Conc e e a ches and ein o ced soil: a sus ainable al e na i e
s uc u e o oad b idges
A ches en bé on e sol en o cé: une s uc u e al e na i e du able aux pon s
ou ie s
K. Malekmohammadi*, A. Moncada
Depa men o Ci il and En i onmen al Enginee ing, Uni e si a Poli ècnica de Ca alunya·Ba celonaTech
(UPC) / In e na ional Cen e o Nume ical Me hods in Enginee ing (CIMNE), Ba celona, Spain
I.P. Damians
In e na ional Cen e o Nume ical Me hods in Enginee ing (CIMNE), Uni e si a Poli ècnica de
Ca alunya·Ba celonaTech (UPC) / VSL In e na ional, Ba celona, Spain
*khashaya [email protected]
ABSTRACT: Road b idges a e necessa y in as uc u es o anspo a ion. As such, hey a e subjec o ho ough sc u iny
o hei en i onmen al, social, and economic impac s. An adequa e subs an iali y assessmen applied o b idge design mus
minimize he nega i e impac s o he s uc u e on he su ounding en i onmen . A conc e e deck and piles, oge he wi h
can ile e abu men s, is a well-es ablished and con en ional b idge design op ion. An al e na i e solu ion is p ecas conc e e
a ches, widely used in b idge and unnel cons uc ions, p o iding s able, long-las ing suppo e en unde hea y load
condi ions. Conc e e a ches can be cons uc ed oge he wi h ein o ced soil walls (RSW) solu ions, o bo h embankmen
and abu men zones, which a e conside ed cos -e ec i e solu ions wi h sho cons uc ion pe iods, making hem an a ac i e
op ion o such s uc u al and geo echnical enginee ing p ojec s. The compound conc e e a ch and RSW s uc u e esul s in
a esilien , e icien , and cos -e ec i e design. This s udy p esen s a simple app oach o an en i onmen al and economic
assessmen o wo b idge designs: a classical solu ion wi h can ile e abu men s and a conc e e deck slab, and conc e e
a ches wi h RSW on op. Based on he en i onmen al impac , and associa ed cos s, he p ecas a ch b idges wi h RSW
solu ion a e judged o be he be e al e na i e.
RÉSUMÉ: Les pon s ou ie s son une in as uc u e nécessai e au anspo . À ce i e, ils on l’obje d’un examen
minu ieux quan à leu s impac s en i onnemen aux, sociaux e économiques. Une é alua ion adéqua e du ca ac è e
subs an iel appliquée à la concep ion du pon doi minimise les impac s néga i s de la s uc u e su l’en i onnemen
en i onnan . Un ablie e des pieux en bé on, ainsi que des culées en po e-à- aux, cons i uen une concep ion de pon bien
é ablie. Une solu ion al e na i e consis e en des a ches en bé on p é ab iqué, la gemen u ilisées dans la cons uc ion de
pon s e de unnels, o an un suppo s able e du able, même dans des condi ions de cha ge lou de. Les a ches en bé on
peu en ê e cons ui es a ec des solu ions de mu s en sol en o cé (RSW), an pou les zones de emblai que de culées, qui
son considé ées comme des solu ions en ables a ec des pé iodes de cons uc ion cou es, ce qui en ai une op ion a ayan e
pou de els p oje s d'ingénie ie s uc u elle e géo echnique. L'a che en bé on composée e la s uc u e RSW donnen lieu à
une concep ion ésilien e, e icace e en able. Ce e é ude p ésen e une app oche simple pou une é alua ion
en i onnemen ale e économique de deux modèles de pon : une solu ion classique a ec des culées en po e-à- aux e une
dalle de ablie en bé on, e des a ches en bé on a ec un RSW. Su la base de l'impac en i onnemen al e des coû s associés,
les pon s en a c p é ab iqués a ec la solu ion RSW son considé és comme la meilleu e al e na i e.
Keywo ds: Geosyn he ic ein o cemen ; p ecas a ch b idges; ein o ced soil walls; sus ainabili y assessmen .
