TIU CHUN XY DNG VIT NAM TCXDVN 309:2004 (Xut bn ln 1) CNG TC TRC A TRONG XY DNG CNG TRNH - YU CU CHUNG Surveying in construction. General requyrements Li ni u TiuchunTCXDVN309:2004Cngtctrcatrongxydngcngtrnh-Yucu chung quy nh cc yu cu k thut v o v bn a hnh t l ln v trc a cng trnh, cBXydngbanhnhtheoQuytnhs04/2005/Q-BXDngy10thng01nm 2005. CNG TC TRC A TRONG XY DNG CNG TRNH -YU CU CHUNG Surveying in construction.General requyrements 1. Phm vi p dng Tiu chun ny quy nh cc yu cu k thut v o v bn a hnh t l ln v trc a cng trnh, cung cp cc d liu chun xc dng trong thit k v thi cng xy lp, kim nh, gim st cht lng cc cng trnh xy dng. Tiu chun ny thay th cho TCVN 3972-85. 2. Tiu chun trch dn -TCXDVN271:2002.Quytrnhkthutxcnhlncngtrnhdndngvcng nghip bng phng php o cao hnh hc. -Tiuchunngnh:96TCN43-90.Quyphmovbnahnhtl1:500;1:1000; 1:2000; 1:5000; (phn ngoi tri). Tiuchunngnh96TCN42-90.Quyphmdovbnahnhtl1:500;1:1000; 1:2000; 1:5000; 1:10000; 1:25000; (phn trong nh). 3. K hiu dng trong tiu chun GPS H thng nh v ton cu; Sh S hiu chnh do cao mt t v mt chiu; mp Sai s trung phng v tr im; mH Sai s trung phng o cao; h Khong cao u ca ng ng mc; lch gii hn cho php; t H s c trng cho cp chnh xc; m Sai s trung phng ca mt i lng o; t Dung sai ca cng tc trc a; Xl Dung sai ca cng tc xy lp. 4. Quy nh chung 4.1. Cng tc trc a l mt khu cng vic quan trng trong ton b cc cng tc kho st, thit k, thi cng xy lp cng trnh trn mt bng xy dng. Chng phi c thc hin theo mt cng hoc phng n k thut c ph duyt v ph hp vi tin chung ca cc giai on kho st, thit k, xy lp, nh gi n nh v bo tr cng trnh 4.2. Cng tc trc a phc v xy dng cng trnh gm 3 giai on chnh: a) Cng tc kho st trc a - a hnh phc v thit k cng trnh, bao gm: thnh lp li khng ch mt bng v cao phc v cho vic o v bn t l ln , lp bo co nghin cu kh thi v thit k k thut thi cng. b) Cng tc trc a phc v thi cng xy lp cng trnh, bao gm: thnh lp li khng ch mt bng v cao phc v b tr chi tit v thi cng xy lp cng trnh. Kim tra kch thc hnh hc v cn chnh cc kt cu cng trnh. o v hon cng cng trnh. c) Cng tc trc a phc v quan trc bin dng cng trnh, bao gm: thnh lp li khng chcs,limcchunvmckimtranhmxcnhy,chnhxcccgitr chuyn dch, phc v cho vic nh gi n nh v bo tr cng trnh.Ba cng on trn c lin quan mt thit vi nhau v cn phi c thc hin theo mt trnh t quy nh. 4.3. Vic xc nh ni dung v quy m cng tc kho st o c a hnh, yu cu chnh xc thnh lp li khng ch thi cng v ni dung quan trc chuyn dch cng trnh l nhim v ca t chc thit k. - Vic tin hnh kho st o c - a hnh, thnh lp li khng ch phc v thi cng v vic t chc quan trc chuyn dch cng trnh l nhim v ca ch u t. - Cng tc o c b tr cng trnh kim tra cht lng thi cng xy lp cng trnh v o v hon cng l nhim v ca n v xy lp. 4.4. Ta v cao dng o c kho st trc a - a hnh, thit k, thi cng xy lp cng trnh phi nm trong cng mt h thng nht. Nu s dng h to gi nh th gc to phicchnsaochotocattcccimtrnmtbngxydngucdu dng,nusdngtoqucgiathphisdnghtaVN2000vkinhtuyntrc c chn sao cho bin dng chiu di ca cc cnh khng vt