I KHOA HOC mMnjuMjm
M 6 PHONG Q l A TRiNH IHIJ^ HOA XI M.\NG C6 SC D i TRO BAI1. MUQI SILIC BANCi CONG C l S 6 VCCTi
Tran Vin Quan Truang Dgi hpc Cdng nghf Giao thdng W" ""
NguvonHiSTiNSm Vien Thuy difn vd \wK ^ufmgldi lao Tdm tit: Cdng cu si Virtual Cement and Concrete Testing Laboratory viet Idt la (I C CIL) la phdn mem dtrgc phdl trien bai Vifn lieu chudn vd cdng nghf Hoa Ky vdo ndm 201)1. nien nay cdng cy ndy vdn dur?c liep ttfc hodn thifn bdi Vifn lieu chudn cdng nghf Hoa Ki'. he thong cac Irudng dgi hpc vd cdc cdng ly sdn .mat xi mdng. Afyc lieu cua viec phdl trien cdng cti so VCCIL la dif dodn cdc linh chdi cua be tdng tuoi cUng nhu be long ddng kit dif a vdo cdc dieu kien trpn be ldng, dieu kifn bdo duang mdu. VCCTL giup xdc dinh Ihiet ke toi uu cda hon hap be tdng, gidm sd Itrpmg mdu khdng hieu qud cdn lien hdnh Irong phdng Ihi nghiem, tir dd liet kifm dugc thdi gian vd chi phi cho xdy dung cdng trinh. Thdng qua vifc md phdng qud trinh thOy hda cua ba logi cdp phdi hd xi mdng: 100% xi mdng, 20% tro bay + 80% xi mdng vd 20% mupi silic + SOVo xi mdng, bdi bdo se gidi thifu ve cdng cu sd VCCTL ciing nhu cdc thdng sd ddu vdo cdn thiet de cd the md phdng qud Irinh Ihuy hda cua be tdng xi mdng de tir dd cd the dif dodn mpt so linh chdt ca hpc cda be tdng.
Tir khda: Cong cy so. VCCTL, be long, tro bay, mupi silic, thuy hda, xi mdng
Summary: The Virtual Cement and Concrete Testing Laboratory (VCCTL) is a numerical tool developed by Ihe National Institute of Standards and Technology (NIST) in 2001. Currently, the tool is slill being improved by NIST, a system of universities and cement companies. The objeclive ofthe development ofthe VCCTL numerical tool is lo predict the properties of fresh as well as hardened concrete based on concrete mixing conditions and sample curing conditions.
VCCTL helps determine the optimal design of concrete mixes, reducing the number of inefficient samples that need 10 be carried out in the laboratory, thereby saving time and cost for construction By simulating Ihe hydration process of three types of cement slurry mix- 100%
cement. 20% fly ash + 80% cement and 20% silica ,fume + 80% cement, the article will introduce about VCCTL as well as Ihe necessary input parameters to simulate the hydration process of cement so that some mechanical properties of paste can be predicted
Keywords: Numerical tools. I CCTL. concrete, fly ash, silica fi^me, hydration, cement
\. DijiTVANDfe trong cie tieu chuan nhu ASTM Cino rn Ngiy nay thiit ki hon hpp bd tdng cimg vdi ASTM C2I5 [2]. Cac phuong phan th' b - dinb gii cic tinh chit cua bd tdng Oroi va be 6-ong phong thi nghidm thong thu' ' j ''™
tdng sau khi ddng kit dupc thyc hidn chd yiu kdm vi mit tiidi gian, ddi hdi nhi™^ " ' tdn dya vio cic phuong trinh thyc nghidm cd sin lupng ldn nguyen vjit lidu cimo . • "8 ^°
thuat vidn tay nghd cao di 'c6 thi ti^^'J^ ^^
Ngiynhanbii: 1^3/2020 ^ S r i E ^ ' i f l ' l f i ™ «."*> J I * ' Ngaynnanooi. lorjiiuiu - "Bnidm trnno Ngiy thdng qua phan bi?n: 15/4^020 phdng, cic thi nghipm doi khi phii chd d Ngiy duydt ding: 17 4 2020 liu di cd kcl qua. Cdng cy so Virtual r *
"-anient
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and Concrete Testing Laboratory viet tdt la (VCCTL) la phdn m^m dupc phat trien bdi Vi?n tieu chudn va cdng nghe, Vien nghien cuu xdy dung va ehay Hoa Ky vdo nam 2001.