1 INTRODUCTION
Ci il enginee ing wo ks encompass a wide ange o
s uc u es, including, bu no limi ed o, buildings,
pa emen s, b idges, ounda ions, and ein o ced soil
s uc u es. The inclusion o sus ainabili y c i e ia in he
decision-making p ocess o ci il enginee ing design,
including geo echnical enginee ing p ojec s, is
becoming p e alen (Aguado e al., 2012; MacAskill
and Gu h ie, 2013, Basu e al., 2014). Sus ainabili y
encompasses he ul illmen o h ee dis inc se s o
c i e ia ega ding en i onmen al, economic, and
socie al/ unc ional aspec s (A no G oup, 2012; ISO,
2006). B idges made o conc e e a ches wi h
ein o ced soil walls (RSW) a e used o pedes ians,
oad, and ail a ics. The complexi y o conc e e a ch
P oceedings o he XVIII ECSMGE 2024
GEOTECHNICAL ENGINEERING CHALLENGES
TO MEET CURRENT AND EMERGING NEEDS OF SOCIETY
© 2024 he Au ho s
ISBN 978-1-032-54816-6
DOI 10.1201/9781003431749-
Open Access: www. aylo ancis.com, CC BY-NC-ND 4.0 license
102
647
P oceedings o he XVIII ECSMGE 2024
A – New de elopmen s on s uc u al design
and ein o ced soil b idge sys ems esides in he p ope
assessmen o soil-s uc u e in e ac ion, he impac o
la e al soil p essu e, and he bounda y condi ion a he
base o he b idge suppo s. This s udy p esen s a
simpli ied and educed app oach and esul s o
e alua e and compa e he en i onmen al and economic
aspec s o a sus ainabili y assessmen o wo b idge
designs composed o (i) can ile e abu men s and
conc e e deck slab, and (ii) p ecas conc e e a ches and
back- o-back ein o ced soil wall
embankmen /abu men . The assessmen o
en i onmen al ac o s is conduc ed u ilizing a educed
Li e Cycle Assessmen (LCA) me hodology (e.g.,
Damians e al., 2016). Ideally, a LCA should
comp ehensi ely e alua e all po en ial en i onmen al
implica ions associa ed wi h he cons uc ion p ocess
and ma e ials employed in p ojec ac i i ies.
2 CASE STUDY AND METHODOLOGY
Figu e 1 shows a schema ic ep esen a ion o he wo
ypes o oad b idges included in his s udy.
Dimensions we e de e mined h ough con en ional
design me hods. To p ope ly e alua e he
en i onmen al impac ac oss bo h al e na i e
solu ions, a Func ional Uni (FU) mus be de ined. In
his pa icula scena io, he compa a i e FU is de ined
as a b idge wi h a wid h o 12 me e s and a span o 10
me e s, designed o accommoda e a wo-lane ci ilian
oadway wi h a dis ibu ed a ic su cha ge load o 10
kPa, o e a design li e o 100 yea s. In his s udy, i is
assumed ha bo h al e na i es a e ins alled on a
compe en /s i ounda ion and does no ake in o
accoun he en i onmen al and economic implica ions
o si e p epa a ion and inal g ading (i.e., ounda ion
p epa a ion), as hese impac s a e expec ed o be
compa able be ween he wo ypes o s uc u es. In he
same way, he scope o his s udy is es ic ed o he
b idge span S (see Figu e 1). The analysis o he
Can ile e +deck b idge does no ake in o accoun he
ma e ial/ illing loca ed behind he can ile e
abu men s. Likewise, he A ch+RSW solu ion does no
conside he RSW beyond he leng h S (see he limi o
he s udy de ailed zone in Figu e 1). Fo he
A ch+RSW b idge design, he back- o-back ein o ced
soil s uc u e uses polyme ic s ap ein o cemen and
p ecas ein o ced conc e e panels.
The li e-cycle s ages encompass he en i e p ocess
om he ex ac ion o aw ma e ials om he na u al
en i onmen . In e media e s ages include ma e ial
p ocessing o c ea e he necessa y componen s,
anspo a ion o ma e ials/componen s, ins alla ion
wo k, e c.