qu 1/50000, nu vt qu th phi tnh chuyn. Mt chiu c chn trong o c xy dng cng trnh l mt c cao trung bnh ca khu vc xy dng cng trnh. Khi hiu s cao mt t v mt chiu < 32m th c th b qua s hiu chnh Sh, nu ln hn th phi tnh s hiu chnh do cao.4.5. Tiu chun nh gi chnh xc ca cc i lng o trong xy dng l sai s trung phng. Sai s gii hn c ly bng 2 ln sai s trung phng. 4.6. phc v xy dng cc cng trnh ln, phc tp, v cc nh cao tng n v thi cng phi lp phng n k thut bao gm cc ni dung chnh nh sau: - Gii thiu chung v cng trnh, yu cu chnh xc ca cng tc trc a phc v thi cng xy dng cng trnh, cc ti liu trc a a hnh c trong khu vc. - Thit k li khng ch mt bng v cao (a ra mt s phng n v chn phng n ti u). - T chc thc hin o c. - Phng n x l s liu o c. - Phng n x l cc vn phc tp nh cn chnh phng, thng ng ca cc thit b, o kim tra cc khu vc quan trng vv... - S b tr v cu to cc loi du mc. 4.7.Trckhitinhnhcccngtctrcatrnmtbngxydngcnnghincutng bnh cng trnh, kim tra cc bn v chi tit s s dng cho vic b tr cc cng trnh nh: khong cch gia cc trc, khong cch tng th, to v cao ca cc im v c s ph duyt ca b phn gim st k thut ca ch u t. 4.8. i vi cc cng trnh ln c dy chuyn cng ngh phc tp v cng trnh cao tng cn phisdngccmymcthitbhinicchnhxccaonhmytoncint, my thu chun t cn bng c b o cc nh v mia invar, my chiu ng,.... thnh lp li khng ch c th s dng cng ngh GPS kt hp vi my ton c in t. Tt c cc thitbsdnguphickimtra,kimnghimvhiuchnhtheongccyucu trong tiu chun hoc quy phm chuyn ngnh trc khi a vo s dng.5. Kho st trc a a hnh phc v thit k cng trnh 5.1. c im v yu cu chung v bn t l ln. 5.1.1. Trn khu vc xy dng hoc quy hoch xy dng thng o v bn t l t 1: 200; 1: 500 n 1: 5000. 5.1.2. Da vo ngha v mc ch s dng bn t l ln c th phn chia thnh hai loi: - Bn a hnh t l ln c bn: Thnh lp theo cc quy nh chung ca c quan qun l nh nc gii quyt nhng nhim v a hnh c bn. Ni dung th hin theo quy nh ca quy phm hin hnh. - Bn a hnh chuyn ngnh: Ch yu l loi bn a hnh cng trnh. Loi bn ny c thnh lp di dng bn v mt ct c chi tit cao, dng lm ti liu c s v a hnh, a vt phc v cho kho st, thit k xy dng v s dng cng trnh. 5.1.3. Cc phng php ch yu c s dng thnh lp bn a hnh: - o v lp th v o v tng hp bng nh.- o v trc tip ngoi thc a bng phng php ton c, ton c in t hoc kinh v kt hp o cao b mt.- Bn a hnh c th v trn giy hoc th hin di dng bn s. Ni dung ca bn ny c lu gi di dng tp d liu v dng a hnh, a vt, to cao. 5.1.4. Ni dung ca bn a hnh t l ln cn th hin cc yu t sau: ng ng mc v cao ca tt c cc im c trng, (yu t a hnh); Nh ca v cc cng trnh xy dng, giao thng, h thng thu li, ng ng, ng dy cao th,inthoi,hao,sngngi...vcchintngachtquanstcnhcchin tng t gy, st l, cct v.v... Mc chi tit ca bn tu thuc vo mc khi qut ho theo tng t l. 5.1.5. chnh xc, chi tit v y ca bn a hnh t l ln c quy nh nh sau: - chnh xc ca bn a hnh c c trng bi sai s trung phng tng hp ca v tr mt bng v cao ca im a vt v a hnh v c quy nh l:mp = 0.3 mm i vi khu vc xy dng; mp = 0.4 mm i vi khu vc t xy dng; mH =1314 h Trong :h- khong cao u ca ng ng mc. i