Cc h vn khun mi ca hng DOKA s dng cho thi cng b tng cc cng trnh ni ting M

1. Thi cng cy cu cp u tin Maine, M trn vn khun DOKA

Cy cu cp u tin Maine ang c xy dng bi Cng ty Cianbro, Reed LLC trn h vn khun DOKA thi cng cc ct thp cao 420 feet (ct thp cu c cao 235 feet). Cu mi s bc qua sng Penobscot v thay cho cu c Waldo-Hancock hin nay.

Cy cu b tng cp mi c nhp chnh di 1.161 feet ang c thi cng trn tuyn ng s 1 Maine, b bin pha ng nc M, gn khu di tch lch s Fort Knox. Cy cu c thi cng bi cng ty lin doanh gia Cianbro Corp ca Pittsfield Maine v Reed & Reed ca Woolwich Maine, ch u t l Cc Qun l giao thng Maine.

Cu mi ang thi cng s bc qua sng Penobscot thay cho cu c Waldo-Hancock

Ct thp pha di

C 2 ct thp s c thi cng cng mt thi gian. Phn ct thp pha di sn cu cu to gm 2 chn hnh ch C, cao ti gn 124 feet. Sut qu trnh thi cng cc ct thp thp hn, cc nh thu s dng gn 5300 ft vung vn khun dm g DOKA kiu Top 50 kt hp vi cn cu nng h khun leo DOKA kiu MF 240. 8 m b tng cho mi chn cu, s dng tng cng 3000 yad khi b tng cng cao cho 4 chn cu, tin hnh mi m thng cao 15 feet 6 inch. H vn khun Top 50 c la chn do chng rt linh ng p ng mi yu cu ca cng vic. Ch s dng mt s t cc chi tit tiu chun n gin v nhanh ph hp vi cc yu cu v chiu cao, chiu rng, p lc ca b tng, v v p kin trc ca kt cu b tng. Theo cc nh thu, chi tit quan trng nht i vi cng trnh ny l d dng to ra phng ca mt vn khun bng g dn.

Ct thp pha trn

Cc ct thp pha trn cao 296 feet hnh vung, rng 14 feet 3 inch, thon theo cnh di hn t 35 feet 3 inch di y ti 26 feet 8 inch trn nh. i vi cc ct thp bn trn, DOKA

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li cung cp h khun leo MF240 v 4.900 ft vung vn khun Top 50 c lp t., c nng cp vi h gin c bit nhm hn ch cc mi ni t vn khun i vi cc m b tng cao ti 15 feet 6 inch.

Tit kim lao ng

Phng n nng cp h vn khun tiu chun Top 50 vi h gin tit kim kim cho nh thu vic lp t gn 320 mi ni t i vi mi 18 ln nng. Tng s gm 5760 mi ni t, tit kim c chi ph lao ng ng k cho nh thu, khin cho h Top 50 tr thnh h vn khun kinh t nht dnh cho cng vic y thch thc ny. H khun leo MF240 cho php tho d, lm sch v chun b vn khun s dng li ti ch. Cn cu ch nng vn khun ln cp tip theo. Mi thao tc ch mt mt na ngy lao ng. Mi m in hnh cho ct thp pha trn cao ti 15 feet 6 inch v b tng c theo chu trnh tun. Cc sn thao tc ca MF240 rng 8 feet to cho cng nhn mt khng gian hot ng tt tng an ton cn thit khi lm vic cao hng trm feet.

Nng cp h vn khun tiu chun Top 50 vi gin tit kim cho nh thu lp t gn 320 mi ni t i vi mi 18 ln nng

Lp t cp treo

Do tin thi cng eo hp m cc cp chu lc s c lp t khi ang thi cng cc on trn ca ct thp. Do thi gian cu v li vo b hn ch, nn i hi p dng gii php t leo(self-climbing) , cho php li vo gn ti khung lng cp, trong khi neo xung quanh cc cp chu lc lp t t trc. Nh thu chn h khun leo SKE 50 ca DOKA kt hp vi cc sn thao tc ng lng.

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Cc sn thao tc chnh c lp t sn bi DOKA M ti chi nhnh ca h New Jersey. Thit b t leo SKE c kh nng cht ti cao, cho php thi cng cc vn khun nng cha cc cng c v vt liu. Cc nhn vin k thut dch v ca DOKA M gip cho cc nh thu nm bt c cch s dng h thng nh th no. Thi hn hon thnh vo nm 2007, cu s c 2 ln ng xe chy rng 11 feet v ln ng a chc nng rng 7 feet dng cho ngi i b v xe p. Trn nh ca mt trong cc ct thp c i quan st cao 40 feet dnh cho cc khch du lch quan st c ton cnh ca khu vc.

