Bin phi thi cng cng trnh t mng n hon thin

I. Cng tc chun b a. nhn mt bng cng trnh, ct mc cng trnh (c bn v v d ton nh km theo cng trnh), cos cao cng trnh ( phn ny ti s ni r hn vi l phn quan trng). b. dn dp mt bng ( c, cy, cc vt dng.....), ng ln tri b vt t v cng nhn ngh li cng trnh, trng hp nh dn dng hai bn l vch nh th sn trc tim ct vo hai vch nh mn lm chun, trng hp cng trnh rng hn th ng gabarie lm tim chun cho bc ct. c. ly gc chun cho nh chun b xy dng thng ta p dng bnh phng hai cnh huyn nhn cho cnh cn li ( khng bit ng khng na) thng thng th vy: - ly mt cnh nh lm chun sau ging dy nh theo phng trc dc ca nh ti hai im ny ng gabarie sn, tip theo ging dy nh theo trc ngang nh bt u ly gc vung nh theo cch sau: mt trc ta ly chiu di ca thc o l 1,9m;3,1m v trc kia ta ly chiu di l: 2,5m;4,1m v ging cho hai im li ta c cc kch thc sau : 3m;5m ( thng thng ly gc ta phi b bt 10cm ca thc bi v 10cm u ca thc khng chnh xc nhiu) - tip theo l ly trc ngang, dc ca cng trnh theo hai phng ly gc t ta ng gabarie vo cc v tr, sau ny hon thin ta cng cn ti n. Huy ng thit b phc v thi cng: +Cng tc thi cng t: Thi cng c gii kt hp th cng. D kin huy ng xe my cc loi sau: Xe o bnh hi hiu SAMSUNG, SOLAR (KOREA). Xe xc t hiu KOMATSU. My bm nc. My m bn, m di. +Cng tc b tng: Dng b tng ti, c ch t nh my sn xut b tng n khi gi in t hng, loi xe b tng c dung tch 6m3. My m di, bn, my ct un st, khoan. My lm mt b tng. + Cng tc coffa ct thp: S dng cc thit b sau: H thng coffa g kt hp coffa thp nh hnh. Dng puli cu lp . My ct, un ct thp. My hn in. My ca khoan (BOSCH). Thit b cm tay (bt vt, bn inh) bng hi v bng in. Vn khun v ging chng phi m bo: n nh khng bin hnh, cng v bn. Chu c trng lc v p lc mt bn ca b tng mi cng nh cc lc xut hin trong qu trnh thi cng. m bo kch thc v hnh dng chnh xc, m bo ng v tr so vi cc b phn ca cng trnh ang thc hin. + Cng tc hon thin: My trn va. My Nivo. My ca, mi hiu BOSCH. My phun sn. My ct gch (kh, nc) hiu HITACHI. My nh bng nn. +Cng tc mc, vn khun g: My lin hp. My bo tay. My ca tay. + Cng tc in nc: Khoan in cm tay, my o in tr t. +Thit b trc c, kim tra cht lng cng trnh: Thit b th nghim ti hin trng. B dng c kim tra st b tng.

Dng c o m ca ct. Thng hay vt liu khc ct gi cc mu ct liu, cement. ng o 100ml, nhit k. 1 my kinh v Leica TC600 (Thy S), 1 my kinh v NIKON (Nht), 1 my thy bnh LeiCa 820 (Thy S), my thy chun, sng bn b tng. Khun ly mu b tng theo tiu chun. Thit b kim tra cng thp, b tng, mc va ti phng th nghim. 1. Cng tc chun b thi cng: i n gia on thi cng ca cng trnh th vic chun b cc s liu v k thut, x hi l mt cng tc rt quan trng, n nh hng trc tip n tin , cht lng v i sng ca cn b, cng nhn thi cng cng trng sau ny. + Cc cng vic cn chun b: Mt ct a cht cng trnh, tnh cht c l ca cc lp t, ca nn v a cht thy vn. Kh nng vn chuyn thit b my mc c gii n cng trng sao cho an ton v kinh t nht. Cc ngun vt t cung cp cho cng trnh. Ngun in nc phc v cho thi cng v phc v cho sinh hot ca cn b, cng nhn thi cng cng trnh. Nhng qui nh chung ni cng trnh xy dng. Chun b h s php l: Sau khi c thng bo trng thu s tin hnh ngay cc th tc php l: + Thng tho i n k kt hp ng kinh t giao nhn thu xy lp. + Nhn bn giao mt bng, ct mc, cao chun. + Lin h vi chnh quyn a phng lm th tc cn