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ACKNOWLEDGEMENT
A project is always a coordinated and scheduled team effort, but it can never reach
completion without proper guidence and encouragement.
Words are short for expressing our deepest and sincere thanks towards our project
guide S.D. P.V. MANE Bharati Vidya peeth Deemed Univerity C!""e#e !$
P%ne.
We are thankfull to the principal Dr. A.&. Bha"era! !$ Bharati Vidya peeth
Deemed Univerity C!""e#e !$ En#ineerin#' P%ne for graniting us a wonderful
opportunity.
We are also thankful to our principal Shri. S.V. Andhare ( )ead !$ the
Department Pr!$. *Mr.+ V.S. S!h!ni * )ead !$ Civi" Department+ for their
support that has being given to us in the form of Infrastructure and Facilities.
ast but not. We must thank all the other teaching and non!teaching staff of civil
department for their assistance.
S& NO. NAME
, PAWA& OMEA& -UL/KA&
0 TANWA& MO)D AWAD MO)D SAK/L
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EECT O CL/MATE ON CONC&ETE
Name12 PAWA& OMEA& -UL/KA&
Mem3erhip n!12 45656
C!%re12 T.En##. Civi" Part //
A/CTE /ntit%ti!n1
Bharati Vidyapeeth Deemed Univerity C!""e#e
En#ineerin#' P%ne 7 5,,859 *Maharahtra+
S& NO. NAME MEMBE&S)/P
NO.
COU&SE
, PAWA& OMEA&
-UL/KA&
45656 T.ENGG. C/V/L
PA&T //
A:ademi: ;ear 12 08,6208,<
DEPA&TMENT O C/V/L ENG/NEE&/NG
Bharati Vidyapeeth Deemed Univerity C!""e#e
En#ineerin#' P%ne 7 5,,859 *Maharahtra+
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EECT O CL/MATE ON CONC&ETE
A "roject submitted in partial fulfillment of
#.$ngg. %ivil "art II in A&I%$
'iploma in %ivil $ngineering
PAWA& OMEA& -UL/KA&
(y
Mem3erhip n!. 45656
(
TANWA& MO)D AWAD MO)D SAK/L
Mem3erhip n!. 45084
)nder the *uidance of
S.D. P.V. MANE
BVDUCOEP PUNE259
#he Institution of %ivil $ngineering +India
-/0!-/1
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A:ademi: ;ear 12 08,6208,<
DEPA&TMENT O C/V/L ENG/NEE&/NG
Bharati Vidyapeeth Deemed Univerity C!""e#e
En#ineerin#' P%ne 7 5,,859 *Maharahtra+
CE&T//CATE
#his is to certify that the "roject entitled 2 %omparative 3tudy 4f %onstruction
Work (etween ocal %ontractor And 5ualified %ontractor 6.
The m!di$ied =!r> d!ne %nder 3y #%idan:e in partia" $%"$i""ment !$ the
t%dent $!r the a=ard !$ T.En##. Civi" Part // in Civi" En#ineerin# $!r
A:ademi: ;ear 08,6208,
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EFFECT OF CLIMATE ON CONCRET
Reinforced concrete more liable to damage under
climate change
Concrete structures, such as buildings, bridges and
harbours, reinforced with internal metal bars for added
strength are an integral part of social and economic
activities in modern societies, with some infrastructures
built to last hundreds of years. However, it is thought that
higher atmospheric CO2 and rising temperatures
projected under a changing climate could increase the
rate of corrosion of the reinforcing metal resulting in
serious cracking of reinforced concrete structures.
Weakened infrastructure will cost more to repair and
disrupt the use of facilities in the future. his study
investigated climate change impacts on the risk of
corrosive damage to concrete structures over !"" years,
from 2""" to 2!"", by modelling changes in CO2
concentration, temperature and humidity in two
#ustralian cities$ %ydney &representative of a temperate
climate' and (arwin &representative of a tropical climate'.
hree scenarios were compared with a baseline of
keeping CO2 concentrations at 2""" levels$ !' high CO2
emissions, 2' medium CO2 emissions and )' reduced CO2
emissions brought about by policy measures to mitigate
climate change, but still higher than baseline levels.
Concrete structures were located in di*erent types of
sites e+posed to a range of water impacts, for e+ample,
submerged, in a tidal one and dry inland. Corrosion
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impacts were modelled from two sources$ e+posure to
CO2 in the atmosphere &-carbonation' and e+posure to
chloride, from salty water and air. /t was found that
reinforced concrete structures were more susceptible tocorrosion by carbonation, a*ected by increased CO2
levels in the atmosphere, than by chloride0induced
corrosion under all three future scenarios. 1y 2!"", it is
likely that 2"0" per cent of all concrete infrastructure, in
these two cities representing two climate types, will be
damaged, re3uiring maintenance or repairs. 4or the worst
case scenario, with the greatest CO2 emissions,
carbonation damage is up to 5" per cent higher than for
the base case &where emissions remain the same as year
2""" levels' for dry inland regions or temperate climates.
%tructures here would need e+tra attention to adapt to
the more damaging environment. #lthough higher
temperatures under climate change will increase
chlorine0induced corrosion under all emission scenarios,
the risk of corrosive damage will increase by a ma+imum
of !6 per cent under the worst case scenario, compared
with the base case scenario. 7evertheless the risk of
corrosion is already high for marine structures located in
tidal splash areas, so these structures especially re3uire
further protective measures to adapt to the e+tra risk of
damage caused by climate change. /n planning future
infrastructure using reinforced concrete, the costs
associated with adaptations &such as e+tra concrete cover
or special coatings' to mitigate anticipated increases in
corrosion damage should be factored into the design of
the structures.
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IMPACT OF CLIMATE CHANGE ON CORROION AN!
!AMAGE RI" TO CONCRETE INFRATR#CT#RE
"e$%ord&' Corrosion, climate change, risk assessment,
deterioration, carbonation
Ab&tract(
/ncreases in atmospheric CO2 concentrations, and
changes in temperature and humidity due to a changing
climate will, especially in the longer term, cause an
acceleration of deterioration processes and conse3uently
acceleration in the decline of the safety, serviceability
and durability of concrete infrastructure. #n investigation
of concrete carbonation0induced deterioration in typical
#ustralian and Chinese cities under a changing climate is
described in this paper. /t is based on 8onte0Carlo
simulation analysis that involves three emission
scenarios, i.e. #!1, #!4/ and 66" ppm stabilisation. he
probabilistic analysis included the uncertainty of climate
predictions, deterioration processes, material properties,
dimensions, and predictive models. (eterioration of
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concrete structures is represented by the probability of
reinforcement corrosion initiation and corrosion induced
damage at a given calendar year between 2"!" and
2!"", and all of them are a*ected by the changingclimate depending on locations. /t was found that
carbonation depths may increase by more than 69 for
inland locations in #ustralia. /t was also found that
carbonation0induced damage risks can increase threefold
by 2!"" to 29 for Canberra. he :ndings provide a basis
for the development of climate adaptation strategies
through the improved design of concrete structures.
INTRO!#CTION
Concrete is the predominant construction type used in
critical infrastructure in many countries. he deterioration
rate of such structures depends not only on the
construction processes employed and the composition ofthe materials used but also on the environment.
