Inno a i e Building Ma e ials Con aining
Pos -Consume Plas ics: A Rewa ding Example
o Ci cula Economy in Cons uc ion
Ma iaen ica F igione1(B)and José Luís Ba oso de Aguia 2
1Depa men o Inno a ion Enginee ing, Uni e si y o Salen o, Lecce, I aly
[email p o ec ed]
2Depa men o Ci il Enginee ing, Uni e si y o Minho, B aga, Po ugal
[email p o ec ed]
Abs ac . Ci cula Economy, which i is among he p io i ies o he Eu opean
Commission, is de ined as an economy in which he alue o p oduc s, ma e ials
and esou ces is main ained o as long as possible and he p oduc ion o was e is
educed o minimum. Keeping in mind he impac on he en i onmen caused on
he one hand by pos -consume plas ic was e and on he o he hand by p oduc ion
p ocesses o conc e e, i is possible o ind a solu ion able, a leas pa ly, o mi iga e
hese wo issues. Following he p inciples o he ci cula economy, in ac , i is
possible o euse pos -consume plas ic was e as ine agg ega es in conc e e: in
his way, pos -consume plas ic om was e becomes a esou ce; a he same ime,
he use o o he na u al esou ces is limi ed, such as he mine als adi ionally
used as agg ega es in conc e e. Howe e , his i uous solu ion s ill p esen s some
p oblems o s udy and sol e: his wo k aims o illus a e some o hese issues, and
p o ides indica ions on he aspec s o be analyzed and sol ed.
Keywo ds: Ci cula economy ·Conc e e ·Pos -consume plas ics ·Recycling ·
Sus ainable building ma e ials
1 In oduc ion: Ci cula Economy P inciples
Ci cula Economy (CE) is de ined as an economy in which he alue o p oduc s, ma e-
ials and esou ces is main ained o as long as possible; his can be achie ed by eusing,
epai ing, econdi ioning and ecycling exis ing ma e ials, ex ending hei li e cycle and
minimizing he p oduc ion o was e. I is among he p io i ies o he Eu opean Commis-
sion o suppo sus ainable g ow h and job c ea ion [1]. The demand o aw ma e ials
is, in ac , con inuously inc easing while he na u al esou ces a e going o be deple ed,
esou ces ha a e essen ial o an economy s uggling wi h a cons an ly g owing wo ld
popula ion. Fu he mo e, he p ocu emen o aw ma e ials (no a ailable in e nally)
leads o dependence on o he Coun ies, and we ha e ecen ly lea ned how much his
can damage a Coun y’s economy. Ac ions in his di ec ion gi e a s ong boos o p oduc
and p ocess inno a ion, wi h an inc ease in compe i i eness and economic g ow h.
© The Au ho (s) 2025
L. Cza necki e al. (Eds.): ICPIC 2023, 61, pp. 87–97, 2025.
h ps://doi.o g/10.1007/978-3-031-72955-3_7
88 M. F igione and J. L. B. de Aguia
The adop ion o he p inciples o he CE is also an e ec i e esponse o cu en
en i onmen al issues, as he p ocesses o ex ac ion and use o aw ma e ials p oduce a
g ea impac on he en i onmen and inc ease ene gy consump ion and CO2emissions.
Fu he mo e, acco ding o CE was e can become a p o i able esou ce, no longe a
p oblem o be managed: i is possible o gene a e alue om was e. The economic model
long pu sued hanks o a la ge a ailabili y o ma e ials and ene gy, which in ol ed an
eno mous exploi a ion o esou ces wi h massi e p oduc ion o was e, mus be eplaced
by a mo e sus ainable model in which was e mus be eused/ ecycled, hus e u ning
economic alue o an asse , a he same ime educing i s disposal cos s. To his ega d,
Ci cula Economy s a egies can o e new oppo uni ies also o plas ic was e which
can be ecycled ins ead o being dumped in o he en i onmen causing he well-known
se ious en i onmen al p oblems. CE ep esen s, he e o e, a model o a closed sys em
which p omo es he euse o plas ic p oduc s in a logic o conse a ion o esou ces,
gene a es alue om was e p oducing new eco-sus ainable p oduc s, and a oids sending
a ma e ial ha is s ill eco e able o land ill.
