KHONG CHE CHAT L J O N G THI CONG BETONG MYTHUAT Fu Li Rong ABSTRACT The article herein is a summary of obtained experiences related to Vietnam Hai PhongThermal Power Plant jetty project fair face con[.]
KHONG CHE CHAT L J O N G THI CONG BETONG M Y T H U A T Fu Li Rong ABSTRACT The article herein is a summary of obtained experiences related to Vietnam Hai PhongThermal Power Plant jetty project fair-face concrete construction quality control during concrete preparing, formwork fabrication, concrete casting and curing Fair -face concrete quality standard and quality defects usually appear during construction are presented And feasible pre control measures had been proposed in respect of w/ork technique, defect repair and final product protection Fu Li Rong Cong ty tap doan cong trinh giao thong tinh Giang To Trung Quoc chi nhanh To Chau 66^UnT1ff7 6.2009 Tieu chuan chat lUtfng e tdng my thuat la loai mdt 1.1 Can cd theo yeu cdu ITB, lan dung mau, khdng lam bat tieu chuan chat lUcfng cua be tong ed trang tri gi ben ngoai, true tiep dung hieu qua be mat tU nhien my thugt nhUsau: cua be tdng lam mat trang tri, be Be ngoai be tdng bang phang, mat bang phang, nhin bdng, mau nhan nhui, mau sac deu, dp sang sac deu, gdc canh rd rang, khdng bdng dat den F2(±2) bj xude hoac nhiem ban Be tdng Be mat be tdng khdng bpt khi, my thuat vdi dac diem vda nang khdng rd, khdng van, be mat khdng vda day, nha, be ngoai bdng xuat hien hien tUpng td ong, san sui, nhan, dep de, tdng gia thi khdng cd vet ndt va khdng Id thep cdng thap, tien dp thi cdng nhanh Oudng true cau kien thang, kich nen cang duqc sd dung thudc chinh xae, gdc canh vudng bien d va ngoai nude van, dudng net thang Ket cau phan tren cua edng Oudng ndi cdp pha kin, khdng trinh cau cang Nha may Nhiet dien Ipt anh sang, khdng cong venh, bu Hai Phdng sd dung he thdng tam Idng keo lap dat ngan, dam ngang dpc va ban mat cau, xung quanh Id bu Idng bang phang, tdng edng khoang 30000m^ be kin, dudng ndi cdp pha va dUdng ndi tdng He thdng dam ngang dpc la thi edng ngoai khdng cong venh, hinh ta tay gdc, dp cao day cua dudng ndi thang he dam ngang dpc hoan toan ko Vi tri cau kien can ehdn chinh xae, gidng nhau, lam cdp pha rat khd dudng ndi vdi be tdng bang phang khan, dp khd thi edng cung rat va nhan bdng Idn can ed theo yeu cau van 1.2 Thong qua viec thi cong kien mdi thau (ITB) cua chu dau t u be tong my thuat tai cong trinh (Cdng ty ed phan nhiet dien Hai cau cang Nha may Nhiet dien Hai Phdng), toan bd be tdng cua ket Phong, cho thay mot so van de cau phan tren deu yeu cau dat den ve chat lugng nhu sau: tieu chuan cua be tdng my thuat Can edtheo yeu cau cua ITB, qua Do vay kien triJc sU cua ESBI (Cdng thi cdng be tdng my thuat phan tren ty t u van edng trinh qude te Alien) khu vUe cau cang, tren co sd phan (dudi day gpi la IE) cd yeu cau rat tich be tdng mau, ket hpp vdi kinh cao ddi