,
P og ess in O ganic Coa ings
, Vol. 17 (3), pp. 221-249.
B anco, F., Pe ei a, P., Picado San os, L. (2011).
Pa imen os Rodo iá ios
, Edições Almedina.
B andão, M.F.C.M. (2015).
Es udo de be umes modi icados ecupe ados de mis u as p oduzidas pelo
mé odo húmido e pelo mé odo seco
.
B own, E., Mallick, R., Haddock, J., Bukowski, J. (1997). Pe o mance o s one ma ix asphal (SMA)
mix u es in he Uni ed S a es,
Jou nal o he Associa ion o Asphal Pa ing Technologis s
.
Bu gue e, L.M.F. (2013).
Con ibuição pa a o es udo do compo amen o de mis u as be uminosas
inco po ando nanoma e iais
, Ins i u o Supe io Técnico.
CEN (2012).
EN 12697-46 Bi uminous mix u es - Tes me hods o ho mix asphal - Pa 46: Low
empe a u e c acking and p ope ies by uniaxial ension es s
, Eu opean Commi ee o
S anda diza ion, B ussels.
Das, P., Tasdemi , Y., Bi gisson, B. (2012). Low empe a u e c acking pe o mance o WMA wi h he use
o he Supe pa e indi ec ensile es ,
Cons uc ion and Building Ma e ials
, pp. 643-649.

In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
98
Domínguez, J.C. (2018). Rheology and cu ing p ocess o he mose s,
The mose s: S uc u e, P ope ies,
and Applica ions
, p. 115-146, Else ie .
EAPA (2018).
Hea y du y su aces The A gumen s o SMA
, Eu opean Asphal Pa emen Associa ion,
B ussels, Belgium.
EAPA (2019).
EAPA. Eu opean Asphal Pa emen Associa ion
, B ussels, Eu opean Asphal Pa emen
Associa ion; h ps://eapa.o g/; Acedido em 9/7/2019.
Ebewele, R.O. (2000).
Polyme Science and Technology
, CRC P ess.
EC (2019).
En i onmen
, Eu opean Commission;
h ps://ec.eu opa.eu/en i onmen /na u e/na u a2000/biogeog_ egions/con inen al/index_en.
h m; Acedido em 14/10/2019.
El-Badawy, S., Abd El-Hakim, R. (2018).
Recen De elopmen s in Pa emen Design, Modeling and
Pe o mance
, P oceedings o he 2nd GeoMEas In e na ional Cong ess and Exhibi ion on
Sus ainable Ci il In as uc u es, Egyp .
Encyclopaedia B i annica (2019).
Polyme
; h ps://www.b i annica.com/science/polyme ; Acedido em
12/12/2019.
Fe nandes, S., Pe ei a, S., Sil a, H., Oli ei a, J., Palha, C. (2016).
A aliação de mé odos de ca ac e ização
de be umes modi icados
, 1º Cong esso de Ensaios e Expe imen ação em Engenha ia Ci il,
Relac e, IST, Lisboa.
Gawel, I., S epkowski, R., Czechowski, F. (2006). Molecula In e ac ions be ween Rubbe and Asphal ,
Indus ial & Enginee ing Chemis y Resea ch
, Vol. 45 (9), pp. 3044-3049.
Hassan, N., Ai ey, G., Pu a Jaya, R., Mash os, N., A. Aziz, M.M. (2014). A Re iew o C umb Rubbe
Modi ica ion in D y Mixed Rubbe ised Asphal Mix u es,
Ju nal Teknologi
, Vol. 70.
Hassan, N., Ai ey, G., Yuso , N., Hainin, M., Pu ajaya, R., Abdullah, M., Aziz, M. (2015). Mic os uc u al
cha ac e isa ion o d y mixed ubbe ised asphal mix u es,
Cons uc ion and Building Ma e ials
,
Vol. 82, pp. 173-183.
Hischke, G. (2019).
Unde s anding C eep in Asphal Conc e e
, Illinois Asphal Pa ing Associa ion (IAPA).
