21st Conf erence on Our World in 'Concrete & Structures: 2.6· 28 August 1996, Sill8apore Pore Size Distribution of Mortar in Near Surface Concrete Its Measurement and Delineation with Carbonation S K Roy, National University of Singapore, Singapore H El-Sayad, Cairo University,-Egypt I G Shaaban, Zagzin University, Egypt D 0 Northwood, University of Windsor, Canada K B Poh, Public Works Department, Singapore ABSTRACf Ingress of deleterious agents from the environment causes deterioration of concrete and loss of its durability. Since the ingress takes place through the surface, characteristics of the near surface concrete has become an important issue in recent years. The permeation characteristics of near surface concrete are greatly responsible for concrete dutability. Tests available for assessment of permeation characteristics such as Initial Surface Absorption, Figg Permeation and Covercrete Absorption arc discussed in the introductory part of this paper. The pore size distribution of the mortar in the near surface concrete is considered an important parameter governing the durability of the concrete. Simultaneous measurement of pore size distribution by mercury porosimetry and carbonation-rate by phenolphthalein test was made on samples exposed outside in the tropical marine environment of Singapore. The carbonation rate is then delineated with pore size distribution. Results of this pore size distribution and carbonation rate measurements in near surface aortars of several concretes are reported in this paper.
Transcript
21st Conference on Our World in Concrete amp Structures 26middot 28 August 1996 Sill8apore
Pore Size Distribution of Mortar in Near Surface Concrete Its Measurement and Delineation with Carbonation
S K Roy National University of Singapore Singapore H El-Sayad Cairo University-Egypt
I G Shaaban Zagzin University Egypt D 0 Northwood University of Windsor Canada K B Poh Public Works Department Singapore
ABSTRACf
Ingress of deleterious agents from the environment causes deterioration ofconcrete and loss of its durability Since the ingress takes place through the surface characteristics of the near surface concrete has become an important issue in recent years The permeation characteristics of near surface concrete are greatly responsible for concrete dutability Tests available for assessment of permeation characteristics such as Initial Surface Absorption Figg Permeation and Covercrete Absorption arc discussed in the introductory part of this paper The pore size distribution of the mortar in the near surface concrete is considered an important parameter governing the durability of the concrete Simultaneous measurement of pore size distribution by mercury porosimetry and carbonation-rate by phenolphthalein test was made on samples exposed outside in the tropical marine environment of Singapore The carbonation rate is then delineated with pore size distribution Results of this pore size distribution and carbonation rate measurements in near surface aortars ofseveral concretes are reported in this paper
10 INTRODUCTION
11 GENERAL
The deterioration of concrete usually involves movement of aggressive gases andor liquids from the surrounding environment into concrete followed by physical andlor chemical actions within its internal structure possibly leading to irreversible damage (Basheer et al 1993) Hence the surface and near surf~ce permeation characteristics rather than the mechanical properties are the important factors for concrete durability
The permeatH3n characteristics can be assessed using tests such as Initial Surface Absorption (ISA T) (Levitt 1969) Figg Permeation Methods (Figg 1972) and Cover concrete (Covercrete) Absorption test (CAT) (Ohir 1987)