thit a cng nhn, thit b thi cng, vt t n cng trng. Mt khc, kt hp vi a phng trong cng tc bo v, phng chng chy n v v sinh mi trng. + K kt cc hp ng kinh t, hp ng mua bn cung cp vt t v nhanh chng tp kt ti cng trng. Nghin cu k h s: Nghin cu li ton b bn v thit k k thut. So snh cc bin php t chc thi cng sao cho tit kim thi gian v t hiu qu, m bo cht lng cng trnh hp l nht v tin hnh lm bng tin thi cng chi tit tng hng mc cng trnh c th, b tr cn b, cng nhn ph hp thi cng lin tc. Cng trong thi gian ny chng ta s chun b k kt cc hp ng cung cp vt t thit b cn thit. 2. Mt bng t chc thi cng: - Mt bng cng trnh nm trn ng nh Phong Ph, do vt liu, my mc thit b c vn chuyn ch yu trn tuyn ng ny. - Hin ti xung quanh khu vc mt xy dng cha cao, xung quanh c ng trnh tng i trng v c ng giao thng ni b i ngang cng trnh. - Cc cng tc gia cng lp dng nh thp, vn khun c thc hin ngay cnh cng trng. Tn dng phn t trng ca cng trnh. - Cc bi cha vt liu st thp nm gc cng trnh, coffa g, coffa nha c phn theo chng loi ring cha tng bi ring bit. - Ngun in phc v thi cng cho cng trnh c s dng t trm c lp t trn cng trnh. - Ngun nc phc v thi cng cng trnh s dng ngun nc hin c a phng. 3. S t chc thi cng: - S t chc thi cng c b tr ph hp vi c im cng trnh trnh ca cn b nhm m bo cho cng trnh thi cng ng tin , t cht lng. - S t chc hin trng thi cng gm 3 b phn: + B phn ch huy chung ti tr s. B phn ch huy ti cng trnh. B phn thi cng trc tip. Mi quan h gia tr s chnh v vic qun l ti cng trng: B phn ch huy ti tr s v s ch huy ti hin trng thng xuyn ch o, bn bc, trao i t chc thi cng ti cng trng bng cc bui hp giao ban hng tun ti hin trng. Cc phng ban ti tr s chnh thng xuyn kim tra v gip ban ch huy cng trng gii quyt mi vng mc v khi lng, vt t, my mc, thit b.

Vai tr ca ban ch huy cng trng: + T chc ti cng trng bao gm : 01 ch huy trng cng trnh v 01 ch huy ph ti cng trnh, ch huy trng l ngi trc tip iu hnh thi cng chung ti hin trng v ch huy ph l ngi thay th khi ch huy trng vng mt. + Ban ch huy cng trng ton quyn gii quyt mi vn trn cng trng v chu trch nhim trc Cng ty v mi quyt nh ca mnh. Cc trng b phn phi chu trch nhim trc ban ch huy cng trng v mi vn ca bp hn mnh ph trch v nhn lnh trc tip t ban ch huy cng trng +Ban ch huy cng trng ca cng ty c giao ton quyn qun l, gii quyt mi vn lin quan n cng tc v sinh mi trng v thc hin cc th tc php l vi cc c quan chnh quyn s ti, vi ban qun l bn A v vi ngi lao ng. +Ban ch huy cng trng lp ra cc bin php bo m v sinh mi trng ni thi cng v khu vc ln cn, nh bin php che chn, chng bi, chng khi, chng n, gy nhim, s dng my mc, thit b ph hp, tun theo cc qui nh ca Nh nc v ch s ting n, khi +Ban ch huy cng trng s t chc cho mt nhm lao ng phc v cho cng tc v sinh mi trng. B phn ny s trc tip thc hin cc cng vic nh qut dn v sinh cng trng v khu vc ln cn, ti nc chng bi, thu gom rc trong thi cng +Ban ch huy cng trng c nhim v gio dc thc chp hnh cc qui nh v v sinh, bo v mi trng cho lc lng cn b, nhn vin, cng nhn tham gia ti cng trng thng qua cc hot ng sinh hot, lao ng hng ngy, cc cuc hp giao ban gia ban ch huy vi i trng thi cng. Vai tr gim st k thut ti cng trng: + B phn gim st k thut c chuyn mn v trnh nghip v ca cng ty c thnh lp v hot ng rt c hiu qu trong vic qun l, kim tra cht lng sn phm xy