Academic Edi o : Rami o Ra ael
Ruiz Rosas
Recei ed: 13 Feb ua y 2025
Re ised: 11 Ma ch 2025
Accep ed: 15 Ap il 2025
Published: 21 Ap il 2025
Ci a ion: Ma ínez, J.D.R.; Ríos, J.D.;
Ci uen es, H.; Lei a, C. Mul i-Scale
Toughening o UHPC: Syne gis ic
E ec s o Ca bon Mic o ibe s and
Nano ubes. Fibe s 2025,13, 49.
h ps://doi.o g/10.3390/
ib13040049
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Licensee MDPI, Basel, Swi ze land.
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A icle
Mul i-Scale Toughening o UHPC: Syne gis ic E ec s o Ca bon
Mic o ibe s and Nano ubes
J. D. Ruiz Ma ínez 1, J. D. Ríos 2, H. Ci uen es 2,* and C. Lei a 1
1Depa men o Chemical and En i onmen al Enginee ing, Escuela Técnica Supe io de Ingenie ía,
Uni e sidad de Se illa, 41092 Se ille, Spain; [email p o ec ed] (J.D.R.M.); [email p o ec ed] (C.L.)
2Depa men o Con inuum Mechanics and S uc u al Analysis, Escuela Técnica Supe io de Ingenie ía,
Uni e sidad de Se illa, 41092 Se ille, Spain; [email p o ec ed]
*Co espondence: [email p o ec ed]
Highligh s
Wha a e he main indings?
•
Ul a-High Pe o mance Conc e e (UHPC) was ein o ced a mul iple scales using
ca bon mic o ibe s and ca bon nano ubes wi hou comp omising wo kabili y.
•
This hyb id ein o cemen inc eased comp essi e s eng h by 39%, ensile s eng h by
313%, and educed mac opo osi y by 42%.
Wha is he implica ion o he main inding?
•The mul i-scale ein o cemen imp o es UHPC du abili y and ac u e esis ance.
•
The ca bon-based ein o cemen o e s a co osion- ee al e na i e o o sho e and
ma ine s uc u es.
Abs ac : This s udy in es iga es mul i-scale ein o cemen o Ul a-High-Pe o mance
Conc e e h ough a ge ed modi ica ions o i s mechanical and ac u e- esis an p ope ies
ia ca bon mic o ibe s and ca bon nano ubes. The esea ch employed comp ehensi e cha -
ac e iza ion echniques including wo kabili y es s, me cu y po osime y o mic oscale
po osi y analysis, and X- ay omog aphy o mac o-scale po e e alua ion. Mechanical
pe o mance was assessed h ough comp ession s eng h, ensile s eng h, and ac u e
ene gy measu emen s. Resul s demons a ed signi ican pe o mance enhancemen s es -
ing UHPC samples wi h 6 mm ca bon mic o ibe s (9 kg/m
3
) and a ying ca bon nan-
o ubes dosages (
0.11–0.54 w %
). The addi ion o ca bon mic o ib es imp o ed comp essi e
s eng h by 12%, while inco po a ing 0.54 w % ca bon nano ubes u he inc eased s eng h
by 24%. Rema kably, he combined ein o cemen s a egy yielded a 313% inc ease in
ensile s eng h compa ed o he e e ence mix u e. The syne gis ic e ec o ca bon ibe s
and ca bon nano ubes p o ed pa icula ly e ec i e in enhancing conc e e pe o mance.
This mul i-scale ein o cemen app oach p esen s a p omising al e na i e o adi ional
s eel ibe ein o cemen , o e ing supe io mechanical p ope ies and po en ial ad an ages
in co osi e en i onmen s.
Keywo ds: ul a-high-pe o mance ibe - ein o ced conc e e; he mog a ime ic analysis;
ca bon mic o ibe ; ca bon nano ubes; ibe –ma ix in e ac ion
1. In oduc ion
Ul a-High-Pe o mance Conc e e (UHPC) is one o he mos ep esen a i e cemen -
based composi e ma e ials, cha ac e ized by i s high comp essi e s eng h, ema kable
Fibe s 2025,13, 49 h ps://doi.o g/10.3390/ ib13040049
Fibe s 2025,13, 49 2 o 20
ensile s eng h, and excellen du abili y. UHPC is dis inguished by a wa e /cemen a io
o en below 0.2 and he in eg a ion o e y ine cemen i ious ma e ials and supplemen a y
agg ega es o p omo e he hyd a ion p ocess and o m a low po osi y s uc u e [
1
–
7
].
This me iculous composi ion esul s in a dense ma ix ha minimizes po en ial ailu e
poin s o e he li e o he ma e ial [
6
–
8
]. The inco po a ion o sho ibe s such as s eel,
ca bon, glass, PVA, and polyp opylene ibe s among he mos used is a s a egic esponse o
imp o e duc ili y, ene gy abso p ion, and ensile s eng h [
9
–
13
]. These ibe s a e essen ial
o c ack esis ance, as hey ac as a uni ying o ce ac oss c acks [13–16].
Ca bon ibe (CF)- ein o ced UHPC has eme ged as a p omising ma e ial o ad anced
s uc u al applica ions, especially in ma ine en i onmen s. Simila ly o o he ibe s, he
inclusion o CF can b idge mic o-c acks in UHPC, allowing he ma e ial o con inue o
suppo he load a e c acking due o he high s eng h o he bond be ween he ca bon
ibe and he cemen -based ma e ial [
17
,
18
]. The op imal leng h o CFs in UHPC ypically
anges om 3 o 6 mm, which allows o imp o ed dispe sion [
17
,
19
]. CF ein o cemen
o UHPC o e s se e al ad an ages o e adi ional s eel ibe s, such as highe ensile
s eng h, co osion esis ance, lowe diame e , and lowe weigh [
17
,
20
,
21
]. This makes
i pa icula ly sui able o o sho e wind u bine ounda ions, whe e esis ance o ha sh
ma ine condi ions is c ucial [
19
,
21
]. The non-co osi e na u e o CFs elimina es he isk o
ein o cemen deg ada ion in sal wa e en i onmen s, which can ex end he li e o o sho e
s uc u es [
19
,
21
]. In addi ion, he use o ecycled CFs in UHPC has shown p omise
o cos educ ion and imp o ed sus ainabili y, while main aining a ac i e mechanical
p ope ies [17].
Nano echnology has e olu ionized he de elopmen o UHPC, eme ging as p omis-
ing ein o cemen ma e ial [
22
–
24
]. Nanoma e ials signi ican ly in luence UHPC’s mi-
c os uc u al de elopmen and pe o mance cha ac e is ics. Thei e ec i eness as ein-
o cemen depends on mul iple ac o s including mo phology, dimensions, su ace cha -
ac e is ics, bond s eng h wi h he ma ix, and capaci y o c ack con ol and ene gy ab-
so p ion [
24
]. The de e io a ion p ocess in cemen i ious ma e ials ypically begins wi h
nanoc acks, which p og essi ely de elop in o mic o- and mac oscale de ec s, comp omising
bo h mechanical p ope ies and du abili y [
24
,
25
]. Recen ad ances in conc e e echnol-
ogy ha e explo ed a ious nanoma e ials including ca bon nano ubes (CNT), g aphi e
nanopla ele s (GNP), nano silica (NS), Al
2
O
3
nano ibe (ANF), and g aphene oxide (GO),
among o he s. These ma e ials, when op imally inco po a ed, enhance bo h mechanical
p ope ies and ma ix densi y h ough dis inc mechanisms. Ine nano addi i es unc ion
ia nuclea ion, illing, and b idging e ec s, while ac i e nanoma e ials p o ide hese bene-
i s while also accele a ing hyd a ion kine ics. Howe e , ca e ul dosage con ol is c ucial,
as excessi e quan i ies can lead o agglome a ion and educed wo kabili y, ul ima ely
inc easing po osi y [23,26,27].
Rega ding CNTs, Jung e al. [
28
] e alua ed he impac o dispe sed mul i-wall CNTs on
he comp essi e s eng h and elas ic modulus o UHPCS, inding bo h app oaches e ec i e.