Dhir et al (1989) showed that the potential depth of carbonation may be predicted from the Figg Air Index Moreover Dhir et al (1991) demonstrated that even mechanical properties such as the abrasion resistance of concrete correlated to the ISAT middotresults as both tests assess the quality of cover concrete
12 INITIAL SURFACE AI3S0RPTION TEST (IS AT)
ISAT was developed by Levitt (1969) as a quality control test for precast concrete tiles and kerbs It is described in detail in BS 1881 Part 5 1970 The revised version issued in 1983 (BS 1881 Part 122) has only minor changes
The ISA T apparatus is shown in figure I It consists of a U-tube type structure with an opening at the bottom in the form of a circular cap (diameter 90mm) with surface area greater than 5000 mm2bull The cap is capable of being sealed to the concrete surface to withstand a small pressure of 202 Nm1 (200mm head of water) by means of a clamp Chan (1986) modified the ISAT apparatus to make it more compact portable and easier to use Ohir et a (1987) used a model air craft engine elastic similar to an elastic band to provide better seal for the cap on the concrete surface The ISAT cap was further modified by Byars (1991) by introducing a slope to the roof in order to flush the air bubbles rapidly prior to testing One of the open ends of the U-tube is fitted with a reservoir which can be isolated from the system The other is attached to a calibrated capillary tube supported horizontally by a frame 200mm above the concrete surface The system is filled with water expelling any air bubbles The amount of water absorbed by the concrete surface per minute (ISA value) is measured at 10 3060 and 120 minutes
13 FIGG AIR PERMEATION INDEX (API)
Figg (1973) described the development of a test for air and water permeability of the cover concrete Cather et al (1984) modified the test technique in order to make it more applicable on site Dhir et al (1987) reported a problem in using the Figg water test due to possible inconsistency in the manual injection
of wate~ in concrete It was concluded that the test is unreliable
In the same publication the Figg Air Test was modified to give more repeatable results
In the API test apparatus a hole of 0 30 x 50 mm is drilled in the concrete surface A polythene disc bridge and silicon rubber are inserted to block off the top 20 mm of the hole During the test air is evacuated from the test cavity using a hypodermic needle connected to a hand vacuum pump (55 KPA below atmospheric pressure) The elapsed time for the pressure to
increase from 55 to 45 KPA below atmospheric pressure is considered an index of the air permeability of concrete
14 COYER CONCRETE COYERCRETE ABSORPTION TEST (CAT)
Ohir et al (1987) developed CAT in order to test the first 50 mm of the concrete cover to the reinforcement A hole similar to that drilled in the API is used A basic ISA T set-up is used but with a 13 mm internal diameter cap An inlet tube located inside the sealed hole is used to supply water to the hole as shown in figure 2 The procedure for CAT is similar to that for ISAT
15 APPLICATION OF THE PREMEATION TESTS IN SITU
The effect of the moisture content of concrete on the permeation test results is considerable For example a concrete sample with a strength middotof 30 Nmm 2 when tested after water soaking for 2 days gave an ISA value of 025mllm2s This is classified as low sorptivity concrete in accordance with the concrete society recommendations (1986)
If however the same sample is tested after a long period of air drying the measured ISA value was 50 mllm2s which is classified as high sorptivity (Ohir et al 1987) Despite this there is no standard preconditioning method which is suitable for both laboratory and in situ applications BS 1881 parts 1970 recommends two days air drying as a preconditioning method for