Cdng cy ndy dupc phat trien vdi muc dich
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giam chi phi thi nghiem va riit ngan thdi gian thiet ke cap phdi be tdng. Bang I tdm tdt so sdnh giiia viec thiet ke cap phdi truyen thdng trong phdng thi nghiem \ a sir dung cdng cu sd VCCTL
Bang 1: So sdnh cdc phuomg phdp thtr nghiem hien tai va thir nghiem so hda | 3 | Phuomg phdp thiiru nghidm hien tai
Dua tren cac thtr nghiem vat ly - Ky thuat vien tay nghe cao
Can nhieu vat lieu
- Thdi gian cd ket qua : tuan/thang - Chi phi cao
Phu-ffng phdp thu nghiem s6 hoa - Dua tren su tinh toan ciia may tinh - Tinh toan chuyen sau
- Nhu cau \ c \at lieu nhd - Thdi gian cd ket qua : Gid/ngay - Chl phi thap
Cac dau vao can thiet cho cdng cu sd VCCTL va cac tinh chat cua be tdng ma edng eu cd the du doan dupe tdng hpp trong hinh I.
Xi man a Thanh phan hda
hoc
Dieu kien bao dudng Doan nhiet, dang nhiet. mdi trudng kin. bao hda, bao hda/
tde dp bay hoi khdng ddi Cdt lieu
Phan loai: khdi lupng rieng. dp bao
hda. hinh dang.
VIRTUAL C E M E N T AND C O N C R E T E T E S T I N G
LABORATORY (VCCTL) Vat lieu phu gia xi
mang Kich thudc hat, hdn hpp: mudc silic, tro hnv vi I n , - a n trnnlin
Cap phdl thiet ke Ty le N/X. % spi; %phu gia hda hoc. ham lupng khdng khi
Tinh chat dudoan Mire do thiiy h d a ^ \ Dp eo ngdt Su tham thau qua Id rdng - — . Nhiet nang sinh ra
Dp khuech tan eiia be tdng - - Kha nang lam viec Md dun dan hdi Phat trien cudng dp
Hinh I; Dir lieu ddu vdo cdn thiei cho viec du dodn cdc tinh chdt b&i phuang phdp thu nghiem sd [4]
Ngoai ra. hien nay viec su dung cac thanh phan phy gia nhu tro bay, xi Id cao hay mudi silic ngay cang phd bien vdi ham lupng thay the \i mang ngay cang cao. Tuy nhien hien na> tai Viet Nam. viec thiet ke cap phdi be tdng cd su dung cae phu gia van dupe thuc hien bang cac thi nghiem trong phdng thi nghiem vdi sd lupng mau ldn ddn ddn chi phi
thi^t ke cap phdi bi tang cao, ddng thai can thdi gian dai de tim ra cap phdi dan den cham tidn dp thi edng. Do dd viec irng dung cdng nghe sd VCCTL se la mot phuang phap thi nghiem sd giiip riit ngan thdi gian thi nghiem cdp phdi be tdng trong qua trinh thi cdng. Cac tinh chat co hpc ciia be tdng phu thudc rat Idn vao cae dieu kien thiiy hoa cung nhu thanh
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phin chii kit dinh. E>o dd trong bii bao, VCCTL dupc dng dyng md phdng qua trinh thuy hda cic loai bd tdng cd su dyng cac chit kit dinh khic nhau: (I) khdng su dyng DD bay.