/ncreases in atmospheric CO2 concentrations, and
changes in temperature and humidity due to a changing
climate will, especially in the longer term, cause an
acceleration of deterioration processes and conse3uently
acceleration in the decline of the safety, serviceability
and durability of concrete infrastructure. he/ntergovernmental ;anel on Climate Change fourth
assessment report &/;CC 2""
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trend. /n comparison with pre0industrial temperatures, the
best estimation of the temperature increase from !>>"
caused by increasing atmospheric CO2 concentration can
be ?;rofessor and (irector, Centre for /nfrastructure;erformance and @eliability, he Aniversity of 7ewcastle,
7%W, 2)"=, #ustralia B;h( Candidate, Centre for
/nfrastructure ;erformance and @eliability, he Aniversity
of 7ewcastle, 7%W, 2)"=, #ustralia C%/@O Climate
#daptation 4lagship and C%/@O Dcosystem %ciences,
Highett, Eic, #ustralia.
8ark F. %tewart, Gihengli ;eng and iaoming Wang
2.!IC for 66" ppm CO2, )."IC for
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predict concrete deterioration under a changing climate
in #ustralia, in terms of changes in probability of
reinforcement corrosion initiation and corrosion induced
damage due to &i' increase in the concentration of CO2 inthe atmosphere, and changes to temperature. hese time
and spatial variables will a*ect the penetration of
aggressive agents CO2 and chlorides into concrete, and
the corrosion rate once corrosion initiation occurs
&%tewart et al. 2"!!, 2"!2'. /t has been shown by Wang
et al. &2"!"c' that additional carbonation0induced
damage risks for the #!4/ emission scenario is up to !59
higher if there are no changes to how concrete structures
are designed or constructed. /n practical terms, this is
e3uivalent to e+pecting that an additional !59 of all
concrete surfaces by the year 2!"" will be damaged and
in need of costly maintenance or repair. While there is
much research on deterioration of concrete studies, there
is relatively little research on how deterioration is
a*ected by a changing climate. %tewart and ;eng &2"!"'
used a simpli:ed deterioration model and global /;CC
&2""
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damage &severe cracking' for concrete infrastructure for
the #ustralian cities of %ydney and Canberra. /t was found
that carbonation0induced damage risks increases to 2"9
to "9 for #!4/, #!1 and 66" ppm emission scenarios. he additional damage risks for chloride0induced
corrosion is only )9 over the same time period due to
temperature increase, but without consideration of ocean
acidity change in marine e+posure. However, these
models still relied on relatively straightforward time0
dependent deterioration models, and ignored the e*ect of
changes in humidity on the deterioration process. he
e*ect of climate change on chloride0induced corrosion
has also been the subject of relatively little research,
however, 1astidas0#rteaga et al. &2"!"' have calculated
60!69 increases in probability of corrosion initiation due
to climate change. alukdar et al. &2"!2' have predicted
carbonation depths in Canada for climate change
scenarios, but did so using a deterministic model and
assuming constant @H. #n investigation of concrete
carbonation0induced deterioration in typical #ustralian
and Chinese cities under a changing climate is described
in this paper. /mproved deterioration models are used
that accurately predict carbonation depth when CO2
levels, temperature and humidity are timedependent
variables. /t is based on 8onte0Carlo simulation analysis
that involves three emission scenarios, i.e. #!1, #!4/ and
66" ppm stabilisation, representing medium, high and
policy0intervened FHF emission scenarios. he
probabilistic analysis included the time0dependent
changes in atmospheric CO2 concentration, temperature
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and humidity, and the uncertainty of climate predictions,
deterioration processes, material properties, dimensions,
and predictive models. (eterioration of concrete
structures is represented by the probability ofreinforcement corrosion initiation and corrosion induced
damage at a given calendar year between 2"!" and
2!"", and all of them are more or less a*ected by the
changing climate depending on locations. his paper
seeks to provide insights into the likely impacts of climate
change on the durability and damage risks of concrete
structures in #ustralia and China, under a range of
climate change scenarios, which will have similar
implications for other countries. he :ndings from the
investigation provide a basis for the development of
climate adaptation through the improved design of
concrete structures. %ince the main environmental driver
to increased concrete deterioration is CO2 concentration,
temperature and humidity, then this will a*ect all
concrete infrastructure globally, not just #ustralia or
China. While the present study focuses on concrete
infrastructure, changes in temperature and relative
humidity will also a*ect the corrosion of steel structures,
but these e*ects are beyond the scope of the present
paper.
2 ;@O1#1/G/%/C 8O(DGG/7F O4 C#@1O7#/O70/7(ACD( (#8#FD @/%J%
2.! #nthropogenic #spects of Climate Change 4uture
climate was projected by de:ning carbon emission
scenarios in relation to changes in population, economy,
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technology, energy, land use and agriculture, represented
by a total of four scenario families, i.e., #!, #2, 1! and 12
&/;CC 2"">5',
speci:cally related to #!4/, #!1 and 66" ppm CO2
stabilisation scenarios. heir low and upper bounds are
also described to consider CO2 projection modelling
errors. /f low and high values shown in 4igure ! are taken
as !"th and >"th percentiles, respectively, of a normal
distribution then the statistical parameters for CO2
concentrations are$ mean LCO2&t' is e3ual to mid value,
and standard deviation MCO2&t' is &high0low'N2.65. he
COE increases with time to a ma+imum value of
appro+imately "."5 for all emission scenarios. 4or the
reference &best' emission scenario based on constant
year 2""" CO2 concentration then LCO2&t' )5>.2 ppm
and MCO2&t' ". /n all cases the probability distributions
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are censored at year 2""" CO2 concentration. o project
spatially dependent temperature increases in the future
under di*erent emission scenarios, various climate
models or #tmosphere0Ocean Feneral Circulation 8odelsOFC8s' have been developed based on physical
principles at the continental scale. %electing an #OFC8 to
be used in an impact assessment is not a trivial task,
given the variety of models. he /;CC suggested that due
to the varying sets of strengths and weaknesses of
various #OFC8s, no single model can be considered the
best. herefore, it is necessary to use multiple models to
take into account the uncertainties of models in any
impact assessment. /n the current study, climate
projections from nine climate models are used 0 for more
details see Wang et al. &2"!"' and /;CC &2""
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e+ample, 4igure 2 shows the projected median
temperatures for the lowest and highest of the nine FC8
projections, for #!4/, #!1, 66" ppm and Kear 2"""
emission scenarios for %ydney, Canberra and iamen. he mid global temperature mid&t' is modelled as a
normally distributed random variable where the standard
deviation M&t' is &high0low'N2.65. he Coefficient of
Eariation &COE' increases with time from ".) for t2"""
to a ma+imum value of appro+imately ". to ".6 for all
emission scenarios. /n all cases the probability
distributions of mid&t' are censored at ero temperature
rise.