2 Pos -Consume Plas ics: Disposal and Recycle
In 2020, he wo ld plas ic p oduc ion eached 367 M ons while he Eu opean plas ic
p oduc ion was 55 M ons [2]. A e a signi ican decline in he i s hal o 2020 due
o he pandemic, he p oduc ion o plas ics has eco e ed since he second hal o he
same yea . The eco e y was condi ioned by he impac o he pandemic which inc eased
he demand o plas ics by majo indus ies, o he p oduc ion o disposable pe sonal
p o ec i e equipmen and o cope wi h he massi e demand o packaging o shipping
o p oduc s du ing he global lockdown. A he same ime, many companies ha e aced
supply chain dis up ions, aw ma e ials sho ages and ising ene gy p ices.
In2020, hedemando plas icma e ialsinEu ope eached49.1M ons, hepackaging
and cons uc ion sec o s ep esen ing by a he la ges end use s o such ma e ials.
The polyme s mainly used in hese indus ies a e polyole ins (i.e. polye hylene, PE,
and polyp opylene, PP), polys y ene (PS), poly inyl chlo ide (PVC) and polye hylene
e eph hala e (PET). A he end o hei use ul li e (p obably e y sho in packaging
applica ions), hese polyme s a e no comple ely biodeg adable, hei biodeg ada ion
being ex emely slow and occu ing o a limi ed ex en only in app op ia e en i onmen al
condi ions. On he o he hand, i eleased in he en i onmen , hese plas ic ma e ials can
ep esen a se ious h ea o he en i onmen and ecosys ems. The e o e, hei eco e y
woulda oid hesep oblemsallowing odec easema e ialsex ac ed omnon- enewable
esou ces. In 2020, mo e han 29 M ons o pos -consume plas ic was e we e collec ed
in Eu ope [2]. O hese, mo e han a hi d was ecycled and o e 40% was eco e ed as
ene gy. Howe e , o e 23% o collec ed plas ic was e we e s ill sen o land ill.
I om heonehand plas ic was e ep esen sa aluable esou ce ha canbeemployed
o p oduce new polyme ic ma e ials o manu ac u e plas ic pa s and p oduc s, on he
o he hand he ecycle o such ma e ials p esen s many challenges: i is no always
p ac icable and economically con enien . In ac , pos -consume plas ic lows a e only
pa ially exploi ed [3], and when, in mos cases, hei ecycling is no possible, hey
a e bu ned o gene a e ene gy, his solu ion implying a was e o non- enewable na u al
Inno a i e Building Ma e ials Con aining Pos -Consume Plas ics 89
esou ces. The e o e, al e na i e solu ions a e needed o ully exploi plas ic was e o
p oduce new ma e ials and p oduc s.
3 Valo iza ion o Pos -Consume Plas ic Was e in Cons uc ion
Sec o : Issues
An example o possible ou e o eco e and alo ize he pos -consume plas ic was e is
ep esen ed by hei use in cons uc ion, and in pa icula o p oduce conc e e.
Conside ing ha conc e e is he mos commonly used cons uc ion ma e ial [4], i
pos -consume plas ics, o ins ancepackaginganddisposablei ems,we esys ema ically
employed on an indus ial le el as aw ma e ials o he p oduc ion o conc e e, his
would bene i he en i onmen in se e al ways. This use as aw ma e ials could educe
he use o mine als adi ionally used as agg ega es. Pos -consume plas ic, dispe sed in
small pa icles can, in ac , sa is ac o ily eplace he ine agg ega es, enhancing some
o he inal p ope ies o conc e e. Plas ic was es ha e less weigh pe uni olume
han conc e e agg ega es, he e o e hei use as agg ega es will educe he uni mass o
conc e e s uc u es. The insula ion cha ac e is ic o pos -consume plas ic-conc e e is
also going o inc ease.