Ho nych, P., Blanc, J., Gabe , T., a, P., Piau, J., Di Benede o, H. (2012). C eep es s on bi uminous
mix u es and modelling,
Road Ma e ials and Pa emen Design
.
Isacsson, U., Zeng, H. (1997). Rela ionships be ween bi umen chemis y and low empe a u e beha iou
o asphal ,
Cons uc ion and Building Ma e ials
, Vol. 11 (2), pp. 83-91.
Judycki, J. (2014). In luence o low- empe a u e physical ha dening on s i ness and ensile s eng h o
asphal conc e e and s one mas ic asphal ,
Cons uc ion and Building Ma e ials
, Vol. 61, pp. 191-
199.
Kim, K.W., Hussein, M.E. (1997). Va ia ion o ac u e oughness o asphal conc e e unde low
empe a u es,
Cons uc ion and Building Ma e ials
, Vol. 11 (7-8), pp. 403-411.
Lesueu , D. (2009). The Colloidal S uc u e o Bi umen: Consequences on he Rheology and on he
Mechanisms o Bi umen Modi ica ion,
Ad ances in Colloid and In e ace Science
, Vol. 145 (1-2),
pp. 42-82.
Mandal, T., Sylla, R., Bahia, H., Ba mand, S. (2015). E ec o c oss-linking agen s on he heological
p ope ies o polyme -modi ied bi umen,
Road Ma e ials and Pa emen Design
.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
99
Mi anda, H.M.B., Ba is a, F.A., An unes, M.d.L., Ne es, J. (2019). A new SMA mix design app oach o
op imisa ion o s one-on-s one e ec ,
Road Ma e ials and Pa emen Design
, Vol. 20.
Mollenhaue , K., Tuša , M. (2016).
FunDBi S : unc ional du abili y- ela ed bi umen speci ica ion.
Deli e able D.2c, co ela ions be ween bi umen and asphal p ope ies : low empe a u e c acking
,
Con é ence Eu opéenne des Di ec eu s des Rou es = Con e ence o Eu opean Di ec o s o Roads
(CEDR), p. 18, B uxelles.
Mollenhaue , K., Wis uba, M. (2012). E alua ion o ho -mix asphal suscep ibili y o empe a u e-induced
op-down a igue c acking by means o Uniaxial Cyclic Tensile S ess Tes ,
Road Ma e ials and
Pa emen Design
, Vol. 13 (1), pp. 171-190.
Nicholls, C. (2017).
Asphal Mix u e Speci ica ion and Tes ing
, CRC P ess.
Paliukai , M., Vai kusa, A., Zo kab, A. (2014).
E alua ion o bi umen ac ional composi ion depending on
he c ude oil ype and p oduc ion echnology.
, 9 h In e na ional Con e ence “En i onmen al
Enginee ing” Selec ed Pape s, p. 22–23, Vilnius, Li huania.
Panga o a, D., Nikolo , A. (2016).
S udy o he low empe a u e cha ac e is ics o binde s and he asphal
mix u es p oduced wi h hem
, 6 h Eu asphal & Eu obi ume Cong ess, P ague.
Pa emen In e ac i e (2019).
Pa emen In e ac i e: F ee online knowledge o he pa ing indus y
,
Pa emen In e ac i e,; h ps://pa emen in e ac i e.o g/; Acedido em 13/6/2019.
Polacco, G., Kříž, P., Filippi, S., S as na, J., Biondi, D., Zanzo o, L. (2008). Rheological p ope ies o
asphal /SBS/clay blends,
Eu opean Polyme Jou nal
, Vol. 44 (11), pp. 3512-3521.
Po o, M., Capu o, P., Loise, V., Eskanda se a , S., Tel aye , B., Rossi, C.O. (2019). Bi umen and Bi umen
Modi ica ion: A Re iew on La es Ad ances,
Applied Sciences
.