xi Id cao, (2) cd su dyng 20% no bay (3) cd sii dyng 20% mupi silic. Kit qui cho Uiiy khi ning ip dyng ciia cdng cy si VCCTL vao duel ki tilinh phin cip phdi bd tdng xi ming ngoai thyc ti tai Vidt Nam
2. CAC T H 6 N G S 6 D A U VAO CAN
THifeT CHO C 6 N G CV VCCTL
Hinh I: Thanh phdn chdt kit dinh:
xi mdng vdphtt gia
COng tucmg ty nhu vide Uiiit ki cip phdi tix>ng phdng thi nghidm, vide md phdng bing cdng
cy \ t CTL eiing cin cic Uidng sd sau • ( ^ thinh phin chit kit dtoh (Uiinh phin clinK ^ him lupng Uiach cao tiong xi ming; P^V ^^
hoa bao gdm tto bay, xi Id cao. mupi silic, c , di vdi, vdi bpt) (Hinh I). Thcifi titutog cac Ihinh phan nay di cd tiong co sd <"* I''" ^ S cdng cy VCCTL, tit)ng tiudng hpp i^Jttei ngudi dimg cd tiii ty djnh nghia thanh phan xi ming hoSc cic phy gia khic cho phii hpp dung vdi diiu kidn thyc td (Hinh 3).
MIxA
Wster Water/Binder raUo O Add Coarse Aogresate u Add Curse Aggreffate 2 u Add Fine Aggregate iJ Add Fine Aggregate 2
MaM fraction 0 5697 03103 04B J
lOO 00 [00
;oo 1 Volume fraction 04081 J
•0 5B1B 1 ,00 i 00 n 0 0 1 IO.D 1
Hinh 2: Thdnh phdn cap phdl:
ty le nuac/xi mdng
(2) Thinh phin cip phdi ciia bd tong bao gdm:
ty Id nude/chat kdt dinh (xi ming va phy gia hda), ham lupng chit kdt dinh, cit lidu bao gim cit lidu to (da, sdi) va cdt lieu min.
Cling tuong ty nhu xi ming va phy gia hda, thinh phan hat ciia cot lidu thudng da tlch hpp trong CO sd diJ lidu cda cdng cy, tuy nhidn niu cin tiiiit khi s i dyng eic loai o6t lidu mdi cd thi hipu chinh eho phi hop (Hmh 4)
(a) (b)
TAP o d KHOA Hpc VA CONG NGHE THUY Ld S6 59 - 2020
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(d)
(c)
Hinh 3: Hieu chinh thdnh phdn (a) xi mdng ; (b) xi Id cao; (c) tro bay; (d) cdi
^
Hinh 4: Hieu chinh thdnh phdn (a) cot lieu thd tie luyen thep; (b) cot lieu min Trong bai bao, nham gidi thieu kha nang md
phdng ciia qua trinh thiiy hda xi manng, bai bao se lua chpn md phdng qua trinh thuy hda cua hd xi mang khdng cd sir dung cdt lieu. Xi mdng Portland thdng thudng dupe chpn ky hicu Id cementMO, tro bay ki hieu flyashOl.fly va mupi silic SF. Ty le cap phdi vdi ty le nude/chat ket dinh 0.45, vdi cap phdi sir dung tro bay, ham lupng tro bay dupc xac dinh theo IN le tro bay/xi mang Id 0.10 va 0.20. Lupng xi mdng sir dyng la 300 kg cho 1 m"* be tdng.
Ngoai ra dieu kien thiiy hda cung dupc md phdng trong cdng cu VCCTL. Tiiy chinh dilu kien thuy hda cua hdn hpp: nang lupng tao ra
bdi phan img thiiy hda ciia xi mang, phan img puzzolanic. xi Id cao phan irng (neu sir dung), nhiet dp dudng ban dau: dang nhiet hay doan nhiet hoac ket hop ca hai, dieu kien mau bao hda hoac khdng bao hda. Thdi gian gia thict thiiy hda ciing vdi dp thiiy hda dupe djnh nghTa trong khoang (0-1) (Hinh 5). Trong bai bao nay, gid thiet trong ca ba cap phdi: (1) 100% Xi mang; (2) tro bay thay the 20% khdi lupng xi mang va (3) mudi silic thay the 20%
khdi lupng xi mang, cac dicu kicn thiiy hda la nhu nhau ; dang nhiet T=^25°C ; sau 28 ngay he sd thiiy hda 0.95; trang thai bao hda trong qua trinh bao dudng.