B idge deck slab
S = 10 m
H = 10 m
6 m
9.2 m
1.2 m
Limi o
he s udy
0.8 m
Can ile e
1 m
(a) Geome y o Can ile e +deck.
(b) Geome y o A ch+RSW.
Figu e 1. Schema ic geome y o (a) Can ile e +deck
and (b) A ch+RSW.
H = 10 m
6.6 m
0.25 m
Rein o ced soil
S = 10 m
Panels
(RSW acing)
Limi o
he s udy
0.6 m
0.6 m
Table 1 shows he en i onmen al in en o y
pe aining o he ma e ials and cons uc ion- ela ed
ac i i ies included in he p esen in es iga ion. The
deck b idge and can ile e abu men al e na i e
equi es conside ably mo e conc e e and ein o cing
s eel (i.e., eba ) compa ed o he a ch b idge segmen s
and back- o-back RSW solu ion. The main s uc u al
componen o he con en ional b idge is he ein o ced
conc e e, while ha o he a ch b idge is he ein o ced
soil (i.e., back ill and polyme ic s ap ein o cemen s).
Back ill ma e ial is assumed o be b ough om a
dis ance o 10 km. The can ile e +deck b idge
includes on-si e conc e e pou ing. The expec ed
dis ance o he anspo a ion o p ecas conc e e
panels and p ecas conc e e a ches om he
manu ac u ing si e was 10 km. In addi ion, he
anspo a ion dis ances o conc e e mix ucks, s eel
eba , and polyme ic ein o cemen s aps we e
assumed o be 10 km because o conside a ion o he
same dis ance/condi ion o anspo a ion o all
solu ions.
Li e cycle assessmen s (LCA) we e ca ied ou
using SimaP o 9.4.0.2 so wa e (PRé Consul an s
B.V., 2010). Inpu alues o ma e ial and ene gy usage
we e ob ained using he Ecoin en 3.8 da abase
(Ecoin en Cen e, 2014) and ReCiPe 2016 me hod
1.1 (Huijb eg s e al., 2017), all a ailable wi hin
SimaP o. The economic analysis was conduc ed o
648 P oceedings o he XVIII ECSMGE 2024
Conc e e a ches and ein o ced soil: a sus ainable al e na i e s uc u e o oad b idges
bo h solu ions using he ITeC BEDEC cos da abase.
The en i onmen al impac is assessed using only wo
midpoin indica o s: he Global Wa ming Po en ial
(GWP), which measu es he impac o ca bon dioxide
equi alen (amoun o CO2 eq.) emissions on he
a mosphe e, and he Cumula i e Ene gy Demand
(CED), employed o he assessmen o ene gy
consump ion (in Joules). Bo h en i onmen al
indica o s a e analyzed ac oss he whole li e cycle o
he main in ol ed ma e ials, p oduc s, p ocesses,
and/o cons uc ion- ela ed ac i i ies in bo h p oposed
b idge cons uc ion al e na i es.
3 ENVIRONMENTAL AND ECONOMIC
ASSESSMENT
Figu e 2 shows he o al GWP (2a) emissions and CED
(2b) o bo h al e na i es. As an icipa ed, he adi ional
solu ion (Can ile e +deck) esul s in he highes
emissions o CO2 eq. and ene gy consump ion. GWP
and CED alues o he A ch+RSW s uc u e we e
ound o be abou 85% and 82% lowe han hose o
he Can ile e +deck design, espec i ely. This is
explained by he high ene gy equi emen s in he
p oduc ion o s eel and conc e e, which se e as he
main s uc u al componen s o he con en ional b idge
case. Combined con ibu ions o conc e e and s eel
componen s a e he mos signi ican ac o s in he
o e all en i onmen al impac o bo h cases, accoun ing
o 58% and 37% o o al CO2 eq. and 46.2% and 45%
o CED alues, o he con en ional and a ch solu ions,
espec i ely. Compa ed o conc e e and s eel,
cons uc ion ac i i ies and ma e ial anspo a ion
con ibu e a small po ion o o al CO2 eq. and GJ
alues. Fu he mo e, acco ding o he ou comes o he
economic analysis, A ch+RSW solu ion led o abou
47% educ ion in cons uc ion cos s wi h espec o he
con en ional b idge s uc u e (Figu e 3). In his
solu ion, he RSW s uc u e con ibu es mos o he
cons uc ion cos s, a 56.7%, because mo e
componen s need o be used o cons uc ion.