Resea ch is e y ac i e in his ield: di e en expe imen al s udies desc ibe, o
ins ance, he use o pos -consume PET bo les in conc e e [5,6]. The conc e es con-
aining PET pa icles as agg ega e a e gene ally epo ed o be e y esis an in bo h
comp ession and lexu e compa ed o con en ional Po land cemen conc e e. The en-
sile s eng h has been ound gene ally inc eased due o he b idging ac ion o plas ic
ibe s in conc e e. Re e ing o wo kabili y o esh conc e e, some li e a u e epo ed an
inc ease in wo kabili y wi h he addi ion o small pe cen ages o was e PET while o h-
e s epo ed an opposi e in luence, p obably due o he di e en shape, size, mechanical
p ope ies and o igin o he was e plas ics. I is gene ally ecognized, howe e , ha i
a p ope mix design is iden i ied, imp o emen s o mechanical and physical p ope ies
can be achie ed in PET-modi ied conc e e. Addi ionally, he was e PET does no equi e
any pa icula ea men be o e he addi ion in conc e e, i.e. nei he cleaning no emo al
o colo s.
On he o he hand, he e a e many aspec s s ill o be analyzed and in es iga ed. Fi s
o all, he cos o p oduc ion o he pos -consume plas ic-conc e e is high, s ill no
compe i i e o con en ional conc e e. I is he e o e necessa y o iden i y applica ions
in which hese new ma e ials can be con enien ly used, i.e. whe e hey a e compe i i e
on he ma ke also in ela ion o hei pe o mance.
Pos -consume plas ic was e ypically con ains di e en ypes o polyme ic ma e-
ials in di e en pe cen ages and wi h di e en shapes. The s eams o pos -consume
plas ics a e, in ac , composed o di e en polyme s, la gely polyole ins (high densi y
and low densi y polye hylene, i.e. HDPE and LDPE, espec i ely, and polyp opylene),
polys y ene, polye hylene e eph hala e (Fig. 1), while he in e na ional scien i ic li -
e a u e mainly analyzes he use o indi idual polyme s (PET only, PE only, e c.) in
conc e e [7]. On he o he hand, he sepa a ion o he di e en polyme s composing
pos -consume plas ic was e is a qui e expensi e p ocess, no always easy o implemen
(di e en polyme s ha e e y simila densi ies). The e o e, i he sepa a ion o di e en
90 M. F igione and J. L. B. de Aguia
ypes o polyme s would be necessa y be o e hei addi ion in o he conc e e, his would
lead o a u he inc ease in p oduc ion cos s. I is he e o e necessa y o e alua e i by
using di e en plas ic was e as agg ega es in conc e e, wi hou hei p io sepa a ion, i is
possible o ob ain conc e es wi h p ope ies and pe o mances compa able o adi ional
conc e es.
Fig. 1. Some plas ic single use con aine s/i ems ha can be ound in pos -consume plas ic
s eams. (PET: polye hylene e eph hala e; PP: polyp opylene; HDPE: high densi y polye hylene;
PS: polys y ene)
4 E ec o Replacing Fine Agg ega e wi h Plas ic Was e
o Di e en Chemical Na u e on he P ope ies o Conc e e
Mul iple s udies in li e a u e illus a e he e ec s on he slump o conc e e due o he
in oduc ion o plas ic was e in eplacemen o agg ega es. Ismail and AL-Hashmi [8]
no iced ha he alues o slump o conc e e mixes con aining plas ic was e (consis ing
o abou 80% PE and 20% PS) ended o dec ease wi h inc easing he was e con en .
This educ ion was a ibu ed o he di e en shapes o he was e pa icles: some we e
angula while o he s had non-uni o m shapes. Simila esul s we e ound also by Rai
e al. [9], as illus a ed in Fig. 2. The s udy s a ed ha he sand in conc e e was pa ially
eplaced by was e plas ic lakes, wi hou speci ying he chemical na u e o he polyme .