2.2 ime to Corrosion /nitiation Carbonation depth
depends on many parameters$ concrete 3uality, concrete
cover, relative humidity, ambient carbon dio+ide
concentration and others. he impact of carbonation has
been studied by many researchers and various
mathematical models have been developed with the
purpose of predicting carbonation depths &for review see
e.g., (uracrete !>>=, %tewart et al. 2""2'. /t is observed
that corrosion may occur when the distance between the
carbonation front and the reinforcement bar surface is
less than !06 mm &e.g., Koon et al. 2""
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&!>>=', Koon et al. &2""
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&de Garrard !>>>'$ &)' 4our new variables are now
included$ !. CO2&t' time0dependent increase in
atmospheric CO2 concentration, 2. ksite factor to
account for increased CO2 levels in non0remoteenvironments, ). f&t' time0dependent change in
di*usion coeUcient due to changes in temperature, and
. f@H&t' time0dependent change in di*usion coeUcient
due to changes in relative humidity. # number of studies
have shown elevated CO2 levels in urban environments
due to higher pollution, e+haust fumes, etc. %tewart et al.
&2""2' recorded CO2 concentrations of up to 6
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and Juwait and values of ksite calculated for these three
categories. #s most infrastructure are close to the
ground, height impact has been taken into consideration
when observation height is larger than )" m and so amultiplication factor of !.""< is applied to observation
values made at height larger than )" m. %ince the sie of
every city is di*erent, the de:nitions of rural, suburban
and urban areas depend on the sie of the city. /n order to
make ksite comparable, the de:nition of rural, suburban
and urban are given as follows. able 2 de:nes an urban
area based on population sie and distance from the
central business district &C1(' or downtown area. /f the
population of the city is less than ".6 million then the city
is considered as suburban. # rural area is de:ned as the
area outside of cities and towns, and typically much of
the land is devoted to agriculture. #n area that is neither
rural nor urban is de:ned as suburban. able ) shows the
statistical parameters for ksite obtained from the data. #s
e+pected, ksite increases for urban areas, most likely due
to higher pollution levels and -urban domes. ;opulation
&million' ".6 0 ! !02 206 60!"to 2.6. he @H factor f@H
e+ceeds one when @H is less than 569, and reduces to
ero when @H is e3ual to !""9. #s presented by
@ichardson &!>==' reports that insuUcient water is
available for carbonation to commence for a relative
humidity of 269 and lessT hence, a lower limit of
@H269 is set. Carbonation tends to be highest for
relative humidities @H&t' of 6"9 to
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for increases in CO2 concentrations it needs to be
recognised that D3n. &!' is a point0in0time predictive
model 0 i.e., the carbonation depth at time t assumes that
CO2 is constant, and assumes that ( is constant for alltimes up to time t. %tewart et al. &2"!!' considered this
phenomenon and calculated carbonation depths due to
enhanced atmospheric CO2 concentration conditions
using the average CO2 concentration over the time
period, and not the peak value at time t. /f we consider
the carbonation process as a steady state modelled by
4icks 4irst Gaw, where CO2 concentration and
temperature and @H correction factors are time0
dependent, then &
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statistical parameters for a temperature of 2" oC given
by (uracrete &!>>=', see able . hese values take into
account the concrete grades suggested for the
corresponding e+posure classes. #n increase intemperature will increase corrosion rate, and the model
described by (uracrete &2"""' is used$ &=' where icorr02"
is the corrosion rate at 2" oC given in able , and
J"."26 if &t'2" oC. (uracrete &2"""' notes that D3n.
&5' is a close correlation to #rrhenius e3uation, at least
for temperature below 2" o C, but may be conservative
for &t'X2" oC. # 2o C temperature increase will increase
the corrosion rate by !69. here is little data on time0
dependent e*ects on corrosion rate for carbonated @C
structures. Hence, the present analysis assumes a time0
invariant corrosion rate for carbonation. his is likely to
be a conservative assumption as corrosion rate will
generally decrease with time due to the build up of rust
products thus impeding the corrosion process &e.g., Eu
and %tewart 2"""'. D+posure Class 8ean %tandard
(eviation (istribution C! 0 (ry "."a "." Gognormal C2 0
Wet0 rarely dry &unsheltered' ".)6 L#Ncm2 ".26>
L#Ncm2 Gognormal C) 0 8oderate humidity &sheltered'
".!>='. 2. ime to Crack /nitiation &!st' #s
there is a porous one around the steel reinforcing bar
the corrosion products must :rstly :ll this porous one
before the products start to induce internal pressure on
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the surrounding concrete. herefore, not all corrosion
products contribute to the e+pansive pressure on the
concrete. his approach to crack initiation has been used
by Dl 8aaddawy and %ouki &2""
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con:nement around e+ternal reinforcing bars. /f the
reinforcing bar is in an internal location then kc!, but
for rebars located at edges and corners of @C structures
then kc is in the range of !.2 to !.. #lthough the data islimited, there appears to be a trend where kc increases
as Zcp increases. /n this study kc is taken as !.". #
statistical analysis of model accuracy to account for
variabilities between model prediction and e+perimental
data is essential for stochastic or reliability analyses
where statistics for model error are re3uired. Hence, the
statistics for model error for rcrack &8Drcrack' are$
mean&8Drcrack' !." and COE&8Drcrack' ".">
&8ullard and %tewart 2"!!'. 4or more details of this
improved cover cracking model see 8ullard and %tewart
&2"!!'. he cover cracking model developed by 8ullard
and %tewart &2"!!' was based on chloride0induced
corrosion. Concrete strength is time0variant, and the time0
dependent increase in concrete compressive strength
after one year using the #C/ method is fc!.!52fc&2='
where fc&2=' is the 2= day compressive strength. ime0
dependent gains in strength beyond one year are not
considered in the present analysis. 2.5 ime to Corrosion
(amage &sev' %ince corrosion rate is a time0dependent
function of temperature then times to corrosion damage
need to be corrected since D3ns. &>0!2' assume a time0
invariant &constant' corrosion rate. /f we assume that the
amount of corrosion products needed to cause cracking
&mcorr' for a constant corrosion rate is directly
proportional to icorr&!stQsev' then
mcorricorr&!stQsev'. he time to corrosion damage
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for a variable corrosion rate &sp' is such that the
corrosion amounts &mcorr' for constant and variable
corrosion rates are e3ual. /t follows that sp is obtained
from solving the unknown sp from the followinge3uation$ &!)racking of the concrete surface to reach a
crack width of w mm is$
2.5 ;robability of ime to Corrosion /nitiation
Corrosion will take place when the carbonation depth
reaches the surface of the reinforcing bar, and so the
cumulative probability of corrosion initiation at time t is
&!' where +c&t' is the carbonation depth obtained from
D3n. &
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Computational 8ethod
8onte0Carlo simulation is used as a computational
method for the time0dependent reliability analysis. 7ote
that the CO2 concentration is fully correlated with time. )@D%AG% ).! (urability (esign %peci:cations in #ustralia
and China Dnvironmental e+posure in #ustralia is
classi:ed by the #ustralian Concrete %tructures Code
#%)5""02""> as three climatic ones &arid, temperate
and tropical', see 4igure . he selected sites of %ydney
and Canberra represent two very di*erent durability
design re3uirements with design cover for many locationsin %ydney being "06" mm due to its coastal location,
and )" mm cover for Canberra due to its inland location.
Climatic Pones (e:ned by the #ustralian Concrete
Code#%)5"".
