BO KHOA H(PC VA CONG NGHE CHirONG TRINH KHCN CAP NHA NlTOfC KC 08/06-10 B6 TAI: "Nghiin cAu cas&khoa hgc vA dexudt cdc giii phdp khoa hgc cdng ngh$ bio dam sif on dfnh vd d^ bin cda di biin hi$n c6 trong truing hgp sdng, triiu cwemg trdn qua di" MS s6: KC08.1S/06-10 BAO CAO XAC ejNH TAN SUAT MI/C NU'dC DE B|£N HIEN CO e£ DANH GlA TAN SUAT VU-OT TAN SUAT THiei Ke vA xAc ojNH CAC T6 HOP SONG, TRieu vA NU'drc DANG CO THi XAY RA TRONG VUNG BI^N tUT&C TA Ca quan chu tri: Truang Dai hpc Thuy Igrj Chu nhi#m <Sk tei: GS.TS. Ngo Tri Vieng Ha noi, 2010 BO KHOA HOC VA CONG NGHE CHirONG TRINH KHCN cAP NHA NU'dC KC 08/06-10 D6 TAI: "Nghien cieu ca s& khoa hgc va de xuat cdc gidi phdp klioa hpc cong nghe bdo ddm sir on dinh vd dp ben cua de bien hien cd trong trie&ng hap sdng, trieu cirdng trdn qua de" Mas6:KC08.1S/06-10 BAO CAO XAC DINH TAN SUAT NiyC NU'dC BE BI^N HIEN CO Dfi DANH GIA TAN SUAT VUOT TAN SUAT THI^T Ke VA XAC D|NH CAC T6 HgP SONG, TRltU VA NUaC DANG CO THt XAY RA TRONG VilNG BISN NU'dC TA CHU NHIEM BE TAI GS.TS.Ngd Tri Vieng BAN CHU NHIEM CHl/ONG TRINH KC.08/06-I0 ^^-f^eg^AN CHU TRI /^, Xl'mSiigxehi hpc TJmy ta BO KHOA HOC VA CONG NGHE Ha ndi, 2010 MVCLVC MGDAU 4 CHUONG 1 6 DE BifiN VIET NAM, NHAN T6 ANH HLTONG & KHA NANG ITNG PH6 VOl BlfiN D6lKHfHAU 6 I.I.HSTH6NGD6BI£NVI$TNAM 6 1.1.1. Thyc trjingde bien Viet Nam 6 1.1.2. 'i'eu ciu thiit ki de biin den nim 2010. (Chua xit den tic ddng cua BDKH) 7 1.1.3. Khi nang dng phd cua de biin vdi bi^n dii khi h^u 8 1. Tic dpng cda biin dii khi hiu toin ciu din myc nude bien dang d Vi^t Nam 8 2. Khi nang img phd cua De biin 9 a. Nang cip de bien 9 b. Quy hoach chlin lupcdebiin irng phd vdi myc nude biin dang 16n 9 1.2 HE THONG M6C, CAO DO PHVC VV TINH TOAN Ml/C NUGc BIEN 10 1.2.1. Moc cao do Bic bO - Thanh H6a 10 1.2.2. Mic cao dp Nam bd v4 Tmng bp 11 1.3. CAC TAC NHAN ANH HUONG DEN DIEN BifiN DlTdNG SG BifiN 19 1.3.1 Quan h? tuong tic dong chiy song vdi dien bien dpng luc viing cda sdng ven biSn Viet Nam 19 1.3.2. Mot si yeu ti ty nhien liSn quan vdi diin bien dOng lye vung cira sdng ven biin ViSt Nam 20 CHirONGII 30 CAC PHUONG PHAP TlNH TOAN Ml/C NlTdC BIEN THIET K£ 30 I. Khai niem chung 30 n. Tinh toan myc nude biin thiet ki 30 2.1 Trudng hppcd tai liSudo dac 30 2.2 Tinh toan rieng rS cac thanh phan rii ti hpp theo mpt qui luit xac dinh di c6 muc nude thiit ki 34 III. XAY DUNG DUONG TAN SUATMirCNlfOCTONG HOP 34 3.1Casddiili^u 34 3.2 Co sd toan hpc 42 3.3 Tinh toan cac d^c trung thiy triiu thiSn van 46 3.4 Tinh toan cac die trung nude dang bao 48 3.5 Xay dung dudng tan suit nude ding b5o 62 3.6 Xay dung dudng tan suit muc nude ting hpp ^ 66 CHUONG 3 '. 