dng. B phn gim st k thut ny c b tr ngay ti hin trng t khi cng trnh bt u thi cng. + B phn ny c quyn v trch nhim kim tra cht lng vt liu, cht lng bn thnh phm, cht lng thi cng cng trnh theo ng quy trnh th nghim kim tra. Mi cng tc u c b phn ny kim tra, nghim thu trc khi mi gim st k thut nghim thu. B phn ny c quyn t chi mi vt liu khng t yu cu v cht lng chng loi. Cc b phn xy dng cng trnh: + Cc b phn phc v: k thut ca cc n v thi cng, vt t, hnh chnh, an ton lao ng, trc t, kho c iu hnh trc tip bi ch huy trng v ch huy ph cng trnh. + Cc i thi cng gm: i ct thp, i coffa, i b tng, i hon thin, i in, i nc, i phc v thi cng trc tip ti cng trng c lnh o bi nhng k s giu kinh nghim chu trch nhim t chc thi cng theo chc nng c giao ca i di s ch huy trc tip ca ch huy trng cng trnh. 4. Cng tc trc c: + nh v cng trnh xy dng trong phm vi khu t: * Cng trnh l nh chung c cho cc s. S lin quan gia cc cu kin cc b phn rt cht ch nn cng tc trc c cc k quan trng. Cng tc trc c gip vic thi cng c chnh xc v mt kch thc ca cng trnh, m bo thng ng, nm ngang ca kt cu, xc nh ng v tr cu kin, h thng k thutn loi tr n mc ti thiu cc sai s v tim ct, v tr trong thi cng. *Cn c theo cc mc bn giao ca n v thit k. Da vo cc li trc chun trn mt bng neo vo cc vt c nh. Cc mc ny c bo qun gm tt c cc cng vic xc nh, cao cho tng hng mc, cc chi tit thi cng, t vic lp t coffa cho n cc cng tc hon thin thc hin giai on cui cng trnh. + Lp li trc to trc c: * Lui trc c c lp da vo cc trc ca cng trnh theo thit k. y l cng tc quan trng, m bo cng trnh c b tr, kch thc v thng ng. Cc li trc ca tng trn c lp trn c s li xut pht t tng trt, cc im ny c chuyn ln cc tng trn theo phng php chuyn thng ng. + Chuyn cao ln tng bng thc thp o trc tip theo mp tng, mp ct vi sai lch l 3mm, s dng my thy bnh t ng trong thi cng thng nht v thun li cho vic thi cng cc cu kin, chi tit trn tng cao c dch +1000 so vi cao hon thin

c nh li bng sn ti tng, vch, ct. + Lp li quan st: + Cc bc ca cng tc trc c v cc yu cu k thut s c cng ty tun th theo qui nh tiu chun Vit Nam 3972-85 c th nh sau: khi nhn c tim mc ca ch u t, s xc nh tim mc trn mt bng. V tr cc tim mc c bo v bng cch b tng c ro chn m bo khng b m, b mt trong qu trnh thi cng. + Li khng ch thi cng c b tr thun tin theo cc trc trn bn v m bo cho vic thi cng c bo v lu di m bo chnh xc cao. + Cc mc o ln c b tr khong cch m bo n nh v bo v trong sut qu trnh thi cng. Khong cch cc mc quan trc ln s c thc hin mt tun trn mt ln c ch n im gia ti nh thm sn, xong phn xy cc bo co kt qu quan trc s c thc hin dng biu v hon thnh ngay trong ngy . Bo co c lp thnh 02 b gm cc thng tin sau: + Thi gian quan trc. + Tn ngi thc hin quan trc v ghi s liu. + L lch thit b o. + Mt bng v tr cc quan trc. + Cc s liu sau khi quan trc ti cc mc. + Cc ghi ch (nu c) ca nhn vin o c. + Ch k ca ngi thc hin quan trc, i din n v thi cng, BQLDA. Ton b kt qu s c trnh cho T vn gim st v lu gi trong h s nghim thu cc giai on thi cng, hon thnh cng trnh. + Cng ty s tin hnh trc c mt cch h thng, kt hp cht ch ng b vi tin thi cng. Cng tc o c c tin hnh thng xuyn trn cng trng, bao gm tt c cc cng vic xc nh v tr, cao cho cc hng mc, cc chi tit thi cng, t vic lp t coffa cho n cc cng vic hon thin thc hin giai on cui cng trnh. + Dng