The same s udy [9] epo ed ha esh densi y o conc e e dec eased by 5.0%, 8.7%
and 10.7% by eplacing sand wi h 5%, 10% and 15% o plas ic was e, espec i ely. This
beha io can be a ibu ed o he densi y o plas ic was e ha is much lowe (by abou
70%) han ha o sand, esul ing in a educ ion o he esh densi y o conc e e. These
esul s a e in line wi h hose epo ed by Ismail and EL-Hashmi [8]. Figu e 3illus a es
he e ec o an inc ease in he amoun o plas ic was e on he esh densi y o conc e e.
Re e ing o he e ec s on mechanical s eng h o conc e e, Ismail and AL-Hashmi
[8] ound ha he comp essi e s eng h dec eased wi h inc easing he quan i y o plas-
ic was e, i espec i e o he cu ing age o conc e e. This esul , aligned wi h indings
Inno a i e Building Ma e ials Con aining Pos -Consume Plas ics 91
Fig. 2. Slump o conc e e mixes wi h di e en % o plas ic was e [ ep in ed wi h pe mission om
e e ence 9].
Fig. 3. E ec o plas ic was e con en on he esh densi y o conc e e [ ep in ed wi h pe mission
om e e ence 8].
epo ed by o he Au ho s [9], is la gely a ibu ed o he low adhesion s eng h de eloped
be ween he plas ic (PE and PS) pa icles and he cemen pas e. Simila ly, Mus a a and
co-wo ke s [10] ound ha he comp essi e s eng h o he plas ic-conc e e dec eased as
he plas ic con en inc eased. Polyca bona e (PC) pa icles om indus ial was e we e
used in his s udy. The dec ease in s eng h was again mos ly a ibu ed o a low adhesion
be ween he cemen pas e and polyca bona e agg ega e, pa ly o he lowe esis ance
and s i ness ha cha ac e ize he plas ic ma e ial. Figu e 4gi es an example o how he
comp essi e s eng h o conc e e is in luenced by an inc easing addi ion o plas ic was e
o eplace ino ganic agg ega es.
Passing o analyze he ensile s eng h p ope ies, Rahmani e al. [11] s udied he
in luence o he addi ion o PET pa icles, in quan i ies up o 15%, on he ensile s eng h
o conc e es based on wo wa e -cemen a ios, i.e. 0.42 and 0.54, espec i ely. The
PET pa icles we e ob ained by g inding pos -consume bo les. A dec ease in ensile
s eng h was obse ed, again a ibu ed o he limi ed adhesi e s eng h be ween he
plas ic agg ega e and he cemen pas e. Figu e 5p esen s he ensile s eng h alues as
a unc ion o he pe cen age o plas ic was e added o he conc e e, as ound in [11].
Albano and co-wo ke s [12] analyzed he eplacemen o sand wi h PET, up o 20%
by olume, in conc e e wi h wo alues o he wa e -cemen a io, namely 0.50 and 0.60.
92 M. F igione and J. L. B. de Aguia
Fig. 4. Comp essi e s eng h o conc e e as a unc ion o he % o plas ic was e added and he
age o cu ing [ ep in ed wi h pe mission om e e ence 9].
Fig. 5. Tensiles eng ha 28days s. hepe cen ageo plas icwas e,a wo alueso wa e /cemen
a io [ ep in ed wi h pe mission om e e ence 11].
Fig. 6. Spli ing ensile s eng h o Conc e e-PET blends a di e en wa e /cemen a ios
[ ep in ed wi h pe mission om e e ence 12].
The a e age dimensions o he PET pa icles we e 0.26 (small g anules) and 1.14 cm
(la ge g anules); PET came om ecycled-was e bo les. The Au ho s o he s udy ound
Inno a i e Building Ma e ials Con aining Pos -Consume Plas ics 93
ha a dec ease in he spli ing ensile s eng h a a wa e -cemen a io equal o 0.50
compa ed o he e e ence conc e e, ega dless o he size o he PET pa icles. The
dec ease in s eng h was mo e signi ican when he amoun o g ound PET eached 20%,
a ibu ed o he high po osi y o he conc e e a his high amoun o PET. A e y simila
end was also obse ed o a wa e -cemen a io o 0.60: he ensile s eng h alues
dec eased compa ed o he con ol conc e e, e en mo e signi ican . Figu e 6p esen s he
spli ing ensile s eng h alues as a unc ion o he pe cen age o plas ic was e added o
he conc e e, as ound in [12].