71 DUdNG TAN SUAT MUC NUOC TONG Hgp DQC THEO BO BIEN NAM DINH vA CAC TtNH LAN CAN TU THAI BINH T(3l NINH BINH 71 L Gidi thiSu chung 71 II. Dudng tan suit myc nude ting hpp tir Thii Binh tdi Ninh Binh 71 KfiTLUAN 78 TAI LIEU THAM KHAO 79 Md©Au Trong thin gian gan day, cung vai sy bien doi khi h$u toan cau, cac thi?t hai do thien tai co nguon goc khi tugng thuy v3n c6 chieu hu6ng gia tang tren toan the gidi. Cac corn bao co chieu hudng trd nen m^ hon, trd thanh nhung sieu bSo co sure tan pha nang ne. Cac hi^n tupng mua Idn, gi6 gi$t, loc xoay ciing x^y ra thudng xuyen hon. Cac nghien cOru mdi day nhat tren the gidi cho thay rSng s\r gia tSng byi trong khi quyen do cac hoat d$ng ciia con ngudi da lam bien doi cdc qua trinh nhi$t dpng lyc hpc trong may, tSng khd nSng gdy mua ldn, t6, l6c, voi rbng vd mua dd. Tai nhi^u noi tren the gidi, hi$n tu(?ng dpng dat va song than cung xdy ra thudng xuyen vd gay nhieu h^u qua vo cung nghiem trpng. Hien nay, vdi sir phdt tri^n kinh t^, xa h6i, nhu ciu ddm bdo an ninh qu6c phong ciia cd nude, cling vdi chien lupc vuon ra bien de khai thae mpt each hieu qua hon vung bien nude ta, ngay cang co nhieu ho^t dpng xa hpi, kinh te va qu6c phong tren pham vi toan vimg bien. Dieu do lam tang rat nhieu khd ndng thi^t hai do cdc thien tai thdi tiet gay ra t^i vimg bien vd vung ven bien Viet Nam. Van de ndy co the dupe xem xet tren hai mat. Thtjr nhat la cae hoat d6ng kinh te xa h6i tai vimg bien va ven bien da gdy ra nhiing thay ddi v^ mdi trudng ty nhien theo hudng bat Igi vd 1dm gia tang thien tai va thi?t h£ii ciia thien tai. Viec xdy di^g cdc cong trinh ven bd bien da ngan cdn dong van chuyen bun cdt tu nhien dpc bd, gay ra bdi lap tai cac luong tau va xoi Id bd tai nhiiu ncri. Cac hd chua nude dupe xdy dvmg tai thupng nguon cdc con song ciing ngan ddng van chuyen bun cat ra biSn, 1dm tinh hinh xoi Id bd bien ngay cdng trd nen nghiem trpng. 6 rat nhieu khu vuc, rimg ng$p man va rimg phdng hp ven bien da bi tan phd dd Idy dAt cho cdc ao dam nudi hdi san. Cac rung ngap man vd rimg phong hp bj mit khong nhiing gay ra nhung bien doi ve mdi trudng sinh thai theo hudng cd hai, ma cdn giiip cho sdng ldn ddnh thing vao d6 bien, gay va d6 bien vd ngap lut. Nhiing diiu tra sau can bao so 7 (bao Damrey) ngay 27/9/2005 cho thay nhOng khu vuc rimg ngap man va rirng phdng hp ven bien cdn dupe bao vp tdt thi de bien khong bi vd. Thur hai la cdc ho^t dOng kinh te xa hpi tren biin vd vung ven bien da t^o nen su tap trung rit cao vl cac cdng trinh xay dyng va tai sdn cd gia trj cao ciing nhu dan cu d vung ven biin. Diiu ndy ciing lam gia tang miic dp thi^t hai m^t khi thiSn tai thdi tiet xay ra. Thi du, con bdo so 7 (Damrey) nam 2005 cung vdi gid manh da gay song ldn vd nude dang t^i vimg bd biin