c quan trc gm cc my thuc ti sn cng ty. Tt c u trong tnh trng hot ng tt c th gm: + My kinh v theo 10B ca c. + My thy bnh ca c. PHN MNG + Do cng trnh l chung c nn phn mng cn phi c tnh ton k cn thn trn c s nghin cu nhng ti liu lin quan v a cht ca t v sc chu ti cng trnh. + Qua tnh ton, nghin cu s liu cng trnh a ra gii php mng b tng ct thp cho cng trnh l mt phng n hp l. + Mng b tng ct thp c gia cng thp, ngay ti cng trng. + Mng c ch to gm hai loi mng bng v mng n. Vn khun b tng mng dng vn khun g gia cng v lp dng. + V tr cc mng c xc nh v trnh by trn bn v c nh du trn mt bng cng trnh. + trnh lu lng nc ngm, tri ma lm cn tr qu trnh thi cng nn b tr nhng mng nh,h thu nc, my bm quanh chu vi h mng thot nc lm sch h mng. + o mng tng khu vc ca tng khi thnh mt h mng chung. Sau khi o t xong s tin hnh m nn y mng v b tng lt mng. + Cu to mng gm hai phn i mng v mng. Theo cu to trn phn khi mng thnh 02 t thi cng: t 1: thi cng b tng mng: + b tng lt mng 4x6, mc 100, dy 100, rng hn mng theo mi phng l 100. + bng th cng, dng m bn k, xc nh tim mng. + Thp dng lm v mng l thp 12a150 c buc thnh li sn ngoi, khi b tng mng th em vo lp t. + Mi ni gia thp c mng v thp v mng phi m bo 30d. Buc cc vin k vo ct thp theo yu cu lp bo v. + Cn chnh ct thp theo tim mng v c nh. + Lm thp i mng, mng. + Lp v hiu chnh ct thp i mng, mng. + Lp vn thnh mng, i mng, mng. + b tng i mng mng.

+ b tng mng mc # 250. + Lm v sinh lp ct thp, coffa v phn b tng lt mng. + B tng c trn bng my trn qu l. + Tin hnh b tng bng th cng n y king. + Dng m di m k b tng. - Bo dng b tng mng sau khi . + Tin hnh bo dng sau khi 1 bui. + Cho ngi ti nc ngy 4 ln trong mt tun. + Ph kn mt mng bng bao ti m bo m cho mng. + Tho d vn khun mng. + Sau khi b tng 01 ngy, tin hnh tho vn khun mng v c mng. Tho vn khun theo ng yu cu k thut trnh lm st m cu kin. t 2: Cng tc dm ging mng: Dm ging mng BTCT mc 200, c cc tit din sau: DK1(200 x 500); DK1a(200 x 300); DK2(200 x 300); DK3(100 x 300). + Gia cng lp dng ct thp + Ct dc v ct ai c gia cng xng theo kch thc thit k. + Thp c buc thnh khung v lp vo v tr. + Buc cc vin k dy 30mm vo ct thp m bo chiu dy lp b tng bo v ct thp. + Gia cng lp dng vn khun g. + Vn khun c gia cng v ng thnh hp tp kt li. + t vn khun vo v tr v iu chnh cho ng v tr thit k. + Sau khi iu chnh xong c nh vn khun bng cy g 3x5. + b tng mc 200. + Lm v sinh vn khun, ct thp. + Tin hnh nghim thu vn khun v ct thp dm ging mng. + Tin hnh trn v b tng. + m k bng m di. + Tho d vn khun + Sau khi b tng c 01 ngy tin hnh tho vn khun dm ging mng. + Tho vn khun theo ng yu cu k thut trnh lm st m cu kin. II. Thi cng a. o t mng cng trnh: Trong phn ny ta cn chun b nhng th nh sau: my o, xe vn chuyn t, cng nhn..... Trong phn ny ti xin nhc n cos cao cng trnh, theo ti khi i thi cng th ti c mt s kinh nghim nh sau: - nu cos cng trnh cao hn mt ng t nhin 0,45m th ta nn chn v tr ngay mp ng ( gi l b va) l cos -1,450 v dn ng nc hoc bn thu bnh vo n chn cng trnh l cos +1,000 t ta ly cos chun thi cng o t v chiu cao ca cng trnh. Trong phn trc ti gii thiu n Cos cng trnh nh th no ri hm nay tip theo l phn o t mng, hm t hoi, b cha chy..... Phn ny ty theo a th ca mi cng trnh m theo phng php ca mi k s cng trnh tnh ton lm sao mi tn tht