Fig. 7. E ec o was e plas ic (con en up o 20%) on lexu al s eng h o conc e e as a unc ion
o he age o cu ing [ ep in ed wi h pe mission om e e ence 8].
Finally, he e ec o he addi ion o plas ic was e on he lexu al s eng h o con-
c e e was e alua ed by Ismail and AL-Hashmi [8]. These Au ho s ound ha he lexu al
s eng h o plas ic was e-conc e e dec eased wi h inc easing he con en o polye hy-
lene/polys y ene pa icles. These esul s a e subs an ially in line wi h hose ound by
Rai e al. [9]. Ha ini and Ramana [13] ound ha he lexu al s eng h dec eased by
inc easing plas ic g anules (PET, less han 4.75 mm in size) in place o ine agg ega e,
i espec i e o he cu ing age. This esul was again a ibu ed o he low bond s eng h
be ween he su ace o he plas ic pa icles and he cemen pas e. The e ec o plas ic
was e on he lexu al s eng h o conc e e is summa ized in Fig. 7.
In all he examples jus illus a ed, he eplacemen o he ine agg ega e in con-
c e e wi h pos -consume plas ic pa icles, based on di e en polyme s, led o a gene al
dec ease in he mechanical p ope ies o conc e e, excep o he e ec o ib ous plas ic
pa icles on lexu al s eng h. This inding was a ibu ed o he poo adhesion ha de el-
ops a he in e ace be ween an o ganic ma e ial, i.e. plas ic pa icles, and an ino ganic
one, i.e. cemen pas e. To sol e his p oblem, se e al solu ions ha e been p oposed. A
i s possibili y in ol es he use o plas ic pa icles wi h speci ic shape, size and aspec
a io. Typically, plas ic ibe s ac as a physical b idge capable o limi ing he p opaga-
ion o ac u es in conc e e. In [14], he Au ho s e ealed ha he geome y o he PET
ibe s can play a signi ican ole in achie ing good mechanical p ope ies o conc e e.
Fo ins ance, ibe s wi h a iable c oss sec ions p oduced a subs an ial imp o emen in
comp essi e s eng h o e s aigh ibe s.
A second possibili y in ol es he modi ica ion o he su ace p ope ies o he plas ic
pa icles so ha hey exe an adequa e adhesi e s eng h o he cemen pas e. This
can be achie ed h ough an app op ia e unc ionaliza ion o he su aces o he plas ic
94 M. F igione and J. L. B. de Aguia
ma e ial,ino de oinc ease hechemicalin e ac ionswi h hecemen pas e: hissolu ion
is mo e e ec i e bu also has highe cos s. An example is illus a ed in he wo k by
Akçaözo˘glu and co-wo ke s [15]. The Au ho s in es iga ed he possibili y o modi y
he su ace o was e PET exposing his polyme o selec ed bac e ial s ains, in o de
o imp o e i s chemical a ini y and adhe ence wi h cemen pas e. These expe imen s
we e success ul: hey ound ha he conc e e p oduced wi h he was e PET exposed o
a bac e ial s ain achie ed g ea e comp essi e and lexu al s eng h alues wi h espec
o conc e e con aining un- ea ed PET.
5 Recen A emp s o Reuse Disposable COVID-19 Masks
in Conc e e
TheCo id19pandemic ha sp eadac oss he globein helas woandahal yea s (2020–
2022) esul ed in a huge en y in o he en i onmen o disposable pe sonal p o ec i e
equipmen (PPE), especially ace masks. The polyme ic ma e ial mainly employed in
he ab ica ion o disposable ace masks is polyp opylene, he mos o masks being eal-
ized in non-wo en ab ic PP. Se e al esea che s ha e p oposed di e en solu ions o
euse/ ecycle he billions o single-use masks con inuously eleased in o he en i on-
men ; some o hem sugges ed o euse hem as agg ega e in conc e e in he wake o
wha has been expe ienced in he las yea s wi h pos -consume plas ics.