ciia nhiiu tinh thupc viing ven biin Bac Bp nhu Hdi Phong, Thai Binh, Nam Dinh, Ninh Binh, Thanh Hoa. Song ldn, nude ddng kit hpp vdi trieu cudng da 1dm va de tai nhiiu vj tri, gay thiet hai vl kinh te xa hOi hdng ngan ty ddng. Gin day nhat Id con bao Chan Chu tuy khong xdy ra trong viing bien nude ta, nhung da lam dSm nhieu tau danh bdt xa bd va 1dm nhiiu ngu dan thi^t meing. M^c dii chua dupe khdng dinh vdi cac bdng chiing day dii, nhung mpt so kit qud phdn tich gin ddy da cho thay rang bien doi khi han dang 1dm gia tdng thien tai. Trong nhimg ndm gin day, nhihig can bao co cudng dp sieu m^mh tren bien dudng nhu ngdy cdng trd nen pho bidn vd gia tang siic tan pha doi vdi kinh tl, xd hpi vd mdi trudng tren pham vi toan thi gidi. Chi trong khodng 15 ndm gin ddy, tai khu vyc Nam A da xuat hipn 2 can bao ldn, giet hai hdng trdm ngdn ngudi. Ndm 1993, mpt can bao do bp vao Bangladesh da gay nude dang 1dm 138.000 ngudi chit vd mat tich va gay nhihig thi?t hai vd cung to ldn vS tai san. Gan ddy nhat, vao dau ndm 2008, con bao Nargis do bp vao Mien Di?n kem nude dang tdi 6m da lam khodng 140.000 ngudi chit vd mit tich. Ddc bi$t, tran sdng than ngay 26 thang 12 nam 2004 tai An Dp Duong da lam chit gin 300.000 ngudi vd hdng trieu ngudi mat nha ciia. Bao manh thudng k^m theo nude ddng bao. Trong trudng hpp nude dang bao xdy ra ddng thdi vdi triiu cudng, mye nude cao giup s6ng ddnh true tiep vao de bien, tran qua de gay xdi Id vd cd thi v5 de, gay ng|ip lyt tren dipn r^ng va thiet hai rit ldn cho vimg ven bien. Vi vay, can co mpt nghien ciru xdc dinh lai tin suat myc nude de bien hien cd de ddnh gid tan suit vupt tan suat thiet ke va xac djnh cac to hpp sdng, trieu vd nude dang ed the xdy ra trong vimg bien nude ta. CHUONG I Bt BIEN VH:T NAM, NHAN T6 ANH HUdNG & KHA NANG (TNG PH6 Vdl BI4N B6I KHi HAU 1.1. Hf TH6NG Bf; BliN Vlf T NAM Hien nay, Vi$t Nam cd khoing tren 2800 km de bifo thu^c 28 tinh vi Thinh phd, bio ve khoing 0,70 trieu ha dat canh tic, BChu dd thi, Khu cdng nghiep, Cing vdi khoing 5 tripu dan. Trong dd 85% song bing ndng nghiep. Vi vay, chinh sich xay dyng, tu bo, cung co he thong de bien li mpt chien lupc rat quan trpng trong vipe phit trien kinh te xi h0i ben virng, djc bipt li kinh tS bien d nude ta. Xay dyng de bien vira li bien phip phdng, chong vua li thich dng vdi bao lut, nude biSn ding vi xam nhip min. Nude ta, nim 1410 bit diu dip de biin. Tai Ninh Binh, nam 1471, de Hdng Ddc cb^y td Bic Yen Md den Phung Cdng, nim sau trong dat lien each bd biin hipn nay 25km. Be bien thu hai dupe dip nim 1830 d Than Phu - Dien Hp cich con de thu nhat khoing 8km vdi thdi gian lan bien dii den 369 nam. Con de thu ba tien ra bien them chimg 7,5km dip vio