TAP CHf KHOA HOC VA C O N G NGHE THUY LOI S 6 59 • 2020
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Hinh '• li kit qui oia dd duly hda cua ba IMU cip phdl hot \i ming. tto bay vi mudi silic. Kdt qua niy cho thiy ho xi ming ed su dyng 20% mup' silic cd tic dp diuy hda nhanh hon so vdi su dyng 100% xi ming vi 80«'<, xi mang+20% tto bay Diiu niy dan tdi pH cda hdn hw bfi "' ndng mudi silic cd pH cao tai didi didm sdm hon so vdi sii dyng 20% tto bay (Hinh 7)
Hinh 5: Diiu U^ My hda ctia be ldng, vOa, ho xi mdng 3. P H A N T I C H KtT QUA
Hinh 7: pH da hd xi mdng trong 2 trudng hop stf dvng Iro bay vd sir dtfng mupi silic Hinh 8 cho Uiiy dd iSng ciia cic phip phdi diu giim khi dd thiiy hda ting Iheo thdi gian. Sii dyng 100% xi ming, dp ling giim nhanh chdng sau 12h vi dat gii tti nhd nhit, tuy nhidn vdi cap phii sii dyng tro bay vi mudi sihc dd ring vin tiip tyc giim sau 28 ngiy. Cd thi thiy ring tio bay vi mudi silic thay dii tic dd thiiy hda vi Dp thdy hda Iheo thai giat trong 28 ngdy tinh chit cua hin hpp hi xi ming Hinh 6:
(a) (b) Win* 8: Dp ring da hi xi mdng iheo thai gian (a) sau 28 ngiy (b) sau 25 gid
20 TAPCHlKHOAHQCVACdNGNGHCTHUVlC)IS6S9-2020
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Bing 2: Cic tfnh chit cor ly ciia b i xi ndng, tro bay v i mufi silic sau 28 ngiy Cic tfnh chit Cff 1^
Md dun ching cit (GPa) Md dun Young Hd si Poisson DpiSng
d p phii 100% zi ndng
7.66 19.55 0.275 0.23
20% tro bay 7.5 18.65 0.269 0.275
20% mu$i silic 6.37 16.23 0.274 0.30 Cd th€ nh$n thdy rdng gid trj mo dim Young
E (hay cdn gpi md dim ddn hoi), h$ sd Poisson V ciia ho xi mdng rdt sdt vdi gid trj thvc nghidm E=16 Mpa, v=0.26 trong nghidn c(tu ciia Becker vd nnk [5]; hay v=
[0.20^.32] trong th\rc nghipm ciia Tang [6].
Sir dyng 100% xi mdng cho cdc tinh chat co ly tot nh4t trong 3 dp ph6i vdfi md dun ch6ng cdt, modun ddn hoi ldn vd dp rong thdp. Ket qud so sdnh giQa cap phdi 100% xl mdng vd 80% xi mdng+20% tro bay d bdng 2 phii hpp vdi nghiSn cihi thuc nghidm v^ anh hudng ciia tro bay den cudng dp cua be tdng, dupc cdng bd trong Tdi li$u t^p huan td chirc thi cdng be tdng khdi Idn vd b6 tdng cd sii dvng tro bay trong xdy d\mg cdng trinh thuy Ipi phdt hdnh 2019 bdi Cvc qudn 1;^ xdy dung cdng trinh, Bp Ndng nghi?p vd Phdt trien Ndng thdn [7].
