CONG NGH$ VA THI^T Bl.
T R A CDjA HlEN OAI
TRONG 0 0 OAC CONG TRJNH GIAO
T H O N G , T H O YLOI DANG TUY^N
rs. Vu Thing
Khoa Xay dung Ciu dudng Trudng Dai hgc XSy dt/ng
Tdm tat: Cdng nghd va thiet bi trie dia hidn dai duge sir dung trong khao sSt dja hinh, eho dp ehinh xSe eao, tai lieu duge sif dung lai a cSe budc khao sat sau, dSe bidt tren md hinh sd dp eao cho khi nSng quan ly tuyin theo tga dp.
DSy la phuang phap quan ly tuyen rit hidu qua.
Summary: Modern Technology and geodetic equipment have been used in designing digital terrain model. The accuracy level of each point is suitable for each step of investigation. Typical eharacterlsties of the line are managed with points' co-ordinate in the digital topographic map. From these features, there must be a suitable process for the investigation of topography to server the eonstruetion of line projects.
1. DAC TRl/NG CUA CONG T A C KHAO S A T OIA HINH CONG TRINH GIAO THONG, THUY LOI DANG TUYEN
Cdng trinh giao thdng, thuy ldi thudng la nhifng dang edng trinh hinh tuyin, trai ddi theo dang dat. Trong qua trinh thiit k i , xdy dung eae ehi tieu ky thudt, chd't lupng, hidu qua kinh t i eda cac edng trinh dUpc xac djnh phy thupc nhiiu bdi y i u td dja hinh. Mdt cdng trinh ed dap dng dupc cac ydu c i u ky thudt, co hidu qua kinh te hay khdng, thi y i u td dja hinh ddng mpt vai tro rit quan trpng. Nhieu cdng trinh do sd lieu khao sat dia hinh khdng day dd, thiiu chinh xac hoac qua trinh thiit k i chua quan tam ddng mdc tdi ye'u td dia hinh dan tdi cdng trinh khdng dam bao cac yeu cau v i kinh t i , ky thuat; tham chi nhiiu edng trinh khdng t h i dua vdo khai thac sd dung, dan tdi vide d i u tu xay dung kem hieu qua.
Cdc tham sd ky thudt dae trUng v i tuyin edng trinh trong qua trinh khao sat thiit k i thudng xdc * n h difa theo binh dd, mat cat dpc va mat c i t ngang tuyin. Vide xac dinh vi tri dinh dudng cong bang, dUdng cong ddng; xae djnh cac tham sd dudng cong bj phy thupc nhieu vdo dja hinh dpe.tuyin.
Qua trinh khao sat, thiit k i lap lai nhiiu lan tren cdng mdt tuyin qua cdc giai doan, cac budc thiit ke, td lap phuong an kha thi, thiet k i ky thudt va cudi cung la lap ban ve thi cdng.
Khdi lupng dao dap cua cdng trinh thudng dupc tinh dua trdn mat c i t ngang. Mat dp mat cit ngang sddyng trong cae giai doan khac nhau td lOOm/cdt, 25m/cat, de'n 20m/eit vd mat cit ngang bd xung d cdc vj tri dac trung tren tuyin cda cdng trinh, nhu diem dau, diim giiira, diim cudi dudng cong, hay eae vj tri cd dja hinh thay ddi dot ngdt... Op chinh xdc tinh khdi lupng ddo dip phy thupc vdo dp chinh xae, mat dp khao sat do ve mat c i t va phu thudc vao ddc trung eda dia hinh.
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2. KHA N A N G CCIA THIET Bj VA CONG NGHE HIEN OAI TRONG KHAO SAT OIA HINH Theo edng nghd truyen thdng, cdng tac khao sat dja hinh tuyen thudng dupc thyc hien theo cac phuong phap do ve true tiep, sd dung cac may quang co. Do eae han ehe cda thiet bj, dieu kidn gid thdnh khao sat, dp chinh xac lap tai lieu (Sa hinh chi dat du dp chinh xac yeu c i u cda ti le tdi lidu khao sat can lap trong ttmg giai doan. Cac giai doan tie'p sau lai phai khao sat lai d mile dp chi tiet va chinh xac hon. Sd lieu khao sat d cac giai doan trudc thudng chi sd dung i5i/pc cac diim mdc khdng che, cdn npi dung do ve ehi tiet hau nhu khdng dupe sd dyng lai. Npi dung do ve chi tiet cu chi dung de tham khao vi han c h i ve dp chi'nh xae vd edng nghe tai sijr dung.
