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DI£N DAN PHAT TRI£N NGANH.•^^ ^^ jt
^MQT SO VAN DE VE XAY Dl/NG
C 6 N G TRINH THUY VUNG CUTA SONG VEN BIEN Ci NAM DjNH Q N G PHO V6l
BIEN DOI KHI HAU
* TS. Tran Van Sung TrUdng Dq\ hqc Xdy DiJng TOM TAT
He thdng cong trinh thCiy vung ciJfa song ven bien 6 Nam Dinh da va dang CO vai tro quan trpng, dong gop nhQng ldi ich Idn cho nen kinh te cua tinh.
Trong nnot ti/ong lai khong xa, diTdi tac dong cua bien ddi khi hau thi he thdng nay la ddi ti/png de bj tdn thiTdng nhat. De Lfng pho vdi nhOng tac ddng do, bai viet nay phan tich toan dien cac van de lien quan tdi i n h hi/dng cuia bien ddi khi hau va tac dong cua no ddi vdi cac cong trinh thuy xay diTng d vung cufa song ven bien. TCf dd de xuat djnh hi/dng cac g i i i phap ufng pho khi nghien cufu thiet ke cac cong trinh nay trong dieu kien mdi tren dja ban Nam Djnh
ABSTRACT
The hydraulic structure systems of the Nam Dinh's coastal estuary have had important role and given powerful benefits to the province's ecomomy. In the near future and under the impacts of Climate Change, these systems w i l l be very easy to come to harm. In order to deal with those effects, this paper generally analises problems which concerning to influences and impacts of climate change on hydraulic structure systems on the area of coastal estuary. This paper is also to set up some solutions when making the hydraulic structure designs in the new conditions on the Nam Dinh area.
I. va'n dl bid'n dd'i khi hau va nrfdc bidn va dSng cao
Bid'n ddi khi hau todn clu dang vd sd Id yd'u td' cd tim anh hfldng Idn, tdc ddng manh me ddn mpi ngdnh, mpi ITnh vflc dac biet la nhflng Qudc gia cd bien nhfl Viet nam. Vidn Khoa hpc va Cdng trinh thuy - Trfldng Dai hpc Xay Dflng la ddn vi nghidn cflu, thidt kd' cac cdng trinh tfl thfldng ngudn ra bidn; chflng tdi 5' thflc dfldc nhflng gi phai dd'i mat vdi bid'n ddi khi hau. Theo tai lidu "kich ban bid'n ddi
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DI£N DAN PHAT TRI£N NGANH khi hau, nfldc bien dang cho Viet Nam":Vl Ifldng mfla: Lfldng mfla mfla khd cd the giam d hlu hd't cac vflng khi hdu cua nfldc ta, ddc biet Id cdc vflng khi hdu phia Nam. Lflpng mfla mfla mfla vd tdng Ifldng mfla ndm cd the tdng d ta't ca cdc vflng khi hau.Theo kjch ban phdt thai tmng binh; vdo cudi the' ky 21, Ifldng mfla cd the tdng khoang 7-8% d Tay Ble, Ddng Ble , Ddng bang Bac Bd, Ble Tmng Bd vd tfl 2-3% d Nam Tmng Bd, Tay Nguydn, Nam Bd so vdi tmng binh thdi k^ 1980-
1999. Lfldng mfla thdi ky thdng ba dd'n
thdng ndm se giam tfl 4-7% d Tay Ble, Ddng Ble, Ddng bang Bac Bd, khoang 10% d Ble Tmng Bd vd khoang 10-15% d cdc vflng khi hau phia Nam so vdi thdi ky