in situ concrete The obvious variations in exposure to sun wind and rain makes this approach unviableOhir et al (1993) presented a technique for preconditioning concrete prior to the application of ISA T The technique is based on drying the concrete surface by withdrawing moisture using a vacuum pump The vacuum is applied to a modified ISA T cap containing silica gel granules which tum from pink to blue as the drying process proceeds After drying is completed the ISAT may be carried out in situ by fixing the cap to the structural member using suction cups The measurements must be taken within 10 minutes from the release of vacuum pilot In situ trials have shown that the test procedures reproducible results is rwn destructive and simpleto operate
Shaaban and EI Sayad (1994) applied the same vacuum technique to precondition samples for the API and CAT tests It was reported that applyin~the vacuum directly to the hypodermic needle or the cap in Art and CAT respectively leads to better reproducibility in the results However the vacuum technique was
214
I
lind to sensit h API ampTth81 ISAT Ie auth( buted t le natUl e fonne which
int drill lies II rete lereror
he 1eity 01 vity 111 tthe IT ments
Theq If near conere rs wid th( lded laquo e in c with )rk) ar
mouldl en sur r conci urtaces e Size
tributi f mort near ~ concrmiddot Id the carL ~ ~ -un UCpL- - 1lt 11lUltl-f 111 UI nft_iu~ )f~AC
of JS con expose two y( the tl pnmiddot bullbull _bullbullbull)en of ____~- ore afc ~d in tt r
RIME DETJ
Coner els of v grades ast and water ~ mys f leiS we - expOSf ~ -- ~ years two si iingap( nely (iftop at ational
UPtu~1ti v~ ~nO~n~r( -J~~Awhir~ l inlantl ~ - ~~~tn Anti
(ii lSt Coa which )rderin e ocear co p8l1el~ lered 1 5 8 and 11
posed t as( em I where Isnum 346bull 12 and ire exp( the Nt top
After ars eXI the par re retur laoOl imu lITe L auoll umiddotmiddotr c -uel1gtur-j ~ ruU me
)Ulded Lice al e unn d SUr The pnolnhc~l test ed to __ Tine the middotmiddotJnation
de he pher alein (e ~ simpl 8l110ng Ite ilable I SUring lation It als(
tmedia cation an lITgt n of ttul life mainin jsting sLs Phei lalein iourless
ac n - e mOrc- --1lcnlur )le WllC L- h is a- middot - ~
va the raJ 84 to at is le conlt ~Il__ bullbullbull _ Trill r __hth][ci t)]rlrl ___ bull nlll _
110 ethy o Th on is sp )nto atmiddot broken rface as been d of cit loose ( s The
ffii nent is out im ely aftc roken ha 1 expo~ (aline f conc rning Irple c 11 no ron ocr lrbonat s t8lCen
Iace an the dep Ie carb surfaet can be
w se loea Jrface ( ~ and tl thod pr or indicati he extc lrbonat
iIr pieelt extrac _m the t ions of e2 crete p porc si ibution rement a ry pOSt r (Mic tics Po 9320) C( - - (ne pc- -Illtllt ---- Ulll ar--l1atcIY J
0 m It s be cmp that it 1ly the Ih__ _ used fl_ lorosil
poresiz lsures I IUme d tion oj
materi mcrcul sion or tOn Ivp P etry i~ d on ry lal erning ~netrall small I I IllS la e ease ( welting quid Ii cury a ndrical is exp by the
yl~ChhllJ l ~ 111 tOII-~~~
VI d valent er of th ded pOI y ___ueen~_ _ mercl~
angl mtact t 1 the n and t pore
P sure a h a gi increm of ury inl nto the ystem
volum mercur penetT pores
a que chization e pres~ )ores a Iy c cal he above m cons a speci leI hich rr bull best re pores al mate HoweyS use i rally at f as the cal me-) treathmiddot
I herwis d be a I lInplex m
~~ LeOlUli-- iIllIplC (- - -Slec IS r- i )Ken m
mailer and th~d in ar for at4 hoUi Nhpn l( __ he ~nec_bull$Ihen n~ ~ Ihl III--~ v tpr In Iv _
I into on epressl s As n is nor Ilg t mater will n ~trate i pores luI Iydrostc ssure Jroperti se a me urface ontact solid lme thlnum Ski area 81 1 radius vature Ie at a pressl n il in pre In the y shift al8l1ce en ~UUUIC lei 11I1U oufmiddot ~Fcu Cltu~g hc fUOIUS ~f C -va~ure -J