Concrete inside buildings with low air humidity, or that ispermanently submerged in water, generally has a low
e+posure to carbonation, while concrete surfaces subject
to long0term periodic water contact, concrete inside
buildings with moderate0to0high air humidity, and
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e+ternal concrete sheltered from rain have high
e+posures to carbonation. 4or this reason the reliability
analyses to follow will focus on corrosion predictions for
sheltered structures for carbonation. he durabilitydesign re3uirements speci:ed in #%)5"" relate to
minimum concrete cover and concrete compressive
strength, and assume standard formwork and
compaction. able 6 shows the durability design
speci:cations related to the #%)5"" e+posure
classi:cations #! to C for carbonation. able 5 presents
the Chinese durability design re3uirements for bridges
&F.(520 2""'. Clearly, the environmental categories
are de:ned di*erently, however, the durability
re3uirements for bridges in Chinese standard are
generally the same as #ustralian standards, but the
re3uirements for normal buildings &F16""!"02"!" 2"!"'
are lower than that for bridges. able 6 also shows the
parameter values for the deterioration models. he
e+posure classi:cations of most relevance for concrete
infrastructure in %ydney and Canberra are near0coastal
&1!' and coastal e+cluding tidal and splash ones &12' for
%ydney, and #2 for Canberra.
able 5$ Chinese (urability (esign %peci:cations
&F.(5202""' and (eterioration 8odels, for Carbonation
in %heltered Conditions, and for 1ridge %tructures &;iers,Darth @etaining %tructures, Culverts, 1eams, ;lates,
#rches, %pandrel %tructures'. able < shows the statistical
parameters for corrosion parameters, material properties
and dimensions 0 these are representative of concrete
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structures in #ustralia. Clearly, the uncertainty and
variability of deterioration parameters is considerable.
However, improved deterioration modelling may reduce
this variability, as could 1ayesian updating based onconditions or other site speci:c data for e+isting or new
structures. Anless noted otherwise, all results in the
following sections refer to the average of nine FC8
temperature simulations. @einforcement bar diameter is
2" mm, and ksite is based on statistical parameters for
an urban environment for %ydney and iamen, and
suburban environment for Canberra . 7ote that the same
value of ksite applies for all emission scenarios including
the year 2""" scenario.
%tatistical ;arameters for Corrosion ;arameters, 8aterial
;roperties and (imensions he impact assessment is
focused primarily on the relative change in corrosion
initiation and damage risks due to enhanced CO2 levels,
temperature and humidity when compared to year 2"""levels, and not on the absolute estimates of risk. he
deterioration models are mostly derived from the !>>50
!>>> Duropean (uracrete project which has formed the
basis for the probabilistic durability design of many
important structures and the :b model code for service
life design &:b 2""5'. However, many other deterioration
models have been developed for concrete durability,which if deemed more appropriate, can readily be
incorporated into the stochastic and reliability framework
developed in the present study. While di*erent
deterioration models will produce di*erent estimates of
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absolute risk, deterioration model selection will have
signi:cantly less inRuence on comparative risks. ).2
Corrosion (amage @isks 4igure 6 shows the mean
carbonation depth for four emission scenarios ande+posure classi:cations, for %ydney, Canberra and
iamen. he #ustralian Concrete %tructures Code
#%)5""0 2""> %)5"" 2"">' speci:es improved
concrete compressive strength and other enhanced
durability design speci:cations, which will result in a
reduced rate of carbonation. his is evident in 4igure 6&a'
where e+posure classi:cation C with wNc"." concrete
has a carbonation depth signi:cantly less than e+posure
classi:cation #2 with wNc".65. he #!4/, #!1 and 66"
ppm emission scenarios have a signi:cant e*ect on
carbonation depths, but the carbonation depths for these
emission scenarios vary by no more than 5 mm by 2!""
in all the three cities. 4or e+ample, in 4igure 6&b', the #!4/
emission scenario increases carbonation depth by
appro+imately 69 when compared to reference year
2""" CO2 emissions for e+posure classi:cation #2 for
Canberra. he e*ect of the nine FC8 temperature
prediction models on probabilities of corrosion initiation
and corrosion damage is shown in %tewart et al.s work
&%tewart, Wang et al. 2"!!', for #!4/ emission scenario
and #! e+posure classi:cation in %ydney. here are 5.=9
and !
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likelihood of corrosion initiation is less than ".")9, and
less than "."")9 for corrosion damage, for e+posure
classi:cations 12 and C in %ydney, see 4igure 5. hese
probabilities are negligible irrespective of the emissionscenario. Corrosion initiation and corrosion damage risks
are highest for e+posure classi:cations #2 and 1!, as
these are e+posures most susceptible to carbonation for
structures located well away from the coast. here is
unlikely to be any signi:cant corrosion damage for the
:rst "06" years service life, but the likelihood of
corrosion damage then increases to !9 to 2.69 for #!4/,
#!1 and 66" ppm emission scenarios for %ydney. /n
practical terms, this is e3uivalent to e+pecting that !9 to
2.69 of every concrete surface by the year 2!"" will be
damaged and in need of maintenance or repair. Of most
interest in this paper is the e+posure classi:cations 1!
and 12 for %ydney &up to 6"km from coast'. he
probability of corrosion damage for the worst case
scenario !4/' is up to !" times higher than that
observed for the reference &best' mitigation scenario for
1!, and for 12 e+posure classi:cations. 4or Canberra,
damage risks increase to 29 by 2!"" for emission
scenarion #!4/. 4or iamens bridges there is up to 69
probabilities of 8ark F. %tewart, Gihengli ;eng and
iaoming Wang corrosion damage for #!4/, #!1 and 66"
ppm emission scenarios by 2!"". his indicates that the
higher CO2 concentration could lead to a signi:cant
likelihood and e+tent of corrosion damage that may need
costly and disruptive repairs during the service life of
many concrete structures in #ustralia, China, and
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elsewhere. 1ecause the de:nition of environmental
e+posure in the two countries standards are di*erent,
the results cannot be compared directly. However, in
order to make the comparison between structures in%ydney and iamen more reasonable, the results of
similar structures could make sense. 4or e+ample, we
could e+plore how does the damage risk for a bridge 6
km from the coast in %ydney di*ers from one in iamen
that is also 6 km from the coast for the same e+posure
and same use. herefore, the e+posure classi:cation for
structures in %ydney and bridges in iamen should be 1!
and //, respectively. /n both cases, ksite is based on
statistical parameters for an urban environment &see
able )'. he results of all the possible e+posure
categories for %ydney and iamen are presented in able
=. /t can be easily :nd out from able = that the corrosion
of iamens bridges are more severe than in %ydney. 4or
beams of a bridge 6 km from the coast in %ydney and
iamen, the e+posures for them are 1!and //,
respectively. he probabilities of corrosion damage for
iamens bridges are double than that of %ydney. he
warmer weather and greater temperature increase in the
>" years prediction in iamen might be one cause of
higher damage risks, but lower 4c and cover might be
more critical.
CO7CGA%/O7%
his paper describes a probabilistic and reliability0based
approach that predicts the probability of corrosion
initiation and damage &severe cracking' for concrete
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infrastructure subjected to carbonationinduced corrosion
resulting from elevated CO2 levels, @H and temperatures
due to a changing climate. he probabilistic analysis
included the uncertainty of CO2 concentration,deterioration processes, material properties, dimensions,
and predictive models. /t was found that
carbonationinduced damage risks can increase threefold
by 2!"" to 29 for Canberra. he results were most
sensitive to increases in atmospheric CO2. hese
structures may merit appropriate and cost0e*ective
climate adaptation measures to ameliorate the adverse
e*ects of a changing climate.