Pszczola, M., Jaczewski, M., Szydlowski, C. (2019a). Assessmen o The mal S esses in Asphal Mix u es
a Low Tempe a u es Using he Tensile C eep Tes and he Bending Beam C eep Tes ,
Applied
Sciences
, Vol. 9 (5).
Pszczoła, M., Judycki, J. (2009).
Tes ing o low empe a u e beha iou o asphal mix u es in bending
c eep es
, 7 h In e na ional RILEM Symposium ATCBM09 on Ad anced Tes ing and
Cha ac e iza ion o Bi uminous Ma e ials, Rhodes, G eece.
Pszczola, M., Judycki, J., Ryś, D. (2016). E alua ion o Pa emen Tempe a u es in Poland Du ing Win e
Condi ions,
T anspo a ion Resea ch P ocedia
, Vol. 14, pp. 738-747.
Pszczola, M., Szydlowski, C. (2018). In luence o Bi umen Type and Asphal Mix u e Composi ion on Low-
Tempe a u e S eng h P ope ies Acco ding o Va ious Tes Me hods,
Ma e ials
.
Pszczola, M., Szydlowski, C., Jaczewski, M. (2019b). In luence o cooling a e and addi i es on low-
empe a u e p ope ies o asphal mix u es in he TSRST,
Cons uc ion and Building Ma e ials
, Vol.
204, pp. 399-409.
Qui k, R.P., Kinning, D.J., Fe e s, L.J. (1989). 1 - Block Copolyme s,
Comp ehensi e Polyme Science
and Supplemen s
, Vol. 7, pp. 1-26.
Read, J., Wi heoak, D. (2003).
The Shell Bi umen Handbook
, Thomas Tel o d Publishing, London, UK.
Remišo á, E., Holý, M. (2017).
Changes o P ope ies o Bi umen Binde s by Addi i es Applica ion
, IOP
Con e ence Se ies: Ma e ials Science and Enginee ing, IOP Publishing L d.
Saal, R., Pell, P. (1960).
Fa igue o bi uminous mixes
, Con e ence on Flow, Fa igue and Failu e o he
B i ish Socie y o Rheology.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
100
SABITA (2015).
Technical Guideline : The Use O Modi ied Bi uminous Binde In Road Cons uc ion
,
Sou he n A ican Bi umen Associa ion (Sabi a).
Saboo, N., Kuma , P. (2016). Op imum Blending Requi emen s o EVA Modi ied Binde ,
T anspo a ion
Resea ch P ocedia
, Vol. 17, pp. 98-106.
Schei s, J. (2003).
Mode n S y enic Polyme s: Polys y enes and S y enic Copolyme s
, John Wiley & Sons.
Senço, W. (2001).
Manual de Técnicas de Pa imen ação
, Pini L da.
Sengoz, B., Isikyaka , G. (2008). E alua ion o he p ope ies and mic os uc u e o SBS and EVA polyme
modi ied bi umen,
Cons uc ion and Building Ma e ials
, Vol. 22 (9), pp. 1897-1905.
Sheka , P.C., H., R.B., Vishwas, J.S. (2018). Expe imen al in es iga ion o S one Mas ic Asphal by a ying
mix design.,
In e na ional Resea ch Jou nal o Enginee ing and Technology (IRJET)
, Vol. 5 (5), pp.
300–305.
Shenoy, A. (2001). De e mina ion o he Tempe a u e o Mixing Agg ega es wi h Polyme -Modi ied
Asphal s,
In e na ional Jou nal o Pa emen Enginee ing
, Vol. 2 (1), pp. 33-47.
SHI (2019).
Science Ma e s: The Case o Plas ics
, Philadelphia, Science His o y Ins i u e;
h ps://www.sciencehis o y.o g/ he-his o y-and- u u e-o -plas ics; Acedido em 11/11/2019.
Shinoha a, K.J., Momm, L., Leand o, G.C., Ba a, B.S., Pé ez, Y.A.G. (2011). A aliação do e ei o da
adição do políme o EVA nas p op iedades do ligan e as ál ico 50/70,
Uni e sidade Fede al de
San a Ca a ina
.