nhihig nam 1830 - 1927 (97 nam). Con de thu tu dip vio nam 1959 (32 nam sau) tiin them ra bien 8 km nila. De bi6n Thanh Hoi, Hi Tinh va Bmh Dinh (De Ddng) dupe hinh thanh tu nhiing nam 1929 - 1930. Hiu h6t de bijn, de cua sdng cac tinh MiSn Trung va Nam Bp dupe dip khoing trudc va phan ldn li sau nam 1975. De biSn li h6 thdng dap, cdng, ke, de (bing dit, di, beton cdt thep ) ngin man bio ve cda sdng, bd bien, khu dan cu vi nhihig boat ddng kinh td ven biSn vi dim bio an nmh qude phdng. Khic vdi de sdng, de biin lim vipc thudng xuyen hang ngiy cdn de sdng chi lim viec theo mua lii. Bd bidn nude ta dai 3354 km, song mdi ed 1400 km de t^c tiSp vdi biin vi khoing 1400 km de cda sdng, chiim 42,3%. Trong dd hai ttah Nmh Thuan vi Btah Thuan cd thi coi nhu chua cd de bien (Ninh Thu^n cd 6,23 km, Bmh Thuan cd 10,71 km de biin song phin ldn la de cda sdng Cii Phan Rang, Phan Thiit vi ke Mui Ne). 1.1.1. Thyc trang dS bien Vi?t Nam. a. Hiu hit dip bing dat (de lin bien, ngin min), do din ty xay dyng, chu ddng, song thiiu qui ho?ch, nin dit yiu. Theo chu ky lin biin da t?o ra nhi$u M thdng bio vp trong vi ngoai. b. De beton hay beton c6t th^p (d6 chong bien ldn) phin ldn do Nhd nude lam song do thiiu qui hogch, bi dpng, nin dat yiu, tuyin de thudng kh6ng phii hpp vdi tuydn chinh tri nen nhieu lin bi pha, ddp lai vd nhieu lin di ddi, luon ludn la noi lo. c. Chua dap ling yeu ciu thiit kl. 1) Dinh cdn thip: So vdi yeu cau cao trinh dinh hau hit cdc tuyin de cdn thieu khoang 0,5 ~ 1,0 m. 2) Chat lupng de bien con thip do v|it li?u ddp (phan ldn la dat boi, dit cat) thiet bi ddp, ky thuat dap khdng ddp ling yeu ciu thiit kl. 3) Dp rdng mdt de cdn thieu tir 2 ~ 3 m. 4) Nhiiu tuyin de thiiu hdn rimg ng|ip m^ do phd dl nuoi torn, chdt cay liy gd, hodc do tan pha bdi chit dpc hod hpc 5) Nhieu tuyen de ngudi dan lin chiem m^t de (biin Tay) 1dm vudn canh tac, nha cua xay cat trong pham vi tuyin de biin 1.1.2. YSu ciu thiit kl d£ bien din nam 2010. (Chva xet din tdc dpng cua BDKH) Hien nay, theo Quyit djnh s6 58/2006/QD - TTg ngdy 14 - 3 - 2006 cua Thii tudng Chinh phii Phe duy?t Chuang trinh dau tu cung cd, bao \& va ndng cap de bien hien cd tai cdc tinh cd de tu Quang Ninh din Qudng Nam: 1) Tieu chuin thiit kl: Trudc mdt den ndm 2010 ddm bao h? thdng de bien cd the chdng dupe bdo cip 9 td hpp vdi triiu cudng tin suit 5%. - Ddi vdi cac tuyin de bao ve true tiep cdc khu vuc dan cu t$p trung phdi dupe thiet kl bao dam an todn chdng gi6 bao cap 12 vdi myc nude triSu tdn suat 5%. - Ddi vdi cac tuyin de ngoai, de bdo v? san xuit, nudi trdng thuy, hdi san thiet ke chdng gid bao cip 9 vdi miic triiu tin suit 5% chip nhan mpt phin song leo tran qua dinh de khi gio bao vupt mure thiit