@D4D@D7CD%
#%)5"". 2"">. Concrete %tructures. %ydney$ %tandards
#ustralia. 1astidas0#rteaga, D., Chateauneuf, #., %anche0
%ilva, 8., 1ressolette, ;h., and %choefs, 4. 2"!". /nRuence
of weather and global warming in chloride ingress into
concrete$ a stochastic approach, %tructural %afety, )2$
2)=02>. (ay, .#., Fober, ;., iaong, 4.%. and Went, D.
2""2. emporal ;atterns in 7ear %urface CO2
Concentrations over Contrasting Eegetation ypes in the
;heoni+ 8etropolitan #rea. #griculture and 4orest
8eteorology. !!"$ 22>026. de Garrard, 4. !>>>. Concrete
8i+tures ;roportioning$ a %cienti:c #pproach. Gondon$
D[47 %pon. (uraCrete. !>>=. 8odelling of (egradation,(uraCrete 0 ;robabilistic ;erformance based (urability
(esign of Concrete %tructures. DA \ 1rite Du@am ///.
Contract 1@;@0C>60"!)2. ;roject 1D>60 !)
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Eariables in the Gimit %tate 4unctions. (uraCrete 0
;robabilistic ;erformance based (urability (esign of
Concrete %tructures, DA 0 1rite Du@am ///. Contract 1@;@0
C>60"!)2. ;roject 1D>60!), !)" p. (uraCrete.2"""b. ;robabilistic Calculations, (uraCrete 0 ;robabilistic
;erformance based (urability (esign of Concrete
%tructures. DA 0 1rite Du@am ///. Contract 1@;@0C>60
"!)2. ;roject 1D>60 !)
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!"2!0!")
@ichardson,8.F. !>==. Carbonation of reinforced
concrete$ /ts Causes and 8anagement. @ussel, (.,
1asheer, ;.#.8., @ankin, F./.1. and Gong, #.D.. 2""!. D*ect
of relative humidity and air permeability on prediction of
the rate of carbonation of concrete. ;roceeding of the
/nstitution of Civil Dngineers0%tructures and 1uildings.
!5&)'$)!>0)25. %tewart, 8.F., eply, 1. and Jralova, H.
2""2. he D*ect of emporal and %patial Eariability of
#mbient Carbon (io+ide Concentrations on Carbonation
of @C %tructures. >th /nternational Conference on
(urability of 1uilding 8aterials and Components. C%/@O.
;aper 25 &C(0@O8'. %tewart, 8.F. and ;eng, . 2"!".
Gife Cycle Cost #ssessment of Climate Change #daptation
8easures to 8inimise Carbonation0/nduced Corrosion
@isks, /nternational ournal of Dngineering Ander
Ancertainty$ Haards, #ssessment and 8itigation, 2&!02'$
)605. %tewart, 8.F., Wang, .8. and 7guyen, 8.7. 2"!!.
Climate change impact and risks of concrete
infrastructure deterioration. Dngineering %tructures ))&'$
!)250!))
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Conte+t of Flobal Climate Change$ ;arts ! and 2, Cement
[ Concrete Composites &in press'. Eu, J.#.. and %tewart,
8.F. 2""". %tructural @eliability of Concrete 1ridges
/ncluding /mproved Chloride0induced Corrosion 8odels.%tructural %afety. 22&'$ )!)0))). Wang, ., Chen, (. and
@en, P. 2"!". #ssessment of climate change impact on
residential building heating and cooling energy
re3uirement in #ustralia, 1uilding and Dnvironment,
6&
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?oF +-/o% 1
1oF +/1o% <
0
o
F +/
o
% //@oF +@o% /@
;oF +!/o% />
-oF +!?o% 3et will not occur
#he retardation of initial setting time by the use of admixture is affected
by three factors, that is, the ambient temperature, the dosage used, and
the time of adding to the batch.
Temperat%re E$$e:t !n &etardati!n !$ /nitia" Settin# Time
#emperature can have a detrimental effect to concrete strength
development. owever, proper cold weather concrete curing will
enhance concrete strength development. ot weather is defined as any
combination is high ambient temperature, high concrete temperature,low relative humidity, and wind velocity. %old weather period, as
defined by A%I %ommittee ;1, is when one of the following conditions
occur for three consecutive days9
• Average daily air temperature is less than @oF
• #he air temperature is not greater than 0oF for more than one!half
of any -@ hour period.
#he effect of concrete temperature and retardation of setting time is
given by "%A in the chart below. It is concluded from the chart that the
retardation effect is more pronounced when a higher concrete
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temperature is used.
$ffect of %oncrete #emperature and 7etarder on 3etting #ime
7etardation of setting time is influenced by the type of admixtures used.#he chart below illustrates the effect of various lignosufonates +/ and -
and carboxylic +; and @ admixtures on setting time.
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#he time of adding the admixture to the batch here is significant and
may affect final results. &ore retardation may take place if the
admixture is added as the last ingredient and the cement is wet.
D!a#e E$$e:t !n &etardati!n !$ /nitia" Settin# Time
igher dosage may be used up to a certain level only prior to when any
rapid stiffening and slump loss occurs. #his admixture is sensitive to
ambient temperature when introduced to the batch. #he lower the
ambient temperatures, the longer time of setting for the concrete will be.
#he following figure is used to estimate initial setting time according to
the dosage of retarder and concrete ambient temperature.
Increasing Initial 3etting #ime with 7etarder %ontent
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Remember When Experts Predicted Climate Change Was "Global"? The U.S. Warming Pause
(click on to enlarge)
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Per NOAA, the U.S. warming pause (aka the 'Hiatus') hasnow achieved a !"#ear sta$$ (see ad%acent chart). &nact, a s$ight coo$ing has een the trend over this period.
ememer the predicted g$oa$ warming # e*perts+ hesame -e*perts- who predicted that hurricanes wou$d
ecome stronger and more reuent as a resu$t o theg$oa$ warming " which a$so did not happen.
As the empirica$ c$imate datasets revea$, the predictedg$oa$ warming has amounted to aout ni$ or c$ose totwo decades. And ecause o this, the g$oa$ warmingscientists recent$# resorted to e*ceptiona$ arications o
temperature datasets to produce -warming- thatdisappears the 'Pause'.
/inning up c$imate change ears in anticipation othe Paris 012 3OP0 c$imate travest# show seems to e
the driving orce ehind the most recent who$esa$e ake"warming production.
4ack to the inc$uded chart. As depicted, the !"#ear
pause inc$udes not on$# the continenta$ U.S. (at "1.567per centur# coo$ing) ut a$so the states o 8irginia and9ar#$and, oth at "1.267 per centur# coo$ing.