vdi chat lupng thi edng be nghiem thi edng nhieu nam, tham tdng my thuat, hoan toan thi edng khao ve chat lUpng thi edng be tdng theo yeu cau cua ITB, qua va ngoai nudc chung tdi da trinh thi edng ddi vdi be tdng my thay rang qua trinh thi edng be thuat toan bd qua trinh t d mua tdng my thuat cd the gap phai mdt nguyen vat lieu den be tdng deu sd van de ve chat lupng nhu sau: khdng che mdt each nghiem ngat Cdp pha bj lech, bj phdng dan Yeu cau sau dd be tdng xong den cau kien bj bien dang: chu yeu mdt lan dung mau, co ban dat den ban day bj sut dan den cdp pha yeu cau be tdng my thuat cua ITB mat ben va cdp pha day bj tach rdi B Phan day bj chay vda nen ed hien tupng thieu gdc, gdc xien bien dang Cdp pha mat ben bj lech, bj phdng dan den bien dang lam cho dp bang phang cua be mat vupt qua yeu cau Vj tri thep cua he thdng dam ngang, dpc khdng chinh xae, dan den true cua cau kien khdng thang, kich thude tiet dien khdng phu hpp vdi yeu cau Vj tri lap dat cua gdc xien khdng chinh xae va xd ly dudng ndi chd gdc xien khdng tdt, dan den be mat gdc va canh khac nhau, dudng net khdng thang Phan map md tai gdc am dUOng va phan map md d mep ndi cdp pha Idn se gay hien tupng Idi cue tren be mat be tdng Mep ndi cdp pha khdng kbit se dan den hien tupng dd vda Lap dat buIdng keo khdng ed quy tac Id buldng khdng lap kin, khdng bang phang, lam cho be mat be tdng bdn xung quanh buldng bj chay vda, bj 16 chd Be mat be tdng xuat hien sU khac biet ve mau sac, ed hien tUpng bpt khi, vet nude, bi rd, td ong tang sudt nguyen lieu Idi thd), san sui, be mat ed vet nut 2.Can CUT theo yeu cau chat lUoTng cua ITB thi cong can chu y nhuTng diem sau: 2.1 Chgn loai cop pha va gia cong ldp ddt: - Do can dat den tieu chuan cua be tdng my thuat nen thi edng thUe te phai chu y den chat lupng cdp pha Chung tdi sd dung cdp pha tre ep mat tao dp bdng day 1,8cm (khdng dung loai cdp pha thep truyen thdng) Cdp pha tre ep yeu cau dat den eae tieu chuan ky thuat sau:Cudng dd ehdng cong venh dat den 74Mpa, tinh dan hdi iai.ri04Mpa.Cdp pha tre ep yeu cau phai ed tinh chju nude tdt, khdng de bj phdng hoac eo, be mat chju ma sat va ed tac dung ehdng ndt, khdng phan tang Cdp pha day tren gian giao chd A lap dat nhdng go vudng theo hudng dpc (sd dung go bach ed sin tai Viet Nam) lam he thdng ehdng dd, sau dd tren go vudng lap dung cdp pha tre ep Cdp pha mat ben diing cdp pha tre ep, go vudng lam ehdng ddng, dng thep ngang lam chan, ben ngoai chan dung buldng keo ed djnh cdp pha - Toan bp yeu cau vdi cdp pha nhu sau: be mat phai saeh se, khdng cd vet, khdng cd 16 thung Neu xuat hien cae hien tUpng tren, phai lam phang be mat cdp pha, sau dung keo sudt dan Toan bdedp pha deu dung dung dich thao cop pha Rhaofinish 202-Release agent by BASF, de sau be tdng be mat be tdng se tron bdng, de be tdng va cdp pha tach rdi dupc de dang.Trong dung djeh thao cdp pha pha them 1% dung