nh nhn cng, vt t, ca my phi theo kp. Cn ch khi thi cng nh lin k cn phi c cc c gia c hai bn mng lin k m bo khng gy ln st mng nh k bn (phi i hu ta mt lm nha) phng php ny ti thng dng l dng vn thp nh hnh ng xung nn mng trc khi o t, sau mi thi cng o t. Trong cng tc o t ny ta nn kt hp lm mt s vic nh sn xut lp dng st mng, st c ct, st king. Trong phn sn xut lp dng thp cc bn nn ch tnh ton cn thn bi v ch sai mt t l i tong cy st khng lm n g c (b ri nn c kinh nghim) phn st ai th tnh ton cho ng vi tng s ai ct, dm v d: Ct c tit din l 200 x 300 khong cch bc ai l a 200 fi 6 th ta tnh ton nh sau: 200 x 300 = 1000cm => ct thp ai fi 6 l 150 x 250 = 800cm, bi v mnh phi tr lp b tng sau khi mi mt bn l 2,5cm, sau khi ta c chiu di ct mt cy thp ai fi 6 ta nhn s ai ln ri cho cng nhn ct ai, ch phi vit ln bng cho cng nhn lm ng, v phn thp cu to (thp gn) th cn ch hn i vi c

ct tnh ton sao cho khi b tng king xong th phi d theo D ca thp v d thp gn fi 18 x 30D =540 th ta phi cha st l 600cm t mp trn ca king sau ny ta cn ni thp ct ln sn na, v phn st dm th cn ch im ni st ti nhp th 1/4l nhp, ti gi th 2/3l nhp. Phn B Tng Trc khi sang phn b tng ti xin ni thm phn lp dng ct thp dm (), st ct, v st sn, th n phn coffa (vn khun), trong phn vn khun ta nn ch chn vn khun ng chng loi th trng hin nay c rt nhiu loi vn khun cho bn la chn ( vn p xi hai nc dt, vn khun nha xi vnh vin tin nhiu, vn khun thp xi tt nhng hay b cong vnh do va p) ty theo mi cng trnh m k s trng cng trnh la chn, cng trng ti hay la chn vn khun loi vn p (hnh con rng) loi ny c mt c im l nh d vn chuyn c th ct ni vo u ct hay u c, c nhiu loi cho bn la chn 20cm x 4m; 25cm x 4m;30cm x 4m..... vn sn th ti xi loi bng st 1m x 1m; 50cm x 1m.... cy gng th xi loi 5 x 5... v xi gin do chng cho sn (cn gi l gin treo) ci ny ngi Nam hay thi cng nht d lm m d cht cng nhiu... s b qua v coffa n phn b tng cho ct, dm, sn thng thng b tng cho ct th c mc (#) b tng cao bng sn, dm cc loi dm lanh t, vng cng vy phng php b tng bng tay c tnh nh sau: b tng #200 c cng thc tnh nh sau : nh mc vt t thao tiu chun 1,48 m3 ct, 1, 95 m3 , 0,7 xi mng, cn cng trng th c tnh nh sau cng thc : 4 ct, 6 , 1 bao xi, ci ny c phn tch nh sau: 4 ct c ngha l 4 thng B ct. THI CNG P T TN NN t c vn chuyn t im n v tr gn mt bng mng. Lm sn cng tc i qua h ging mng. Dng xe ra vn chuyn lp h mng t ngoi vo trong. Ti nc m k. PHN KHUNG I. CNG TC COFFA + Cng tc coffa l mt trong nhng khu quan trng quyt nh n cht lng b tng, hnh dng v kch thc ca kt cu. Coffa s dng cho cc cng tc phn thn l coffa thp v coffa g, coffa c phn loi v tp kt ring ti cc bi trn cng trng. Trc khi a vo s dng coffa c v sinh sch s v ph ln mt lp chng dnh. i vi coffa g cn ht sc cn thn trong ca x trnh lng ph v ch. + Coffa c gia cng, lp dng ngay ti cng trng. + Trc khi tho coffa, bn B mi gim st k thut bn A n nghim thu b mt ca cu kin. COFFA CT. + Coffa c dng l coffa g. + S dng cy chng g trn. ng knh cy chng t 8 10cm. + S dng nhng thanh g 5 x 10cm lm ging ngang v dc. b. COFFA DM, SN + Coffa dm, sn bng g. + Cy chng g trn. + Cng tc coffa c thc hin nh sau: + Chun b: - Bt mc xc nh v tr coffa. - B tr nhn lc ph hp, thc hin theo ng nhu cu cng vic. - V sinh mt bng ni s lp dng coffa. + Cng tc coffa c thc hin nh sau: Cn b k thut trc tip ch o cho cc t trng, ch chuyn mn thc hin cng tc coffa, m bo tht chnh xc theo yu cu k thut. Trnh tnh trng lp dng xong coffa phi tho d dng li do khng ng yu cu k thut. Tin hnh lp dng coffa theo bn v chi tit v ch dn ca cn b k thut. Coffa c lp dng phi vng chc, neo cht vo nhng im c nh, khng cho coffa b