he mer )ntactir solid tc c me sma Jlhen f adius i5c to that t rAe entra_~ ercurv L_ il~ vnlnr~
v the por JS after ating t1 pIe pr is a 10 fo[( nercur he POf le sam I he olumecury pe 19 the p 15 measc irectly functil iJpied r As tt ure inc mercu
If-middotmiddot ~middot Into snmiddot_ I1 -- -nd sma- middotes ihr 1es are 1 ier I high e 10 en I intru~ mercur ce
f _ bullbull I1cinn c _ bullbull1frCl1ry _ ~fn rrnl _ thf rn_oI ic
releasee rude th ury frol lores
The tensio e merCI ) taken 85 nd the cing co ngle is ed to t 0deg
lYYjJ compie the pro le tollo u-amet( Nere de ed
i) rusion ii) re area
ned ian iametel werage liamete
v) It and t lsily
IIn Il Its see prese the n for T___ nore d__J
~O )ULTS inset
Figu shows JIIS oft iandia for JOmmc Ulooo a Jlooo Sl llgun nows espect botilths ofb unmOl ayers 2
15
IJmm
Fi lt)2 Schematic arrangement of CAT
216
median pore diameter m) 60
-~
50
40
30
20
10
0 2 s 4 5 10 118 9
Fig3(a) Median pore diameter vs concrete samples (moulded and unmoulded layers)
Fig3(b) Carbonation depth vs concrete samples (moulded and unmoulded l ayers )
217
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
ltlthF ~ aoE t ft ~tfq4Y ~ 1u npjll Tt- rove Its t he I Met for termg tf ir
erm lity oncr Ma ne 0 mcn Iese Yo 3- 0 1- - gtp - 245 - -14
han ~ I gn I ifica and elop It of aratl ft leasl lent n sit efme n pi rties cone lten -~epo JniYI bull Y 01- Idee 21 6
C RA tHo PC 1reur orsir - y of Ient-d later and oci con on j )rs Istru n an
E dmg enal 017 A p n 1-2middot5 1993
)hir lt vlett C Ch Y) Nea Jrfa( ecteri of ( rete ssmand lopli of j tu st rr )ds - igaz lfC te R Uch 139 14
n 1vbull-o lU
)hif K vlett C Chi YN Nea Jrfac clii_cterliii -otc- rete 1CI~dictL middot)fCliiinatkri Sistflik ~fU5~7np~ vi rnnclP I)purh iJi ill rtv lifO pp 11~_i4l
989
-)11[[ - K viet -C CIl Y Nea Jrfa(
S lure 01 2 p I 28
1 K ina 1 L~ Ila 1 ami D ars u~- _nnrl~~lino- jIll (v ~r~t~ l fprlT-~jlln t~~~~O t=J~ I
nitia face orpt M ine ( mcr ~ese V c 4 0 1( lp 1 118 3
_iQI _ tv ____ octs __ leas air _ _ wat_~rm __ litv _
c rete Igaz )f C etelarer )1 210 8 pi
~ 13- 197
1 M ~on_c_~ruc _ testi c If _ _1 _ thl )
urfal )5011 I me P edir )f S) JsiUl Noln
[ucti resti gtf C ete Tirr Ins e of i rng1f~~-~S~ L(- ~)n p- )-jO tt07
haa IG EI-~ d H rece ioni 11 sit ocre erm n te ( F Inte iona
I U1lc middot~middot~HtI rH t t lit u luVlJr~ lounc~-- f VOl
air( _~ypt 116 180 Jalll 199
Nasi nW Not I a II lct 01 erm
3 L 5-] 921
10 INTRODUCTION
11 GENERAL
The deterioration of concrete usually involves movement of aggressive gases andor liquids from the surrounding environment into concrete followed by physical andlor chemical actions within its internal structure possibly leading to irreversible damage (Basheer et al 1993) Hence the surface and near surf~ce permeation characteristics rather than the mechanical properties are the important factors for concrete durability
The permeatH3n characteristics can be assessed using tests such as Initial Surface Absorption (ISA T) (Levitt 1969) Figg Permeation Methods (Figg 1972) and Cover concrete (Covercrete) Absorption test (CAT) (Ohir 1987)
Dhir et al (1989) showed that the potential depth of carbonation may be predicted from the Figg Air Index Moreover Dhir et al (1991) demonstrated that even mechanical properties such as the abrasion resistance of concrete correlated to the ISAT middotresults as both tests assess the quality of cover concrete
12 INITIAL SURFACE AI3S0RPTION TEST (IS AT)
ISAT was developed by Levitt (1969) as a quality control test for precast concrete tiles and kerbs It is described in detail in BS 1881 Part 5 1970 The revised version issued in 1983 (BS 1881 Part 122) has only minor changes