Hidn nay nhd tie'n bp cda khoa hpe ky thuat, ede thidt bj, edng nghd umg dyng trong khao sat dja hinh nhU todn dac dien td (TOOT), he thdng djnh vj todn cau GPS, ban dd ky thuat sd eo nhieu Uu diem hon.
Cac may TOOT ed kha nang xae dinh vj tri diem vdi dp chinh xdc ra't cao, thoa man yeu cau ldp t i t ca cac loai ban dd ti Id Idn. May TOOT khdng ngimg dupe ndng cap, hodn thien; TU thi hd may TOOT do vdi dang guong phan xa vuong gde tdi dang gUong 360°, td may TODT cin ngUdi do bit myc tieu tdi may tU dpng bit myc tidu. Td may do phai ghi sd lieu bang tay tdi may tif luu sd lidu, gidp tranh dupc ldi sai lam thudng xay ra trong qua trinh ghi chep sd lieu.
Hd thdng djnh vj toan cau GPS img dyng trong trie dja cho nhieu kha ndng mdi, vdi cae tinh nang ky thudt hon hin so vdi cae thiit bi cu. Xdy dung ludi khdng ehe trie dja bang cdng nghe GPS cd nhiiu Uu diem vUpt trdi ve dp ehinh xac, khoang each do, yeu c i u thdng hudng, dieu kien thdi tiit, thdi gian thue hidn...
Sd lidu do ve true tiep de lap tdi lieu khao sat dja hinh phyc vu thiit k i cdng trinh giao thong, thdy Ipi dang tuyen, ed the thue hidn bang nhieu phuong phap:
- Oo bing TOOT, cae sd lieu do dupc tu dpng luu trong may sau dd chuyen sang may tinh, sd lieu do dupe gid nguyen dang, tranh dupe sai sdt do ghi chep, nhdp sd lieu . Od la ldi sai sdt, rit khd khac phyc trong qua trinh khao sat bang thiit bj va cdng nghd eu. May TOOT dupe ndng cap nhiiu lin vdi cac tinh nang vupt trdi hdn. Td t h i he TODT sd dung gUOng vudng gde mdt chiiu, guong 360°de'n may cd c h i dp do khdng guong, td khoang each do gidi han vai trdm met tdi khoang each do vai nghin met Td may do ngudi do diiu khien tn/c tiip d i n mdy cd c h i dp tu bit mue tieu, tu do va tu dpng luu sd lieu. Vdi TOOT khi do ve dia hinh theo phuong phdp true tiip cho nhiiu kha nang mdi ve dp chinh xae, khoang each do, vdi may cd c h i dp khdng guong khie phyc dupe nhdng khd khdn khi tie'p can dja hinh ddc biet hiem trd.
- Bing cdng nghd GPS, vdi thiit bj do ve cam tay dpc lap hode k i t ndi vdi TOOT viec xac djnh vj tri diim dupc thyc hien tai hidn trudng va cd t h i cho dp chinh xdc cao, tranh thie'u sdt diim khi dja vat dupe ve, hiin thj true tiip. Vdi phuong phap do ddng, mdt cat dpc tuyen dupe do bing cdng nghe GPS nhanh chdng cho sd lieu tdng quat gidp eho vide ehpn phuong an tuyin dupc xac djnh nhanh chdng, ddc biet hieu qua khi chpn tuyin mdi, trong diiu kien dja hinh phdc tap.