Table 1. En i onmen al in en o y including ma e ials, cons uc ion ac i i ies and anspo a ion de ails.
Case
Ca ego y
I ems
Uni
Value
Can ile e +deck
S uc u al ma e ial
Conc e e
m3
501.6
Rein o cing s eel ( eba )
39.3
Cons uc ion
Pou ing conc e e
h
16.72
Rein o cing ( eba ) ixing
h
263.3
Fo mwo k ins alla ion
h
796
T anspo a ion
Conc e e, ein o cing s eel, e c.
km
10
A ch+RSW
S uc u al ma e ial
Conc e e ( oo ing)
m3
8.4
P ecas a ches
m3
55.32
P ecas panels
m2
100.2
Polyme ic s ap
kg
288
Cons uc ion
Rein o ced back ill
m3
601.2
Panel ins alla ion
h
44.5
Ea h wo k (back illing and compac ing)
h
22.5
T anspo a ion
Conc e e, p ecas a ches/panels, ein s., e c.
km
10
Back ill ma e ial
km
10
(a) To al GWP o bo h b idges.
(b) To al CED o bo h b idges.
Figu e 2. To al (a) GWP, (b) CED o cons uc ion o bo h b idge solu ions.
Can ile e +deck A ch+RSW
0
50
100
150
200
250
Type o S uc u e
Global wa ming po en ial: CO2 eq
S (14.4%)
Co (51.4%)
Co (60%)
Ps (4.1%)
So (14.4%)
C (15.7%)
S
C (1%)
S (39%)
S – S eel eba
Co – Conc e e
C – Cons uc ion ac i i ies &
T anspo a ion
So – Soil
Ps – Polyme ic s ap
Can ile e +deck A ch+RSW
0
400
800
1200
1600
2000
Type o S uc u e
Cumula i e ene gy demand: GJ
C (22%)
C (1%)
Co (48%)
Co (35%)
S (51%) C – Cons uc ion ac i i ies &
T anspo a ion
Co – Conc e e
S – S eel eba
So – Soil
Ps – Polyme ic s ap
S (15%)
Ps (9%)
So (19%)
649
P oceedings o he XVIII ECSMGE 2024
A – New de elopmen s on s uc u al design
Can ile e +deck A ch+RSW
0
40000
80000
120000
160000
200000
Type o S uc u e
Cons uc ion cos ing: €
Ca (75.6%)
A (27.5%)
Rs (56.7%)
T (15.8%)
De (20.3%)
T (4.1%)
Ca – Can ile e
De – Deck
A – A ch
Rs – RSW
T – T anspo a ion
Figu e 3. Cons uc ion cos s o bo h b idge solu ions.
4 CONCLUSIONS
A simpli ied li e-cycle and economic assessmen o
Can ile e +deck and A ch+RSW b idge solu ions ha
sa is y he same unc ion we e pe o med, and some
esul s we e p esen ed. The p ima y indings o he
compa ison a e as ollows:
• A ch+RSW wi h ein o ced soil s uc u es
showed educed CO2 eq. emissions and ene gy
equi emen s compa ed o a con en ional
Can ile e +deck b idge design. A ch+RSW
solu ions esul ed in educ ions o abou 85%
and 82% o CO2 eq. emissions and CED,
espec i ely, wi h ega ds o he
Can ile e +deck design app oach.
• Reduced en i onmen al indica o s o he a ch
b idge al e na i e a e a ibu ed o he use o
compac ed soil and polyme ic ein o cemen s as
he p ima y s uc u al elemen s, as opposed o
conc e e and s eel in he con en ional solu ion.
• A ch+RSW b idges can esul in cons uc ion
cos educ ions o abou 50%.
