Hgi ngh, / nua hgc ky'''' niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam Hd Ngi J0/20JO DANH GIA RUI RO D Q N G DAT CHO CAC THANH PHO LON 6 VIET NAM SEISMIC RISK ASSESSMENT FOR MEGACITIES IN VIETNAM Ngu[.]
Hgi ngh, /.nua hgc ky' niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi J0/20JO DANH GIA RUI RO DQNG DAT CHO CAC THANH PHO LON VIET NAM SEISMIC RISK ASSESSMENT FOR MEGACITIES IN VIETNAM Nguyen Hong Phuong Vien Vat ly Dja ciu '; Moing Qude Viet, Cau Giay, Ha Ndi Email: phuong.dongdat(a)gmail.com Tdm tat: Mdi hiim hog ddng ddt thuang xudt hiin a nhirng khu vuc cd hogt dgng dja chdn tich cue vd tra nin ddc biit nguy hgi niu khu vuc dd ddng thai ciing la mdt khu vuc phdt triin cua cdng ddng Viec hogch dinh vd ddu tu cho cdc chiin luge gidm nhe thiit hgi dgng ddt gdy dang tra thdnh mot vdn di thai su rdt cdp bdch tgi nhiiu quoc gia trin thi giai, cd Viet nam Quan trgng hom, cdc chiin luge ndy cdn phdi dugc hogch djnh vd thue hiin ddng ddt cdn chua xdy ra, niu khdng mudn phdi trd gid cho nhirng chi phi Idm hom rdt nhiiu ldn cho cdc hogt dgng ung cim qud trinh xdy dgng ddt hay cdc hogt dgng tdi thiit vd phuc hdi sau ddng ddt Bdi viet ndy trinh bdy mdt sd kit qud sir dung cdng nghi GIS di ddnh gid rui ro ddng ddt dd thj cho ba thdnh phd lan a Viet Nam la Hd Ngi, thdnh phd Hd Chi Minh vd Nha Trang Mac dii mdi chi dugc thir nghiim nhirng phgm vi hgn chi, cdc kit qud nhdn dugc cung da dung lin mot birc tranh hiin thue vi mdi hiim hga dgng ddt vd nhirng thiit hgi md cdng ddng thj se phdi gdnh chju niu cd dgng ddt xdy Cdc kit qud uac lugng thiit hgi se la ca sa di di xudt cdc gidi phdp vd cdc quyet dinh diing dan nhdm: Cd ke hogch phdng trdnh, ngdn ngira vd gidm thieu nhung thiit hgi cho cdng ddng niu cd dgng ddt xdy ra; Du dodn truac bdn chdt vd quy md cua cdc hogt dgng img ciru tgi hiin truang xdy ddng ddt; Cd ki hogch cu thi vi viec khdi phuc vd xdy dung lgi sau ddng ddt xdy Abstract: Earthquake threats usually appear in high seismicity areas and become particularly dangerous if those areas at the same time are urban ones Planning and investment for strategies on reduce and mitigation of losses and damages due to earthquake and tsunami now become an urgent issue for many countries in the World Moreover, these strategies have to be made and implemented while earthquake or tsunami did not happen in order to avoid much more expenses for the during disaster rescue activities, or for the after disaster restore and recovery activities 203 Tiiu ban: Cdc Khoa hgc vi Trdi ddt ISBN: 978-604-913-016-8 This paper presents some preliminary results of using GIS to assess seismic risk and to estimate losses for urban areas of three biggest cities in Vietnam, namely Hanoi, Ho Chi Minh City and Nha Trang Although the methodology have been applied to a limited framework, the obtained results show a realistic picture of damage and loss that may result from future earthquakes at urban scale The estimates of damage and human impacts due to earthquakes can help the decision-makers at local, regional and national levels in: Mitigating the possible consequences of earthquakes; Anticipating the possible nature and scope of the emergency response needed lo cope with an earthquake/tsunami-related disaster, and Developing plans for recovery and reconstruction following such a disaster I MO D A U Viet nam duge biet den nhu mdt dit