Elec ically cu ed UHPC wi h 1.2 w % CNTs achie ed he highes comp essi e s eng h
and elas ic modulus, 8.6% and 17.1% highe , espec i ely, compa ed o s eam-cu ed UHPC
wi hou CNTs. I was also ound ha he inco po a ion o CNTs enhanced he s eng h
o conc e e by c ea ing b idges be ween hyd a ion p oduc s and o ming c oss-linked
ne wo ks wi hin he C–S–H silica e chains, hus limi ing mic oc ack de elopmen [
29
]. This
imp o emen is a ibu ed o CNTs s eng hening hyd a ion p oduc s and o ming dense
C–S–H agglome a es wi h highe s i ness and illing mac o and mic o-po es [
26
,
30
,
31
].
Viana e al. [
32
] obse ed s eng h inc eases a CNT dosages o 0.05–0.1% by weigh o
cemen , while Zhang e al. [
33
] epo ed simila ends o dosages up o 0.05%. CNTs
also enhance esidual s eng h and educe spalling a high empe a u es (up o 300
◦
C)
Fibe s 2025,13, 49 3 o 20
by c ea ing po e s uc u es ha allow apo escape and by ein o cing he ma ix. Ozone-
ea ed CNTs imp o ed UHPC comp essi e s eng h by 30.6% and 9.8% a 1 and 28 days,
espec i ely, a a dosage o 0.1 w % [
34
]. Ruan e al. [
35
] epo ed inc eased s eng h and
oughness wi h CNT dosages up o 0.5%, ega dless o leng h a ia ions. Rega ding he
impo ance o CNT dispe sion, Chen e al. [
30
] s a e ha poo dispe sion causes de ec s and
inc eases po osi y and p opose ul a-sonic dispe sion as a solu ion. Ul asonic Dispe sed
CNTs (0.25–0.5%) enhanced dynamic comp essi e s eng h, impac oughness, and ene gy
dissipa ion unde high s ain a es (200–800/s), wi h imp o emen s o 68.9–71.0% a 0.5%
dosage [36].
The UHPC de eloped in his s udy has signi ican po en ial o a wide ange o
s uc u al applica ions, pa icula ly hose equi ing high s eng h, du abili y, and esis ance
o ha sh en i onmen s. Key applica ions include o sho e and ma ine s uc u es (e.g., wind
u bine ounda ions and coas al b idges), blas - and impac - esis an buildings, long-span
b idges, high- ise buildings, p ecas conc e e elemen s, and seismic- esis an s uc u es.
The non-co osi e na u e and ligh weigh p ope ies o CFs and CNTs make his ma e ial
pa icula ly sui able o sus ainable in as uc u e p ojec s, whe e du abili y and educed
main enance a e c i ical [21].
This s udy in es iga es he mul iscale in e ac ion be ween CNTs and ca bon mi-
c o ibe s in enhancing UHPC. By es ing UHPC samples wi h 6 mm CFs and a ying
CNT dosages, we e alua ed mechanical p ope ies and ac u e beha io , linking ibe and
nanopa icle e ec s o ma ix po e s uc u e and o e all pe o mance. Ad anced X- ay
compu ed omog aphy and me cu y in usion po osime y p o ided da a o he in e nal
po e ne wo k, while scanning elec on mic oscopy (SEM) e ealed de ailed insigh s in o
he ibe –conc e e in e ace and ailu e mechanisms. Combining hese analyses wi h me-
chanical es ing, i was possible o iden i y how mic os uc u al changes d i en by ibe
ein o cemen imp o e he s eng h and du abili y o UHPC.
2. Ma e ials and Me hods
2.1. Ma e ials
Figu e 1illus a es he ma e ials used in his s udy, including cemen , silica ume,
agg ega es, ca bon ibe s (CF), and ca bon nano ubes (CNTs). Th ee componen s ha e been
used as binde ma e ials in his s udy: Type I cemen 52.5 R/SR, manu ac u ed by Po land
Valde ibas; silica ume (SF) S-92-D p o ided by SIKA; as well A celo -Mi al’s g ound
g anula ed slag (GGS). Rega ding agg ega es, wo ypes o qua z sand wi h di e en g ain
sizes ha e been used. Fine sand (FS) has a maximum g ain size o 0.315 mm, while coa se
sand (CS) is less han 0.800 mm.
To analyze he chemical composi ion o he cemen ma e ials, an X- ay luo escence
spec ome e was used. The esul s showed ha he mos abundan compounds we e
calcium oxide (CaO) and silicium dioxide (SiO
2
); he emaining compounds and hei
p opo ions a e de ailed in Table 1. A supe plas ic (20HE) om Sika has also been inco po-
a ed. Ca bon mic o ibe s o he ype TenaxTM HTC124, p o ided by Teijin CF, we e used
wi h he ollowing cha ac e is ics: a diame e o 7
µ
m, a leng h o 6 mm, a ensile s eng h
(
) o 4200 MPa, and a Young’s modulus (E) o 230 GPa. Ca bon nano ibe s (CNTs) om
Sigma-Ald ich we e used, wi h he ollowing cha ac e is ics: a diame e o 100
µ
m and a
leng h mos ly wi hin he ange o 20 o 80 µm.
Fibe s 2025,13, 49 4 o 20
Fibe s 2025, 13, x FOR PEER REVIEW 4 o 23
Figu e 1. Ma e ials used in he UHPC o mula ions.
Table 1. Chemical composi ion by FRX o he bonding ma e ials.
Po land Cemen GGBS SF
Al
2
O
3
6.59 9.83 0.20
BaO 0.06 - -
CaO 45.61 35.12 0.30
Cl
2
O
3
0.07 - -
CuO 0.04 - -
Fe
2
O
3
2.85 0.31 0.06
K
2
O
2
1.09 2.01 0.42
MgO 1.00 6.63 0.35
MnO
2
0.05 0.11 -
NaO
2
0.29 0.21 0.12
P
2
O
5
0.13 - -
SiO
2
18.29 27.81 79.58
SO
3
4.02 - -
S O 0.05 0.08 -
TiO
2
0.41 0.48 -
ZnO 0.02 - -
2.2. Mix P opo ions and Specimen P epa a ion
Fi e dis inc mix u es o UHPC we e de eloped, as shown in Table 2. The CF dosage
was chosen based on p io s udies [37], as i p o ides an op imal balance be ween wo k-
abili y, po osi y, and mechanical pe o mance. Highe CF con en s end o educe
Figu e 1. Ma e ials used in he UHPC o mula ions.
Table 1. Chemical composi ion by FRX o he bonding ma e ials.
Po land Cemen GGBS SF
Al2O36.59 9.83 0.20
BaO 0.06 - -
CaO 45.61 35.12 0.30
Cl2O30.07 - -
CuO 0.04 - -
Fe2O32.85 0.31 0.06
K2O21.09 2.01 0.42
MgO 1.00 6.63 0.35
MnO20.05 0.11 -
NaO20.29 0.21 0.12
P2O50.13 - -
SiO218.29 27.81 79.58
SO34.02 - -
S O 0.05 0.08 -
TiO20.41 0.48 -
ZnO 0.02 - -
2.2. Mix P opo ions and Specimen P epa a ion
Fi e dis inc mix u es o UHPC we e de eloped, as shown in Table 2. The CF dosage
was chosen based on p io s udies [
37
], as i p o ides an op imal balance be ween wo kabil-
i y, po osi y, and mechanical pe o mance. Highe CF con en s end o educe wo kabili y,
Fibe s 2025,13, 49 5 o 20
while lowe dosages o e limi ed mechanical bene i s. In con as , he CNT dosage was
a ied o assess i s e ec on mic os uc u al e inemen and mechanical p ope ies, ensu ing
p ope dispe sion h ough p elimina y ials The e ec o bo h mic o ibe s and CNTs was
analyzed ac oss he di e en o mula ions. The o al solid con en in he ma ix was he
same o all mix u es. The amoun o CF (9 kg/m
3
) emained he same in ou ou o he
i e mixes, bu di e en concen a ions o CNT we e used (0, 0.11, 0.32 and 0.54 kg/m
3
).
The mix u es we e named Dn-m, whe e nis he dosage o mic o ibe (kg/m
3
), and mis he
dosage o nano ubes (kg/m
3
), esul ing in he ollowing o mula ions: D0-0, D9-0, D9-0.11,
D9-0.32, D9-0.54.
Table 2. Componen s and composi ions o all mix u es (kg/m3).