:h# depict those two state's temperature trends+
4ecause those states surround the metropo$itan ;istricto 3o$umia where edera$ ureaucrats, U.S. e$ectedrepresentatives and administration oicia$s pontiicate
aout the rapid and dangerous -g$oa$ warming-. hesee$ites $ive and work in the ;.3. micro"c$imate warming
u$e that is a direct resu$t o edera$ ta*pa#er aspha$t,stee$, concrete and airports with ver# hot %et e*hausts,which in comination have produced a rapid$#warminguran heat is$and (UH&).
http://www.nature.com/news/climate-change-the-case-of-the-missing-heat-1.14525https://stevengoddard.wordpress.com/2015/09/15/30-years-of-hurricane-incompetence-from-hansen-and-emanuel/http://www.climatedepot.com/2015/09/12/no-category-3-hurricanes-making-us-landfall-in-nearly-10-years/http://www.c3headlines.com/modern-temperatures-chartsgraphs.htmlhttp://wattsupwiththat.com/2015/10/01/is-there-evidence-of-frantic-researchers-adjusting-unsuitable-data-now-includes-july-data/http://joannenova.com.au/2015/09/headlines-contradictory-pressure-intense-meetings-in-bonn-ny-lima-its-paris-paris-paris/http://climate4you.com/UrbanHeatIsland.htmhttps://stevengoddard.wordpress.com/2015/09/15/30-years-of-hurricane-incompetence-from-hansen-and-emanuel/http://www.climatedepot.com/2015/09/12/no-category-3-hurricanes-making-us-landfall-in-nearly-10-years/http://www.c3headlines.com/modern-temperatures-chartsgraphs.htmlhttp://wattsupwiththat.com/2015/10/01/is-there-evidence-of-frantic-researchers-adjusting-unsuitable-data-now-includes-july-data/http://joannenova.com.au/2015/09/headlines-contradictory-pressure-intense-meetings-in-bonn-ny-lima-its-paris-paris-paris/http://climate4you.com/UrbanHeatIsland.htmhttp://www.nature.com/news/climate-change-the-case-of-the-missing-heat-1.14525
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he NOAA scientiic empirica$ evidence is rather c$ear andundenia$e. 7or most Americans, g$oa$ warming is notan issue and is deinite$# not impacting their dai$# $ives.
4ut or a minorit# o governing e$ites, who ovious$#created a hosti$e warming micro"c$imate or their work
environment, it has made them incapa$e odistinguishing the c$imate orest rom the micro"c$imate
trees, so"to"speak. Or, put another wa#, the# can'tdiscern the dierence etween c$imate rea$it# and c$imateantas#.
Hmmm....ma#e the est so$ution or saving the e$ites
rom their own, se$"created hosti$e and c$imate changetriggering environment is to disperse the edera$
government oices and personne$ across rura$ $ocationsthroughout the U.S.
EFFECT OF E)TREME COL! ON MATERIAL
An understanding of the effect of extreme cold on the elasticity,
durability, strength, and other physical characteristics of materials, and
the treatment that these materials should receive when exposed to such
temperatures is important. Where applicable and when re8uired,
information
on this subject can be obtained from manufacturers furnishing material
or
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e8uipment, and from 8ualified research laboratories.
Water
Fresh Water . )nder usual conditions, fresh water freeBes at a
temperaCture of ;-DF., forming solid ice and expanding about >E in
volume. It takes
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due to pressure decreases to the vanishing point.
3ea +salt water freeBes at approximately -
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volving the transfer of heat from the engine to K LM a li8uid, usually
water, and
Fig. / then cooling the li8uid by air through the use of a radiator +see
Fig. /.
Water was naturally selected as a cooling medium because of its
availability
and relatively high heat transfer properties. owever, water has certain
shortC
comings, the most important of which are its high freeBing point and its
corrosive action on metal parts of the cooling system, which may result
in
rust clogging and metal perforation. #hese two major disadvantages arelargely
overcome by adding materials to the water to prevent freeBing in winter,
and
special chemical ingredients to inhibit corrosion. 4ils, sug e a rs, and
inorganic
salt solutions are generally regarded as unsatisfactory antifreeBe
materials.
In the )nited 3tates and %anada, approximately one!third of the cars
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re8uiring
antifreeBe are protected with ethylene glycol +glycol base products and
most of the remaining two0thirds employ methylalcohol &methanol' or ethyl alcohol ðanol' type
solutions. /n the #rctic, ethylene glycol base
products are used almost entirely.
he antifreee e*ectiveness of methyl and
ethyl alcohols and ethyleneglycol types is shown in
4igure 2. hese curves bring out several facts.
4irst, the methyl alcohol type give the greatest
freeing protection per unit volume, followed by
ethylene glycol, and then the ethyl alcohol.
%econd, all three li3uids are capable of depressing
the freeing point of water to thelowest
atmospheric temperatures likely to beencountered. he :rst reason is based only on
freeing protection per gallon, and does not take
into con\ sideration the e+tra 3uantities of the low0
boiling0point alcohol antifreee solutions re3uired
after the initial :lling because of boil0away losses,
or the superiority of the comparatively high boilingpoint of ethylene glycol solution in preventing such
losses. 4or antifreee solutions protecting down to
^2"I4., the boiling point of the ethylene glycol
solution is 22 = ) I4.while the boiling point of the
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alcohol0base solution is !="I4.Anlike water,
antifreee solutions do not solidify when e+posed
to
temperatures slightly below their freeing points
but instead tend to form slush. he minimum
temperatures to which solutions of the three types
of antifreee having a freeing point of "I4. may be
e+posed without giving rise to overheating or other
diUculties immediately after the engine is startedare$ methyl alcohol, ^2.6I to ^6.6I4.T ethyl alcohol,
^6.6I to ^=."I4.T ethylene glycol, ^=."I to
^!!.6I4.
he lower the freeing point of the antifreee
solutions used, the further below this freeing
temperature is it possible to e+pose the solutionwithout fear of overheating, resulting from
circulation restricted by ice crystals @elation 1etween Concentrations and 4reeing
;rotections of Earious #ntifreee %olutions or slush ice,
after the engine started. 4rom 4igure 2 it is noted that
antifreee protection can be determined in volume per
cent concentration in water and easily reduced to pintsper gallon of solution &see able /'.
able /. ;ints of #ntifreee per Fallon %oulutions for
;rotection _
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down to Earious emperatures.
Protection
to, °F.
Methyl
alcohol
Ethyl
alcohol
Ethylene
glycol
^ Q !" ! ` 2 !N 2
" 2 ) 2 )N
^!" 2 ) )N ) !N
2"
^2"
) ) !N2 _
^)" ) !N2
^" ) ` 6 !N !N
^6" 6 )N !N2
In the case of ethylene glycol, the greatest freeBing protection that
can be obtained is G1-DF. which is given by a solution containing 1E
antiC freeBe and @E water. 3olutions containing more than 1E
ethyleglycol give less protection.
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*lycerim +glycerol is one of the acceptable nonvolatile antifreeBe
materials, but because of its relatively high cost compared to ethylene
glycol, and its many other important commercial uses, it is not used to
any great extent.Nerosene, freeBing point G1DF., had been used instandard automotive cooling systems in localities with extreme cold
climates. Its heat capacity is approximately one!half that of water, but
automobiles operating with kerosene as a coolant are subject to
overheating in warm weather. Additional disadvantages are its
unpleasant odor, flammability, and severe action on rubber hose.%are
should be taken to select an antifreeBe containing heavy!duty inhibitors.
#wo general types are in general use9 soluble oils and salts.