- Oo ve dia hinh mat bang cd the dupc thifc hien td eae mo hinh anh lap the lap, xdy dung bdng anh ky thuat sd chyp tU mat dd't, anh hang khdng hoac anh vidn tham. Ode bidt ddi vdi cdng trinh dang tuyin vide khao sat dja hinh chi tiet, phyc vy thiet ke giai doan cudi, tai cdc mdi dde cd dd ddc ldn, dia hinh hiem trd, ngudi do khd cd the den dupc, cong nghe anh sd chup trirc tiip td mat d i t the hidn kha nang khao sat dja hinh ma eae phuong phap khde khong thuc hien duoc hode thifC hidn vdi dp chinh xac thap. Anh vd tinh toan cau tai tU "Google earth' k i t hpp
TAP CHf KHOA HOC C O N G N G H $ XAY DUNG SO 02 -12/2007 107
vdi do ve bd sung true tiip ngoai thue dja rit nhanh chdng eho ehung ta sd lieu khao sat dia hinh tuyen, ddc biet hidu qua vdi ndi dung dia vdt trdn tuyen c i n the hidn, phue vy nghidn edu khao sat nhanh. Vdi phan mim 3D, kit hpp do eao true tiip bang TOOT vdi c h i dp do khdng guong d i xde dinh dp cao edng trinh dpc tuyin, ed the xdy diJng md hinh lap the tuyin phd phyc vu qui hoaeh, ddc biet la qui hoaeh mdt ddng cae tuyin phd khu dd thj.
Trdn md hinh sd dja hinh, sd lieu khao sat cda eae diem chi tiit ddc trung cho dja hinh, (Jja vat tdcae giai doan trude dd dp chi'nh xdc sddung vao cdc giai doan sau. Viec xdy dung mo hinh sd (Jja hinh dua trdn sd lieu khao sat qua nhiiu giai doan cho tai lieu ed tinh lidn tyc, ke thda, khong phai do di do lai todn bd cae diem md ehl do bd sung cdc diem e i n thiet Mdt cit dpc tim tuyin vd cac mat cit ngang dupc xac djnh theo tuyin dupe chpn, da dupc thay ddi hidu chinh qua cac budc thiit k i , dua vao md hinh sd dja hinh xdy dung qua cae bude md khdng ein phai do ve Inlc tiep ngoai thuc dja nhu edng nghe cu. Do chinh xac lap mat cat ehi phy thudc mdc dp khdi qudt hda dja hinh. Mat dp diim chi tiet vd dd khai qudt hda t h i hidn qua ti Id cda md hinh sd dja hinh dupc lap. Trong qua trinh khao sat thiet k i , vide chpn tuyin ngodi thuc dja kit hpp vdi mo hinh sd dja hinh, dae biet trong giai doan lua chpn phUOng an vd chi'nh xae hda tuyen cho k i t qua tdi uu vd rat hieu qua. Dam bao dupe ydu cau ky thudt, tdn it cdng sdc, d i bd sung hidu chinh vd hidu qua kinh t i hon. Day la kha ndng hon h i n so vdi each thiit k i truyin thdng the hien tren giiy.
3. XAY DUNG QUI TRINH K H A O S A T , THIET KE PHU HOP
Vide thuc hidn khao sat, thiit k i cdng trinh giao thdng. thdy Ipi dang tuyin bing thiet bi vd edng nghe hidn dai de dam bao cac ydu cau ky thudt, rut ngin thdi gian va hieu qua kinh t i , Chung ta ein ed mpt qui trinh phu hpp, cd nhdng diem khae vdi qui trinh hien dang dugc dp dung. Cac budc c i n thue hidn trong qui trinh mdi, khi img dung thiit bj vd cdng nghd hidn dai Id:
Tu cac tdi lieu khao sat dja hinh da cd, kit hpp vdi cac ydu cau v i kinh t i ky thuat bUde diu xae djnh tuyin cda cdng trinh.
- Xdy dyng ludi khdng che mdt bing va dd cao, dd dp chi'nh xdc vd mat dp diim cho tat ea cac budc tiip theo. Ludi khdng c h i mdt bing thudng ed hai hoac ba c i p . LUdi mat bing eip trdn Id ludi hang III hoac hang IV, do theo edng nghd GPS vd dupe k i t ndi vdi mang ludi qud'c gia. Ludi mdt bing hang dudi thudng Id dudng chuyin cap 2. Ludi dp eao hang trdn Id hang HI hode hang IV, do theo phuong phap do cao hinh hpc td gida. Ludi dp eao hang dudi Id dudng ehuyen dp cao ky thudt, ed t h i do theo phuong phdp do cao hinh hpc vdi may thdy binh, do cao lupng giac vdi may IDDl, do cao GPS. Ode bidt luu y he dp eao dung trong xdy dung cdng trinh. Can cd su kiem tra ddnh gia phuong phap, kit qua chenh cao do dupe, ddc biet khi sd dyng chdnh cao trie dja do bing GPS.