Componen
(kg/m3)/Mix u e D0-0 D9-0 D9-0.11 D9-0.32 D9-0.54
Cemen 540.07 540.07 540.07 540.07 540.07
Silica Fume 210.09 210.09 210.09 210.09 210.09
GGS 310.02 310.02 310.02 310.02 310.02
FS 470 470 470 470 470
CS 470 470 470 470 470
Wa e 199.33 199.33 199.33 199.33 199.33
Supe plas icize 44.4 44.4 44.4 44.4 44.4
CF - 9 9 9 9
CNT - - 0.11 0.32 0.54
In he i s s age, he solid componen s (cemen , SF, GGBS, FS, and CS) we e placed
in o a e ical mixe and mixed o 5 min. In a pa allel way, he wa e , supe plas icize ,
and ca bon nano ibe s we e sonica ed using an Ul aSons 300515 ul asound de ice o
15 min
o ob ain a homogeneous liquid mix u e; his ime was de e mined o be op imal in
e ms o dispe sion in p e ious s udies [
38
]. Subsequen ly, he solid and liquid componen s
we e combined and mixed o 20 min. Finally, he CFs we e added and mixed o 5 min o
achie e he app op ia e consis ency. Th ee p isms (40
×
40
×
160 mm
3
) we e manu ac u ed
om each mix u e (Figu e 2). Fo each mix, six specimens we e es ed, p epa ed in wo
sepa a e ba ches o e i y ep oducibili y and ensu e consis en esul s. A e 24 h, he
samples we e emo ed om he molds and subjec ed o a wa e cu ing p ocess a oom
empe a u e o 28 days. Then, he samples we e le o d y o 24 h be o e being es ed.
2.3. Expe imen al P og am
2.3.1. Wo kabili y
To e alua e he wo kabili y o esh conc e e, a minia u ized slump es was conduc ed
ollowing he p ocedu es ou lined in he EN 12350-2:2020 s anda d [
39
]. The es se up u i-
lized a modi ied Ab ams cone wi h dimensions o 50 mm a he op, 100 mm a he bo om,
and 150 mm in heigh , aligning wi h he me hodology desc ibed by Nguyen e al. [40].
2.3.2. Po e Size Dis ibu ion Th ough X-Ray Compu ed Scan and Me cu y Po osime y
X- ay compu ed omog aphy was employed o e alua e mac os uc u al modi ica ions
induced by he inco po a ion o CFs and CNTs. The in es iga ion u ilized a YXLON Y.
Couga SMT X- ay sys em, loca ed a he Uni e si y o Se ille’s X- ay Cha ac e iza ion
Se ice. The expe imen al p o ocol in ol ed scanning h ee ep esen a i e samples o
each conc e e mix u e, gene a ing a o al o 12 CT scans. S a is ical analysis cap u ed
he mean alues and mic os uc u al de ia ion. Sample dimensions we e s anda dized
a
8×8×4 mm3
. Po e cha ac e iza ion was conduc ed using D agon ly so wa e ( e -
sion 2022.2), which di e en ia es conc e e ma ix cons i uen s based on hei inhe en
Fibe s 2025,13, 49 6 o 20
densi y a ia ions. A comp ehensi e me hodology o po osi y analysis ia X- ay CT
has been p e iously documen ed by Ríos e al. [
8
,
41
]. Gi en he speci ic expe imen al
condi ions—equipmen speci ica ions, conc e e ypology, and sample geome y— he X- ay
measu emen p ecision was es ima ed a app oxima ely 40 µm.
Fibe s 2025, 13, x FOR PEER REVIEW 6 o 23
Figu e 2. Manu ac u ed specimens be o e being es ed.
2.3. Expe imen al P og am
2.3.1. Wo kabili y
To e alua e he wo kabili y o esh conc e e, a minia u ized slump es was con-
duc ed ollowing he p ocedu es ou lined in he EN 12350-2:2020 s anda d [39]. The es
se up u ilized a modi ied Ab ams cone wi h dimensions o 50 mm a he op, 100 mm a
he bo om, and 150 mm in heigh , aligning wi h he me hodology desc ibed by Nguyen
e al. [40].
2.3.2. Po e Size Dis ibu ion Th ough X-Ray Compu ed Scan and Me cu y Po osime y
X- ay compu ed omog aphy was employed o e alua e mac os uc u al modi ica-
ions induced by he inco po a ion o CFs and CNTs. The in es iga ion u ilized a YXLON
Y. Couga SMT X- ay sys em, loca ed a he Uni e si y o Se ille’s X- ay Cha ac e iza ion
Se ice. The expe imen al p o ocol in ol ed scanning h ee ep esen a i e samples o
each conc e e mix u e, gene a ing a o al o 12 CT scans. S a is ical analysis cap u ed he
mean alues and mic os uc u al de ia ion. Sample dimensions we e s anda dized a 8 ×
8 × 4 mm3. Po e cha ac e iza ion was conduc ed using D agon ly so wa e ( e sion
2022.2), which diffe en ia es conc e e ma ix cons i uen s based on hei inhe en densi y
a ia ions. A comp ehensi e me hodology o po osi y analysis ia X- ay CT has been
p e iously documen ed by Ríos e al. [8,41]. Gi en he speci ic expe imen al condi ions—
equipmen speci ica ions, conc e e ypology, and sample geome y— he X- ay measu e-
men p ecision was es ima ed a app oxima ely 40 µm.
Fo smalle po osi y measu emen s, po osime y was conduc ed using a Mic ome i -
ics Au opo e IV 9500 me cu y in usion po osime e (No c oss, GA, Uni ed S a ed o
Ame ica). The analysis encompassed a comp ehensi e po e size ange om 0.007 µm o
150 µm, enabling de ailed cha ac e iza ion o he ma e ial’s mic os uc u al p ope ies.
Sample p epa a ion in ol ed ob aining 5 mm diame e cylind ical pelle s, which we e
subsequen ly subjec ed o con olled he mal d ying in a labo a o y o en. Specimens we e
Figu e 2. Manu ac u ed specimens be o e being es ed.
Fo smalle po osi y measu emen s, po osime y was conduc ed using a Mic ome i -
ics Au opo e IV 9500 me cu y in usion po osime e (No c oss, GA, USA). The analysis
encompassed a comp ehensi e po e size ange om 0.007
µ
m o 150
µ
m, enabling de ailed
cha ac e iza ion o he ma e ial’s mic os uc u al p ope ies. Sample p epa a ion in ol ed
ob aining 5 mm diame e cylind ical pelle s, which we e subsequen ly subjec ed o con-
olled he mal d ying in a labo a o y o en. Specimens we e main ained a a cons an
empe a u e o 105
◦
C un il achie ing a s able mass, ensu ing consis en and ep oducible
analy ical condi ions.
2.3.3. The mog a ime ic Analysis (TGA)
The mog a ime ic cha ac e iza ion was pe o med u ilizing a Me le -Toledo TG-
SDTA 851 he mog a ime ic analyze (Columbus, OH, USA), examining ma e ial ans-
o ma ions ac oss a empe a u e spec um anging om ambien condi ions o 1000
◦
C.
Su ace-ex ac ed specimens, ca e ully selec ed wi h masses be ween 100 and 150 mg,
unde wen comp ehensi e he mal analysis. The expe imen al p o ocol employed a mo-
sphe ic ai as pu ge gas, main aining a consis en hea ing p og ession o 10
◦
C pe minu e
o ensu e sys ema ic and con olled he mal e alua ion.
2.3.4. Scanning Elec on Mic oscopy (SEM)
In o de o be e unde s and he ole o de ec s, pa icula ly hose ha may be p e-sen
a he ibe /ma ix in e ace and he in luence o he CF, a sample was analyzed wi h a
Hi achi S5200 scanning elec on mic oscope (SEM, Tokyo, Japan).
Fibe s 2025,13, 49 7 o 20
2.3.5. Mechanical P ope ies
Comp essi e S eng h
Comp essi e s eng h e alua ion was conduc ed on six specimens o each mix u e
con igu a ion, wi h s anda dized dimensions o 80
×
40
×
40 mm
3
. Tes ing p ocedu es
s ic ly adhe ed o he EN 12390-3 s anda d [
42
]. A se o-hyd aulic es ing appa a us
wi h a 3000 kN load capaci y was employed o execu e he comp ehensi e mechanical
cha ac e iza ion.