kl nhung khdng gay vd de. 2) Giai phdp ky thuat: - Cling cd, nang cip cdc tuyin de bien, de ciia sdng tao thanh cac tuyin de khep kin kit hpp vdi lam dudng giao thdng vdnh dai ven biin nham bdo v§ ddn sinh, tao ca sd phdt triln kinh tl - xa hpi va ddm bdo an ninh, qu6e phdng; - Chilu rdng mdt de tdi thiiu tir 5,0 m din 6,0 m, de phdi dupe kien cd, gia cd du cao trinh chdng vdi miic gid bao thiit kl (cip 9, cip 10, khu vyc dan cu cip 12 vdi miic triiu tin suit 5%), giam thiiu dupe nguy cp v5 d6 khi bao vupt miic thiit kl; Trdng cay dpc theo tuyin de nhim tao rimg ngip min chin sdng trudc de biin, phai coi diy li bipn phip bit bupc, kien quyit doi vdi tit ci cac khu vyc, tuyen de cd the cdn t-ong dupe ciy chin sdng; ding thdi cii t?o h^ sinh thii viing ven biin; - Doi vdi cic khu vyc biin tiin, xim thyc, ein nghien ciju giii phip cdng trinh cit song, t?o bai boi nhu xay dyng ki md ban, phun cat nudi bii timg budc trong cay chin sdng de dim bio on djnh liu dii; - Cic tuyen de xung yiu tryc di$n vdi bien phii dip them tuyin 2 dy phdng phia trong nham dim bio an toin cho nhin dan, him chi thipt hji khi tuyin I (tayin t^c dien vdi bien) bj vd khi gid bao vupt qui khi ning chong dd ho§c sdng trin qua; - Bo tti cic tayin dudng ngang (dudng xuong ci) dl vira lim dudng so tin dan, cira hp de khi xay ra sy c6 de diiu; cic tayen dudng niy sS cd tic dyng phin vung ven biin thinh cic d khep km, dpc lip, nhim giim thieu di^n tjcb bi ngap lut, nhiem min, h^ che thipt hai khi xiy ra sy co de biin; - Nghien cuu, ung dyng khoa hpc vi cdng nghp phyc vy cung co, bao vp cic tayin de, ke biin vi vvmg cua sdng, xu ly xdi Id, bio vp de, bai phu hpp vdi diiu ki?n ty nhien, thuy, hii vin. sip den, Chinh phu sS cd Quyit dinh phe duypt "Chuong trinh cung cd, ning cip va xay dyng mdi de biin cic tinh tu Quing Ngai din Kien Giang" 1.1.3. Kha ning irng phd ciia de bien vdi biin doi khi hau. 1. Tic dpng cua bien doi khi h^u toin cau den myc nirdc bien ding d Vi^t Nam. Theo nghien cdu ciia chiing tdi thi myc nude biin ding d vimg ven bien Bic Bp vi Nam B0 (biin Ddng) trung binh tang 2-3 mm/nim theo chudi so myc nude biin quan trie dupe trong hon 30 nim (1976 - 2006). Vimg ven biin Trung Bd ting trung btoh 1~2 mm/nam. Nhu viy chung ta ed thi khing djnh din nim 2010 myc nude bien dang khdng qua 10 em so vdi nim 1976. Theo IPCC, din 2100 myc nude biin ding len Im, dipn tich dat bj ngjp: -14520 km^ (khoang 4,4% di|n tich dit cua Vipt Nam). - Trdn 60% hay 39 trong so 64 tinh vi 6 trong 8 vung kinh tl cua Viet Nam se bi inh hudng. - Khoing 20% hay 2057 trong sd 10511 xa tren ci nude se hi ngap mdt phin hoic toinb$. - 85% trong tong qui md ng^ip nude se inh hudng tdi 12 ttoh vi tren dipn tich 12376 km tai vung Dong Bing Sdng Cdu Long. - Ndi m$t cich tong quit, trong thi kj" 21 myc nude bien ting tomg binh 1cm / 1 nim. 2. Kha nang irng phd ciia Be bien. a. NSng cap d€ biin. 1) Thyc iiipn thinh cdng Quyet djnh cua Thu tadng Chinh phii vl vipc nang cip de biin din nim 2010. 