In his case, he issues ha a ise a e e en g ea e han hose al eady analyzed. The
ace masks consis o di e en laye s: hey con ain a me allic pa ( o igh en he mask
on he nose) and ubbe ea loops. The di e en ma e ials mus be sepa a ed by disas-
sembling he mask. The second impo an issue is ep esen ed by he possible need o
sani ize he used masks be o e using hem in conc e e. Bo h p ocedu es, ha is he sepa-
a ion o he a ious componen s and hei sani iza ion, in ol e an inc ease in p oduc ion
cos s, jus i ied only by a conside able inc ease in he pe o mance o he conc e e. Sci-
en i ic esea ch is, howe e , p og essing as in he sea ch o a solu ion o his ala ming
en i onmen al p oblem.
Fig. 8. Tensile s eng h a 28 days o conc e e con aining sh edded ace masks [ ep in ed wi h
pe mission om e e ence 16].
Inno a i e Building Ma e ials Con aining Pos -Consume Plas ics 95
The Au ho s o he s udy epo ed in [16] analyzed he e ec o he addi ion o
small amoun s o sh edded ace masks on he mechanical p ope ies o conc e e. They
ound ad an ages in e ms o imp o ed comp essi e s eng h, indi ec ensile s eng h
(as illus a ed in Fig. 8) and modulus o elas ici y by including in conc e e e y small
con en s o masks, i.e. up o 0.2% by olume.
Encou aging esul s we e ecen ly ound also by Ajam and co-wo ke s [17], i.e. an
inc ease in bo h comp essi e and lexu al s eng h upon addi ion in cemen mo a s o
up o 5% in olume o pieces o single use su gical masks.
6 Conclusions: A eas Whe e Fu he Resea ch is Needed
The abo e o e iew has shown ha pos -consume plas ics can be e ec i ely used as
an agg ega e in conc e e, wi h mul iple bene i s o he en i onmen [18,19]. Howe e ,
he e a e s ill many aspec s o be cla i ied o deepened.
The p esence o a andom mix o di e en polyme s in he plas ic was e can lead
o opposi e beha io s in he p ope ies o conc e e. Fu u e esea ch should ocus on
iden i ying composi ions able o achie e adequa e conc e e p ope ies, ega dless o he
ype o polyme s con ained in he was e, possibly playing on he shape and aspec a io
o plas ic ibe s.
New, low-cos and easible me hods mus be de eloped o inc ease he adhesion a
he in e ace be ween he plas ic pa icles and he cemen pas e.
The high cos s o hese new building ma e ials ep esen a limi o hei wide use:
i will be necessa y o iden i y applica ions whe e high cos s a e jus i ied by speci ic
pe o mances.
The li e a u e is e y lacking as ega ds he du abili y o plas ic was e-conc e e: his
gap mus be illed because, in addi ion o he mechanical pe o mance, he du abili y o
he conc e e is an essen ial ea u e o hei ac ual applica ion.
Finally, he e is an u gen need o s anda d codes and upda ed guidelines o eliably
use polyme was e in conc e e.
Re e ences
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Jul. 2022
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pd . Accessed 18 Jul. 2022
3. Adelodun, A.A.: Plas ic eco e y and u iliza ion: om ocean pollu ion o g een economy.
F on . En i on. Sci. 9(683403), 1–12 (2021). h ps://doi.o g/10.3389/ en s.2021.683403
4. Donadka , M.U., Solanke, S.S.: Re iew o e-was e ma e ial used in making o conc e e. In .
J. Sci. Technol. & Eng. 2, 66–69 (2016)
5. Je hy, B., Paul, S., Das, S.K., Adesina, A., Mus akim, S.M.: C i ical e iew on he e olu ion,
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Was e Manage. 24, 435–451 (2022). h ps://doi.o g/10.1007/s10163-022-01362-4
6. Eyni Kanga a , M., Lokuge, W., Manalo, A., Ka unasena, W., F igione, M.: In es iga ion on
he p ope ies o conc e e wi h ecycled polye hylene e eph hala e (PET) g anules as ine
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