This s udy was limi ed o he en i onmen al and
economic impac s o wo di e en b idge ypes:
can ile e abu men wi h b idge deck slab and
ein o ced soil walls o e p ecas a ches. Fo hcoming
esea ch equi es a comp ehensi e s udy o ull
sus ainabili y assessmen including en i onmen al,
economic, and socie al/ unc ional/ echnical aspec s
h ough mul i-c i e ia analysis and di e en
s akeholde scena ios. Fu he mo e, i is
ecommended o expand he scope o his s udy o
encompass a ious ypes o b idges, including
di e en dimensions and echnologies.
ACKNOWLEDGEMENTS
The au ho s wish o acknowledge he suppo ecei ed
om VSL Cons uc ion Sys ems (Spain) and Eng.
Vi omi Nikolic o his aluable da a on cons uc ion
me hods, GECO Indus ial (Ko ea, Rep. o ), he
Depa men o Ci il and En i onmen al Enginee ing
(DECA) o Uni e si a Poli ècnica de
Ca alunya·Ba celonaTech (UPC), and he
In e na ional Cen e o Nume ical Me hods in
Enginee ing (CIMNE).
REFERENCES
A no G oup (2012) CEN/TC 350: Sus ainabili y o
Cons uc ion Wo ks. A no G oup, Pa is, F ance. See
h p://po ailg oupe.a no . /public_espaceno malisa io
n/CENTC350/index.h ml (accessed: 05/08/2016).
Aguado, A., Caño, A. D., de la C uz, M. P., Gómez, D., and
Josa, A. (2012). Sus ainabili y assessmen o conc e e
s uc u es wi hin he Spanish s uc u al conc e e code. J.
o Cons . Eng. and Manag., 138(2), 268-276.
h ps://doi.o g/10.1061/(ASCE)CO.1943-
7862.0000419.
Basu, D., Mis a, A., and Puppala, AJ. (2014). Sus ainabili y
and geo echnical enginee ing: pe spec i es and e iew.
Can. Geo ech. J., 52(1): 96–113.
h ps://doi.o g/10.1139/cgj-2013-0120.
Damians, IP., Ba hu s , RJ., Ad ogue , E., Josa, A., and
Llo e , A. (2016).En i onmen al assessmen o ea h
e aining wall s uc u es. En i on. Geo ech.
h p://dx.doi.o g/10.1680/jenge.15.00040.
Ecoin en Cen e. (2014). Ecoin en da abase 3.1.
Ecoin en Cen e, Swiss Cen e o Li e Cycle
In en o ies, Zu ich, Swi ze land. See
h p://www.ecoin en .ch/ (accessed 02/02/2016).
Huijb eg s, M.A.J., S einmann, Z.J.N., Elshou , P.M.F., e
al. (2017). ReCiPe2016: a ha monised li e cycle impac
assessmen me hod a midpoin and endpoin le el. In J
Li e Cycle Assess, 22, 138–147.
h ps://doi.o g/10.1007/s11367-016-1246-y.
MacAskill, K., and Gu h ie, P. (2013). Risk-based
app oaches o sus ainabili y in ci il enginee ing. In
P oc. o he Ins . o Ci . Eng.-Eng. Sus ain. 166 (4) pp.
181-190. Thomas Tel o d L d.
h ps://doi.o g/10.1680/ensu.12.00001.
Ins i u e o Cons uc ion Technology o Ca alonia (ITeC
BEDEC). A aialble a :
h ps://me abase.i ec.ca / ide/es/bedec/i ec accesed:
10/09/2023.
ISO (In e na ional O ganiza ion o S anda diza ion)
(2006a) ISO 14040: En i onmen al managemen – li e
cycle assessmen – p inciples and amewo k. ISO,
Gene a, Swi ze land.
PRé Consul an s B.V. (2010) SimaP o so wa e, .8.0.2.
Ame s oo . U ech , Ne he lands. See
h p://www.p esus ainabili y.com (accessed
02/02/2016).
650 P oceedings o he XVIII ECSMGE 2024