The ISA T apparatus is shown in figure I It consists of a U-tube type structure with an opening at the bottom in the form of a circular cap (diameter 90mm) with surface area greater than 5000 mm2bull The cap is capable of being sealed to the concrete surface to withstand a small pressure of 202 Nm1 (200mm head of water) by means of a clamp Chan (1986) modified the ISAT apparatus to make it more compact portable and easier to use Ohir et a (1987) used a model air craft engine elastic similar to an elastic band to provide better seal for the cap on the concrete surface The ISAT cap was further modified by Byars (1991) by introducing a slope to the roof in order to flush the air bubbles rapidly prior to testing One of the open ends of the U-tube is fitted with a reservoir which can be isolated from the system The other is attached to a calibrated capillary tube supported horizontally by a frame 200mm above the concrete surface The system is filled with water expelling any air bubbles The amount of water absorbed by the concrete surface per minute (ISA value) is measured at 10 3060 and 120 minutes
13 FIGG AIR PERMEATION INDEX (API)
Figg (1973) described the development of a test for air and water permeability of the cover concrete Cather et al (1984) modified the test technique in order to make it more applicable on site Dhir et al (1987) reported a problem in using the Figg water test due to possible inconsistency in the manual injection
of wate~ in concrete It was concluded that the test is unreliable
In the same publication the Figg Air Test was modified to give more repeatable results
In the API test apparatus a hole of 0 30 x 50 mm is drilled in the concrete surface A polythene disc bridge and silicon rubber are inserted to block off the top 20 mm of the hole During the test air is evacuated from the test cavity using a hypodermic needle connected to a hand vacuum pump (55 KPA below atmospheric pressure) The elapsed time for the pressure to
increase from 55 to 45 KPA below atmospheric pressure is considered an index of the air permeability of concrete
14 COYER CONCRETE COYERCRETE ABSORPTION TEST (CAT)
Ohir et al (1987) developed CAT in order to test the first 50 mm of the concrete cover to the reinforcement A hole similar to that drilled in the API is used A basic ISA T set-up is used but with a 13 mm internal diameter cap An inlet tube located inside the sealed hole is used to supply water to the hole as shown in figure 2 The procedure for CAT is similar to that for ISAT
15 APPLICATION OF THE PREMEATION TESTS IN SITU
The effect of the moisture content of concrete on the permeation test results is considerable For example a concrete sample with a strength middotof 30 Nmm 2 when tested after water soaking for 2 days gave an ISA value of 025mllm2s This is classified as low sorptivity concrete in accordance with the concrete society recommendations (1986)
If however the same sample is tested after a long period of air drying the measured ISA value was 50 mllm2s which is classified as high sorptivity (Ohir et al 1987) Despite this there is no standard preconditioning method which is suitable for both laboratory and in situ applications BS 1881 parts 1970 recommends two days air drying as a preconditioning method for
in situ concrete The obvious variations in exposure to sun wind and rain makes this approach unviableOhir et al (1993) presented a technique for preconditioning concrete prior to the application of ISA T The technique is based on drying the concrete surface by withdrawing moisture using a vacuum pump The vacuum is applied to a modified ISA T cap containing silica gel granules which tum from pink to blue as the drying process proceeds After drying is completed the ISAT may be carried out in situ by fixing the cap to the structural member using suction cups The measurements must be taken within 10 minutes from the release of vacuum pilot In situ trials have shown that the test procedures reproducible results is rwn destructive and simpleto operate