1980-1999, Lfldng mfla cdc thdng cao diem mfla mfla sd tang tfl 10 dd'n 15% d ca bd'n vflng khi hau phia Ble vd Nam Tmng Bd, cdn d Tly Nguydn va Nam Bd chi tdng xd'p xi 1%. Nam Dinh thudc vflng ddng bang Bac Bd cd phan bd' Ifldng mfla nhfl Bang I. Hidn tfldng ngap lut do mfla lu tap tmng dang ngdy cdng phd bid'n nhfl hinh anh trdn
Bang 1: MiJc thay ddi Irfgfng mifa(%) so vdi thofi ky 1980 -1999 d cac vung fchi hau cua Viet Nam theo cac kich ban phat thai trung binh Vung
Dong bang Ble
Bo
Thofi ky trong
ndm XII-II
III-V VI-VIII
IX-XI
Cac mdc thdi gian cua thd' ky 21
2020 0.9 -1.3
2.9 0.9
2030 1.2 -2.0
4.4 1.4
2040 1.8 -2.7
6.1 1.9
2050 2.3 -3.6 7.9 2.5
2060 2.7 -4.3
9.6 3.1
2070 3.2 -5.0 11.1 3.5
2080 3.6 -5.7 12.6 4.0
2090 3.9 -6.2 13.9 4.4
2100 4.3 -6.8 15.1 4.8 v l nIn nhiet, bid'n ddi khi hau md bieu hidn trflc tidp cua nd Id nIn nhiet tdng cao vd hau qua cfla nd Id 1dm bdng tan d hai cflc, khidn nfldc bien ngdy cdng dang cao. Canh tfldng bdng tan d Ble cflc thfldng tha'y nhfl anh bdn. Nam Djnh thudc vflng ddng bang Ble Bd theo kjch ban phdt thai tmng binh, nIn nhiet bid'n ddng trong cdc thdng vdi cdc mdc thdi gian dfldc thd'ng kd trong Bang 2
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DI£N DAN PHAT TRI^N NGANHBang 2: Mflc tang nhiet dp trung binh ( OC) vdi thofi ky 1980-1999 d cac vung khi hau cua Viet Nam theo cac Rich ban phat thai trung binh
Vung
Dong bang Bac
Bo
Thdi ky trong
nam XII-II
III-V VI-VIII
IX-XI
Cac md'c thdi gian cue thd'ky 21
2020 0.5 0.6 0.3 0.4
2030 0.8 0.9 0.5 0.6
2040 1.0 1.2 0.7 0.8
2050 1.3 1.7 0.8 1.1
2060 1.7 1.9 1.1 1.3
2070 2.0 2.3 1.3 1.5
2080 2.3 2.5 1.4 1.8
2090 2.6 2.9 1.6 1.9
2100 2.8 3.1 1.7 2.2 v l nfldc bid'n dang, theo kd't qua tinh 21 cd the dang thdm khoang 75cm so vdi todn vdi kjch ban phat thai tmng binh; vdo thdi ky 1980-1999. Cdc kjch ban nfldc bid]n gifla the' ky 21, mflc nfldc bien d Viet Nam dang d Viet Nam dfldc dfl bdo theo Bang 3 cd thd dang thdm 30cm vd dd'n cudi thd'ky
Bang 3: M\ic nfldc bidn dang (cm) so vdi thofi ky 1980-1999 Kich ban
Thap(Bl) Tmng binh (B2)
Cao (AlFI)
Cac mdc thdi gian cua the' 202
0 11 12 12
2030 17 17 17
2040 23 23 24
2050 28 30 33
2060 35 37 44
2070 42 46 57
ky21
2080 50 54 71
2090 57 64 86
210 0 65 75 100 IL Tac ddng bie'n ddi khi hau va niTdc
bidn dang tdi cac cdng trinh thuy vung cfla sdng ven bien
Bid'n ddi khi hau lam tang lfldng mfla vl mua mfla va mfla tap tmng vao thdi ky bao lu gay ra ngap hit cho vung cfla sdng, tran va vd dd cfla sdng
Mflc nfldc bidn dang cao lam cho bai sail hdn, rCrng ngap man sd bj ngap thdm tao dilu kidn cho song truyin ddn cdng trinh Idn hdn, pha buy cdc kd't can vdn da dfldc thidt kd trong cdc dilu kidn han chd' tnrdc dd.