vi cng tc thit k, sai s v tr im tng h gia cc a vt quan trng khng c vt qu 0.2 mm x M (M l mu s t l bn ). chi tit ca bn a hnh c c trng bi mc ng dng ca cc yu t biu din trn bn so vi hin trng ca chng trn mt t.Bn t l cng ln, mc chi tit i hi cng cao. Sai s do khi qut a vt r nt i vi bn t l ln khng c vt qu 0.5 mm x M y ca bn c c trng bi mc dy c ca cc i tng cn o v c th biudinctrnbn,ncbiuthbngkchthcnhnhtcaitngv khong cch nh nht gia cc i tng thc a cn c biu din trn bn . 5.1.6. Vic la chn t l bn o v cho khu vc xy dng c quy nh nh sau: T l bn a hnh cng trnh c xc nh tu thuc vo cc yu t nh: - Nhim v thit k phi gii quyt trn bn - Giai on thit k - Mc phc tp ca a vt, a hnh - Mt ca cc ng ng, dy dn... Trongctnhnyucuvchnhxc,chititvycabn,cc chng php thit k v b tr cng trnh. -Giaionlplunchngkinhtkthutvthitksbcncbntl1:10000, hoc 1: 5000. - Giai on thit k quy hoch chi tit, thit k k thut, cn s dng cc loi bn sau: a) Bn t l 1: 5000, h = 0.5m 1.0m c dng thnh lp bn c s, tng bnh khu vc thnh ph, cng nghip, thit k n khu vc xy dng; b)Bntl1:2000,h=0.5m1.0mcdngthitkkthutcngtrnhcng nghip, dn dng, thu li, h thng ng dn, bn v thi cng ti tiu; - Giai on thit k k thut thi cng cn cc loi bn sau: a) Bn t l 1: 1000, h = 0.5m c dng thit k thi cng cng trnh khu vc cha xy dng, tng bnh khu vc xy dng thnh ph, thit k chi tit cng trnh ngm, thit k quy hoch, san lp mt bng; b) Bn t l 1: 500, h = 0.5m c dng thit k thi cng cng trnh thnh ph, khu cng nghip, o v hon cng cc cng trnh; c) Bn t l 1: 200, h = 0.2m 0.5m c dng thit k thi cng cng trnh c din tch nh nhng i hi chnh xc cao, o v hon cng cng trnh. 5.1.7. Khong cao u ca bn a hnh c xc nh da vo cc yu t sau: - Yu cu thit k v c im cng trnh; - chnh xc cn thit v cao v dc ca cng trnh; - Mc phc tp v dc ca a hnh; - Trong trng hp thng thng, khong cao u c chn nh sau: h = 0.2 m; 0.5 m cho t l 1: 200; 1: 500, vng ng bng; h = 0.5 m cho t l 1: 500; 1: 1000 vng ni; h = 0.5 m 1.0m cho t l 1: 500; 1: 1000 vng ng bng; 1: 2000; 1:5000 vng ni; h = 2.0 m cho t l 1: 2000; 1: 5000 vng ni.5.1.8. Ngoi vic th hin ni dung bn trn giy m phng hin trng b mt t theo cc phng php truyn thng nh ni trn, cc ni dung ca bn cn c th hin didngtpdliutrongccthngtinvmttnhta,caocaccim khngch,imchititahnh,avtcbiudindidngsvthuttonsl chng gii quyt cc yu cu c th. Loi bn ny c gi l bn s.5.1.9. thnh lp bn s cn c 2 phn ch yu: - Phn cng gm cc my ton c in t, my tnh in t v my v bn . - Phn mm chuyn dng thnh lp bn c ci t vo my tnh in t. 5.1.10. Cc s liu ban u thnh lp bn s c th c o c trc tip trn mt t, thu thp d liu bng phng php o nh hoc o trn bn . - Phng php o c trc tip trn mt t thu thp cc d liu v to , cao cc im chi tit bng my ton c in t t ghi chp s liu sau trt vo my tnh bin v bn bng cc phn mm chuyn dng. y l phng php c hiu qu kinh t v t c chnh xc cao.