djeh tieu bpt khi, mdt lupng dung djeh tieu bpt nhat djnh se khdng chi lam cho bpt nhanh chong bi tieu diet ma mdt thdi gian tuong ddi dai edn ngan chan su hinh cua bpt Dung djeh thao cdp pha yeu cau phai xoa deu, dpi sau dung djeh dn djnh thi ghep cdp pha - TrUde thi edng cop pha day, trai go vudng am ban, diing phuong phap day dai de dat go vudng ngang mat nude, day la dieu kien dau tien de tao dp bang phing cua cdp pha day phu hpp vdi yeu cau Chd ghep cua hai tam cdp pha tre ep va chd ghep vao dau epe nen dan bang keo mat - Sau ghep xong cdp pha day, yeu cau ddng dinh gdc xien 25mm*25mm; tat ca gdc xien; yeu cau quy each hinh dang, dUdng net thing Khoang gida cop pha day, cdp pha canh va gdc xien dung Silieol dan Iai - Gia edng cdp pha canh: Sau hoan edng viec bude thep, trUde ghep cdp pha canh phai tien hanh kiem tra tang bao hd thep; day la mdt dieu kien tat yeu de bao dam khudn hinh cho cdp pha va khdng bj Id thep, dung thude dp bang phing mat nude de tien hanh kiem tra, loai bd nhdng hien tUOng map md - Lip dat buldng keo: sau hoan viec thi edng go vudng theo hudng thing ddng, tien hanh lap dat buldng keo Ld buldng bd tri M*l M quy tie hinh ma tran Dung may due 16 chuyen dung tao 16 to nhd dudng kinh ngoai dng PVC ben ngoai buldng Sau buldng keo da lap kbit diing Silieol lam phing xung quanh 16 bu Idng Tai vj tri ndi tiep d gdc xien gida cdp pha mat ben va cop pha day phai diing keo mat de dan ndi, ddng thdi tai gdc day ben ngoai ciia cop pha canh diing mieng go vudng de chen gdc de phdng be tdng, cdp pha canh va cdp pha day tach - Toan bd cdp pha mat trai hay phai ehi nen diing lan, de bao dam chat lupng be mat ciia be tdng 2.2 Sap ddt va bugc thep Mudn bao dam kich thude ciia cau kien va lip dat cdp pha diing vi tri chinh xae ciia thep, phai lam tdt cac viec sau: - oam bao kich thudc phdi lieu thep: Phai gid cho eae loai thep va thep dai bing phing, ngin, mdc cong chinh xae - Ndi va budc thep: Oe tien cho viec be tdng va tiet kiem thep can tang eUdng thiet bj ndi va han ndi thep, nang cao chat lupng ndi thep va trinh dp ky thuat thi cdng Phan thua ciia day bude thep nen gap vao ben cau kien de tranh 16 ngoai hinh vet ri, anh hudng den chat lupng cam quan ciia be tdng my thuat - Bao dam chinh xae vj tri sinh re cua thep, phai quan djnh vj hinh thang tai vj tri chan thep dam, de ed djnh thep chinh khdng bj chuyen vj, ddng thdi khong che duoc khoang each da sip xep - Ojnh vj chinh xae vj tri bu Idng can ehdn Buldng ehdn sin ciia cdng trinh cau cang ed rat nhieu ehiing loai, vi tri ehdn phdc tap, cd anh hudng rat Idn den cdp pha Do vay su chinh xae ciia vi tri buldng va sU g i n ket hoan hao gida buldng va cdp pha la rat quan ddi vdi chat luong i^VilTISIT 6.2009 67 ben ngoai ciia be tong Sau due Id cop pha tai vj tri buldng, diing keo mat bjt kin xung quanh 16, ddng thdi chu y tinh bang phang ciia phia ben mep