KHOA HOC C O N C N C H t
SLr DUIVE IMd HiNH s d DE aV BAD KHA l\lAlVG H A P T H I J I D M CI CIJA VAT L l f U X I IMAMG VA
PHIJ BIA KHOAIXIG
Trfn van QuSn' T6MTAT
An mon diep la mOt Irong nhung van dd lon anil hudng den do bdn cda kdt cau be tdng cdt thep. Kha nang hip Uiu ion CI la itioni: «<• chinh cho nJi ro an mdn thep oia be tong cdt diep uong mdi truong dung dich clorua. Du vay. do bdn cua kdl cau be long cdt diep co did dupe danh gia bang viec du doan kha nang hap Uiu lon CI- oia bd tdng C6t diep. Dd danh gia chinh xac kha nang bi-ip thu ion CI- ciia bd tong. nhidu nid hinh sd da duflc phat uidn tuy nhien da sd cac md hinh sd nay la mo hinh thuc nghidm phu thupc manh me vail ket qua Uii nghi(TO. .Mo hinh dja hda hpc cd the du dean kha nang h^p thp ion CI- ciia cac loai bd tdng khac nhau ma khong can Udn hanh thi nghidm md hinh vat K. Mo hinh dia hda dupe md ta ngan gpn trong phan dau cua bai bao. Kh.-i nang hap thu ion CI- cua CK.M I (xi mang Portland). CEM I + tio bay (FA) + mudi silic (SI-") va xi mang Portland bdn sunphat (SRPC) trong mdi trudng dung dich clorua 5 g.l' va 20 g.l' so dupe dudoan Iheo nid hinh dja hda. Dpng luc hpc ciia kha nang hap thu ion CI- cQng dupe thao luan.
TH khda: lie tong .\i mang. kha nang ha'p thu ion CI. mo hinh dia boa. xi niing PoiHand, xi mang ben sunp/iat
I.IWBAU
Co chd cua kha nang heip thu ion CI- aia vat lidu xi mang da dupe thao l u ^ nhieu tai cac nghien ciiu U-dn thd gioi vi kha nang hap thy ion CI- anh hudng ddn cau tnic ciia be tdng va hl^u suat sir dung lau dai cua kdt Ciiu bd long cdt thep. Su an mon cua be tdng cdt thdp la ydu td gay xudng cap chu ydu cua cac cau true bd tting tidp xiic vdi mdi truong xam thuc nhu khu mudi lam lan bang gia. mdi trudng bidn.
An mdn cd did xay ra khi cd oxy va hoi am lai giao di^n tiep xuc cua bd tdng va cdt thep. sau khi CIC ion clorua xam nhap vao bd tdng. ndp can thdp va lam giam pH ciia dung dich 16 rdng gay ra su pha va iiuuig oxit thu ddng bao v^ lop tliep [1].
Do do. viix- du doan su xam nhap cua clorua vao bd tdng CO anh hudmg ddn Uidi gian bat dau va lan iniycn an mon. Dieu nay la mau chdt quan u-ong hang dau dd lluil kd kdl cau be tdng cdt thep hoat ddire hidu qua lau dai Irong cac nidi iruong xam thuc (iimic bidn. nuoc Uiai). Ihicl ke thdi gian b.io in. uoc tinh tudi tho cdn lai cua ket cau be tdng hien tar Hap thy ion 11 CO anh huong dang kd den su xam nhf!
doma trong bd tdng. Su xual hidn cua viec h.ip -^r ion il- CO thd lam giam nguy co an mon va UUi.c IM,.
rnnmi; D.ii hpc Cdng nglic tii, riLiii (]uanl\i^uu.cdu.\n
tho uoc tinh cua cac ket cau be tdng cdt thep. Hap thu ion CI- lam giam cac ion clorua hr do cd trong dung dich 16 rdng thong qua sit hinh thanh mudi Friedel CajAI,Cl,s5(OH),,„5.4H20. mudi Kuzel Ca,AI,(SOJ„Cl(OH),2.6H,6 va lien kdt vtji ma tran xi mang nhu hap thu boi be mat keo C-S-H [2]. [3].