2. H vn khun nh mi Frami s dng thnh cng trn th trng M

Frami l h vn khun mi (kch thc tnh ra feet v inch) ca DOKA dnh cho th trng M, c c im l nhng panel chiu cao 9, 6 v 3 feet. H vn khun nh mi nhanh chng gt hi thnh cng i vi cc nh thu M.

Frami l h vn khun nh c thit k thnh cc theo h logic nhm to hnh nhanh v kinh t cc mng nh v din tch nh. H ny c th dng thi cng cc tng, ct v l l tng i vi cc dm v tm mng v cho php cc i th thi cng bng tay. Cc tng cao 9 feet c th c to hnh bng 1 panel v ton b phn trn lng vi 2 mi ni mi panel. Ni cc panel nhanh c bo m bng 3 kp nh ca Frami, cn cho mi mi ni thng ng 9 feet, mi mi ni cng cn mt ba n g v chnh cc panel.

H vn khun mi Frami dng thi cng cc tng cao bng phng

S kt hp gia chiu cao v chiu rng khin cho h vn khun Frami tr ln hon ho khi s dng. Tt c cc panel u c trang b cc tay vn nhm p ng nhng yu cu v an ton lao ng. Cc khung ca panel Frami c ch to t thp hnh hp rng, c m in nng c bn trong ln ngoi nhm m bo tui th lu di. Vi h vn khun panel a nng Frami c th to hnh c cc gc v cc ct c s dng g 2 inch. Kch thc ct c th to hnh ti 36 x 36 inch. H vn khun ny cho php dng i vi p lc ca b tng ti ln ti 1650 psf trong thi cng ct. Vi panel c tr b tng, cc nh

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thu c th to hnh cc tr b tng ti 24 inch trong s gia 2 inch m khng cn neo ging. S a dng kch thc v c kh nng s dng panel theo phng thng ng v nm ngang, kt hp vi cc ph tng mi, khin cho h vn khun Frami tr ln l tng i vi cc dm v m mng.

S dng thnh cng h Frami mi cho hng Ford

H Frami mi c Cng ty xy dng Rudolph Libbe s dng thnh cng trong vic ci to nh my lp rp ca hng Ford Avon Lake, bang Ohio.

Ford ang ci to ton b 3,7 triu ft vung din tch xng lp rp t Avon Lake, Ohio, nhm xy dng mt dy chuyn sinh thi (Econoline). Cng vic gm 1 dy chuyn sn xut vi trn 16 h sa cha. Rudolph Libbe chn h vn khun Frami ca DOKA, v y l h khun nh thit k c o cho php vn chuyn v lp t bng tay. H vn khun ny hn ch vic s dng cn cu, cho php tt c mi cng vic c thc hin di mt mi nh.

H vn khun Frami dng thi cng ci to nh xng hng Ford

Rudolph Libbe coi y l u im ch yu ca h vn khun ny trong qu trnh thi cng. Mt u im khc ca h Frami l mt chng loi rng kch thc chiu cao v rng ca panel. Rudolph Libbe cn c 20.000 ft vung vn khun c chiu cao thay i t 2 feet n 10 feet. Mt m trung bnh di 200 feet v 60 yad khi b tng. Rudolph Libbe c cc i th a ngnh gm 3 th mc, 1 i trng, 1 th v 1 ngi iu khin my nng ng lng. Mi i lm vic theo ca 12 gi, 7 ngy mi tun, cung cp trn gi b tng vt tin 2 tun. Vn khun Frami s dng ti i hc Washington

Cng ty Ceco tin hnh thi cng gara t 6 tng ti i hc Washington bng h vn khun Frami. Gara t phc v cho 13.300 sinh vin v 3.000 cn b nhn vin v gio vin ca trng. Ceco ng k s dng gn 3.000 ft vung vn khun Frami mi ca DOKA thi cng d n ny.

Gara ang c xy dng nm v tr xy dng dy gia tuyn ng ng c v tuyn ng st Metroliner, khin cho vic thi cng gp nhiu kh khn. Trong hp ng gm c cc tng dc thoai thoi, cc ct kch thc khc nhau v cc tng mng. Do cao ca

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tng thay i t 6 feet n 15 feet v cc ct cao ti 18 feet, nn h vn khun mi Frami tnh theo inch v foot kt hp vi cc kch thc c th to ra mt gii php hon ho. Vn khun lp t nhanh v cho cht lng hon thin tt, l iu quan trng i vi d n. Cng ty Ceco l nh thu ph vn khun ln nht M, ang thi cng trn 200 d n, gm hn 70 triu ft vung mi nm.