Tensile S eng h
A h ee-poin bending es was conduc ed on p isma ic specimens measu ing 40
×
40
×
160 mm
3
, ollowing he RILEM TCM-85 [
43
] p o ocol, o de e mine ac u e wo k
and ac u e ene gy. Mechanical es ing was pe o med u ilizing a se o-hyd aulic es ing
sys em con igu ed wi h a maximum load capaci y o 200 kN, employing C ack Mou h
Opening Displacemen (CMOD) as he p ima y displacemen con ol mechanism. To
mi iga e po en ial o sional de o ma ion and ensu e expe imen al p ecision, an i- o sion
s abiliza ion de ices we e s a egically implemIen ed on bo h he loading and suppo
olle s. The no ch geome y was s anda dized wi h a leng h- o-dep h a io o one-six h o
all es specimens (Figu e 3). No e ha he bilinea app oxima ion o he ension-so ening
diag am (Figu e 4) yields a alue o he conc e e’s di ec ensile s eng h ( ).
Fibe s 2025, 13, x FOR PEER REVIEW 8 o 23
Figu e 3. Th ee-poin bending es .
Figu e 4. Bilinea cohesi e law o ac u e p ocess.
F ac u e Beha io
F ac u e ene gy and cohesi e law pa ame e s we e ob ained h ough in e se analy-
sis. The in e se analy ical me hodology in ol ed i e a i ely calib a ing cohesi e law pa-
ame e s o op imize he co espondence be ween expe imen ally de i ed load–CMOD
cu es and he heo e ical cohesi e model’s load–CMOD ep esen a ion (Figu e 4). Based
on he non-linea hinge model [44,45], he cohesi e law was concep ualized as a bi-linea
amewo k, s a egically segmen ed in o wo dis inc b anches: he i s b anch cha ac e -
ized by ac u e ene gy – yellow colo – (G ), and he second b anch de ined by he esidual
ac u e ene gy –blue colo – (GF−G ).
3. Resul s and Discussion
3.1. The mog a ime ic Analysis
The mog a ime ic analysis (TGA) was pe o med on D9-0 and D9-0.32 samples o
examine ma e ial ans o ma ions wi h and wi hou nano ibe addi ion. Figu e 5 illus-
a es he he mog a ime ic and diffe en ial he mog a ime ic cu es om ambien
Figu e 3. Th ee-poin bending es .
F ac u e Beha io
F ac u e ene gy and cohesi e law pa ame e s we e ob ained h ough in e se analysis.
The in e se analy ical me hodology in ol ed i e a i ely calib a ing cohesi e law pa ame-
e s o op imize he co espondence be ween expe imen ally de i ed load–CMOD cu es
and he heo e ical cohesi e model’s load–CMOD ep esen a ion (Figu e 4). Based on he
non-linea hinge model [
44
,
45
], he cohesi e law was concep ualized as a bi-linea ame-
wo k, s a egically segmen ed in o wo dis inc b anches: he i s b anch cha ac e ized
Fibe s 2025,13, 49 8 o 20
by ac u e ene gy—yellow colo —(G
), and he second b anch de ined by he esidual
ac u e ene gy—blue colo —(GF−G ).
Fibe s 2025, 13, x FOR PEER REVIEW 8 o 23
Figu e 3. Th ee-poin bending es .
Figu e 4. Bilinea cohesi e law o ac u e p ocess.
F ac u e Beha io
F ac u e ene gy and cohesi e law pa ame e s we e ob ained h ough in e se analy-
sis. The in e se analy ical me hodology in ol ed i e a i ely calib a ing cohesi e law pa-
ame e s o op imize he co espondence be ween expe imen ally de i ed load–CMOD
cu es and he heo e ical cohesi e model’s load–CMOD ep esen a ion (Figu e 4). Based
on he non-linea hinge model [44,45], he cohesi e law was concep ualized as a bi-linea
amewo k, s a egically segmen ed in o wo dis inc b anches: he i s b anch cha ac e -
ized by ac u e ene gy – yellow colo – (G ), and he second b anch de ined by he esidual
ac u e ene gy –blue colo – (GF−G ).
3. Resul s and Discussion
3.1. The mog a ime ic Analysis
The mog a ime ic analysis (TGA) was pe o med on D9-0 and D9-0.32 samples o
examine ma e ial ans o ma ions wi h and wi hou nano ibe addi ion. Figu e 5 illus-
a es he he mog a ime ic and diffe en ial he mog a ime ic cu es om ambien
Figu e 4. Bilinea cohesi e law o ac u e p ocess.
3. Resul s and Discussion
3.1. The mog a ime ic Analysis
The mog a ime ic analysis (TGA) was pe o med on D9-0 and D9-0.32 samples o
examine ma e ial ans o ma ions wi h and wi hou nano ibe addi ion. Figu e 5illus a es
he he mog a ime ic and di e en ial he mog a ime ic cu es om ambien empe -
a u e o 1000
◦
C. Th ee dis inc he mal decomposi ion peaks we e iden i ied wi hin he
empe a u e anges o 100–200
◦
C, 400–500
◦
C, and 500–600
◦
C, e ealing he cha ac e is ic
ma e ial esponse o p og essi e he mal loading.
Fibe s 2025, 13, x FOR PEER REVIEW 9 o 23
empe a u e o 1000 °C. Th ee dis inc he mal decomposi ion peaks we e iden i ied
wi hin he empe a u e anges o 100–200 °C, 400–500 °C, and 500–600 °C, e ealing he
cha ac e is ic ma e ial esponse o p og essi e he mal loading.
Figu e 5. TGA compa ison o UHPC ein o ced wi h CFs and CNTs.
The ini ial he mal peak (100–200 °C) ep esen s mois u e and capilla y wa e e ap-
o a ion, alongside C–S–H gel dehyd a ion. CNTs a e chemically inac i e and do no pa -
icipa e in hyd a ion eac ions, bu hei inco po a ion se es as nuclea ion si es o he
o ma ion o dense C–S–H s uc u es while simul aneously illing po es a mul iple scales
[26,46], he eby accele a ing he de elopmen o hyd a ion p oduc s, including C–S–H
and calcium hyd oxide.
The second mass loss eac ion occu s be ween 500 °C and 600 °C, co esponding o
he dihyd oxyla ion o calcium hyd oxide (Ca(OH)
2
). This s age exhibi s a 0.53% mass loss
a ia ion, showing ha CNT addi ion sligh ly inc eases mass loss due o a highe concen-
a ion o Ca(OH)
2
, he main pozzolanic eac an (wi h ly ash, SF, o GGBS) in he o -
ma ion o addi ional C–S–H gel [47]. These ou comes a e in line wi h Fu e al. [48], who
epo ed ha he p opo ions o gel po es and innocuous capilla ies, as well as he amoun
o hexagonal p isma ic Ca(OH)
2
, ose wi h he addi ion o CNTs.
In he hi d s age, e e ing o calcium ca bona e (CaCO
3
) decomposi ion, he same
end is obse ed bu wi h a less signi ican 0.3% mass loss a ia ion. Again, he D9-0.54
mix shows a mo e p onounced peak due o i s highe CaCO
3
concen a ion, which helps
densi y he conc e e [49]. Reac ions a e 700 °C ela e o he loss o esidual hyd oxides,
and he e is no signi ican diffe ence be ween he mixes eaching he same mass loss o-
wa ds he end o he TGA [50].
3.2. Wo kabili y
The esul s assessing he wo kabili y o each mix u e a e shown in Figu e 6. The e-
sul s indica ed a clea end: he inclusion o CFs led o a educ ion in slump diame e .
Mo eo e , he esul s demons a ed ha inc easing he ca bon nano ube dosage esul ed
in lowe wo kabili y.
Figu e 5. TGA compa ison o UHPC ein o ced wi h CFs and CNTs.
The ini ial he mal peak (100–200
◦
C) ep esen s mois u e and capilla y wa e e ap-
o a ion, alongside C–S–H gel dehyd a ion. CNTs a e chemically inac i e and do no
pa icipa e in hyd a ion eac ions, bu hei inco po a ion se es as nuclea ion si es o
he o ma ion o dense C–S–H s uc u es while simul aneously illing po es a mul i-
ple scales [
26
,
46
], he eby accele a ing he de elopmen o hyd a ion p oduc s, including
C–S–H and calcium hyd oxide.
Fibe s 2025,13, 49 9 o 20
The second mass loss eac ion occu s be ween 500
◦
C and 600
◦
C, co esponding o
he dihyd oxyla ion o calcium hyd oxide (Ca(OH)
2
). This s age exhibi s a 0.53% mass
loss a ia ion, showing ha CNT addi ion sligh ly inc eases mass loss due o a highe
concen a ion o Ca(OH)
2
, he main pozzolanic eac an (wi h ly ash, SF, o GGBS) in he
o ma ion o addi ional C–S–H gel [
47
]. These ou comes a e in line wi h Fu e al. [
48
], who
epo ed ha he p opo ions o gel po es and innocuous capilla ies, as well as he amoun
o hexagonal p isma ic Ca(OH)2, ose wi h he addi ion o CNTs.