De danh gia chinh xac kha nang hap thu ion Cl- cua be tdng. nhidu md hinh sd da dupe phat trien tuy nhien cac md hinh sd nay la cac phuong trinh thuc nghidm phu thuoc manh me vao kdt qua thi nghidm 14]. Md hinh dia hda cd the du doan kha nang hap thu ion CI- ctia be tdng sii dung cac loai xi mang khac nhau ma khong cSn thuc hien thi nghidm mo hinh vat Iy. Nhtmg loi ich cua vide s i dung md hinh dja hda de md phong dp bdn cua be tong trong mdi UTidng xam thuc nhu dung dich clorua va sunphat da dupe trinh bay trong [3]. [5]. Md hinh dia hda du doan thanh cdng kha nang h^p thu ion CI- ctia bd tong xi^mang CEM II theo tidu chuSn chau Au (NF EN 197-1) [231. Trong nghien am nay, kha nang hip ll.u ,01, CI- bao g6,n dong hoc hap thu ion cloraa va '-ha iia„g nang l,..p ,h„ ,.,„ CI- theo „6„g do ion . . - I. iMx, man, CI:MHxi mang Portland), CEM
" " " ' • " ; " ' '"'";; ^'•'•••'« mang Poraand ' - -uK«e resistanee portland
;"'";g'lungd,chclorua5gl-.va iiphat
1 U'lng ,
-•m" hinh dia hoa.
NONG NGHIEP VA PHAT TRIEN NONG THON ir y i
KHOA HOC CONG NGHE
2 . PHUONG PHAP 2.1. M6 hinh dia h6a 2.1.1. Pbuongphip tmySn chit
Trong moi tnrcmg ht tdng bao hoa, phuong trinh can bang khoi lirgng theo mot phuong co the dupe bieu di§n duoi dang sau [6], [7]:
d M , ^ _ d J , ^ (1}
dt d x **'
M,, J, va X 1 ^ lu(?t la sd Iuong moi tich luy cua chat j trong dung dich (mol.m"-^ cua vat lieu), theo mat dp d6ng chat j trong dung djch (mol.m"^.s"') va X la dp dai cua khudch tan (m). QJ nguon cua chat j (mol.m~^.s~') dupe hieu la viec cung cap hoac loai bo ch^t j khoi dung dich.
Trong moi truong r6ng, mat d6 dong ch^t j , J,, dupe mo ta bang dinh luat thu nhat cua Fick:
Dp h6 sd khuS'ch tan hifeu qua ciia chiit j (m^s'O.
2.1.2. Can bing nhidt d0ng hqc va tdc dd phin dng
Tuong lac phan ung giua cac ion c6 trong dung dich va thanh phan khoang dan den qua trinh hoa tan-k^'t tiia cua cac khoang. Qua trinh nay dupe kiem soat bkig ht so bao hoa khoang f l ^ dupe bieu dien bang cong thuc duoi day :
n . = K ; i l j(y,c,)-"' n, = l N,
1=1
Voi m la chi sd cua khoang: K^^ la hang sd can bang; C, la s6 moi ciia chat j trong 1 kg dung djch (raol. kg~^). Trang thai can bang hoac mat can
••• = '(Cl.Cs CK. ) = ± k „ A „ „ | l - n S p Trong do cac gia tri duong cua r bieu tihi su hoa tan va ngiroe lai sir ket tua vcri gia tri am; k la hang so tdc do (mol.m"^.s'); A^,s la dien tich be mat phan ung cu thi (m^.g''); n la he sd bao hoa khoang da dugc dinh nghia tai phuong trinh (phuong trinh 2). Khi phan ling tiln den trang thai can bSng, Q tien toi 1, tdc do phan ling hoa hpc co xu huong ve 0. Cac tham sd 9, n CO th^ dupe xac dinh tir cac thi nghiem, chiing thu6ng dupe lay bang mpt do thi^u phep do thi nghidm; q la sd lupng khoang duoi cac rang bupc dpng hpc. Thong sd dpng hpc ciia xi mang ngam nuoe dirpc lay tu nghien cuu cua Baur etal. [9].