x dch bin dng trong qu trnh b tng. V sinh coffa sch sau khi lp dng xong. Cn b k thut phi nghim thu cng tc coffa trc khi tin hnh cng tc tip theo. Coffa phi c ti nc v sinh trc khi b tng. LP DNG COFFA + Bo dng, bo v cng tc coffa. Coffa sau khi c lp dng xong nu cha c b tng th s c bo k trnh b x dch. II. CNG TC CT THP: + Ct thp c gia cng, lp dng ngay ti cng trng, c tin hnh theo tng cng vic, tng khu vc nh b ai, un thp, ct thp, ko thng thp thp c gia cng bng c th cng v bng my. My mc phc v cho cng tc ct thp trn cng trng v c nhiu loi nh my un, my ct, my ko thp + Thp a v cng trnh phi ng yu cu thit k mi c php s dng. Ct thp c dng c hai loi l thp gn v thp trn. Tit din c nhiu loi vi ng knh khc nhau nh 6, 8 ,10, 12 ,14, 16 ,18 vic s dng thp ng loi l tu thuc vo bn v thit k kt cu cng trnh. Khi gia cng thp trn phi b mc cn thp gn th khng b mc. + Ct thp c gia cng l thp ai, thp m, li thp + Ct thp trc khi s dng phi c sa thng, nh sch g thp, c th dng ba p thng hoc dng my un nn thng. Vi thp c ng knh di 20mm th ta c th ct un bng tay v nu ng knh ln hn 20mm th ta phi dng my. + Thp khi ct ra un phi xc nh thm dn di ca n, yu cu: ct thp b un gin ra thm 0,5d khi un gc 450, 1d khi un gc 900, 1,5d khi un gc 1800. on neo ct thp cng trng qui nh l 30d ct thp. Ni ct thp c hai dng l ni hn v ni bng km buc. + Chun b lp thp: B phn gia cng thp s thc hin ng bn v di s hng dn ca cn b k thut. Thp sau khi gia cng s c nh s theo ng chng loi v phn b ti ni cn lp dng. Tin hnh vch mc v tr lp thp. V dinh thp, dn dp mt bng v tr lp thp. Chun b cc ph kin, tp hp sn v tr lp thp nh cc k, km buc ng thi b tr nhn lc ph hp vi yu cu cng vic. + Thc hin cng tc ct thp: Tin hnh lp thp theo bn v kt cu di s hng dn ca cn b k thut. Ct thp sau khi lp dng phi m bo ng kch thc, ng s hiu thit k, ng v tr khong cch ca nhng thanh thp v im ni chiu di cc mi ni. Lu nhng v tr tip gip ca ct vi tng, ct vi lam phi t thp ch lin kt. Nu pht hin ra nhng sai lch so vi bn v thit k cn phi chnh sa li ngay nh lch st, qun hay thiu thp ch. S dng c kch thc theo yu cu m bo dy ca lp b tng bo v theo thit k nhm bo v cho thp chng li s tc ng ca mi trng xung quanh. Coffa phi c lp dng vng chc, khng xy ra tnh trng thp b x lch, chuyn v tr bin dng trong qu trnh m b tng. Sau khi lp dng ct thp xong phi dn v sing sch s, trnh khng tc ng mnh vo cu trc thp lp dng phng thp b x lch. Cn b k thut nghim thu ct thp sua khi lp dng xong khi mi tin hnh cng tc tip theo. Ngoi ra cng trng cn dng thp lm hng ro bo v an ton cho cng nhn lm vic v c hn vo cc cy chng st theo cc phng lm h ging vng chc. Ct thp sau khi lp dng xong, nu cha b tng phi c bo v k trnh vt nng ln gy x lch khng ng theo hnh dng, kch thc, v tr thit k. Trnh cc cht bn nh du m, bi bm dnh vo thp. Ct thp sau khi lp dng xong phi tin hnh b tng cng nhanh cng tt trnh cc iu kin bn ngoi thm nhp lm cho thp b g st. Sn phm b tng sau khi tho coffa nht thit khng c li thp. * Mt s lu trong cng tc ct thp: + Ct thp ct:

Do kch thc, tit din ca cng trnh ln nn ct thp ct khng c gia cng sn thnh khung thp m c ni tng thanh vo thp ch ct, sau mi lp dng thp ai v lp to thnh khung ngay ti v tr ct cn t thp. Di chn ct dng hai thanh thp hn cho gc nhau vi cc thanh thp gc ca khung thp c nh v tr ct, on trn mt t th dng thp C mc t hai cnh ca thp ai c bn mt nh vy m ct c nh v chnh xc. + Ct thp dm: c ghp thnh tng thanh theo yu cu kt cu theo nguyn tc ct thp pha trn ca dm ph nm trn ct thp dm chnh v ct thp pha trn ca dm chnh nm trn ct thp sn. Lp dng ct thp dm mp trn vn khun dm v khi lp xong ri mi h xung. + Ct thp sn: Ch t thp bin php (hn vo st sn) sau ny buc dy cp ko ct v chng trt cho cy chng trn sn. t cc k bo m lp bo v sn. II. CNG TC B TNG: Cng nh cng tc vn khun, ct thp th cng tc b tng cng gi vai tr quan trng trong thi cng. B tng s dng phi tun th theo TCVN. B tng c s dng l b tng thng phm c a n cng trnh bng xe trn, c a ln sn bng cu thp v mt xe bm ngang cng sut 80m3/gi d phng. Cht lng cc loi ct liu nh ct, , xi mng, ncthng xuyn c kim nghim theo TCVN. Cc th nghim s c lu gi np trnh ban qun l xt duyt. Bn sao v xi mng s dng trn xi mng s np trnh, trong nu r loi b tng c kim tra phn tch cht lng ti phng th nghim c chc nng c ban qun l chp thun, bo m ph hp vi yu cu s dng ca cng trnh. Cp phi b tng s dng cho cng trnh s c lp v np trnh ban qun l thit k ph duyt. Quy trnh b tng cho tng loi cu kin phi c gim st cht ch m bo t cht lng b tng cao nht. Cc dng c che nng, trnh mt nc nhanh, che ma, m b tng phi lun d phng sn. B tng phi m bo khng b r, khng b phn tng khi m b tng. + Thc hin cng tc b tng: - Tp hp cc s liu, h s, l lch ca ct liu s dng cho b tng (ct, , xi mng, thp) khi cc s liu c tp hp y , ng yu cu thit k th mi c s dng, thit k cp phi b tng theo yu cu ca kt cu cng trnh. Sau khi c thit k cp phi s ly mu th nghim hnh lp phng 15 x 15 x 15 bo dng mu theo quy trnh k thut sau tin hnh p mu kim tra cng b tng. - Ct thp, coffa phi c nghim thu trc khi b tng, xt n tt c cc lc tc dng (do my mc phc v cho vic b tng gy ra nh m di, ng bm) khi b tng vo thp v coffa phi m bo khng lm sai lch v tr thp hay gy n cho coffa lm cho cu kin b bin dng, sai lch so vi thit k ra. Trc khi phi kim tra k lng, kp thi bt kn cc khe h gia coffa vi nhau trnh tnh trng b tng chy nc bng giy bao thm nc, bng keokim tra cc cc k m bo lp bo v b tng. V sinh sch s phn bn trong v bn ngoi cu kin b tng khng st vt no trong ngoi cu kin v khi ri s khng ly ra c. - Vch ct cao , ct nn ca khi theo yu cu thit k. Chun b mt bng to khong khng thao tc, ng vn chuyn t ni trn n ni sao cho thun li nht, b tng c vn chuyn ti l lin tc khng c gin on nu khng s nh hng n cng cng nh lin kt ca b tng vi kt cu thp. - Chun b cc dng c, thit b b tng nh m b tng, xng xc, x ngnu cao phi chun b gin do nh khi ct trng hp vo ban m phi chun b h thng chiu sng phc v cho cng tc b tng. - B tr lc lng nhn cng, gim st k thut theo yu cu cng vic. + T chc cc nhm thc hin bao gm: - B phn hng dn ch o: gm cn b k thut, i trng i thi cng. B phn ch huy ny phi c mt tc trc khi b tng, kp thi pht hin v x l mi tnh hung xy ra trn cng trng. - Nhm kim tra: Kim tra li coffa, ct thp, km buc trc v trong khi .