nude ed mdi hiem hoa ddng dit cao Nhiing trin ddng dit manh nhit vdi magnitude dat tdi 6,7-6,8 Rich ter vi tuong duong di dugc ghi nhin ljeh sir (1 trin vao the ky 14) vi bing miy (2 trin vio the ky 20) tren phin tiy bic lanh thd, d ngoii khoi, tren viing them lue dja ddng nam dit nude, ddng dit ghi nhin dugc eiing di dat tdi magnitude 6,1 (ddng dit Hdn Tro nim 1923) Phin phia nam cua dat nude eiing khdng nim ngoii viing inh hudng eiia ddng dit Ngiy thing 11 nim 2005, mot trin ddng dat cd ldn 5,1 Rich te di xiy d viing bien gin Viing Tiu Ciing ngiy, mdt trin ddng dat ldn hon cd ldn 5,5 Rich te lai xiy tai ngoii khoi Nam Trung bd Tir dd den nay, nhirng trin ddng dit cd ldn trung binh vin xiy thudng xuyen tren viing them luc dja ddng nam nude ta, gay chin ddng inh hudng tdi cic phd ldn dgc theo dii ven bien mien Nam vi boat ddng khai thie diu tai khu vuc niy Theo cae ehuyen gia dja chan, mdt sd dd thj ldn vi eic khu cdng nghiep eiia Viet nam hien dang nam tren nhirng khu vue ed nhay cim cao trude nhirng rung ddng dja chin Chang ban, thu dd Ha Ndi hien dang nim tren vimg duge du bio phii chju dung chin ddng cip Cic khu vuc din eu vi cic cdng trinh thuy dien ldn eiia dit nude tai Tiy bic nhu Dien bien, Tuan Giio, Lai Chiu, Son la, v.v cd the phii chju dung nhiing chin ddng cip 8-9 tuong lai Di Ning, Dung Quit vi mdt so khu vuc dd thj eiia miln Trung nude ta eiing nim viing cd the chju inh hudng chin ddng ddng dit tdi cip Ddi vdi thinh phi H I Chi Minh, nii ro dja chan ldn nhit cd ning phit sinh tir su lan truyen chdn dgng dia chdn til eic tran ddng dit manh d pham vi khu vuc, vi sir khuich dgi rung ddng nin cac hieu irng nen dja phuong gay dudi tii trgng ciia ddng dit Viee hoach djnh vi diu tu eho cie chiln luge giim nhe thiet hai ddng dit gay dang trd thinh mdt van de thdi sir rat cip bich tai nhilu qude gia tren thi gidi, dd ed Viet nam Quan trgng hon, cic chien luge niy ein phii duge hoach dinh vi thue hien ddng dat edn chua xiy ra, neu khdng mudn phii tri gii cho nhiing ehi phi ldn hon rit nhilu lin eho eic boat ddrig iing cuu qua trinh xiy ddng dat hay eic boat ddng tii thilt vi phuc hdi sau ddng dit Mdt nhiing ddng gdp tich cue va khdng nhd eua cae nha dja chin Viet Nam vao chien luge eua qude gia ve phdng ehIng ddng dit vi giim nhe thiet hai ddng dit ehinh li cie edng trinh nghien cuu danh gii nii ro ddng dit dd thj eho cie phd ldn d Viet Nam, duge bit dau trien khai thue hien d Viet Nam tir nim 2000 din Bii viit niy gidi thieu mdt sd ket qui dinh gii nii ro ddng dit va udc lugng thiet hai eho ba thinh ldn d Viet Nam li Hi Ndi, thinh phd Ho Chi Minh va Nha Trang 204 Hgi nghi Khoa hgc hi' niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi JO 20JO II XAY Dl/NG HE THONG CONG CU DANH GIA RUI RO D Q N G DAT DO THI Phuo-ng phap luan Phuong phip luin dinh gii nii ro ddng dit dd thj cho eic thinh phd ldn d Viet Nam tip trung vio hai ddi tugng chju thiet hai chinh li ngudi vi nha eiia Phuong phip luin di duge ip dun^ cho mdt sd thinh phi ldn cua Viet Nam nhu Hi Ndi, thinh phd Hd Chi Minh vi phd Nha Trang f3, 4, 5, 6] Quy trinh gdm hai budc chinh li 1) dinh gii nguy hiem ddn^ dit va 2) dinh gii nii ro ddng dat Theo quy trinh niy, giiia cic thinh phin cua toin bd eiu tnic ed mdi quan he nhin qui vdi nhau, tire la eic ket qui eua mdi giai doan cd the duge xem nhu la sd lieu diu vio true tiep eho giai doan tiep theo Mo