In he hi d s age, e e ing o calcium ca bona e (CaCO
3
) decomposi ion, he same
end is obse ed bu wi h a less signi ican 0.3% mass loss a ia ion. Again, he D9-0.54 mix
shows a mo e p onounced peak due o i s highe CaCO
3
concen a ion, which helps densi y
he conc e e [
49
]. Reac ions a e 700
◦
C ela e o he loss o esidual hyd oxides, and he e
is no signi ican di e ence be ween he mixes eaching he same mass loss owa ds he end
o he TGA [50].
3.2. Wo kabili y
The esul s assessing he wo kabili y o each mix u e a e shown in Figu e 6. The
esul s indica ed a clea end: he inclusion o CFs led o a educ ion in slump diame e .
Mo eo e , he esul s demons a ed ha inc easing he ca bon nano ube dosage esul ed in
lowe wo kabili y.
Fibe s 2025, 13, x FOR PEER REVIEW 10 o 23
Figu e 6. Wo kabili y slump es .
As depic ed in Figu e 4, he inco po a ion o CF leads o a 9% educ ion in wo kabil-
i y. This phenomenon can be a ibu ed o he CF’s abili y o c ea e a signi ican ly dense
ma ix, which la gely explains he mo e subs an ial wo kabili y educ ion. The wo kabil-
i y loss becomes less p onounced wi h CNT addi ion, anging om 11% o 14% ela i e
o he e e ence mix u e (D0-0). The i egula mo phology o ca bon nano ubes con ib-
u es o enhanced in e -componen cohesion wi hin he mix u e. Ne e heless, i is no e-
wo hy ha all in es iga ed mix designs main ain sel -compac ing cha ac e is ics (>28
cm), demons a ing hei inhe en abili y o ill molds h ough g a i a ional o ces alone,
wi hou he need o ex e nal compac ion.
3.3. Po e Size Dis ibu ion Th ough X-Ray Compu ed Scan and Me cu y In usion
Po osime y (MIP)
X- ay omog aphy can size a ange o mac opo osi y be ween 0.100 mm and 5 mm
[41]. As shown in Figu e 7, he conc e e ma ices exhibi mac opo e dis ibu ions anging
be ween 0.1 and 1.5 mm. The inco po a ion o CFs subs an ially educed he quan i y o
mac opo es wi hin he ma e ial ma ix, while he addi ion o CNTs esul ed in a esidual
dec ease in o al mac opo osi y.
Figu e 6. Wo kabili y slump es .
As depic ed in Figu e 4, he inco po a ion o CF leads o a 9% educ ion in wo kabili y.
This phenomenon can be a ibu ed o he CF’s abili y o c ea e a signi ican ly dense ma ix,
which la gely explains he mo e subs an ial wo kabili y educ ion. The wo kabili y loss
becomes less p onounced wi h CNT addi ion, anging om 11% o 14% ela i e o he
e e ence mix u e (D0-0). The i egula mo phology o ca bon nano ubes con ibu es o
enhanced in e -componen cohesion wi hin he mix u e. Ne e heless, i is no ewo hy
ha all in es iga ed mix designs main ain sel -compac ing cha ac e is ics (>28 cm), demon-
s a ing hei inhe en abili y o ill molds h ough g a i a ional o ces alone, wi hou he
need o ex e nal compac ion.
Fibe s 2025,13, 49 16 o 20
dense and s onge cemen ma ix. These indings ad ance he unde s anding o how CFs
and CNTs can be op imally combined o enhance he pe o mance o conc e e in demanding
enginee ing applica ions.
On he o he hand, he inco po a ion o ibe s is a c ucial ac o in enhancing he
mechanical p ope ies o UHPC. S eel ibe s a e widely used due o hei high ensile
s eng h and c ack-b idging capabili y [
57
]. S udies indica e ha inc easing SF con en om
1% o 3% imp o es he comp essi e s eng h (up o 164 MPa) and signi ican ly enhances
ensile and lexu al p ope ies. Howe e , s eel ibe s a e he mos commonly used ibe s
in UHPC. The inco po a ion o s eel ibe s in UHPC has some disad an ages, such as
he po en ial o co ode, high densi y (which adds cons an load), high cos , and, a high
dosages (>4%), SF can lead o wo kabili y issues and ibe agglome a ion, which may
nega i ely impac mechanical pe o mance [
57
–
59
]. This makes i pa icula ly unsui able
o o sho e wind u bine ounda ions, whe e esis ance o ha sh ma ine condi ions is
c ucial Addi ionally, SF- ein o ced UHPC exhibi s ac u e ene gy alues anging be ween
200 and 300 N/m, con ibu ing o i s imp o ed duc ili y.
In compa ison, ou s udy explo es he po en ial o ca bon ibe s (CFs) and ca bon
nano ubes (CNTs) as al e na i e ein o cemen s. Despi e using lowe ein o cemen dosages
han ypical SF-UHPC mix u es, he combined e ec o CFs (9 kg/m
3
) and CNTs (0.3% by
weigh o cemen ) esul ed in a 313% inc ease in ensile s eng h compa ed o he e e ence
mix. Fu he mo e, ac u e ene gy alues eached 291 N/m, placing ou sys em wi hin he
expec ed ange o s eel ibe - ein o ced UHPC. Unlike SF, ca bon-based ein o cemen s
also con ibu e o mic os uc u al densi ica ion, imp o ing bo h du abili y and esis ance
o mic oc acking.
O he ibe ypes [
14
], such as polyp opylene, polye hylene, and basal ibe s, ha e also
been in es iga ed in UHPC. While syn he ic ibe s imp o e i e esis ance, hey con ibu e
li le o comp essi e o ensile s eng h enhancemen s (a ound 120 MPa). Basal ibe s show
mode a e inc eases in mechanical pe o mance (o e 20% and 40% g ow h o comp essi e
and lexu al s eng h [
60
]) bu emain less e ec i e han SFs o CFs in s eng hening UHPC.
In ou s udy, he syne gy be ween CFs and CNTs p o ided an op imal balance be ween
ensile s eng h, ac u e esis ance, and wo kabili y, o e ing a p omising al e na i e o
adi ional SF-UHPC sys ems.
These indings sugges ha ca bon-based ein o cemen can se e as an e ec i e
al e na i e o s eel ibe s, pa icula ly in applica ions whe e high ensile pe o mance and
du abili y a e p io i ized o e maximum comp essi e s eng h. Fu u e esea ch should
u he explo e hyb id ibe sys ems, op imizing combina ions o CFs, CNTs, and o he
addi i es o achie e ailo ed mechanical p ope ies in UHPC.
Figu e 14 p esen s a ada cha e alua ing he pe o mance o UHPC mix u es ac oss
c i ical pa ame e s: wo kabili y, ac u e ene gy, po osi y, ensile s eng h, and comp essi e
s eng h. Each axis ep esen s a no malized alue o hese p ope ies, wi h he ou e mos
polygon (D9-0.54) demons a ing he mos balanced and supe io pe o mance. The cha
highligh s how inc easing CNT dosage enhances mechanical p ope ies and ac u e esis-
ance, albei wi h a g adual educ ion in wo kabili y. No ably, he D9-0.54 mix exhibi s he
la ges a ea, indica ing i s op imal o e all pe o mance.
Fibe s 2025,13, 49 17 o 20
Fibe s 2025, 13, x FOR PEER REVIEW 19 o 23
Figu e 14. Compa a i e pe o mance o UHPC mixes.
The D9-0.54 mix (9 kg/m
3
CFs + 0.54 w % CNTs) achie es he highes sco es in com-
p essi e s eng h (24% inc ease s. D9-0) and ensile s eng h (313% inc ease s. D0-0),
while main aining accep able wo kabili y (>28 cm slump). I s low po osi y (42% educ ion
s. D9-0) and high ac u e ene gy (291 N/m) unde sco e he syne gis ic effec o CFs and
CNTs in e ining he mic os uc u e and b idging c acks. This balance posi ions D9-0.54
as he op imal o mula ion o applica ions p io i izing s eng h, du abili y, and ac u e
esis ance.