- Khao sdt (Jia hinh, lap binh dd tuyin, mdt c i t dpc va m i t cat ngang qua cdc budc theo ydu c i u cda edng tac thiit k i tren md hinh sd dia hinh dupe do bd sung qua cac bUde khao sat dja hinh. Khi do bdng TOOT dp chinh xae cac diem chi tiit thoa man ydu eiu cda cac loai ti Id ban dd, Chi khdc nhau d mat dp diem va mdc dp khai quat hda, vi vdy cae diim ehi tiit do d giai doan trudc van cd the dung vao giai doan sau. Giai doan khao sat tiip theo chi c i n do bd sung dd mat dd diem can thiit dap img yeu cau cua ti Id ban dd c i n lap.
4. QUAN LY CONG T A C KHAO SAT, THIET KE, THI CONG CONG TRINH DANG TUYEN THEO TOA OO
Bing thiit bj va edng nghd hidn dai, ngdy nay ban dd, mat cit thudng dupc ldp td md hinh sd dia hinh. Trdn md hinh sd dia hinh cd dupe, vide xdc djnh tuyin cdng trinh, chuin hda
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tuyen qua ttmg budc. Tuyen cdng trinh dupc xac (^nh (Ji qua cae diem dja danh can tdi, cac diem (fia vat can trdnh, cap nhdt cac thong sd thiet ke nhu ban kinh cong, dp dai dudng cong, dp ddc cdng trinh, xac (Jjnh khdi lupng dao dap... de so sanh cac phuong an, xdc djnh phuong an tuyin dugc chpn. Tuyen thiet ke dupc chpn ngoai thuc d\a kit hop vdi md hinh so dja hinh ed nhieu li/a chpn, cd diiu kien so sanh, danh gia giua eae phuong an tuyen cho kit qua chpn phuong an tuyin tdt hon.
Vide xae djnh tuyen theo phuong phap truyen thd'ng, dugc xac djnh so bp trong phdng dua trdn cac tdi lieu khao sat dja hinh da cd, sau dd tuyen dupe chpn vd ed djnh ngoai thue dja nhp cac cpc djnh tuyen. Vide khao sat (Jia hinh tiip theo dupe thi/c hien theo tuyen da duoc xac djnh. Mpi diiu chinh cac tham sd v i tuyin dupc thuc hien qua cac budc thiet ke dupc cap nhat trdn tuyin thdng qua vide khao sat, thiet ke bd sung vd chdn lai cdc cpc dinh tuyin. Ly trinh cda tuyen da dupe xac djnh sau khi dinh tuyen ngoai thuc dja. Mpi thay ddi, hidu chinh tuyen d cae budc sau deu lam cho ly trinh thue t i eda tuyin thay ddi nhung chung khdng duoc cap nhat bd sung.
Qua trinh khao sat, thiit ke, thi cdng edng trinh dang tuyen thi vide ed dinh tuyin, quan ly cac cpc djnh tuyin, ban giao gida cac bdn lidn quan Id mdt vide Idm phdc tap, mat nhieu thdi gian, cdng sdc, thdm chi gdy nhiiu khd khdn trong qua trinh thUc hien thiet ke xay dung edng trinh.
Trdn md hinh sd dja hinh, vide nghien cdu xac dinh tuyin tdi uu cd nhiiu phuong an, gidp chpn dupc phuong an thda man cac yeu eiu dat ra. Cd dinh tuyin dupc thuc hien trdn mo hinh sd dp cao tuong ddi don gian. Vide thiit k i quan ly tuyin hodn toan cd the dupe thUc hien nhd tpa dd diim trdn md hinh sd dja hinh. Ody Id edng viec don gian, mat it thdi gian, dd thue hien vd rit hidu qua, dam bao eae yeu cau kinh t i va ky thudt. Mpi hieu ehinh thay ddi cdc tham sd v i tuyin diu dupc cap nhdt Ly trinh eda tuyen Id ly trinh thifc t i dupe xae djnh d budc cudi cung cua cdng tac thiit k i . Id ly trinh thue eda cdng trinh se dupc xdy duny.