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DitN D A N P H A T T R I ^ N N G A N HHidn tfldng bien lan thfldng tha'y nhfl anh bdn
Mflc nfldc bien dang cao kd't hdp vdi trilu cfldng cd the gay tran thdm nhilu tuyd'n dd (ddc biet Nam Djnh cd he thd'ng dd bidn vd dd cfla sdng dai dd'n hdng trdm km), uy hid'p cdc nganh kinh td' ven bien nhfl ndng nghidp, ngfl nghidp, du Ijch, giao thdng van tai
Nfldc bid'n dang cao cung cd the lam ngap cdc cang bid'n, cang cfla sdng, cdc cdng trinh ddng tau. Nam Djnh cd cdc cang Hai Thjnh, Ninh Cd,... la nhflng vung se trflc tidp ehju anh hfldng
Dai da't vung cfla sdng ven bien d Nam Djnh ddc biet la vung Hai Hau, Giao Thuy Id nhflng vung bien hd tfl tnrdc dd'n nay vdn da bj bien lan tfldng lai se cdng bj uy hid'p tram trpng hdn bdi cd nhilu dd bien, dd cfla sdng
Tfl nhflng nhan thflc dd, qua thflc tiln nghidn cflu, thid't ke, dfldi day chung tdi xin d l cap mdt sd va'n d l mang tinh djnh hfldng cho vide xay dflng cdng trinh thiiy vung cfla sdng ven bidn d Nam Djnh flng phd vdi nhflng dilu kien ba't ldi do bid'n dd'i khi ban gay ra.
i n . Mpt sd' de xua't giai phap trong xSy dflng cdng trinh vung ciJa sdng ven bidn of Nam Dinh U'ng phd vdi bid'n ddi khi hau
Mpt la ve quy hoach: dd xac djnh quy md, vj tri cdng trinh dd ke c i n xem xet tdng the cdc bid'n ddi v l mfla, bao, lu va nfldc bidn dang cu the:
Vdi dd bien Nam Djnh ddc biet la de Hai Hau cin quy hoach lai tuyd'n dd dfl phdng
Vdi cdc cang cu cd cdc phfldng dn cai
vdi cac cang xay dflng mdi, khi xdc djnh cao trinh dinh ben phai tinh dd'n dfl tifr do mflc nfldc bid'n dang.
Vdi he thd'ng ke cfla sdng vide xdc djnh cac tuye'n mdi phai quy hoach theo ban dd ngap hit phu hdp vdi giai doan theo kjch ban BDKH dfldc lira chpn
Hai la ve khao sat thid't kd': de flng phd vdi bid'n ddi klii hdu cdng tdc khao sat thid't kd'can phai cd nhflng nhan thflc mdi:
Doi vdi cong tdc khao sdt, ddc biet chu trpng cap nhat, bd sung nhflng thay ddi vl khi tfldng, thuy vdn va hai van, cd phan tich, ddi chieu vdi cdc sd' lieu da dfldc dfl bao theo kjch ban bid'n ddi khi hau, nfldc bidn dang cho Viet Nam
Ve xdc dinh tdi trong, phai xdc djnh tai trpng sdng, ddng chay theo cac kjch ban v l bie'n ddi mflc nfldc tai cdc bien cdng trinh, cu the. Vdi cdng trinh cang bidn, cang cfla sdng, dd sdng, dd bien khi xdc djnh tai trpng sdng phai tinh vdi mflc nfldc tinh toan theo tidu chudn thid't kd hidn hanh cdng thdm gia sd mflc nfldc bidn dang do bidn ddi khi hau.