bang cua chat khoang duoc kiem soat boi chi sd bao hoa khoang IS^^,:
i s „ - i o E n „ . (4) Doi voi mpt khoang bat ky, khoang nay va dung dich a trang thai can bang n^u IS^^ = 0. Khoang va dung dich trong tinh trang duoi dp bao hoa do vay khoang co the tiep tuc bi hoa tan nei'u IS^^ < 0. Cudi cung neu dung dich va khoang tren dp bao hoa tao ra viec khoang tilp tuc ket tiia neu IS^^ > 0. Cac phan ung phiic hpp giua cac ion don gian tgo thanh cac ion phuc tap dupe di§n ra trong dung dich. Cac phan ung nay dupe gia thiet luon di§n ra duoi sir can bang nhiet dpng luc hoc hay noi each khac diin ra mot each tuc thoi. Bang dinh luat can bang khdi lupng, ndng dp cua cac ion phiic hpp co th6 dupe bilu di^n thong qua phuong trinh cua cac ion don gian sau day:
C, = K-'yr'[](yiC,r. (5)
Voi Cj la nong dp moi ciia chat phuc hpp i (mol.kg"^). Y,, y, la he sd d6 hoat dpng. K^^ la hang sd can bang ciia phan ling phiic hpp ion. N^^ la sd ion phuc hpp co trong dung dich.
Cac dinh luat dong hoc TST Oy thuydt trang thai chuyen tiep) co the mo ta tdc dp hoa tan/ket tiia ciia mpt khoang chat (n) b cac gia tri pH khac nhau va hang sd dupe dua ra boi Lasaga et al [8]. Phuong trinh tdc dp phan ling duoe bidu dien thong qua phuong trinh voi cac bidn so la cac ion don gian;
n=l,..,Nq (6)
2.2. Di^u kipn bien va di^u ki§n ban ddu ciia m6 hinh
2.2.1. Thanh phan khoing thdy hda xi mang ciia cac loai xi mang su dung
Ba loai chat ket dinh dupe sir dung trong cac mo phong diroc thuc hien dua tren cac dieu kien thi nghiem cua De Weerdt et al [10] chang han nhu:
thiet ke cap phdi be tong, thanh phan hoa hpc cua xi mang. Loai chat ket dinh dau ti6n la xi mang CEM I theo tieu chuin Eurocode hoac xi mang thong thudng, loai chat ket dinh thir hai la trpn CEM I, tro bay (FA) va silica fume (SF) [10]. Chat ket dinh cuoi NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 -THANG 12/2019 59
khuech tan clorua hi«u qua ciia oa bd tdng co ^ '-"S gia m cua CKM I + FA -i- SF va duvc coi ia bang ••'•"
ciing la sir dung 100% xi mang Portland b ^ sunlat (SKIV) oia Tap doan Cdng nghidp Xj mang \iet Nam (Vicem). Dua trdn duel kd c^p phrfi va thanh phin hoa hpc. thanh phan khoang ciia xi mang thiiy hoa duoc thd hi^n trong bang 1. duoc unh nha vao phin mdm mo hinh hydral hoa GEMS III]. Hi sd
B4ng 1. Thanh ph4n khoang vjt hpc ciia id mSng thuy hda dupe tinh bing phdn mim GEMS va hf s6 khu&h X 10" (m=.s') 110) (xem bang 3). Thdng un chi net dugc md ta trong cac nghidn cihi cua Tran va nnk
|2|. 131. (51. [121-1141.
Mm.-nil lennile
I'ortlandile (ioethile Moiiosulphale Si Hvdrogamel
Hd sd khudch tan
tandoru 1 n i m u b
CJ. . S.O O H i „ , . 0 . 4 3 H - O Ca- .-SO-iOH 4.:0.5H.C Ci,.-li-,SC j , . O H | i - . 2 6 H ; 0
vie ^ . C - . lOH.O) CitOH).