- Nhm vn chuyn, b tng: b tng c chuyn ti v tr bng bm b tng hoc bng xe ct kt vn chuyn n. - Nhm hon thin b mt b tng: m bo sau khi b mt b tng ng cao thit k nhn phng hoc to dc cho b tng. Trong qu trnh b tng ch phi m di tht k cho b tng phn b u trong kt cu ( s dng m di my). - Vic b tng, hon thin b mt b tng s phi thc hin theo ng yu cu k thut i s ch o ca b phn hng dn. + Mt s lu trong cng tc b tng: - B tng ct: b tng ct dng b tng thng phm c trn sn mang n cng trng bng xe trn. T y b tng c cng nhn xc v th cng tng x b tng vo ct. B tr nhn lc gm ngi xc, ngi vn chuyn, ngi chuyn, ngi m di v ngi b tng. b tng trn ct cao th phi bt gin do. m bo phi hp nhp nhng mi thnh vin thc hin cng vic cho b tng vo ct c lin tc. cao b tng ct phi nh hn 1,5m do , ta phi cha l trn vn khun ct m bo ri ca b tng khi ct. Ch m di k cho b tng phn b u trong ct v trnh r mt b tng. Cc tng trn cao dng cn trc thp phn b b tng ct. - B tng dm, sn: do t im Thnh ph xe b tng ch c th vo ban m v vy cng tc b tng dm, sn c tin hnh vo ban m cho n sng. Dm, sn c ton khi sua khi nghim thu ct thp, ng in m trong sn, cc v tr t ng ncxe b tng c t ngoi cng trnh, c bm ln sn bng vi bm. B tr b tng trn sn gm hai ngi iu chnh vi bm, mt nhm dn b tng ra cho u v m di. b tng ti u th m di ti , b tng t trn cao xung ch su trc sau mi ch cn. Do sn rng nn khi b tng phi to rnh phn chia mt khi b mt ln thnh cc din tch nh hn . Ch b tng t gia ra hai bn. Ngoi ra cn b tng thnh b nc, thnh thang my, cu thang Khi thi cng b tng ct thp phi lm nhiu t, mch ngng gia cc t phi xc nh trc. V tr t mch ngng sao cho ni lc v tr tng i nh v phi vung gc vi phng truyn lc nn ca kt cu: i vi ct th mch ngng t ti v tr tip gip gia u ct vi mt di ca dm, i vi sn nm th t ti chn m ct, i vi dm xin mch ngng t ti chn dm xin, i vi cu trc mch ngng t ti vai cu trc hay pha trn cu trc, i vi dm, sn mch ngng t ngay di chn bn sn, sn khng sn th mch ngng t bt k v tr no min sao song song vi phng cnh ngn, sn c sn th mch ngng t nhp sn nm v pha bn phi. Ch x l mch ngng phi to nhm b mt ca mch ngng. + Bo dng tho d coffa: - Bo dng b tng giai on u s bt u ngay sau khi b mt b tng cng, khng b v v vic bo dng phi tin hnh lin tc trong 12 gi. - B mt b tng phi lun gi m bng cch ti nc ln hoc dng vt liu gi nc ph ln b mt gi cho b tng lun c m. - Ch c tho d coffa khi cng b tng t yu cu theo quy phm thi cng v nghim thu. Khi tho coffa khng c lm chn ng v rung nh hng kt cu b tng. Ngay sau khi tho coffa phi kim tra sa cha tt c cc khuyt tt nh v, nt, n. PHN HON THIN - CNG TC XY: + Do tnh cht cng trnh l dang khung b tng ct thp chu lc nn h tng ch mang tnh cht bao che ch yu, t tham gia chu lc, vt liu c dng khi xy tng l gch. Tuy nhin, cng cn phi tun th ba nguyn tc chnh khi xy gch l: + Gch xy tng hng phi phng mt, vung gc vi phng ca lc tc dng vo khi xy hoc gc nghing ca lc tc dng vo khi xy v phng vung gc vi khi xy phi