hinh nguon phat sinh dong dat Do phin ldn cie tran ddng dit ghi nhan dugc d Viet nam deu li nhirng ddn^ dit ed ngudn gdc kien tao, ngudn phit sinh ddng dit (chin tieu) dugc gii thiet la mdt ngudn tuyen md phdng mdt doan dirt giy boat ddng Md hinh ngudn tuyen eho Viet nam duge xiy dung tren co sd sd lieu ve eac he thdng dirt giy sinh chin da duge xic dinh tren linh thd vi viing them luc dia Viet nam va di duge edng bd rdng rai nhieu edng trinh nghien cim tir trudc den [1, 2, 8, 9] Viee xie djnh eic diit giy sinh chin ehu yeu dua tren eo sd quy luat ve tinh dia ddi eiia cie chin tim ddng dat, tue la sir phin bd cua cic chin tim ddng dit dgc theo cic ddi dirt giy phi buy Ngoii ra, cie yeu td dia chat, dia vat ly va vien thim khie eiin^ dugc tham khio nhu eac tieu chuin bd trg eho viec lira chgn cic dirt giy ed ning sinh chin Hinh Cdc hi thdng dirt gdy cd khd ndng sinh chdn trin lanh thd vd thim luc dia Viit nam De xiy dung md hinh ngudn tuyen eho Viet nam, cdng thue cua Wells vi Copersmith dugc sir dung flOf Tdng cdng 46 he dirt giy ed ning sinh chin tren lanh thd va them lue dja Viet nam dugc thu thap vi phin thinh hai nhdm ed cip dirt giy khie nhau, dd nhdm cap bao gdm cic dut giy ndi ming thach quyen, ddng vai trd phin chia cae vi ming, cdn nhdm cip bao gdm eic dut giy ddng vai trd phin chia cie dja khdi, cic ddi cau tnic nam ldp vd Trii Dat Hinh minh hoa bin dd eic he thdng dirt giy ed ning sinh chin dugc sir dung de xiy dung md hinh ngudn tuyen cho Viet nam [7] Cac dong dit kich ban Md hinh ngudn tuyen dugc ip dung de xay dung cic dgng dat kjch bin phuc vu cho viec tinh toin thiet hai ve nhi cira va ngudi tai cie khu vue nghien cim Dgng dit kjch bin li ddng dit dugc du bio se xay tai khu vue nghien cuu, vdi eic thdng sd ban diu duge xie dinh trudc Ndi each khie, ddng dit kjch bin li sir md phdng nhirng trin ddng dit di xiy qui khir, nhim du bio inh hudng eua nhirng trin dgng dit se xiy Urong lai Cic ddng dit kich ban duge xiy dung eho ba phi ldn Hi Ndi, thinh phd Hd Chi Minh va Nha 205 Tieu ban: Cdc Khoa hoc ve Trdi ddt ISBN: 978-604-913-016-8 Trang dua tren cie gii thiet sau: 1) Ddng dit duge phit sinh tren mdt nhirng dirt gay kiln tao cd ning sinh chin chay cit ngang qua hoac gin dja bin thinh phd Chan tim ddng dit kjch bin duge liy tai mdt diem nim tren dirt giy phit sinh nd va cd khoing cich gin nhit tdi dja phin thinh phd 2) Ngoii tga chin tam, eac tham sd khie cua ddng dit kjch bin dugc xic djnh theo eic tham sd hinh hgc va dja ddng lire ciia chin doan dirt gay phi buy phit sinh nd (chin tieu ddng dit kjch bin) theo eic nguyen tic ciia md hinh ngudn tuyen da md ta d tren He thong ho trg" quyet dinh Md hinh ngudn tuyen duge ip dung de xiy dung edng cu phin mem dinh gii nii ro ddng dat vi udc lugng thiet hai d pham vi dd thj Cdng cu niy cd ten ggi li AreRisk, dugc viet bing ngdn ngir Avenue tren co sd bien giao dien eiia phin mem ArcView GIS Cic md dun tinh toin cua AreRisk tuin thu quy trinh dinh gii nii ro ddng dit dd thj vi duge dinh sd nhu tren hinh Quy trinh dugc thue hien qua nhieu giai doan, dd kit qui thue hi^n rndi ^iai doan duge sir dung lim sd lieu diu vio cho giai doan tiep theo Quy trinh duge bit diu bing viee xie djnh khu vuc nghien cuu Tiep dd li viee xie djnh trin ddng dit "kjch bin", dugc du bio se xiy tai khu vue nghien cim, vdi cic thdng sd ban diu dugc cho trudc yi cd the dugc thay ddi bdi