FeOOH C J . A 1 . ( S 0 J ( 0 H ) . - : 6 H - 0
( j i A l . ( S i O J . s ( O H ) s , clorua hidu qua (m-'.s')
a men qua a i/a - — ^ 1
Vnlumpir-action CE.\1 I
0.1233 0.0137 0.0119 0.0119 0.0791 0.0048 0.0417 0.0000 3.87 X 10'-'
CEMI-i-FA-i-SF 0.1270 0.0425 0.0336 0.0106 0.0000 0.0048 0.0000 0.0468 3.87 X Iff"
Viccm SRPC 0.1155 0.0128 0.0280 0.0197 0.0856 0,0075 0.0000 0.0085 3 . 8 7 x 1 0 "
2.2.2. Tlianh phin hda hoc ciia dung djch thi nglii^m tham
BSng 2. Thinh p h ^ hda hpc cua dung djch thi nghi$m (moll')
Cl(g.l') 5 20
CI 0.141 0.564
Na- 0.141 0.564
Ca-- 0.027 0.027
pH 12.561 12.570 Be tdng dupe md phdng dd ngap b-ong dung djch natri clorua bao hda voi 2 g.l' Ca(0H)2 duoc
hda tan sao cho ndng dp ion clonia cd trong dung dich lin luot la 5 va 20 g.l' hojc 0.141 mol.l' v4 0.564 mol.l'. Thanh phin hda hoc ciia dung dich nay dtroc md ta trong bang 2.
2.3. Cic tham so dti li§u cua md hinh dia hda hpc
Phan irng can bang cua khoang chat va hang sd can bang ti 25°C cua phan img dirpc the hien trong bang 3.
Bing 3. Cic phuong binh can bing v4 hang sd cSn bing tuomg ling fir T - 25'C ddi v6i cic san phSm xi mang thiiy hda vi cic loai khoing thuy hda khac cd thd kft tua khi c6 mat ciia ion clorua
Mmeral
lennite - : 33H- - 1.67Ca=* 4- HSiO'" -t- 2.76H,0 Tobermorite- 0.66H* ^ 0 . 8 3 C a - + - HSiO^" ^ " l . l 6 H , 0 Ettringite -f 12H* - . :A1=- i eCa^" - 330?- -I- 3 8 H , c ' Hydrotalcite + 14H- - 4Mg;- ^ 2.A1=- - 17H,0 P o r t i a n d i t e - 2 H ' - C a - ' - 2H,0
Goethite - 3H* ^ Fe '^*
Monosulphate— 1 2 H ' -^ 4 Ca'* — 2A1^
Sl_Hydrogarnet * I I H * - . 3Ca-* - l..\i FriedeLSalt -f 12.0SH" - . 2Al'" - 4Ca KuieLSalt ^ 1 2 H " - - i.Af"" ^ 4Ca-"
TiK- do phin ung ciia cac khoanc diu\ hoa M ' iiith'iiL. ilu.
mang duTC tim va trich dan tu cac nghidn cuu tren thd gioi. Dii lieu ddng hpc cua monosulphate. ^" '"^-'•' di eimngiteva I. s l l (baogom Jennile vaTobemionle) t^i'Zel. n dutv trich xuat tir Baur el al. [9], Du luu ddng hoc- 'lyd'Otal - 2 H ; 0
" -r HSiO'- -
* - i.oscr iCI~ - USSO.
18H,0 - aH.o
LbUb 1 0
iU ill
l°g(K) 19.53 0.63 56,67 74.68 22.76 0.36 72.44
•).hl i-1.VS l.^ili
01. diji I ng bo.
du
1151. Cac thdng rong bang 4. Do thidu ' ''"a tan ciia mudi
""•""" SLhydroganiet,
^f"1>oi.Cuoiri,„g^
di^
NONG NGHIEP VA PHAT TRIEN NONG THON KY
KHOA HOC CONG NGHE
doi voi m6i khoang, toe dp phan ling cua ke-t tiia va hoa tan dupe gia thi^t la nhu nhau.