5. Conclusions
• The non-co osi e na u e CFs and o CNTs make UHPC a iable and du able ma e-
ial o in as uc u e applica ions, pa icula ly in ha sh ma ine en i onmen s, whe e
long- e m pe o mance is c i ical.
• CFs alone achie ed a 32% educ ion in mac o-po osi y, while highe concen a ions
o CNTs (0.54 kg/m
3
) u he dec eased mac o-po osi y by up o 42%. This esul ed
in a dense conc e e ma ix, po en ially educing b i leness and inhibi ing c ack ini-
ia ion du ing ac u e. C i ically, he CNTs played a key ole in e ining he UHPC
mic os uc u e by illing nanoscale po es, dec easing po osi y, and enhancing ma ix
densi y, which con ibu es o imp o ed du abili y and esis ance o in e nal de ec s.
• The he mal analysis e ealed ha CNTs sligh ly delayed he ini ial mass loss ela ed
o mois u e and C–S–H dehyd a ion, a ibu ed o hei s eng hening o hyd a ion
p oduc s and o ma ion o dense C–S–H agglome a es. CNTs also inc eased he
mass loss om calcium hyd oxide decomposi ion, indica ing hei abili y o enhance
pozzolanic eac ions and C–S–H o ma ion.
• CFs play a c i ical ole in c ack ini ia ion and p opaga ion. They c ea e a b idging
effec ha modi ies po osi y and po e size dis ibu ion, enhancing ene gy abso p ion
du ing ac u e. CNTs also s eng hen he bond be ween agg ega es and he cemen
ma ix.
• The syne gis ic in eg a ion o CFs and CNTs signi ican ly enhanced UHPC’s mechan-
ical pe o mance—comp essi e s eng h inc eased up o 39% and ensile s eng h up
Figu e 14. Compa a i e pe o mance o UHPC mixes.
The D9-0.54 mix (9 kg/m
3
CFs + 0.54 w % CNTs) achie es he highes sco es in
comp essi e s eng h (24% inc ease s. D9-0) and ensile s eng h (313% inc ease s. D0-0),
while main aining accep able wo kabili y (>28 cm slump). I s low po osi y (42% educ ion
s. D9-0) and high ac u e ene gy (291 N/m) unde sco e he syne gis ic e ec o CFs
and CNTs in e ining he mic os uc u e and b idging c acks. This balance posi ions
D9-0.54 as he op imal o mula ion o applica ions p io i izing s eng h, du abili y, and
ac u e esis ance.
5. Conclusions
•
The non-co osi e na u e CFs and o CNTs make UHPC a iable and du able ma e ial
o in as uc u e applica ions, pa icula ly in ha sh ma ine en i onmen s, whe e
long- e m pe o mance is c i ical.
•
CFs alone achie ed a 32% educ ion in mac o-po osi y, while highe concen a ions
o CNTs (0.54 kg/m
3
) u he dec eased mac o-po osi y by up o 42%. This esul ed
in a dense conc e e ma ix, po en ially educing b i leness and inhibi ing c ack
ini ia ion du ing ac u e. C i ically, he CNTs played a key ole in e ining he UHPC
mic os uc u e by illing nanoscale po es, dec easing po osi y, and enhancing ma ix
densi y, which con ibu es o imp o ed du abili y and esis ance o in e nal de ec s.
•
The he mal analysis e ealed ha CNTs sligh ly delayed he ini ial mass loss ela ed
o mois u e and C–S–H dehyd a ion, a ibu ed o hei s eng hening o hyd a ion
p oduc s and o ma ion o dense C–S–H agglome a es. CNTs also inc eased he
mass loss om calcium hyd oxide decomposi ion, indica ing hei abili y o enhance
pozzolanic eac ions and C–S–H o ma ion.
•
CFs play a c i ical ole in c ack ini ia ion and p opaga ion. They c ea e a b idging e ec
ha modi ies po osi y and po e size dis ibu ion, enhancing ene gy abso p ion du ing
ac u e. CNTs also s eng hen he bond be ween agg ega es and he cemen ma ix.
•
The syne gis ic in eg a ion o CFs and CNTs signi ican ly enhanced UHPC’s mechani-
cal pe o mance—comp essi e s eng h inc eased up o 39% and ensile s eng h up
Fibe s 2025,13, 49 18 o 20
o 313% a he highes dosage. F ac u e ene gy also imp o ed wi h op imized CF
(9 kg/m3) and CNT (0.32 kg/m3) combina ions.
Fu u e esea ch should ocus on op imizing CNT dispe sion echniques, e alua ing
he long- e m du abili y o CF- and CNT- ein o ced UHPC unde eal-wo ld condi ions,
and explo ing he use o ecycled ca bon ibe s and sus ainable CNT p oduc ion me hods.
Addi ionally, he in e ac ion be ween CFs, CNTs, and o he nanoma e ials (e.g., g aphene
oxide o nano-silica) could be in es iga ed o de elop nex -gene a ion UHPC wi h en-
hanced pe o mance. La ge-scale s uc u al es ing and ield applica ions a e also essen ial
o alida e he p ac ical easibili y and economic iabili y o his ma e ial in eal-wo ld
cons uc ion p ojec s.
Au ho Con ibu ions: Concep ualiza ion, C.L. and H.C.; me hodology, J.D.R.; alida ion, J.D.R.;
o mal analysis, J.D.R.M.; in es iga ion, J.D.R.M.; da a cu a ion, J.D.R.M.; w i ing—o iginal d a
p epa a ion, J.D.R.M.; w i ing— e iew and edi ing, H.C.; isualiza ion, J.D.R.; supe ision, C.L.;
p ojec adminis a ion, H.C.; unding acquisi ion, H.C. All au ho s ha e ead and ag eed o he
published e sion o he manusc ip .
Funding: This esea ch was unded by he “Minis e io de Ciencia e Inno ación” o Spain unde
p ojec numbe s PID2019-110928RB-C33 and PID2023-147971OB-C32.
Da a A ailabili y S a emen : The o iginal con ibu ions p esen ed in he s udy a e included in he
a icle; u he inqui ies can be di ec ed o he co esponding au ho .
Acknowledgmen s: The au ho s would like o hank Come Technologies Canada Inco po a ed o
p o iding he academic license o D agon ly so wa e.
Con lic s o In e es : The au ho s decla e no con lic s o in e es .
Re e ences
1.
Huang, H.; Teng, L.; Khaya , K.H.; Gao, X.; Wang, F.; Liu, Z. Fo he Imp o emen o Mechanical and Mic os uc u al P ope ies
o UHPC wi h Fibe Alignmen Using Ca bon Nano ube and G aphi e Nanopla ele . Cem. Conc . Compos. 2022,129, 104462.
[C ossRe ]
2.
Bajabe , M.A.; Hakeem, I.Y. UHPC E olu ion, De elopmen , and U iliza ion in Cons uc ion: A Re iew. J. Ma e . Res. Technol.
2021,10, 1058–1074. [C ossRe ]
3.
Wang, Y.; Qiao, P.; Sun, J.; Chen, A. In luence o Fibe s on Tensile Beha io o Ul a-High Pe o mance Conc e e: A Re iew. Cons .
Build. Ma e . 2024,430, 136432. [C ossRe ]
4.
Akhnoukh, A.K.; Buckhal e , C. Ul a-High-Pe o mance Conc e e: Cons i uen s, Mechanical P ope ies, Applica ions and
Cu en Challenges. Case S ud. Cons . Ma e . 2021,15, e00559. [C ossRe ]
5.
de La a d, F.; Sed an, T. Op imiza ion o Ul a-High-Pe o mance Conc e e by he Use o a Packing Model. Cem. Conc . Res. 1994,
24, 997–1009. [C ossRe ]
6.
Bul e, H.C.; Jiménez, J.R.; Concha, A.M. de la Es udio Del Compo amien o de Ho migones de Muy Al a Resis encia Some idos a
Ca gas de Choque Té mico. Ho mig. Ace o 2022,73, 73–79. [C ossRe ]
7.
Am an, M.; Huang, S.S.; Onaizi, A.M.; Makul, N.; Abdelgade , H.S.; Ozbakkaloglu, T. Recen T ends in Ul a-High Pe o mance
Conc e e (UHPC): Cu en S a us, Challenges, and Fu u e P ospec s. Cons . Build. Ma e . 2022,352, 129029. [C ossRe ]
8.