Cc c l h logic to ra cc n v nng cu nh v nhanh v rt ngn thi gian cu

3. H vn khun Framax Xlife to ra s khi u tt p M

Nh thu Pizzagalli a vo s dng h vn khun Framax Xlife cho cc d n tr gi nhiu triu USD cc bang Bc Carolina, Georgia v Virginia. Framax Xlife to ra b mt hon thit tt nht. Cc panel g dn ca h vn khun ny c ph mt lp nha trn c hai mt, m bo cho hon thin b tng phng. Lp nha ny cng ko di tui th ca g dn. H vn khun ny t phi sa cha. Ba d n nng cp ca Pizzagalli s lm tng cng sut x l nc/nc thi ti Bc Carolina, Georgia v Virginia.Tng gi tr ca 3 d n ny ln trn 150 triu USD v bao gm cc cng trnh b tng a chc nng vi cc m b tng tng lun thay i. Nhu cu vn khun c bit cao d n Broad Run, cn ti 14.000 ft vung (1.299 mt vung) vn khun Framax Xlife.

Cc i thi cng trn c 3 cng trnh ny nhn thy vn khun Framax Xlife cho b mt b tng p sau khi d khun.

H vn khun tng mi Framax Xlife ca hng DOKA

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4. Thi cng cc tr cu mi qua sng Susquehanna vt tin nhiu thng bng h vn khun DOKA

C hai cy cu gm c 2 tng chng v 39 tr. Mi tr gm c 2 cc khoan nhi b tng, i b tng, on thp b tng cng, on thp b tng rng v m tr cu bng b tng.

Vn khun thp thi cng m tr cu

Nh thu G.A & F.C Wagman l i tc lin doanh c trch nhim thi cng cc kt cu bn trn mt t, cn h vn khun i vi cc tr cu hnh van kch thc 8 feet x 12 feet, vi yu cu phi m bo tin thi cng. quyt nh s dng vn khun DOKA. DOKA thit k, ch to v cung cp hn 300 nghn lbs vn khun thp thng phm trong thi gian 3 thng.

Chiu cao cc tr cu dao ng t 20 feet n 74 feet. Cc tr thp rng 20 feet c bng 1 m b tng. i vi cc tr cao hn, gia 20-74 feet thng lm 2 m: m u on tr c, m th 2 on tr rng.

DOKA thit k mt khun thy lc c bit c th lt c thi cng bn trong cc tr rng, v rng bn trong qu nh c th cho php lt khun bng phng php thng thng. n thng 9/2006 s c 40 tr trong s 78 tr cu s hon thnh. Xng thit k ca Cng ty Wagman chu trch nhim v thit k khun m bo tin cho thi cng cc tr cu.

5. S dng vn khun Dokaflex thi cng Trung tm Hu tr Madison, bang Wisconsin

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Nh thu Vogel Bros ang thi cng Trung tm Hu tr mi cao 8 tng Madison. Cng trnh ny gm cc cn h c lp dng cho nhng ngi ngh hu tui cao, d kin s c hon thnh vo cui nm 2006.

Cng trnh cao 8 tng b tng d ng lc ko sau, nh khung b tng c gara t ngm cao 2 tng. Vogel Bros chn h vn khun Dokaflex to hnh cc sn trn tt c cc tng. H vn khun ny to ra chu trnh thi cng nhanh i vi mi sn. H vn khun ny n gin v hiu qu, khng cn ging v khng cn di chuyn vn khun, gim c lao ng nh c h rng rc nng. H vn khun Dokaflex gm c 3 b phn chnh: vn khun g dn HDO dy 3/4 inch, cc dm g H20 v cc ct chng sn Eurex 30-h vn khun sn Dokaflex cho php d dng kim tra cc chi tit v gim c s c trn cng trng. Tt c i hi phi chuyn sang s dng h Dokaflex c cc u ni nhanh v cc im ni dm vi dm.

Tng cng Vogel Bros lp t v tho d 31.000 ft vung vn khun Dokaflex v b tng y din tch mi sn. Hai i thi cng nh gm 3-4 ngi mi i lp v tho d cc vn khun .

Hng DOKA M m bo dch v trn cng trng p ng tin ca d n, hng dn thc hin cho i ng ca nh thu Vogel Bros.

S dng vn khun Dokaflex thi cng cc sn tt c cc tng Trung tm Hu tr Madison

inh B L

(Ngun tin: Theo T/C Concrete Construction, N1/2006)

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