Trdn md hinh sd dja hinh, viec thiit ke quan ly tuyen hodn toan difa vao tpa dp diim mdt bing XY vd dd cao H. Khi triin khai thi cong rat thuan Ipi, cac yeu td v i tuyen dupc trien khai xdc djnh ngodi thuc dia thudng sd dyng TOOT va dua theo cac diem mdc khd'ng c h i . Trong vide quan ly tuyin, bdn giao tuyen gida cac bdn lien quan dupc thifc hidn theo tpa dp trong hd so thiit k i , edng tac hidn trudng chi Id kiim tra.
Hidn nay vide quan ly edng tde khao sat, thiit ke, thi eong trinh tuyin theo tpa dp tren mo hinh sd dja hinh da va dang dUpc dp dyng. NhUng qui trinh, qui phain hien hanh chua dieu chinh kip thdi. Tren thue t i , khi xay dung cdng trinh edn nhiiu bat cap. Nhiiu trUdng hpp vi nhung ly do rat khac nhau, ddi khi la phi ky thudt, ngudi ta dp dat viec khao sat, thiet k i thi edng theo cpc ly trinh dupc xde djnh ngoai thuc dja, bang cdc cpc tren mat cat dpc, cdc cpc trdn mat cit ngang cd djnh ngodi thUc dja theo phuong phdp truyen thdng md khdng can biet tdi kha ndng khi dng dyng cdng nghd vd thiit bj hidn dai, khdng can biet tdi cae han che eda phuong phdp tmyin thd'ng, dan de'n vide cham tre ve tiin dp thi cdng, lang phi kha ndng eda thiet bj, de thuc hien mpt ndi dung tuong duong, gay mit thdi gian vd khdng hieu qua kinh t i .
Vide quan ly cdng tdc khao sat, thiit k i , thi edng edng trinh dang tuyin theo tpa dp tren md hinh sd dd eao vd dupc djnh vj ngoai thuc dja khi can thiit la phuong phap phdt huy dugc kha nang cda thiit bj vd cdng nghe hidn dai dang dupc dng dyng trong khao sat thidt k i cong trinh vd c i n dupc eu t h i hda trong cdc qui trinh, qui pham.
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So vdi trinh tif cim cpc ngodi thifc dja, quan ly tuyen theo tpa dp nhu trdn gidp rut ngin thdi gian vd edng sdc r i t nhiiu md van dam bao eae yeu eiu ky thuat v i thiit k i xay dung, sd dung va quan ly cdng trinh dang tuyin trong giao thdng vd thuy Ipi.
NhCmg npi dung d i cap d tren, chdng tdi da nghien cdu vd img dyng cy t h i rat hidu qua trdn nhiiu edng trinh ve giao thdng thdy Ipi dang tuyin.
Tai lieu tham khao
1. VO Thang - lu dpng hda khao sat trie dia trong xdy dung. O i tai NCKH cap Bd, md sd B2002-34-29.
2. Qui pham do ve ban dd dja hinh ti Id Idn - 96 TCN 43-90.
3. Tieu chuan Viet Nam - Khao sat cho xdy dung - TCVN 4419 ; 1987.
4. Tidu chuan trie dia xdy dung TCXDVN 309:2004.
5. Tidu ehuan 14 TCN 115-2000 - Khao sat dja hinh trong cdc giai doan lap du an vd thiit k i cdng trinh thdy Ipi.
6. Qui trinh khao sat dUdng dtd 22 TCN 263-2000, ngdnh GTVT.
7. Vu ThSng - Trie dia qui hoach dudng vd dd thi, Nxb Xdy dung. Ha Ndi, 2000.
8. VO ThSng - Trie dja xdy dung, Nxb Khoa hpc Ky thudt Hd Npi, 2004.
9. Vti ThSng - Mdt vdi so sanh qui pham vdi thuc t i khao sat dia hinh bang thiit bi vd cdng nghd hidn dai. Tuyen tap edng trinh khoa hpe - Oai hpc Xay dung, 1-2000.
10. VO ThSng - Op chinh xdc cda ban dd dja hinh ti Id ldn phyc vy khao sat, thiit k i vd xdy dung cdng trinh. Tuyin tap edng trinh khoa hpc, Oai hpc Xdy dung, 1-1999.
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