2) Tiip tyc nghien ciiu Tieu chuin de biin vi giii phip ky thuit de biin. Bdi vi thyc tl din nim 2010, tic dpng lim ding cao myc nude bien cdn chua ding kl, song din nam 2020, 2050, 2070, 2100 dii rd ring la mpt vin de Idn. Trong khi do, Tieu chuin thiet ke tinh den nim 2010 ehua xet din mdt cich rd rang vl h^u qui nude biin ding len. Trong Tieu chuin chi qui djnh 2 yiu to myc nude dinh triiu ung vdi p - 5% vi gid bao ung vdi cip 9, cip 10, cip 12, khdng cd yiu to nao die trung cho gii trj myc nude biin dang len, mic du trong yiu td myc nude trieu 5% cd thi cd hin quan song khdng dang kl. 3) Gid bao ciing li yiu td chiu tic ddng cua biin doi klii hiu do lim tang cudng dp vi tin suit xuit hi^n song chi ed tic dung nang cao sdng bien tic thdi. Vi the, trong Tieu chuin thiit kl de biin khdng nen gia tang cip gid bao qui ldn (cd thi cip 12 li dil). NIU qui Idn thi ldn din diu? trong khi xu thi bao ngiy cing tang mi thdi gian gay hai thi rit ngin ed thi cho sdng biin trin qua nhung khdng cho phep di vd. Hien nay khoa hpc cdng nghp hien dji thi gidi vi ngay d nude ta diu cd thi giii quyet. 4) Qui hoach vi xiy dyng mdi he thdng de biin tir Quing NgSi - Kien Giang bio dim cic tuyin xudi thu$n, nin mdng vihig, v$t lipu phu hpp, ky thuit xiy dyng hipn dai an toin. Diy li hp th6ng de biin cd d$ an toin thap nhit nude ta song s8 bio v? nhiing vung bi nggp nhiiu nhat nude ta. 5) Xay dyng hp th6ng de biin thinh mpt hp thong giao thdng quic gia ven bien dim bio an ninh quoc phdng c6 rimg ngip min phdng h$, bio v$ mii. Cic vimg ed dieu ki$n cho pMp cin xiy dyng tayen de 2, dy phdng, thuin lpi cho vi^c so tin din khi cd sycddtaydnde I. b. Quy hoach chiln luprc dS biin ihig pho vdi myc oirdc biin dang ISn. 1) Dinh gii dp tm ciy cda cac kich bin biin d6i khi hiu. 2) Danh gia tinh kha thi ciia chien lupc toan cau doi pho vcVi bien doi khi hau, giu nhiet dp tang d miic 2°C va giii miic 450 ppm CO2 vao nam 2050. 3) Qui hoach Chien lupc cap thoat nuac nuoi trdng thuy, hai san trong do khong loai tru bien cac cua song ven bien thanh to hpp tren ciu dudi cong ngdn trieu, man, giii ngpt, thoat lii, giao thong thuan lpi. 4) Chien lupc de biin can xet theo quan diem phat trien lau ben kinh te viing, ket hop hiiu ca giira kinh te bien va kinh te dat lien va chien lupc dam bao an ninh quoc phong. Can cd qui hoach de bien vdi tam nhin xa 20 nam, 50 nam, 70 nam va tinh chat pham vi xem xet rpng ldn