4. ld:T LUv^JV
Hi^n nay ung dung cd nghe sd hda dupc dp dyng trong mpi Imh vvc ddi song xa hpi, phii hpp vdi vi?c phdt trien cdng ngh? 4.0. Khdng ndm ngodi xu the dd, ITnh vvc xdy dung t^
Vipt Nam cung dd dua vdo nhihig cdng ngh^
unag dvng cdc cong ngh^ sd ndy. Do v$y bdi bdo da gidi thi^u mpt cdng cv sd trong thilt ke thanh phdn c4p phdi bd tdng xi mdng cd siJr dvng cdc phv gia hda khdc. Cdng cv so VCCTL dd thdnh cdng trong vi?c md phdng qud trinh thuy hda ciia hd xi mdng vd hb xi mdng cd sii dvng tro bay vd mudi silic. Ket qua dupc so sdnh vdi cdc kit qud thi nghidm trong thvc t§, cdc kdt qud s6 phii hpp vdi kit qud thi nghidm vd cdc kSt l u ^ cua cdc nghien cuu dd dupc cdng bd trudc dd. Cdc kit qud cdng cv sd VCCTL da du dodn dupc trong nghien ciiu ndy Id : Md dun chdng cdt, Md dun Young (Md dun dan hdi), h? sd Poisson vd d§
rong ciia c ^ phdi hd xi mang, tro bay vd mupi silic. Cd thl thiy rdng cdng cy sd VCCTL Id khd thi dd dp dung vao thiet ke cap phdi b6 tdng tai Viet Nam, ddc bi?t cho cac cdng trinh sii dung be tdng khdi ldn nhu dip thiiy d i ^ , hd chiia. Bk cd thl dp dvng r^ng rdi cdng cv sd VCCTL vdo thvc tl, cdn so sdnh nhieu kit qud thi nghiem dd dupc thuc hi^n vdi kit qud ciia cdng cv so.
TAI Lifu THAM KHAO
[1] COI Committee, "Test Method for Compressive Strength of Hydraulic Cement Mortars (Usmg 2-in. or [50-mm] Cube Specimens)," ASTM hitemational.
[2] C09 Conunittee, "Test Method for Fundamental Transverse, Longitudinal, and Torsional Resonant Frequencies of Concrete Specimens," ASTM hitemational.
TAP C H l KHOA HOC VA C O N G N G H E T H O Y LOI S 6 59 - 2 0 2 0 21
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[3] S. Erdogan. E. J. Gaiboczi, and J. W. BuUaid, "Pnxliciion ol Elastic Properties of Concrete Using Uie Vutual Cement and Concrete Testing Uboratory," Nov. 2007.
[4] -Bullaid, J.W., Ferraris, C.F., Gatboczi, E.. Martys, N. & Smizman, P. 2004, Virtual Cement- Reprinted from huiovations in Portland Cement Manufacmnng, Chapter lO-^;^'^
J.l. Bhatty, F.M. Miller & S.H. Kosmalka, Poitiand Cement Association, 5420 Old Or.
[5] Becker Jens, Jacobs Uurence J., and Qu Jianmin, "Characterization of Cement-Bas«l Materials Using Diffiise Ultiasound," Joi<nio/o/£Hgi/«wi»lg WecAaracs, vol. 129, no. 12, pp. 1478-1484, Dec. 2003, doi: I0.106I/(ASCE)0733-9399(2003)129:I2(1478).
[6] C.-W. Tang, "Effect of prcsoakmg degree of lightweight aggregate on the properties of lightwreight aggregate concrete," Conpulen and Concrete, vol. 19, no. 1, pp. 6 ^ 7 8 , Jan.
2017, doi: I0.12989/CAC.2017.19.I.069.
(7] "Tii lidu t$p huin td chiic till cdng bd tdng khii ldn v i bd tdng cd sii dyng tto bay tiong xiy dyng cdng ttinh tiiiiy Ipi," Cyc quin ly x i y dyng cdng ttinh, B i Ndng nghipp v i Phat ttiin Ndng thdn, Nghd An, 2019.
21 TAP CHl KHOA HOC VA CONG NGH( THUY ten 5 4 5 9 - 2 0 2 0