Bing 4. Cdc th6ng s6 dOng hpc phuong trinh phan ling arT-25'C: h ^ sd t6c dO k (mol.m^'sO vd dl§n
tich b^ m$t rifing ciia khodng A„B, (mVO Mineral
Jennite Tobermorite Ettringite Hydrotalcite Portlandite Goethite Monosulphate Si Hydrogamet Kuzel's salt Friedel's salt
K.
41.0 41.0 9.8 16,5 5.7
k 2.75X 10"i 2.75X Iff'' 7,08x Iff"
Tiic thdi 2,24x 10«
Ttic thai 6.76x 10'^
Tire thdi Tire thin Tiic thin
Ref [41 [41 [41 [111 [41
3 . KET QUA VA THAO L U A N
Hinh 1 cho thay lugng clorua bi hap thu boi pha ran cua be tong CEM I, CEM I + FA + SF va Vicem SRPC trong dung dich clorua nong dp clorua 5 g.l' la mOt h ^ ciia thai gian. Hinh 2 cung gioi thi^u ket quS tuong tv vcri hinh 1 trong trucmg hpp nong do clorua la 20 g.l'. Th6i gian mo phong qua trinh hap thu trong m6 hinh dia hoa la mot nam. Hinh 1 va hinh 2 cho thay trang thai on dinh da dat dugc sau vai ngay, thoi gian nay khong phu thupc vao loai chdt k^t dinh. Su hap thu ion CI- tang manh trong nhung ngdy dau ti&n cua mo phong. Sau do, su hap thu nay dgt d^n m6t trang thdi tucmg doi dn dinh. Dieu nay cung da dirac quan sat bang thuc nghiem trong cong trinh nghien ciiu cua Nguyen va nnk [16]. Su gia tang manh la do phdn ung hap fhu tren be mdt cua C- S-H, cac phdn ling nay di^n ra ngay tuc thi [2], [3], [5], [12], [13]. Hon nua, ddi voi be tong CEM I, clorua hap thu la do su hinh thanh cua muoi Kuzel, gay ra su gia tang manh ciia viec hap thu ion CI- theo thai gian. Dieu do khong dupe quan sat thay trong truong hpp ciia SRPC va be tong CEM I su dung cac phu gia nhu tro bay vd muoi silic FA + SF, cdc be tong nay khong co chua monosulphate ma lai xudt hiSn ciia Si_hydrogamet trong thdnh phdn khoang h6a ban dau. Si_hydrogamet la khoang on dinh voi hang s6 cdn bang thap hon so vdi monosulphate. Do do. muoi Kuzel khong bi ket tiia khi SRPC va CEM I + FA + SF tiep xiic voi dung dich clorua trong cac ket qua mo phong.
1"' /^
'' / ^
iM f- f
11
^--'
CE\!I SRPC - - CE\II + SF+F.A
Tlioi giBiunsiiy)
Hinh 1. Dpng hpc ciia qud trinh h^p thu ion CI- bdi bfe t6ng CEM-I, SRPC vd CEM I + FA + SF trong m6i
trudng dung dich clorua 5g.l' sau mOt ndm
i . y ,
~ on
«-^l
0
SRPC CEHI-i-SF+F.-\
10(1 ;00 300 40 Thai .^ail (ngay)
Hinh 2. Dpng hpc crua qud trinh hdp thu ion CI- bdi be tang CEM-I, SRPC vd CEM I + FA + SF trong mdi
trudng dung dich cloraa 20 g.l"^ sau mOt ndm Hinh 3 vd hinh 4 cho thay kha nang hap thu ion CI- cua ba loai be tong trong dung dich clorua 5 g.l"' va 20 g.l"' sau mpt nam. Dk dang nhan thay su khdc biet ve kha nang hap thu ion CI- cua ba loai be tong la tuong doi thap. Cu the, clorua hdp thu bdi be tong SRPC la nho nhat trong ba loai be tong va be tong CEM I + FA -h SF CO kha nang hap thu ion CI- cao nhdt. Di^u do co the duoc giai thich bdng luong C-S- H cua ba loai be tong giam ddn theo thu tu CEM I -t- FA -I- SF> CEM I> SRPC. Tran va nnk [2] cho thay clorua hap thu tren be mat C-S-H cao hon so vdi clorua lien ket do su hinh thanh cua muoi Kuzel. Do do, khd nang hdp thu ion CI- cua ba loai be tong tdng theo thii tu SRPC <CEM I <CEM I + FA + SF phii hpp vdi ket qua thi nghiem ciia B. Henrik va nnk, 2013 NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 -THANG 12/2019 61
[17!. B. Johannesson. 2000 il>| linh todn va md hinh hda Glass va Buenfcld [191 cho ihay rang kha nang hip thy ion CI- ting dan d^n gidm su thani nhdp cue clorua lu do. \'iet- gidm lupng clonia tu do xdm nhdp vdo b^ tdng lam gidm nguy ccr an mdn ctia b^Idngc6ith^p|20].[2Ii.