Ríos, J.D.; Lei a, C.; A iza, M.P.; Sei l, S.; Ci uen es, H. Analysis o he Tensile F ac u e P ope ies o Ul a-High-S eng h
Fibe -Rein o ced Conc e e wi h Di e en Types o S eel Fibe s by X-Ray Tomog aphy. Ma e . Des. 2019,165, 107582. [C ossRe ]
9.
Imam, A.; Sha ma, K.K.; Kuma , V.; Singh, N. A Re iew S udy on Sus ainable De elopmen o Ul a High-Pe o mance Conc e e.
AIMS Ma e . Sci. 2022,9, 9–35. [C ossRe ]
10.
Muñoz-Espinoza, A.L.; López-Yépez, L.G.; Valdez-Aguila , J.A.; Jua ez-Al a ado, C.A.; Du án-He e a, A. Vi i ied Clay o he
P oduc ion o a G een Sus ainable Ul a-High-Pe o mance Fibe -Rein o ced Conc e e. Ma e ials 2024,17, 5624. [C ossRe ]
11.
Yoo, D.Y.; Ban hia, N.; Yoon, Y.S. Recen De elopmen o Inno a i e S eel Fibe s o Ul a-High-Pe o mance Conc e e (UHPC): A
C i ical Re iew. Cem. Conc . Compos. 2024,145, 105359. [C ossRe ]
12.
He, J.; Chen, W.; Zhang, B.; Yu, J.; Liu, H. The Mechanical P ope ies and Damage E olu ion o UHPC Rein o ced wi h Glass
Fibe s and High-Pe o mance Polyp opylene Fibe s. Ma e ials 2021,14, 2455. [C ossRe ] [PubMed]
Fibe s 2025,13, 49 19 o 20
13.
Chen, Z.; Fan, H.; Zheng, W.; Zhang, S.; Wu, X.; Fu, T.; Yu, D. In luence o Modi ied PVA Fibe on Ul a-High Pe o mance
Conc e e and I s Enhancing Mechanism. Polyme s 2024,16, 3449. [C ossRe ]
14.
Gong, J.; Ma, Y.; Fu, J.; Hu, J.; Ouyang, X.; Zhang, Z.; Wang, H. U iliza ion o Fibe s in Ul a-High Pe o mance Conc e e: A
Re iew. Compos. B Eng. 2022,241, 109995. [C ossRe ]
15.
Paj ˛ak, M.; Ponikiewski, T. Flexu al Beha io o Sel -Compac ing Conc e e Rein o ced wi h Di e en Types o S eel Fibe s. Cons .
Build. Ma e . 2013,47, 397–408. [C ossRe ]
16.
Yoo, D.Y.; Kim, S.W.; Pa k, J.J. Compa a i e Flexu al Beha io o Ul a-High-Pe o mance Conc e e Rein o ced wi h Hyb id
S aigh S eel Fibe s. Cons . Build. Ma e . 2017,132, 219–229. [C ossRe ]
17.
Pa chen, A.; Young, S.; Penumadu, D. An In es iga ion o Mechanical P ope ies o Recycled Ca bon Fibe Rein o ced Ul a-
High-Pe o mance Conc e e. Ma e ials 2023,16, 314. [C ossRe ]
18.
Xu, S.; Yang, Y.; Wu, C.; Liu, K. Elec omagne ic Wa e Abso p ion Pe o mance o UHPC Inco po a ed wi h Ca bon Black and
Ca bon Fibe . A ch. Ci . Mech. Eng. 2022,22, 71. [C ossRe ]
19.
Sun, C.S.; Fa zana, N.; Ku uppua achchi, D.; Azimi, M.; Zhong, H. Expe imen al and Analy ical S udies o an Ul a-High
Pe o mance Conc e e Beam Using Ca bon Fibe Rein o ced Polyme Ba s. Recen P og. Ma e . 2023,5, 19. [C ossRe ]
20.
Wang, X.Q.; Chow, C.L.; Lau, D. Mul iscale Pe spec i es o Ad ancing Sus ainabili y in Fibe Rein o ced Ul a-High Pe o mance
Conc e e. Ma e . Sus ain. 2024,2, 13. [C ossRe ]
21.
Huang, H.; Peng, C.; Luo, J.; Sun, T.; Deng, T.; Hu, J.; He, Z.; Wei, J.; Yu, Q.; An a o na, K.G.; e al. Mic omechanical P ope ies o
In e acial T ansi ion Zone be ween Ca bon Fibe s and UHPC Ma ix Based on Nano-Sc a ching Tes s. Cem. Conc . Compos. 2023,
139, 105014. [C ossRe ]
22.
Shila , F.A.; Ganacha i, S.V.; Pa il, V.B. Ad ancemen o Nano-Based Cons uc ion Ma e ials-A Re iew. Cons . Build. Ma e . 2022,
359, 129535. [C ossRe ]
23.
Suji ha, V.S.; Ramesh, B.; Xa ie , J.R. E ec s o Nanoma e ials on Mechanical P ope ies in Cemen i ious Cons uc ion Ma e ials
o High-S eng h Conc e e Applica ions: A Re iew. J. Adhes. Sci. Technol. 2024,38, 3737–3768. [C ossRe ]
24.
Ruiz Ma inez, J.D.; Ci uen es, H.; Rios, J.D.; A iza, P.; Lei a, C. De elopmen o Mo a s Tha Use Recycled Agg ega es om a
Sodium Silica e P ocess and he In luence o G aphene Oxide as a Nano-Addi ion. Ma e ials 2023,16, 7167. [C ossRe ]
25.
Ríos, J.D.; Vahí, A.; Lei a, C.; la Concha, A.; Ci uen es, H. Analysis o he U iliza ion o Ai -Cooled Blas Fu nace Slag as Indus ial
Was e Agg ega es in Sel -Compac ing Conc e e. Sus ainabili y 2019,11, 1702. [C ossRe ]
26.
Yoo, D.Y.; Oh, T.; Ban hia, N. Nanoma e ials in Ul a-High-Pe o mance Conc e e (UHPC)—A Re iew. Cem. Conc . Compos. 2022,
134, 104730. [C ossRe ]
27.
Wu, Z.; Shi, C.; Khaya , K.H.; Wan, S. E ec s o Di e en Nanoma e ials on Ha dening and Pe o mance o Ul a-High S eng h
Conc e e (UHSC). Cem. Conc . Compos. 2016,70, 24–34. [C ossRe ]
28.
Jung, M.; Pa k, J.; Hong, S.-g.; Moon, J. Elec ically Cu ed Ul a-High Pe o mance Conc e e (UHPC) Embedded wi h Ca bon
Nano ubes o Field Cas ing and C ack Sensing. Ma e . Des. 2020,196, 109127. [C ossRe ]
29.
Jung, M.; Pa k, J.-s.; Hong, S.G.; Moon, J. Mic o- and Meso-S uc u al Changes on Elec ically Cu ed Ul a-High Pe o mance
Fibe -Rein o ced Conc e e wi h Dispe sed Ca bon Nano ubes. Cem. Conc . Res. 2020,137, 106214. [C ossRe ]
30.
Chen, Z.; Lim, J.L.G.; Yang, E.H. Ul a High Pe o mance Cemen -Based Composi es Inco po a ing Low Dosage o Plasma
Syn hesized Ca bon Nano ubes. Ma e . Des. 2016,108, 479–487. [C ossRe ]
31.
Shah, A.; Chaudha y, M.; Sh es ha, J.K. Pa e n o Co neal Diseases in Paedia ic Age G oup a a Te ia y Eye Ca e Cen e in
Nepal. Nepal. J. Oph halmol. 2017,9, 37–42. [C ossRe ] [PubMed]
32.
Viana, T.M.; Bacela , B.A.; Coelho, I.D.; Lud ig, P.; San os, W.J. Beha iou o Ul a-High Pe o mance Conc e es Inco po a ing
Ca bon Nano ubes unde The mal Load. Cons . Build. Ma e . 2020,263, 120556. [C ossRe ]
33.
Zhang, W.; Zeng, W.; Zhang, Y.; Yang, F.; Wu, P.; Xu, G.; Gao, Y. In es iga ing he In luence o Mul i-Walled Ca bon Nano ubes
on he Mechanical and Damping P ope ies o Ul a-High Pe o mance Conc e e. Sci. Eng. Compos. Ma e . 2020,27, 433–444.
[C ossRe ]
34.
Jung, M.; Hong, S.-g.; Moon, J. Ozone T ea men on he Dispe sion o Ca bon Nano ubes in Ul a-High Pe o mance Conc e e.