ngoai de tranh hien tupng ddng ket ban dau hoac bi mat nUdc Trudc dUa vao cdp pha tai edng trudngmoi mot xe deu phai kiem tra dp sut va thd nhiet dp Phai can ed theo yeu cau xd ly ciia bao cao cac hang muc khdng phii hpp da duqc liet ke, xae djnh ed phuong an sda ehda nhdng phan be tdng ed khuyet tat 2.3 Thiet ke mdc be tong va kiem tra nguyen vat lieu - Mac be tdng va chat lUpng nguyen vat lieu anh hudng true tiep den chat lupng ben va chat lupng ben ngoai ciia be tdng vi vay mac be tdng va dam bao chat lUpng vat lieu la rat quan trpng - Tien hanh thiet ke Uu boa ddi vdi mac be tdng: trUde tien diing ty le ciia phdng thi nghiem tien hanh lam nhdm mac theo yeu cau ciia IE, mdt mat kiem ehdng eUdng dp ciia be tdng ddng thdi tien hanh thd ddi vdi ca nhdm de so sanh Sau dd cdp pha, chpn mac be tdng ed be mat dat tieu chua'n ciia be tdng my thuat 2.4 Do be tong vd cong tac bao dudng: - Khi trdn be tdng diing mac be tdng va nguyen vat lieu phii hpp: Trong qua trinh thi cdng be tdng ndi epe, dam ngang dpc, ban mat cau tai du an cdng trinh cau cang nha may Nhiet dien Hai Phdng ludn diing mac betdngphii hpp va diing loaiximang thdng thudng; diing chat phu gia eiing mdt noi san xuat, cot lieu mjn, thd ciia eiing mdt noi gia edng Oay la tien de de chat lUpng be mat be tdng dupe dam bao -Trong thdi gian be tdng neu gap trdi mUa, nhat thiet phai cd bien phap bao ve can thiet nhU diing tam phim day len phan be tdng da xong - Khi be tdng, diing xe bom chd be tdng den bom vao van khudn, dam bao cao dp rpi nghieng tu CLia be tdng nhd hon 2m, ddi vdi he dam ngang dpc hinh vudng, be tdng diing phuong phap tuan hoan tien hanh lien tue, dp day mdi tang nhd hon 30cm, dp ddc nhd hon 1:3, - Bao dudng pham Khi va sau be tdng, phai diing vai bat che mUa ddi vdi be tdng va phan be mat Id ngoai Be tdng xong, dpi be mat dat den eudng dp nhat djnh, diing vai dja ky thuat phu len va kjp thdi tUdi nude saeh de bao dudng, phai tri lien tue thdi gian bao dudng am Ucrt 14 Oe tranh hien tUpng be mat mat nUde xuat hien vet nut anh hudng den be mat va tinh ben - Nhdng chu y trdn be tdng: Oe bao dam lupng nguyen vat lieu dau vao ciia be tdng chinh xae phai tien hanh lUdng tU ddng ddi vdi nude, ximang, chat phu gia, cat, da dam, trdn manh de bao dam sU deu nhuyen va tinh g i n ket cua be tdng Khi trdn, nhiet dp mdi trudng d Viet Nam tUPng ddi cao, ITB yeu cau nhiet dp be tdng vao khudn khdng vUpt qua 30 dp, vay, tai hien trudng phai ap dung eae bien phap: Diing nude gieng sau tUdi udt eat, da de lam giam nhiet dp hoac Cho them da lanh vao be ehda nude de thap nhiet dp nude - Be tdng can dupe van chuyen nhanh td may trdn den khudn van 68 iSIWnHi^l 6.2009 Toan bd dam ngang doe cau cang va ban mat cau deu diing may dam rung theo each c i m vao, theo phuong phap cam nhanh va riit cham, de be mat ciia mdi mot vj tri khdng ndi bpt v i khdng bj liin, bing phing, cd