' r c \ N 93-16 122) y^u cau >u dung SRPC vd cac phv gia CO tinh chdt xi mdng df bd sung nhu tro bay (FA), mupi silic (SF) thay vi su dung be tdng thdng thinmg CI;M I cho bd tdng vd k^t cau be tdng cdt thep licp xiic vcn dung djch clorua. Do dd, nii ro an mdn ctia be tdng cdt thep tang theo thu tv SRPC
• CI:M I <-CE.M 1 + FA + SF dudng nhu Id nghich Iy.
Tuy nhidn, can luu y ring ket qua thi nghiem ciia B.
Johannesson, 2000 [18] cho thay hd sd khuech tdn clorua hidu qua gidm theo thu tu CEM I> SRPC>
CI;M 1 + FA + SF. Ddi vai yeu cau ve kha nang chdng an m6n, dnh hudng ciia hd sd an mon hidu qua den su xam nhdp clorua trong bd tdng h^ so khuech tan clorua phdi ldn hon hon kha nang hdp thu ion C1-. Do do lu'u chudn hodn todn phii hpp khi khuyen cao su dyng bd tdng b^n sunphat SRPC va sir dung them phy gia tro bay va mupi sibc cho kdt cau be tong cdt du-]) su dyng ngodi bien dao.
Hinh 3. Khd ndng hdp thy chlorua aia bd tdng CEM- I, SRPC vd CEM I + FA + SF trong mdi trudng dung
djch clorua 5 g.^^ sau mOt ndm
" 0.1 11.: i"i.' o,-i 0,5 0.6 Noii^doiondoniatirdoOiioil)
Hinh 4. Kha ndng hdp thu chlorua cua h& tdng CEM- I, SRPC vd CEM I + FA + SF trong mdi tnrdng dung
dich clorua 20 g.l' sau mOt ndm 4. KET LUAN
Md h i n h dia h d a rat hiiu ich d e s o s d n h k h a n a n g h a p thu ion CI- c u a b a loai c h a t k ^ t d i n h xi m a n g : C E M I, C E M I -H FA + S F . SRPC. S u k h d c bidt ciia k h a n a n g h a p thu ion CI- giija b a loai xi m a n g la rdt nhd. Kha n d n g h a p t h u ion CI- g i a m d a n t h e o thii t u C E M I + FA + SF> C E M I> S R P C . T r a n g thai 6n dinh c u a q u a trinh h a p thu ion CI- dat d u p e sau vai ngdy va dieu nay k h d n g p h u t h u d c vdo loai c h a t k^t dinh. H e sd k h u d c h tan clorua h i e u q u a c h i e m uu th^
hon k h a n a n g lien k e t c l o r u a ddi vdi s u a n h h u d n g den qua trinh t h a m n h a p c l o r u a t r o n g b e t o n g . Gidm h e so k h u e c h tan Id giai p h d p tdt d e g i a m n i i ro an mon cua b e l o n g cdt t h e p . S u d u n g xi m a n g Portiand voi iron phu gia tro bay va m u d i silic Id lua chpn diich ho]) d e giam chi phi xay d u n g t h a y vi s u d u n g
UN CAM ON
Nghien cdu nay duoc tai Pa bdi Quy phat tiidn kho, n,cva cdng nghd Qudc gia (NAFOSTED) trong de tai ma so 107.99-2018.337.