#he oil types are considered generally to be the most satisfactory.
:ehicle radiators filled with antifreeBe should be tagged showing type of
antifreeBe.
Fuels and ubricants
'uring World War II, special fuels and lubricants were developed
to overcome the difficulties in star gasoline and diesel engines
previously encountered in the Arctic. +3ee 2"etroleum "roducts for
Arctic Winter )se in Automotive $8uipment6 and 2#ractor!#ype
#ransportation )nits for Arctic
4perations6 for details on the improvements made on the various
properties of fuels and lubricants for low!temperature use.
In shipping fuels in drums it is important that only extra heavy
exportCtype drums be used. #his is necessary as this type drum can be
handled easier
in the cold and facilitates roping for dropping by parachute from planes.
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#he smooth drum is slippery when wet or covered with ice or snow and
it is difficult to rope and attach to a parachute.
#he recommendations of the manufacturer of any e8uipment should
be consulted regarding lubrication under cold conditions. &any
excellent lubricants
have been developed and used successfully in northern operations.
owever, it must be realiBed that at extreme temperatures oils and
greases become stiff.
If an engine has been shut down for any period of time the lubricant mayhave become so stiff that a fully charged battery will not turn the engine
over.
#his situation may be further aggravated because at such temperature
batteries lose much of their energy.
7ubber!like &aterial
#he general effect of reduced temperatures is the same for all
rubber!like materials. As the temperature is decreased the rubber passes
from a soft +easily deformed and elastic state to a more rigid state and
finally to a brittle glasslike condition. #he various commercial rubbers
differ appreciably as to the temperature ranges in which they pass
through these various states.
one of the available commercial rubbers are truly elastic at extremely
low temperatures +below G@DF.. ew rubber products stand up better
under cold conditions than old rubber. #he effect of temperature on
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rubber materials is predominantly physical and any chemical changes
which may take place can, on a practical basis, be ignored.
3ome new natural rubber materials are usable at low temperatures
approachingG0DF. but in the course of their use it is imperative that they
be not subjected to any force at an excessive velocity.
#hat is, rapid bending orflexing at or near such low temperatures will
result in breaking or even shattering of the rubber part. For example,
rubber tires will develop flat spots at low temperatures. #he tread of old
rubber tires will chip due to cold embittlement when subjected to force
or flexing. ew tires show less tendency to crack than do tires of oldrubber.
ower!temperature rubber!like materials are made by specifically
compounding the integral parts for low!temperature service. #wo
general classes of these have been developed9 normal natural rubber
material to operate +with care down to G@DF., and special rubber!like
material +natural rubber and butyl rubber for extreme low temperatures
to G?DF. &any of the large rubber and chemical companies that
specialiBe in rubber and synthetic rubberproducts are working on the
problem of providing rubber!like materials for use under extreme cold
conditions.
"lastics
&ost plastics contain a base material, the properties of which have
been modified by the incorporation of plasticiBers or fillers. $ach base
material is the foundation for a group of compositions related in general
behavior but differing from one another in individual physical
properties. 3uch basic
groups of plastics are9 acrylics, celluloses, nylons, ethylene , polymers,
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vinyl ester polymers, polyvinyl acetals, phenolics, urea resins, caseins
alkyds, neoprene, etc. groups which contain several different
compositions are subdivided into types. $ach type represents one or
more compositions, each of which is designed to give superior value ofsome specific property even at the expense of some other property.
#here is, for example, #ype neralJ #ype II, temperature resistantJ #ype
III, impact resistantJ #ype I:, moisture resistantJ etc. Where further
subdivision is re8uired, the typesare subdivided into grades. $ach grade
represents, at broadest, a very restricted number of common commercial
materials which are 8uite similar both chemically and physically. #hese
groups, types, and grades usually correspond to those given in the
specifications of the American 3ociety for #esting &aterials.
#he service success of an article of any plastic often depends as
much upon the design and fabrication processes as on the material itself.
#he
importance of selecting items of good workmanship in both design and
fabricaCtion for cold!weather operations cannot be overemphasiBed. #he
plasticsindustry has developed a background of practical experience in design,
fabrication, and testing of plastics, and should be consulted regarding
specific cold!weather problems.
#he importance of selecting the proper material and consulting with
plastic manufacturers concerning cold!weather problems cannot be
overstressed. It is important not only to select the proper material but to
use it properly in the field. #oo fre8uently, good plastics improperly
handled in the field failed, when the same material properly utiliBed
would have been entirely satisfactory.
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As an aid in understanding this field of material, a list of the more
important plastics by resin group and subgroup, trade names, available
forms, and commercial uses is given in #able I. +#he code for the
available forms is9 F, filamentsJ &, moldedJ 7, rodsJ 3, sheetingJ #,tubing. where applicable, comments on the effects of extreme
temperatures and care in use in the field are given in the text.
#he acrylics are perfectly clear and transparent. #hey have the best
resistance of all transparent plastics to sunlight and outdoor weathering,
and will tolerate years of exposure without significant loss of properties.
#hey possess a good combination of flexibility with shatter resistance
and rigidity.
#heir impact strength is lower than the celluloses, but the effect of
extreme low temperatures upon this property is much less pronouncedJ
hence, articles designed for use at ordinary temperatures will not show
excessive embrittlement
at G0DF.
%ellulose nitrate is the toughest of all thermoplastics. It has low
water absorption and is resistant to mild acids. At G0DF., its impact
strength
is about ;0E of its impact strength at normal temperatures +??DF..
%ellulose nitrate is very flammableJ it is not suitable for prolonged
service in outdoor sunlight for it turns yellow and becomes brittle.
%ellulose acetate is comparatively tough. Its low temperatureimpact strength and embrittlement characteristics are inferior to those of
cellulose
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able /. %ome /mportant Commercial ;lastics. _
Resin
group and
subgroup
Trade
names
Forms
availa
ble
Uses
#crylics$
8ethyl
methacrylate
resin
Gucite
;le+igla
s
8, @,
%,
8, @, %
Windshields,
goggles,
dentures,
arti:cial eyes,
drafting in\
struments,
automotive
parts,
aircraft
enclosures
Celluloses$
Cellulose
nitrate
Celluloid
7itron
7i+on
CN7
@, %, ,
4
@, %,
@, %,
4ountain pens
and pencils,
drawinginstruments,
spectacle
frames, bottle
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;yralin @, %, caps, toilet
seats,
tool handles,shoelace tips,
:lm
Cellulose
acetate
4ibestos
Gumarit
h
7i+on
CN#
;lastoce
le
@, %,
@, %, ,
8
@, %, ,
8
@, %,
Containers,
luggage, food
cases,
truck curtains
Chemac
o
Hercules
Joppers
enite /
8
8
8
8
Jnobs, goggle
frames,
combs,
brushes, tool
handles,
safety
goggles, eye
shields,
automotive
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parts and
housings
Cellulose
acetate
butyrate
enite // 8 elephones,
steering
wheels,
:lm spools,
radio
housings,knobs
and pulls, light
supports, coil
spools, brush
backs
Dthyl
Cellulose
Celcon
Chemac
o
Dthocel
Hercules
Joppers
8
8
8, %
8
8
@adio
housings,
toothbrushes,
pen
and pencilbarrels, tool
handles,
knobs and
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7i+on
DNC
8, % pulls,
Rashlight
cases
7ylon$
e+tile
:lament
types
4 e+tile :ber,
ropes, lines,
hose,
tents,
stockings,
clothing,
bristles,
surgical
sutures
/njection,
e+trusion
and
alcohol0
soluble
types
8, % /njection and
compressedmolding,
covering for
wire and
sheets,
solutioncastings, small
bearings,
specialty
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containers,
electrical
coil forms andinsulators,
small
gears, cams,
coatings
able /. %ome /mportant Commercial ;lastics &contd'.