vda ndi len Khdng dupe de sot vj tri khdng dam (dac biet la nhdng vj tri d gdc, canh), de tranh hien tupng rdi rac, td ong va san siii; Tuy nhien khdng nen dam qua nhieu dan den hien tUpng phan ly, tiet nude khien be mat be tdng hinh nhdng ndt v i n Khdng nen dat miy dam tren thep de tranh anh hudng den chat lUpng be tdng da b i t dau ddng ket phia dUdi Cung khdng de may dam len tren buldng keo, tranh cho buldng bj chan ddng lam gian nd cdp pha 2.5 Sda ehda khuyet tat va bao dudng pham: - Sda ehda khuyet tat Sau dd bd cdp pha, be tdng da ngUng ket hinh neu edn khuyet tat thi phai nhanh ehdng sda ehda Viing ria khu vUe sda ehda phai diing cdng eu due nham xd ly saeh se Diing da danh bdng hoac mai nhin nhdng chd Idi 16m de phii hop vdi tieu chuan F2 pham vi yeu cau dung sai ciia quy djnh Phai c i t bd nhdng khu vUc ket cau td ong, neu can thiet nen tang dd sau vet cit, nhung phii tranh khdng de Id phan thep ngoai Sau dd bd cdp pha be tdng mat ben cau kien, kjp thdi tudi nude lam Ucfft ddi vdi phan be tdng bj Id ngoai, sau diing nildng mdng phii len de bao dudng Ketluan: Dudi sU giam sat chat che ciia ky sUtU van qude te ESBI, chat lUpng thi edng be tdng cdng trinh chii the cua du an cau cang nha may Nhiet dien Hai Phdng phii hpp vdi tieu chuan ITB ciia chu dau tU, dat den yeu cau ciia be tdng my thuat The hien dupe chat lupng rd ret ciia be tdng my thuat Thdng qua viec thi edng be tdng my thuat phan chinh cau cang, ehiing tdi da tdng ket dupe nhdng loi thudng gap tdn tai thi edng be tdng my thuat va tich luy dupe mdt sd bien phap khdng che va du phdng thi edng be tdng my thuat, gdp phan lam phong phii kinh nghiem thi edng va cac bien phap khdng che thi edng be tdng my thuat sau • TAI LIEU THAM KHAO Fu Li Rong WPP Thi cdng betdng Cdng trinh Cau cang Nha may Nhiet dien Hai Phdng Viet Nam Thang n/2007 JTJ268-96 Quy pham thi cdng betdng cdng trinh thuyvan,Thang 10/1996 Tai lieu mdi thau Ou an nha may Nhiet dien Hai Phdng (ITB) Cdng trinh phan thd Quy pham nghiem thu chat luong thi cdng cdng trinh ke't cau betdng GB50204-2002, Nha xuat ban cong nghiep xay dung Trung Quoc TIN XAY DITNG TIN XAY DCrNtTTIN XAY D l / N G TIN XAY Dl/NG TIN X A Y D l / N G VAN BAN QPPL DA BAN HANH • Nghj djnh sd 42/2009/NO-CP 07/05/2009 ciia Chinh phii ve phan loai dd thj • Quyet djnh sd 532/QO-TTg 27/4/2009 ciia Thii tudng Chinh phii phe duyet nhiem vu quy hoach chung xay dung khu kinh te cda khau Odng Oang - Lang son, tinh Lang Son den nam 2030 • Quyet Oinh sd 605/C2O-TTg 13/5/2009 ciia Thii tudng Chinh phii bd sung vdn dU toan nam 2009 ciia Bp xay dung thUe hien nhiem vu tU van lap quy hoach chung xay dUng thii dd Ha Ndi den nam 2030 va tam nhin 2050 • Quyet djnh sd 616/QO-TTg ciia Thii tUdng Chinh phii ve viec cdng nhan TP Hai Duong, tinh Hai Duong la d6 thj loai true thupe tinh Hai Duong • Quyet djnh so 699/QO-TTg ciia Thii tUdng Chinh phii