TAI UEU THAM KHAO 1. Van Quan Tran (2016) toward understandinj; „ | depassivalion of steel in CUKTC-I water: theory and thermot^hemu Ccntrale de Nantes, I-ran.:< 2(. • ^
'It contribution -nanisms of exposed to sea modeling. Ecole
NONG NGHIEP VA PHAT TRIEN NONG THON KY 1
KHOA HOC COHG NGHE
2. V. Q. Tran, A. Sowe. S. Bonnet, and A.
Khelidj (2018). A numerical model including thermodynamic equilibrium, kinetic control and surface complexadon in order to explain cation type effect on chloride binding capabihty of concrete.
Constr. Build. Mater., vol. 191, no. 3, pp. 608-618, Sep. 2018.
3. A. Soive, V. Q. Tran, and M. Gasc-Barbier (2018). The advantages of using a geochemical transport model including thermodynamic equilibrium, kinetic control and surface complexatton to simulate the durability of concretes exposed to chlorides and sulphates. Eur. J. Environ.
Civ. Eng., vol. 8189, pp, 1-12, 2018.
4. V. Baroghel-Bouny, M. Thiery. and X. Wang (2011). Modelling of isothermal coupled moisture- ion transport in cementitious materials. Cem. Concr.
Res., vol. 41, no. 8, pp. 828-841, 2011.
5. V. Tran and A. Soive (2017). The advantages of using a geochemical transport model to simulate the durability of concretes exposed to seawater and sulphates. In Multi-physics and Multiscale Coupling in Geo-Environmental Mechanics, 2017, pp. 57-59.
6. T. Xu, N. Spycher, and E. Sonnenthal (2012).
TOUGHREACT User's Guide: A Simulation Program for Non-isothermal Multiphase Reactive Transport in Variably Saturated Geologic Media, version 2.0.
Lawrence Berkeley ..., no. October, 2012.
7. D. L. Parkhurst and C. A. J. Appelo (2013).
Description of input and examples for PHREEQC Version 3 — A computer program for speciation, batch-reaction, one-dimensional transport, and inverse geochemical calculations. U.S. Geol. Surv.
Tech. Methods, B. 6, chapter A43, 2013.
8. A. C. Lasaga, J. M. Soler, J. Ganor, T. E.
Burch, and K L. Nagy 1994). Chemical weathering rate laws and global geochemical cycles. Geochim.
Cosmochim. Acta, vol. 58, no. 10, pp. 2361-2386, 1994.
9. I, Baur, P. Keller, D. Mavrocordatos, B.
Wehrli, and C. A. Johnson (2004). Dissolution- precipitation behaviour of ettringite, monosulfate, and calcium silicate hydrate. Cem. Concr. Res., vol 34, no. 2, pp. 341-348,2004.
10. K. De Weerdt, D. Orsakova, A C. A. MuUer, C. K. Larsen, B. Pedersen, and M. R. Geiker (2016).
Towards the understanding of chloride profiles in marine exposed concrete, impact of leachmg and moisture contenC Constr. Build. Mater., vol. 120, pp.
418-431,2016.
11. D. A. Kulik et al., (2013). GEM-Selektor geochemical modeling package: revised algorithm and GEMS3K numerical kernel for coupled simulation codes. CompuL Geosci., vol. 17, no. 1, pp, 1-24,2013.
12. V. Q. Tran, A. Soive, and V. Baroghel-Bouny (2018). New model for chloride reactive transport in concrete including thermodynamic equilibrium, kinetic control and surface complexadon. Cem.
Concr. Res., vol. 110, no. April, pp. 70-85,2018.
13. A. Soive and V. Q. Tran (2017). External sulfate attack of cementiUous materials: New insights gained through numencal modeling including dissolution/precipitation kinetics and surface complexation. Cem. Concr. Compos., vol. 83, no.
July, pp. 263-272,2017.