Sil a, H.M.R.D., Oli ei a, J., Fe ei a, C.I.G., Pe al a, E.J.F. (2009).
E alua ion o he heological beha iou
o Wa m Mix Asphal (WMA) modi ied binde s
, 7 h In e na ional RILEM, Taylo & F ancis, p. 661-
673, Rhodes.
Špaček, P., Heg , Z., Beneš, J. (2017). P ac ical expe iences wi h new ypes o highly modi ied asphal
binde s,
IOP Con e ence Se ies: Ma e ials Science and Enginee ing
, Vol. 236.
S imilli, A., Vi gili, A., Canes a i, F., Bahia, H.U. (2017). Es ima ion o low- empe a u e pe o mance o
ecycled asphal mix u es h ough elaxa ion modulus analysis,
Cold Regions Science and
Technology
, Vol. 133, pp. 36-45.
S ock, A.F., A and, W. (1993).
Low empe a u e c acking in polyme modi ied binde s
, Asphal Pa ing
Technology 1993, Aus in, Texas.
Sun, Y., Gu, Z., Wang, J., Fang, C., Yuan, X. (2018). S udy on Relaxa ion Damage P ope ies o High
Viscosi y Asphal Sand unde Uniaxial Comp ession,
Ad ances in Ci il Enginee ing
(Pa emen
Analysis and Design by Mul iphysics).
The Cons uc o (2020).
Types o Pa emen – Flexible Pa emen s and Rigid Pa emen s
, The Cons uc o .
Ci il Enginee ing Home; h ps:// hecons uc o .o g/ anspo a ion/ ypes-o -pa emen - lexible-and-
igid-pa emen /9570/; Acedido em 12/1/2020.
To es, H. (2014).
U ilização de be umes modi icados na egene ação de mis u as com ele adas
pe cen agens de eciclagem
.
To h, C., Pe ho, L., Geige , A., Soós, Z. (2016).
Pe o mance assessmen o ho mix asphal wi h
chemically s abilized ubbe bi umen
, JO - P oceedings o 6 h Eu asphal & Eu obi ume Cong ess
2016.
Vai kus, A., Vo objo as, V., Žiliū ė, L. (2009).
The esea ch on he use o wa m mix asphal o asphal
Pa emen s uc u es
, XXVII In e na ional Bal ic Road Con e ence, Riga, La ia.
In luence o he modi ica ion o asphal mix u es on hei beha iou a low empe a u es
101
Van Ams e dam, E. (2000).
Cons uc ion ma e ials o ci il enginee ing
, Ju a and Company L d.
Vonk, W., Schol en, E.J., Ko ens a, J. (2010).
No el Class o SBS Polyme s o Enhanced E ec i eness
in Bi umen Modi ica ion
, Aus alian Asphal Pa ing Associa ion Thi een h In e na ional Flexible
Pa emen s Con e ence, Queensland, Aus alia.
Walke , D. (2019).
The bene i s o modi ied asphal s
, Asphal : The Magazine o he Asphal Ins i u e;
h p://asphal magazine.com/ he-bene i s-o -modi ied-asphal s/; Acedido em 8/9/2019.
Wang, T.-h., Su, L.-j., Zhai, J.-y. (2014). A case s udy on diu nal and seasonal a ia ion in pa emen
empe a u e,
In e na ional Jou nal o Pa emen Enginee ing
, Vol. 15 (5).
Wo ldA las (2019).
Eu ope Wea he
; h ps://www.wo lda las.com/webimage/coun ys/euwea he .h m;
Acedido em 11/10/2019.
Zaniewski, J.P., Pumph ey, M.E. (2004).
E alua ion o Pe o mance G aded Asphal Binde Equipmen
And Tes ing P o ocol
, Asphal Technology P og am.
Zhang, B., Chen, H., Zhang, H., Kuang, D., Wu, J., Zhang, X. (2019). A S udy on Physical and Rheological
P ope ies o Rubbe ized Bi umen Modi ied by Di e en Me hods,
Ma e ials
.