Resin group
and
subgroup
Trade
names
Forms
availa
ble
Uses
Dthylene
plymers$
;olyethylene
;olythene
4, 8, %,
4, 8, %,
4ilms, liners,
closures,
wrappings
for froen
food,
primarycable, _
insulating
material,
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coating for
weatherpro
of wire
;olytetraRuor
o\
ethylene
eRon 8, @, %,
4ilms,
tubes, tapes
and special
applications
made byrolling,
drawing, or
machining
;olyvinyl
acetals$
;olyvinyl
formal
4ormvar 8 /nsulating
enamel,base for
electric
wires,
phonograph
records
;olyvinyl
butyral
1utacite
%aRe+
8, %
%
;lastic
interlayer,
laminated
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Einylite 8, % for safety
glass,
sheeting,
and
coatings for
dustproof
and
waterproo:
ng fabrics
Einyl ester
polymers$
;olyvinyl
chloride
Feon
8arvinol
;liovic
Altron
Einylite
8, %
8
8, %
8, %
8, %
acketing
material on
electric
wires and
cables,water0
repellent
garments,
shower
curtains,
garment
bags,
upholstery,
belts, Roor
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coverings,
overlays for
maps,
phonograph
records
;olyvinyliden
e resins$
4inylidene
chloride
%aran 4, 8, Hoses,
Re+ible
tubing, rigidpipe,
lined steel
pipe,
moisture0
resistant
:lms and
fabrics for
upholstery
and
transportati
on seating
;olystyrene 1akelite
Cere+
8
8
%tando*
insulators,
antenna in\
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Chemac
o
Joppers
Goale+
Goalin
Gustre+
%tyron
8
8
8
8
8
8
sulators,
radio coil
forms,
telephone
e3uipment,
Ruorescent
light
:+tures,wall til s e ,
combs, _
knobs and
pulls,
shaver
housings,
camera
cases,
refrigerator
parts,
bottle caps
;olystrene
e+panded
%tyrofoa
m
% /nsulating
material in
refrigera\
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tion
construction
, buoyancyagent
for life rafts
and small
metal
boats
able /. %ome /mportant Commercial ;lastics &contd'.
Resin group
and
subgroup
Trade
names
Forms
available
Uses
;henolics$
;henol0
formaldehyde
resin
1akelite
(ure
(urite
@esino+
8
8
8
8
Camera
cases,
photographic
:lm
spools,
handles,
instruments,
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bo+es, radio
cabinets,
ignition
parts,
instrument
panels,
pulleys,
housings,
terminal
blocks,
telephone
parts, goggle
frames,
wheels
8elamine
resin$
8elamine0
formalde\
hyde
8elmac
;laskon
@esime
ne
8
8
8
Compression
moldings,
electrical
:ttings,
sockets, foodcontainers
Area resins$ 1eetle 8 1uttons,
tableware,
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Area0
formaldehyde
;laskon 8 bo+es,
electrical
parts andlighting
reRectors
%ynthetic
rubber$
Chlorobutadie
ne
7eopre
ne
8, %, Hose,
molded
parts,weather
strip\
ping, wire
and cable
jacketing
adhesive,
coated
fabric,
electrical
cable
construction,inRatable
gear, sealing
strips
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nitrate. Cellulose acetate is superior to cellulose nitrate in
resistance to
outdoor e+posure and to burning. %unlight has little e*ecton tmaterial. %ince there are many commercial
compositions of this material, it is advisable for a given
application to indicate the application and desired
properties, for e+ample, for general use, resistance to
heat, cold, impact, or moisture.
%ellulose acetate butyrate material is tough and has dimensional
stability.Fluctuation in dimension must be considered when articles aremade of a comCbination of this material and glass or metal.
$thyl cellulose material possesses toughness, high impact strength
at low temperatures, and excellent dimensional stability. When the
article is in combination with glass or steel, assurance must be made that
the wall thickness of the plastic is sufficient to withstand the strain
caused bytemperature changes. #ype II of this plastic is specifically
designed for low!temperature resistance. At G0DF., its impact strength is
about @E of its impact strength at normal temperatures.
ylon is a generic term for any long!chain synthetic polymeric
amide which has recurring amide groups as an intergral part of the main
polymer chain, and which is capable of being formed into a filament
whose structural elements are
oriented in the direction of the axis. ylon textile filament materials are
noted for their toughness. #he effect of extreme cold on the mechanical
properties of cords and ropes is small9 tensile strength increases and
elongation
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decreases. Woven fabrics will not be stiffened or embrittled by extreme
cold and remains soft and pliable at G@DF. #he effect of prolonged
exposure to sunlight and outdoor weather is not enough to impair practical utility.
3everal different types of nylon g plastic s are involved here atheir
properties are not identical. Impact strength is measurably decreased by
exCtreme cold but toughness and impact strength at low temperatures are
still so good that nylon plastics have been successfully used at low
temperatures. AtG@DF., the impact strength of nylon is about 00E of its
impact strength at normal temperatures. #he electrical properties ofnylon plastics are better at low temperatures than at normal
temperatures. "rolonged exposure of nylon plastics to sunshine and
weathering is not recommended.
"olyethylene and polythene materials are tough and durable. #heir
toughness is not seriously effected by low temperatures. #hese materials
remain fairly flexible at moderately low temperatures, stiffen slightly at
temperatures of G;DF. and lower, and become brittle at G>@DF. #hey
have excellent electrical properties, extremely low moisture vapor
transfer 8ualities, resist solvents and strong acids, and have other
desirable 8ualities such as nontoxicity.
"olytetrafluoroethylene has potential utility owing to its excellent
thermal stability, resistance to corrosive reagents, and low dielectric
loss.It is not embrittled by extremely low temperatures.
Films can be flexed at temperatures as low as G/@
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"olyvinyl acetal material provides a tough impact!resistant
adhesive layer for safety glass over a wide range of temperatures down
to about G@DF., is stable to light and heat, relatively insensitive to
moisture, and has goodadhesive 8ualities. It is an excellent thermoplastic adhesive for leather,
rubber, paper, wood, canvas, laminated cellophane, and glass.
It is also excellent for coating fabrics for raincoats, water!repellent
garments, tentage, food and clothing bags, etc.
"olyvinyl chloride compositions are noteworthy for their heat
resistance,exceptional toughness, and ability to withstand continuedexposure to maximum temperature differences. 3ome of these
compounds have a low!temperature brittleness approaching G@D and
G0DF. when subjected to bending. oweve such material if subjected to
sudden shock would fail at higher temperatures,possibly approaching
G;DF.
:inylidene chloride material is tough, resistant to chemicals and
prolonged
immersion in water, nonflammable, and useful over a wide range of
temperatures.