hem va khong on djnh so vdi de song vi no anh hudng ciia cac cira sdng. ciia dia hinh - dja mao lan can, dong thdi chiu tac dgng ciia nen dja chat tren toan tuyen. Ddc biet la chju tac dpng ciia bien doi khi hau sau sac. Da den liic can nhan thuc de bien co mpt vi tri chien lupc, Id sir ton vong cua quoc gia. 1.2 HE THONG MOC, CAO DO PHVC Vy XiNH TOAN Ml/C NlT^C BI£N 1.2.1. Moc cao do Bac bp - Thanh H6a Theo thong ke co the ke den loai moc cao do: (1) Cao dp luc dia do Phap xay dung gpi tdt la sd "0 luc dia" lay tning vdi muc nude trung binh nhieu nam chuoi quan trdc muc nude tai Hon Dau. Anh 1: M6C Qude gia tai Hon Dau (2) Cao dp hdng hai do Phap xay dung gpi tdt la sd "0 hai dd", liy tning vdi muc nude rdng thip nhit co thi xdy ra trong chudi quan trie muc nude tai Hon Dau. Tir nam [...]... Nam bp v i Trung b$ Trong myc niy can giii dip ba van de: 1 Trong vung cd miy lo?i mdc cao d$ vi quan h? giiSa chung Sy nhan dang va so dd he thdng cic loai moc dd 2 Myc "0" Thuy van (Hang giang - HG) vi mdc "0" ddng mdng (Lyc dia - LD) 3 Myc "0" mit dit vi myc "0" cua bin dd 1 Cic moc cao dp trong ving - Quan h | giii-a chiing Sy nhan d^ng vi so dd b$ thong cic loai mdc dd Thdng qua cac tii lieu thu... ddnh gia anh hudng ciia yiu to ddng chdy lu din de viing cira sdng cin xem xet nd trong mdi quan he tuorng tdc vdi cac yeu td d^ng lire khdc viing ciia sdng ven biin So dd phdn viing miia lu, miia can ven biin Vi^t Nam dupe thi hi?n trong bang 1.3 Trong bdng tai c0t thii 3, tii so la miia lu, mau so la miia can, sd La MS trong ngo^c dom Id thdng mua lu, miaa can theo chi ti6u "vupt trung binh", ngodi... t i n h gay ra sai sdt trong tinh toin - Su dyng tii lipu thyc do ciia cic tr^m thuy vin d cda sdng ven biin Cic tram niy thudng nim siu trong sdng vi chju inh hudng Idn ciia lu sOng vio miia mua lu, nhung l^i cd thi^n lpi la cd h? cao dp di dupe dua vl chuin quoc gia Do cic t ^ quan trie thih toin tin suit thuOc khu vyc cda sdng vimg trieu, chiu inh hudng ddng chiy sdng nen trong tinh toin chung tdi... nhit Cde mye tieu dupe diic theo timg khdi try beton - H? thong mdc Nam Triiu Ti6n, hi^n rit it, con le te d mOt so vung quanh Thanh phd Hd Chi Minh Trong 7 he thdng neu tren, he thing mdc cao dp ciia Nha Dia du Qude Gia (Ba Lat) NGD hoan chinh hon ca Thdi gian xdy dung h? thdng NGD khoang 8 ndm Ndm 1964 - 1966 thiit lap va do d^c dia hinh; Nam 1964 - 1968 tinh toan vd tir cudi nam 1968 kilm tra lai... +1,00 Rach Gii dau cpc 1 -2,54 Qua so sinh mic HG vi mic NGD, ein bing myc nude fen cimg tayin sdng, giira sdng vi npi dong, thay ring cic myc NGD ngoii trj sd cao dp dupe ghi trong vin bin, chung tdi nghi ngd li cdn cd so hipu chinh chenh Ipch rieng cho tdng vimg quy ude, hay li sy nhim lin sai sdt (3) Vi dy Trim Thily vin R^ch Gii, theo moc Hansi 133 - Xn - C tinh theo NGD (trong sin cdng quin R^ich Gii)... 