phe duyet nhiem vu quy hoach xay dung he thdng cae trudng dai hpe, cao dang tai viing TP Hd Chi Minh den nam 2025, tam nhin 2050 • Quyet djnh sd 700/ QO- TTg 02/6/ 2009 ciia Thii tudng Chinh phii phe duyet nhiem vu quy hoach xay dung he thdng cac trUdng dai hpe, cao ding tai viing thii dd Ha Noi den nam 2025 va tam nhin den 2050 106,6% so vdi eiing ky nam 2008 San xuat cong nghiep va VLXD • Gia trj san xuat edng nghiep va VLXD ciia cae don vi thude Bd (ke ca TCty edng nghiep Xi mang VN) Udc thue hien thang dat 3.291 ty dong, thang dau nam dat khoang 14.097 ty ddng bing 34,6°b ke hoach nam, bing 96,7% so vdi eiing ky nam 2008 • Xi mang: toan nganh sin xuat thang dat 4,08 trieu tan, thang dau nam khoang 18,32 trieu tan, dat 41,6% ke hoach nam BpTRl/6NG TIEP DOAN DAI BIEU BO NONG NGHIEP CUBA VAN BAN QPPL BAN HANH THEO THAM QUYEN • Thdng tU lien tjeh sd 08/2009/TTLT-BXD-BTCBKHOT-BNNPTNT-NHNN 19/5/2009 ciia eae Bd: Xay dung, Tai chinh, Ke hoach dau tu, Ndng nghiep phat trien ndng thdn, Ngan hang nha nudc Viet Nam hudng dan thUe hien Quyet djnh sd 167/2008/QO-TTg 12/12/2008 ciia Thii tudng Chinh phii ve chinh saeh hd trp hp ngheo ve nha d • Thdng tUsd09/2009/TT-BXD 21/5/2009 ciia Bd Xay dung quy djnh ehi tiet thuc hien mdt sd ndi dung ciia Nghi djnh s6 88/2007/NO-CP 28/5/2007 ciia Chinh phii ve thoat nude dd thj va khu edng nghiep SAN XUAT KINH DOANH Gia tri san xuat kinh doanh ciia cae don vj thupe B6 Udc thuc hien thang dat 9.816 ty ddng, Sthang dau nam dat khoang 41.398 ty ddng, bing 34,9% ke hoach nam, bang 100% so vdi cung ky nam ngoai Xay l i p • Gia trj xay lap ciia eae don vj thude Bd Udc thue hien thang dat 4.665 ty ddng, thang dau nam khoang 18.919 ty ddng, dat 36% ke hoach nam va bing Sang 17/6/2009, Ooan dai bieu Bd Ndng nghiep Cu Ba Thd trudng Juan Perez Lamas dan dau da den tham va lam viec vdi Bd Xay dung Dong ehi Nguyen Hong Quan - Uy vien Trung uong Oang, Bp trudng Bp Xay dung - ddng Chii tjeh Uy ban Lien Chinh phii Viet Nam - Cu Ba da than mat tiep doan Bp trudng Nguyen Hdng Quan nhiet liet chao mdng dong ehi Thu trUdng Juan Perez Lamas va eae vien doan da den tham va lam viec vdi Bp Xay dung; danh gia cao cae chuyen tham, lam viec va trao ddi gida eae eo quan Chinh phii ciia hai nudc Viet Nam - Cu Ba va cho biet, phien hpp thd 27 ciia Uy ban Lien Chinh phii Viet Nam -Cu Ba dien tai La Habana sip tdi, Uy ban se ban them ve cic ndi dung hpp tac nhim muc tieu sau mdt sd nam Cu Ba cd the tu tiic duqc luong thUe Tai budi tiep va lam viec, Thd trudng Bp Ndng nghiep Cu Ba Juan Perez Lamas da cam on Bp trudng Nguyen Hdng Quan da danh thdi gian tiep doan va bao cao vdi Bp trudng nhdng ndi dung chinh da lam viee vdi Bd Ndng nghiep va Phat trien ndng thdn Viet Nam ve Chuong trinh hpp tac song phuong thue day phat trien nen san xuat ndng nghiep eiia Cu Ba, dd cd cac du an hop tac cu the giUa hai Bd i:^VklT1^T 6.2009 69