Ma e . Des. 2020,193, 108813. [C ossRe ]
35.
Ruan, Y.; Han, B.; Yu, X.; Zhang, W.; Wang, D. Ca bon Nano ubes Rein o ced Reac i e Powde Conc e e. Compos. Pa A Appl. Sci.
Manu . 2018,112, 371–382. [C ossRe ]
36.
Wang, J.; Dong, S.; Pang, S.D.; Yu, X.; Han, B.; Ou, J. Tailo ing An i-Impac P ope ies o Ul a-High Pe o mance Conc e e by
Inco po a ing Func ionalized Ca bon Nano ubes. Enginee ing 2022,18, 232–245. [C ossRe ]
37.
Ríos, J.D.; Ci uen es, H.; Ruiz, G.; González, D.C.; Vicen e, M.A.; Yu, R.C.; Lei a, C. Mul iscale Analysis o Ca bon Mic o ibe
Rein o cemen on F ac u e Beha io o Ul a-High-Pe o mance Conc e e. Eng. F ac . Mech. 2025,319, 110998. [C ossRe ]
38.
Ríos, J.D.; Lei a, C.; de la Concha, A.; A iza, M.P.; Ci uen es, H. In luence o G aphene Oxide Concen a ion and Ul asonica ion
Ene gy on F ac u e Beha io o Nano-Rein o ced Cemen Pas es. C ys als 2024,14, 707. [C ossRe ]
39.
EN 12350-2; Tes ing F esh Conc e e—Pa 2: Slump Tes . Eu opean Commi ee o S anda diza ion (CEN): B ussels,
Belgium, 2020
.
Fibe s 2025,13, 49 20 o 20
40.
Nguyen Amanjean, E.; Mou e , M.; Vidal, T. E ec o Design Pa ame e s on he P ope ies o Ul a-High Pe o mance Fib e-
Rein o ced Conc e e in he F esh S a e. Cons . Build. Ma e . 2019,224, 1007–1017. [C ossRe ]
41.
Ríos, J.D.; Ci uen es, H.; Lei a, C.; Sei l, S. Analysis o he Mechanical and F ac u e Beha io o Hea ed Ul a-High-Pe o mance
Fibe -Rein o ced Conc e e by X-Ray Compu ed Tomog aphy. Cem. Conc . Res. 2019,119, 77–88. [C ossRe ]
42.
EN-12390-3; Tes ing Ha dened Conc e e—Pa 3: Comp essi e S eng h o Tes Specimens. Eu opean Commi ee o S anda diza-
ion (CEN): B ussels, Belgium, 2020.
43.
RILEM TCM-85. De e mina ion o he F ac u e Ene gy o Mo a and Conc e e by Means o Th ee-Poin Bend Tes s on No ched
Beams. Ma e . S uc . 1985,18, 287–290. [C ossRe ]
44.
Abdalla, H.M.; Ka ihaloo, B.L. A Me hod o Cons uc ing he Bilinea Tension So ening Diag am o Conc e e Co esponding o
I s T ue F ac u e Ene gy. Mag. Conc . Res. 2004,56, 597–604. [C ossRe ]
45.
Ramachand a Mu hy, A.; Ka ihaloo, B.L.; Iye , N.R.; Raghu P asad, B.K. Bilinea Tension So ening Diag ams o Conc e e Mixes
Co esponding o Thei Size-Independen Speci ic F ac u e Ene gy. Cons . Build. Ma e . 2013,47, 1160–1166. [C ossRe ]
46.
Villain, G.; Thie y, M.; Pla e , G. Measu emen Me hods o Ca bona ion P o iles in Conc e e: The mog a ime y, Chemical
Analysis and Gammadensime y. Cem. Conc . Compos. 2007,37, 1182–1192. [C ossRe ]
47.
Liang, X.; Li, M.; Wang, L.; Liu, S. E ec o Mic owa e P e ea men on he P ope ies and Mic os uc u e o Low-Concen a ion
Ca bon Dioxide Ea ly Cu ed Cemen -Based Ma e ials. Buildings 2024,14, 1074. [C ossRe ]
48.
Fu, Q.; Zhou, Z.; Wang, Z.; Huang, J.; Niu, D. Insigh in o Dynamic Comp essi e Response o Ca bon Nano ube/Ca bon
Fibe -Rein o ced Conc e e. Cem. Conc . Compos. 2022,129, 104471. [C ossRe ]
49.
Xu, S.; Wang, J.; Ma, Q.; Wang, L.; Zhang, T. E ec and Mechanism o Two Di e en Types o Wa e p oo Admix u es and
Silica Fume on he Hyd a ion and Mechanical P ope ies o Na u al Hyd aulic Lime. Case S ud. Cons . Ma e . 2023,18, e01925.
[C ossRe ]
50.
Ci uen es, H.; Lei a, C.; Medina, F.; Fe nández-Pe ei a, C. E ec s o Fib es and Rice Husk Ash on P ope ies o Hea ed HSC. Mag.
Conc . Res. 2012,64, 457–470. [C ossRe ]
51.
Ponikiewski, T.; Ka ze , J.; Bugdol, M.; Rudzki, M. De e mina ion o 3D Po osi y in S eel Fib e Rein o ced SCC Beams Using
X-Ray Compu ed Tomog aphy. Cons . Build. Ma e . 2014,68, 333–340. [C ossRe ]
52.
Zeng, J.J.; Hao, Z.H.; Sun, H.Q.; Zeng, W.B.; Fan, T.H.; Zhuge, Y. Du abili y Assessmen o Ul a-High-Pe o mance Conc e e
(UHPC) and FRP G id-Rein o ced UHPC Pla es unde Ma ine En i onmen s. Eng. S uc . 2025,323, 119313. [C ossRe ]
53.
Shah, S.P.; Swa z, S.E.; Ouyang, C. F ac u e Mechanics o Conc e e: Applica ions o F ac u e Mechanics o Conc e e, Rock and O he
Quasi-B i le Ma e ials; John Wiley & Sons: Hoboken, NJ, USA, 1995; ISBN 0471303119.
54.
Ríos, J.D.; Ci uen es, H.; Lei a, C.; Ga cía, C.; Alba, M.D. Beha io o High-S eng h Polyp opylene Fibe -Rein o ced Sel -
Compac ing Conc e e Exposed o High Tempe a u es. J. Ma e . Ci . Eng. 2018,30, 04018271. [C ossRe ]
55.
Alyhya, W.S.; Abo Dhahee , M.S.; Al-Rubaye, M.M.; Ka ihaloo, B.L. In luence o Mix Composi ion and S eng h on he F ac u e
P ope ies o Sel -Compac ing Conc e e. Cons . Build. Ma e . 2016,110, 312–322. [C ossRe ]
56.
Bowe , A.F.; O iz, M. The In luence o G ain Size on he Toughness o Monoli hic Ce amics. J. Eng. Ma e . Technol. 1993,115,
228–236. [C ossRe ]
57.
Ruiz Ma ínez, J.D.; Ríos, J.D.; Pé ez-So iano, E.M.; Ci uen es, H.; Lei a, C. Enhancing he Ma ix-Fibe Bond in Ul a-High-
Pe o mance Fibe -Rein o ced Conc e e Using a High Pe o mance Plas icize . Impac on he Flowabili y, Physical and Mechanical
P ope ies. Cons . Build. Ma e . 2025,470, 140683. [C ossRe ]
58.
Yoo, D.Y.; Shin, W.; Chun, B.; Ban hia, N. Assessmen o S eel Fibe Co osion in Sel -Healed Ul a-High-Pe o mance Fibe -
Rein o ced Conc e e and I s E ec on Tensile Pe o mance. Cem. Conc . Res. 2020,133, 106091. [C ossRe ]
59.
Du, J.; Meng, W.; Khaya , K.H.; Bao, Y.; Guo, P.; Lyu, Z.; Abu-obeidah, A.; Nassi , H.; Wang, H. New De elopmen o Ul a-High-
Pe o mance Conc e e (UHPC). Compos. B Eng. 2021,224, 109220. [C ossRe ]
60.
Chen, Z.; Wang, X.; Ding, L.; Jiang, K.; Su, C.; Liu, J.; Wu, Z. Mechanical P ope ies o a No el UHPC Rein o ced wi h Mac o
Basal Fibe s. Cons . Build. Ma e . 2023,377, 131107. [C ossRe ]
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