ngudi sir dung Tren eo sd eic sd lieu hien ed vi sir bilu biet ve tinh dja chin, dja chin kien tao, dja chit cdng trinh vi dieu kien nin, ning rung dgng nen duge dinh gii eho khu vue nghien cim Cic ket qui niy, dugc sir dung lim dii lieu dau vio de dinh gii ning phi buy nen Cudi eiing, eic thdng tin vl nhay cim eua eic yeu td chju nii ro nhu mat din sl, phin bd nha cua, co sd ting, cie he thing ky thuat, v.v duge dua vio ket hgp vdi eic ket qui dinh gii ning phi buy nin dl tinh toin va udc lugng tdn thit Ngoii ehiie ning li mdt edng eu manh viee dinh gii nguy hiem vi nii ro dgng dit bin^ edng nghe GIS, AreRisk cdn dugc thilt kl dl cd thi sir dung nhu mdt He thing hd trg quyet djnh edng tie phdng ngira, ung cuu vi giim nhe thiet hai ddng dit giy dii vdi edng ddng dd thj tai Viet Nam Xic djnh vimg nghien cuu Xic djnh ddng dit kjch bin Danh gii Khi ning rung ddng nen Danh gii Kha nang phi buy nin Udc lugng Tdn that Ra quyet djnh: - Phdng trinh, ngin ngira, giim thieu thiet hai; - Ung cuu khin cip; - Khdi phuc, tii thilt Sd lieu dieu tra dan sd, nhi cua va cac yeu td chiu nii ro khac Hinh Quy trinh ddnh gid nii ro ddng ddt dd thi bdng Hi thdng hd trg quyet dinh 206 Hgi nghi Khoa hgc k\' niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi JO 20JO IV MOT SO KET QUA DANH GIA RUI DO RO DONG DAT VA \fCiC LUONG THIET HAI CHO CAC THANH PHO LON CUA VIET NAM Phin mem AreRisk dugc ip dung de dinh gii nii ro ddng dit cho eic khu vue sau diy : 1) Cic quan Hoin Kilm, Ba Dinh vi Hai Bi Trung eua thinh phd Hi Ndi f3, 4f; 2) Cie quin vi eua thinh phi H I Chi Minh f5f; 3) Khu vuc trung tim gdm 11 phudng eua thinh phd Nha Trang f6J Ddi vdi mdi kjch bin ddng dat, AreRisk tu dgng tinh toin vi hien thj eic ket qui sau diy cho khu vue nghien cim: • Bin dd rung ddng nen bieu thj phin bd gia tdc cue dai nen ; • Cic bin ehuyen de bieu thj ning phi buy nen cie hien tugng trugt Id nen va hda ldng nen ddng dit giy ; • Tip bin dd thiet hai nha cira ddng dit d muc thiet hai khie (Nhe, Trung binh, Ning vi Hoin toin); • Tip bin dd thiet hai ve ngudi ddng dit d ba thdi diem khie ngiy (2 gid sing, 14 gid vi 17 gid) vi mire thuong vong khie Ngoii ket qui dudi dang bin dd, cic bio bieu thdng ke thiet hai nhi eua vi ngudi ddng dat ciing dugc tu ddng xiy dung eho mdi kich ban Tren hinh minh hga ket qua danh gii nii ro ddng dit cho quin Ba Dinh, thinh phd Ha Ndi theo ddng dit kjch bin dut gay Sdng Chiy (Mw = 6,6, h=15 km) Cac bin dd duge minh hga bao gdm : a) bin dd rung ddng nen ; b) bin dd thiet hai nha cua d mirc ning vi e, d) bin dd thiet hai ve ngudi d miie tai 02 gid va 14 gid Tren hinh minh hga ket qui dinh gii nii ro ddng dat eho 11 phudng tai trung tim thinh phd Nha Trang Cie bin dd duge minh hga bao gdm : a) ban dd thiet hai nhi cira d mirc trung binh va b) ban dd thiet hai ve ngudi d mue liie gid sang Tren hinh minh hga ket qui dinh gii nii ro ddng dit eho eac quan vi 3, thinh phd Hd Chi Minh theo ddng dit kjch bin dirt giy Thuin Hii-Minh Hii (Mw = 5,6, h=15 km) Cic bin dd duge minh hga bao gdm : a) ban dd thiet hai nhi ciia d miie nhe va b) ban dd thiet hai ve ngudi d miic tai 14 gid a 207 Tieu ban: Cdc Khoa hoc ve Trdi ddt ISBN: 978-604-913-016-8 C ^ Hinh Kit qud ddnh gid rui ro dgng ddt cho qudn Ba Dinh, Hd Ngi theo dgng ddt kjch bdn dirt gdy Sdng Chdy (Mn- = 6,6, h=I5 km) V RUJOng/XA y -PfTB) o-an) • i ••s-in%} 10 I5(%) 15-20(%) a8^20-25