4,00 = 1,881 va cao d0 diu cpc se li: 1,881 - 0,789 = 1,092 hay H(o) = -4,908 ~ -4,91 b Tram Qui Nhon 1) Nam 1983 Thing I.VII, quan ttic d tram cu (bd ta) cao dp gia dinh R„: 5000 VIII - XII quan t i c 6 tram mdi (bd hChi), cao dp gia djnh R„: 3433 Tram cu va moi cich nhau khoang 500m Nam 1983, do ddng thdi t^li 2 vj tri tren 20 ngay 24/24h/ngay cung he thing cao dp gii djnh, chenh Ipch AH cho phep... Tiu dupe quan trie trong khoing thdi gian do Cic myc tieu bing cac chdt sit trdn, cd mpt tim bing chi trdn dd ghi ddng chO: "Rivellement General De la Cochmchme" cao d0 vi sd li^u ghi hdn cpih myc tieu 2) He thdng bmh chuin d?c Hansi vi Lefebre do Sd Cdng chinh thiit lap vio nim 1938 - 1944 dCmg chung cho ci miin Trung, Tiy Nguyen vi Nam Bd liy theo myc nude biin ttung btoh tji Miii Nai dupe quan trie... tji Miii Nai dupe quan trie bing "thuy chi" trong cic nim dd Cac m\ic tieu bdng chdt gang diu trdn hay Id dinh tan bdng ddng dd, cd ghi so lipu ben canh mue tieu, tuy nhien cd vdi myc tieu khdng ghi so Upu Vao ndm 1967, Cye Do d£ic quan dodn cdng binh My cd d§t them mpt h? thong moc cao dp t$p trung chu yiu d xa Ip BiSn Hda, Lien tmh Ip 15, quoc Ip 15 khu quan sir cua My nhu kho Long Bmh, khu Long... che vl dp dai ciia so li$u quan frdc, ciing nhu dp dung cdc md hinh xac suit thong ke Tii kit qud phdn tich cdc sd lipu do dgc muc nude timg gid frong thdi gian cd bao hogt dpng tai mpt sd fram hdi vdn ven bd da chi ra rang nude dang do bao cd thi xdy ra d bat ky pha frieu ndo, tir do cd the coi hai qua trinh muc nude do trieu thien van va do bao la d^c lap Tinh dpc lap eiia 2 qua trinh nay cho phep nghi6n... theo NGD (trong sin cdng quin R^ich Gii) lai phii -1,00m mdi cin bang myc nude so vdi tii ii^u cu d Gd Diu Ha ciing v|y - nlu liy theo moc cao dp hien tai thi myc nude cao nhit trong miia lu tai Gd Diu Ha chi S^t tdi + 1,60m, trong khi dd t^i Mdc Hda, hay tai cac vi tri d Cu Chi, Hoc Mdn myc nude ldn nhit diiu tra dupe diu ldn hon +l,60m thim chi dat tren +2,00m Chiing tdi cho kilm t a Iji mdc NGD tai . -14520 km^ (khoang 4,4% di|n tich dit cua Vipt Nam). - Trdn 60% hay 39 trong so 64 tinh vi 6 trong 8 vung kinh tl cua Viet Nam se bi inh hudng. - Khoing 20% hay 2057 trong sd 10511 . nd trong mdi quan he tuorng tdc vdi cac yeu td d^ng lire khdc viing ciia sdng ven biin So dd phdn viing miia lu, miia can ven biin Vi^t Nam dupe thi hi?n trong bang 1.3. Trong. s& khoa hgc va de xuat cdc gidi phdp klioa hpc cong nghe bdo ddm sir on dinh vd dp ben cua de bien hien cd trong trie&ng hap sdng, trieu cirdng trdn qua de"