- Phng php o nh thu thp cc d liu ban u l phng php c hiu qu kinh t cao nht. Sau khi chnh l cp nh, tin hnh o cc im c trng ca a hnh, a vt, t ng xc nh ta , cao v m ho c trng ca cc im . Trong my vi tnh cc s liu c trng s c x l v a v h ta thng nht theo yu cu. chnh xc ca bn sgnnhphthuchontonvochnhxccasliubanu.Vvykhisdng phng php ny th chnh xc ca bn s ph thuc vo chnh xc o nh v t l nh. - Phng php o trn bn thng c s dng trong giai on lp lun chng kinh t k thut hoc thit k s b cng trnh c yu cu khng cao v chnh xc thnh lp bn . Do vy c th thnh lp bn s da vo s liu o trn bn a hnh t l ln nht c. Cch lm nh vy gi l s ho bn . 5.1.11. H thng phn mm chuyn dng thnh lp bn s bao gm: - Phn mm x l s liu li khng ch khu vc o v: Phn mm ny dng s l s liu o ngoi nghip, bao gm gii m, hiu chnh tr o, bnh sai trm my, t ng xp xp im v thnh lp cu trc s liu mng li, tnh s hiu chnh chiu hnh cho cc tr o, tnh ta gn ng cho cc im, tnh ton bnh sai v.v... - Phn mm bin tp hnh Cc s liu sau khi np vo my tnh th cn c vo cc loi m ca n c th t ng hnh thnh bn . Nhng do tnh cht phc tp ca bn a hnh, bn mi c hnh thnh khngthtrnhkhisaist.Docnphidnghnhthcgiaodin ngi-my,tin hnhgiacng,bintp.Phnmmbintphnhbaogm:hnhthnhbn,bintp, chuyn sang my v bn , chuyn sang my in.- Phn mm bin v cc k hiu v ghi ch trn bn a hnh: Phn mm ny bo m ch hnh v v cc k hiu, ng nt v cc kiu s, kiu ch. -Phnmmvccngngmc:Cncvoccimahnhtngnisuy,v ng ng mc v t ng ghi ch cao. - Phn mm s ho bn a hnh: Phn mm ny bo m vic chuyn bn a hnh t l ln hin c qua my s ho thnh bn s, bao gm c ta im cc yu t ca bn , chuyn i v lu ta , biu th hnh, to s thng nht gia s liu o thc a v s liu s ho bn c thnh lp bn s.5.2. Li khng ch o v bn t l ln 5.2.1. C s trc a o v bn t l ln l li trc a nh nc cc cp hng v li khng ch o v. Trn khu vc thnh ph v cng nghip li trc a c thit k phi m bo cc ch tiu sau: - chnh xc ca mng li khng ch cp trn phi m bo cho vic tng dy cho cp di nhm tho mn yu cu o v bn t l ln nht v cc yu cu ca cng tc b tr cng trnh. - Mt im khng ch phi tho mn cc yu cu ca t l cn o v. - i vi khu vc nh nn s dng h ta c lp (gi nh);5.2.2.Scphngcamnglituthucvodintchkhuvcovvcquynh theo bng 1, hoc m bo chnh xc tng ng. 5.2.3. Mt im khng ch gm cc im tam gic hng IV, ngchuyn cp 1, cp 2 o v bn ahnh t l 1/1000 1/2000 t nht l 4 im/km2 trung bnh t 8 im 12 im/1 km2; o v bn t l 1/500 mt im khng ch c th ln ti 15 im 18 im/1 km2 tu theo mc xy dng ca khu vc. 5.2.4. C s cao c xy dng di dng cao hng II, III, IV. Li hng II c thnh lp khu vc rng c chu vi ln hn 40 km, chiu di tuyn gia cc im nt khng ln hn 10 km. Li c tng dy bng cc tuyn cao hng III. Chiu di tuyn hng III c b trgiaccimhngIIkhngcvtqu15km;chiudigiaccimntkhng vt qu 5 km. Li hng III c tng dy bng cc tuyn cao hng IV. Chiu di tuyn b tr gia cc im hng II v III khng c qu 5 km. Chiu di tuyn gia cc im nt khng c qu 23 km. Cc im hng IV cch nhau 400m 500 m khu vc xy dng v 1 km khu vc cha xy dng. Bng 1. Din tch khu vc o v v cc cp hng ca mng li khng ch Khng ch c s Khng ch o v Mt bng Din tch o v (km2)Li nh nc Tng dy caoMt bng cao > 200 50 200 10 50 5 10 2.5 5 1 2.5 100 hac thnh lp bng phng php o cao hnh hc vi chnh xc tng i vi thu chun hng IIInhnc.iviccmtbngxydngcdintch