Shaaban and EI Sayad (1994) applied the same vacuum technique to precondition samples for the API and CAT tests It was reported that applyin~the vacuum directly to the hypodermic needle or the cap in Art and CAT respectively leads to better reproducibility in the results However the vacuum technique was
214
I
lind to sensit h API ampTth81 ISAT Ie auth( buted t le natUl e fonne which
int drill lies II rete lereror
he 1eity 01 vity 111 tthe IT ments
Theq If near conere rs wid th( lded laquo e in c with )rk) ar
mouldl en sur r conci urtaces e Size
tributi f mort near ~ concrmiddot Id the carL ~ ~ -un UCpL- - 1lt 11lUltl-f 111 UI nft_iu~ )f~AC
of JS con expose two y( the tl pnmiddot bullbull _bullbullbull)en of ____~- ore afc ~d in tt r
RIME DETJ
Coner els of v grades ast and water ~ mys f leiS we - expOSf ~ -- ~ years two si iingap( nely (iftop at ational
UPtu~1ti v~ ~nO~n~r( -J~~Awhir~ l inlantl ~ - ~~~tn Anti
(ii lSt Coa which )rderin e ocear co p8l1el~ lered 1 5 8 and 11
posed t as( em I where Isnum 346bull 12 and ire exp( the Nt top
After ars eXI the par re retur laoOl imu lITe L auoll umiddotmiddotr c -uel1gtur-j ~ ruU me
)Ulded Lice al e unn d SUr The pnolnhc~l test ed to __ Tine the middotmiddotJnation
de he pher alein (e ~ simpl 8l110ng Ite ilable I SUring lation It als(
tmedia cation an lITgt n of ttul life mainin jsting sLs Phei lalein iourless
ac n - e mOrc- --1lcnlur )le WllC L- h is a- middot - ~
va the raJ 84 to at is le conlt ~Il__ bullbullbull _ Trill r __hth][ci t)]rlrl ___ bull nlll _
110 ethy o Th on is sp )nto atmiddot broken rface as been d of cit loose ( s The
ffii nent is out im ely aftc roken ha 1 expo~ (aline f conc rning Irple c 11 no ron ocr lrbonat s t8lCen
Iace an the dep Ie carb surfaet can be
w se loea Jrface ( ~ and tl thod pr or indicati he extc lrbonat
iIr pieelt extrac _m the t ions of e2 crete p porc si ibution rement a ry pOSt r (Mic tics Po 9320) C( - - (ne pc- -Illtllt ---- Ulll ar--l1atcIY J
0 m It s be cmp that it 1ly the Ih__ _ used fl_ lorosil
poresiz lsures I IUme d tion oj
materi mcrcul sion or tOn Ivp P etry i~ d on ry lal erning ~netrall small I I IllS la e ease ( welting quid Ii cury a ndrical is exp by the
yl~ChhllJ l ~ 111 tOII-~~~
VI d valent er of th ded pOI y ___ueen~_ _ mercl~
angl mtact t 1 the n and t pore
P sure a h a gi increm of ury inl nto the ystem
volum mercur penetT pores
a que chization e pres~ )ores a Iy c cal he above m cons a speci leI hich rr bull best re pores al mate HoweyS use i rally at f as the cal me-) treathmiddot
I herwis d be a I lInplex m
~~ LeOlUli-- iIllIplC (- - -Slec IS r- i )Ken m
mailer and th~d in ar for at4 hoUi Nhpn l( __ he ~nec_bull$Ihen n~ ~ Ihl III--~ v tpr In Iv _
I into on epressl s As n is nor Ilg t mater will n ~trate i pores luI Iydrostc ssure Jroperti se a me urface ontact solid lme thlnum Ski area 81 1 radius vature Ie at a pressl n il in pre In the y shift al8l1ce en ~UUUIC lei 11I1U oufmiddot ~Fcu Cltu~g hc fUOIUS ~f C -va~ure -J
he mer )ntactir solid tc c me sma Jlhen f adius i5c to that t rAe entra_~ ercurv L_ il~ vnlnr~
v the por JS after ating t1 pIe pr is a 10 fo[( nercur he POf le sam I he olumecury pe 19 the p 15 measc irectly functil iJpied r As tt ure inc mercu
If-middotmiddot ~middot Into snmiddot_ I1 -- -nd sma- middotes ihr 1es are 1 ier I high e 10 en I intru~ mercur ce
f _ bullbull I1cinn c _ bullbull1frCl1ry _ ~fn rrnl _ thf rn_oI ic
releasee rude th ury frol lores
The tensio e merCI ) taken 85 nd the cing co ngle is ed to t 0deg
lYYjJ compie the pro le tollo u-amet( Nere de ed