14. A Soive, V. Q. Tran, and V. Baroghel-Bouny (2018). Requirements and possible simplifications for mulu-ionic transport models - Case of concrete subjected to wetting-drying cycles in marine environment Constr. Build. Mater., vol. 164, no.
January, pp. 799-808,2018.
15. S. Gali, C. Ayora, P. Alfonso, E. Tauler, and M. Labrador (2001). Kinetics of dolomite-portlandite reaction: Application to portland cement concrete.
Cem. Concr. Res., vol. 31, no. 6, pp. 933-939,2001.
16. T. S. Nguyen, S. Lorente, and M. Carcasses (2009). Effect of the environment temperature on the chloride diffusion through CEM-I and CEM-V mortars: An experimental study. Constr. Build.
Mater., vol. 23, no. 2, pp. 795-803, 2009.
17. B. Henrik and E. Serensen (2015). New model for chloride penetration into concreted?
Investigation of marine bridges in 2012, 2015.
18. B. Johannesson (2000). The Effect of Different Cements and Pozzolans on Chioride Ingress into Concrete Division of Building Materials Tlie Effect of Different Cements and Pozzolans on Chioride Ingress into Concrete Bjdm Johannesson.
2000.
19. G. K. Glass and N. R. Buenfeld (2000). The influence of chloride binding on the chloride induced
NONG NGHIEP VA PHAT TRIEN NONG THON - KY 1 - THANG 12/2019 63
corrosion n^k in reinforced concrete.
I.UIIU3IUU I i-.ri UI KTUUUIUCU t u i M C i f . v^'Nui.-i 3C1., l l , V l \ y . 3 ^ D \.~,UX } . tpTtiOn
vol. 42. no. 2. pp. 329-344.2000. concrete structures - Requirementd of proie*.
o« II V D c^ ^ v T ,.,,1 n from corrosion in manne environment. 2012.
20. U. .\ngsi, B. Elsener. C. h. Larsen. and O IJ^HIA 1- Vcnnesland (2009). Cnlical chloride conteni ui 23. NF i:.N 197-1 (2012). Ciment - ' ™ ', reinforced concrete- A xv^^^v^^ Cem. Concr Res., vol composition, specifications et criteres de conlormire 39, no. 12. pp. 1122-1138.2009. des ciments courants. 2012.
21. K. Y. Ann and H.-W. Song (2007). Chlonde threshold level for corrosion of steel m concrete.
Corros. Sci.. vol. f;i. no. 11. pp. 4113-4133.2007.
USING NUMERICAL MODEL FOR PREDICTION OF CHLORIDE BINDING CAPACnY OF CEMENTmOUS EXPOSURE TO CHLORIDE SOLUTION
Tran Van Quan Summaiy
Steel corrosion is one of major problems that affect the durability of reinforced concrete structures.
Chloride binding is the key parameter for the steel corrosion risk of reinforced concrete exposed to chloride soluUon. The durability of reinforced concrete can be assessed by the prediction of chloride binding capacity of reinforced concrete. To assess correctly the chloride binding capacity of concrete, iiunitTtius numerical models have been developed however these numencal models are the empirical model which depend strongly on the experimental results. The geochemical model can predict the chloride binding capacity of different concrete without performing expenmental test. The geochemical model is bni'Sly described in the modelling approach. The chlonde binding capacity of CEM I (Portland cement), Cl-.M I + Fly Ash (FA) + Silica Fume (SF) and Sulfate Resistance Portland Cement (SRPC) exposure to chloride solution 5 g.l' and 20 g.l' will be predicted by geochemical model. The kinetic of bound chloride is also discussed.
Keywords: Concrete, chloride binding capacity, geochemical model, Portiand cement. Sulfate Resistance Portland Cement
Ngudi phan bi^: PGS.TS. NguySn Quang Phii Ngiy nh$n Wu: 21/10/2019
Ngfiy thOng qua phin bi§n: 22/11/2019 Ngiy duyet dang: 29/11/2019
NONG NGHIEP VA PHAT TRIEN N O N G THON - KY 1 - THAN©