i) rusion ii) re area
ned ian iametel werage liamete
v) It and t lsily
IIn Il Its see prese the n for T___ nore d__J
~O )ULTS inset
Figu shows JIIS oft iandia for JOmmc Ulooo a Jlooo Sl llgun nows espect botilths ofb unmOl ayers 2
15
IJmm
Fi lt)2 Schematic arrangement of CAT
216
median pore diameter m) 60
-~
50
40
30
20
10
0 2 s 4 5 10 118 9
Fig3(a) Median pore diameter vs concrete samples (moulded and unmoulded layers)
Fig3(b) Carbonation depth vs concrete samples (moulded and unmoulded l ayers )
217
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
ltlthF ~ aoE t ft ~tfq4Y ~ 1u npjll Tt- rove Its t he I Met for termg tf ir
erm lity oncr Ma ne 0 mcn Iese Yo 3- 0 1- - gtp - 245 - -14
han ~ I gn I ifica and elop It of aratl ft leasl lent n sit efme n pi rties cone lten -~epo JniYI bull Y 01- Idee 21 6
C RA tHo PC 1reur orsir - y of Ient-d later and oci con on j )rs Istru n an
E dmg enal 017 A p n 1-2middot5 1993
)hir lt vlett C Ch Y) Nea Jrfa( ecteri of ( rete ssmand lopli of j tu st rr )ds - igaz lfC te R Uch 139 14
n 1vbull-o lU
)hif K vlett C Chi YN Nea Jrfac clii_cterliii -otc- rete 1CI~dictL middot)fCliiinatkri Sistflik ~fU5~7np~ vi rnnclP I)purh iJi ill rtv lifO pp 11~_i4l
989
-)11[[ - K viet -C CIl Y Nea Jrfa(
S lure 01 2 p I 28
1 K ina 1 L~ Ila 1 ami D ars u~- _nnrl~~lino- jIll (v ~r~t~ l fprlT-~jlln t~~~~O t=J~ I
nitia face orpt M ine ( mcr ~ese V c 4 0 1( lp 1 118 3
_iQI _ tv ____ octs __ leas air _ _ wat_~rm __ litv _
c rete Igaz )f C etelarer )1 210 8 pi
~ 13- 197
1 M ~on_c_~ruc _ testi c If _ _1 _ thl )
urfal )5011 I me P edir )f S) JsiUl Noln
[ucti resti gtf C ete Tirr Ins e of i rng1f~~-~S~ L(- ~)n p- )-jO tt07
haa IG EI-~ d H rece ioni 11 sit ocre erm n te ( F Inte iona
I U1lc middot~middot~HtI rH t t lit u luVlJr~ lounc~-- f VOl
air( _~ypt 116 180 Jalll 199
Nasi nW Not I a II lct 01 erm
3 L 5-] 921
I
lind to sensit h API ampTth81 ISAT Ie auth( buted t le natUl e fonne which
int drill lies II rete lereror
he 1eity 01 vity 111 tthe IT ments
Theq If near conere rs wid th( lded laquo e in c with )rk) ar
mouldl en sur r conci urtaces e Size
tributi f mort near ~ concrmiddot Id the carL ~ ~ -un UCpL- - 1lt 11lUltl-f 111 UI nft_iu~ )f~AC
of JS con expose two y( the tl pnmiddot bullbull _bullbullbull)en of ____~- ore afc ~d in tt r
RIME DETJ
Coner els of v grades ast and water ~ mys f leiS we - expOSf ~ -- ~ years two si iingap( nely (iftop at ational
UPtu~1ti v~ ~nO~n~r( -J~~Awhir~ l inlantl ~ - ~~~tn Anti
(ii lSt Coa which )rderin e ocear co p8l1el~ lered 1 5 8 and 11
posed t as( em I where Isnum 346bull 12 and ire exp( the Nt top
After ars eXI the par re retur laoOl imu lITe L auoll umiddotmiddotr c -uel1gtur-j ~ ruU me
)Ulded Lice al e unn d SUr The pnolnhc~l test ed to __ Tine the middotmiddotJnation
de he pher alein (e ~ simpl 8l110ng Ite ilable I SUring lation It als(
tmedia cation an lITgt n of ttul life mainin jsting sLs Phei lalein iourless
ac n - e mOrc- --1lcnlur )le WllC L- h is a- middot - ~
va the raJ 84 to at is le conlt ~Il__ bullbullbull _ Trill r __hth][ci t)]rlrl ___ bull nlll _
110 ethy o Th on is sp )nto atmiddot broken rface as been d of cit loose ( s The
ffii nent is out im ely aftc roken ha 1 expo~ (aline f conc rning Irple c 11 no ron ocr lrbonat s t8lCen
Iace an the dep Ie carb surfaet can be
w se loea Jrface ( ~ and tl thod pr or indicati he extc lrbonat
iIr pieelt extrac _m the t ions of e2 crete p porc si ibution rement a ry pOSt r (Mic tics Po 9320) C( - - (ne pc- -Illtllt ---- Ulll ar--l1atcIY J
0 m It s be cmp that it 1ly the Ih__ _ used fl_ lorosil
poresiz lsures I IUme d tion oj
materi mcrcul sion or tOn Ivp P etry i~ d on ry lal erning ~netrall small I I IllS la e ease ( welting quid Ii cury a ndrical is exp by the
yl~ChhllJ l ~ 111 tOII-~~~
VI d valent er of th ded pOI y ___ueen~_ _ mercl~
angl mtact t 1 the n and t pore
P sure a h a gi increm of ury inl nto the ystem
volum mercur penetT pores
a que chization e pres~ )ores a Iy c cal he above m cons a speci leI hich rr bull best re pores al mate HoweyS use i rally at f as the cal me-) treathmiddot
I herwis d be a I lInplex m
~~ LeOlUli-- iIllIplC (- - -Slec IS r- i )Ken m
mailer and th~d in ar for at4 hoUi Nhpn l( __ he ~nec_bull$Ihen n~ ~ Ihl III--~ v tpr In Iv _
I into on epressl s As n is nor Ilg t mater will n ~trate i pores luI Iydrostc ssure Jroperti se a me urface ontact solid lme thlnum Ski area 81 1 radius vature Ie at a pressl n il in pre In the y shift al8l1ce en ~UUUIC lei 11I1U oufmiddot ~Fcu Cltu~g hc fUOIUS ~f C -va~ure -J
he mer )ntactir solid tc c me sma Jlhen f adius i5c to that t rAe entra_~ ercurv L_ il~ vnlnr~
v the por JS after ating t1 pIe pr is a 10 fo[( nercur he POf le sam I he olumecury pe 19 the p 15 measc irectly functil iJpied r As tt ure inc mercu
If-middotmiddot ~middot Into snmiddot_ I1 -- -nd sma- middotes ihr 1es are 1 ier I high e 10 en I intru~ mercur ce
f _ bullbull I1cinn c _ bullbull1frCl1ry _ ~fn rrnl _ thf rn_oI ic
releasee rude th ury frol lores
The tensio e merCI ) taken 85 nd the cing co ngle is ed to t 0deg
lYYjJ compie the pro le tollo u-amet( Nere de ed
i) rusion ii) re area
ned ian iametel werage liamete
v) It and t lsily
IIn Il Its see prese the n for T___ nore d__J
~O )ULTS inset
Figu shows JIIS oft iandia for JOmmc Ulooo a Jlooo Sl llgun nows espect botilths ofb unmOl ayers 2
15
IJmm
Fi lt)2 Schematic arrangement of CAT
216
median pore diameter m) 60
-~
50
40
30
20
10
0 2 s 4 5 10 118 9
Fig3(a) Median pore diameter vs concrete samples (moulded and unmoulded layers)
Fig3(b) Carbonation depth vs concrete samples (moulded and unmoulded l ayers )
217
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
Fig3(b) Carbonation depth vs concrete samples (moulded and unmoulded l ayers )
217
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
Fig3(b) Carbonation depth vs concrete samples (moulded and unmoulded l ayers )
217
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
ltlthF ~ aoE t ft ~tfq4Y ~ 1u npjll Tt- rove Its t he I Met for termg tf ir
erm lity oncr Ma ne 0 mcn Iese Yo 3- 0 1- - gtp - 245 - -14
han ~ I gn I ifica and elop It of aratl ft leasl lent n sit efme n pi rties cone lten -~epo JniYI bull Y 01- Idee 21 6
C RA tHo PC 1reur orsir - y of Ient-d later and oci con on j )rs Istru n an
E dmg enal 017 A p n 1-2middot5 1993
)hir lt vlett C Ch Y) Nea Jrfa( ecteri of ( rete ssmand lopli of j tu st rr )ds - igaz lfC te R Uch 139 14
n 1vbull-o lU
)hif K vlett C Chi YN Nea Jrfac clii_cterliii -otc- rete 1CI~dictL middot)fCliiinatkri Sistflik ~fU5~7np~ vi rnnclP I)purh iJi ill rtv lifO pp 11~_i4l
989
-)11[[ - K viet -C CIl Y Nea Jrfa(
S lure 01 2 p I 28
1 K ina 1 L~ Ila 1 ami D ars u~- _nnrl~~lino- jIll (v ~r~t~ l fprlT-~jlln t~~~~O t=J~ I
nitia face orpt M ine ( mcr ~ese V c 4 0 1( lp 1 118 3
_iQI _ tv ____ octs __ leas air _ _ wat_~rm __ litv _
c rete Igaz )f C etelarer )1 210 8 pi
~ 13- 197
1 M ~on_c_~ruc _ testi c If _ _1 _ thl )
urfal )5011 I me P edir )f S) JsiUl Noln
[ucti resti gtf C ete Tirr Ins e of i rng1f~~-~S~ L(- ~)n p- )-jO tt07
haa IG EI-~ d H rece ioni 11 sit ocre erm n te ( F Inte iona
I U1lc middot~middot~HtI rH t t lit u luVlJr~ lounc~-- f VOl
air( _~ypt 116 180 Jalll 199
Nasi nW Not I a II lct 01 erm
3 L 5-] 921
lr 1 the _- sam i th edia ore I letel Ir th UI uldlt lffipl with ~er ( )nal Jepl re gl r Ian t Olf _nou san s (sn ~r ca laUCl ~ pm ~ b~ rl~_J_lt ihL _ inmiddottl_ Cvn fi c _ cfl bullbullbullbull ll th~ ur _)llde_
rc 1S laq _ arbc on C IS w QUnl lye I r ore s as WI Figu (a) i n be 1 tha me par