\e ket cdu cong trinh: cdn phai bao dam linh boat trong bd sung, dilu chinh de cd the gia cfldng, tdng ndng Iflc ehju tai, cu
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DI£N DAN PHAT TRI£N NGANHthd:
-I- Vdi cang bidn, cang cfla sdng do phai Idm vide trong dilu kidn chilu sau nfldc tang, sdng cung Idn hdn cin chu trpng gia cd' mat bdn, ehd'ng sdng phan dp
-I- Vdi dd bien, dinh dd ndn cd tfldng hit sdng, trdn mat dd cd mdng tidu nfldc vd mat cat dd cd nhilu thIm giam sdng, de linh hoat bd sung cdc ldp tidu sdng Id nhflng giai phdp hflu hidu. Anh bdn trdi la mdt la mdt de bidn da dfldc xay dflng vd phdt huy tdc dung ma Nam Djnh cd the dp dung
-I- Dd'i vdi dd cfla sdng, khi thid't kd' mat cat cdn tinh tdi cac dfl trfl bl rdng de cd the dp true, nang cao.
-I- Dd'i vdi ke bd sdng, bd bien bao vd cdc kliu du Ijch, khu cdng nghidp tap tmng, kliu dan cfl vide Ifla chpn cao trinh dinh, cao trinh cd, ldng the tfla cin phai tinh tdi cdc dilu kidn tang cao mflc nfldc theo kjch ban bid'n ddi klii ban
Ve vdt lieu: trdn cd sd cdc vat lieu thdng dung nhfl sat thep da't da, xi mang nhfla tdng hdp, cao su... cd the tim kid'm cac giai phdp kd't hdp trong xay dflng cdng trinh vung cfla sdng ven bien, cu the:
-I- Vdi dd bidn, ke bidn, do mflc nfldc
dang cao thdm, sdng cung Idn hdn ndn klidng the dung cdc ca'u kidn dang td'm md phai tinh dd'n cdc kd't ca'u dang khd'i Idn, khd'i rdng de tidu sdng, khdi dj hinh cd he sd'dn djnh cao. Trong nhflng ndm gin ddy, vdi cdc thid't bj hidn dai, chung ta da chu ddng chd tao, lap ddt cdc ca'u kidn Idn anh bdn Id mdt thflc td'.
-I- Vdi ke bd sdng, bd bidn ndi cd sdng nhd cd the sfl dung tham bd tdng, tham dd, cfl thep, cdc khd'i be tdng dflc sdn dang mdi cd sfl cai tid'n lidn kd't gifla cdc khdi, tao them dp rdng de tidu sdng
-I- Anh dfldi gidi thieu mdt so' mau khd'i mdi dfldc dl xua't bdi d l tdi Dl tdi B2009- 03-63 cap bd
Khdi A
Khdi B
Khdi C
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S6 11+12-Nim 2011MSien^ b d
DI£N DAN PHAT TRI£N NGANH - Ve an todn cong trinh: vdi cdc cdng III. Kd't luantrinh da xay dflng, khi bd sung, sfla chfla, 1. Vdn dl bid'n ddi khi hau todn.clu da nang cap cin ddnh gid lai mflc dp an todn; va dang ddt ra mdi quan tam sau sac cua vdi cdc cdng trinh xay dflng mdi cin kiem tat ca cac nganh, cac linh vflc cua nIn kinh tra dn djnh theo nhflng td hdp tai trpng td'd nfldc ta.
dfldc xdc djnh tfl nhflng yd'u td bat ldi do 2. Nhflng tdc ddng bat ldi cua bidn ddi bid'n ddi khi hau gay ra. khi ban ddi vdi he thdng cdng trinh thuy -I- Vdi cdc cdng trinh thuy xay dflng d ven bid'n d Viet Nam trong dd Nam Djnh vung cfla sdng ven bien dac biet la vung la vung bj anh hfldng trflc tidp mang tinh bid'n hd d Nam Djnh, vide Ifla chpn tin lau dai va ngay cang klidc liet
suat mflc nfldc cao thie't kd' nd'u lay dfla 3. Cac dl xua't giai phap md chung tdi trdn nhflng tai lieu quan trie da cd phai da ndu sd gdp phin djnh hfldng cho cdng cdng thdm trj so nfldc bien dang do tdc nghien cflu, thid't ke', va xay dflng cdc BDKH, la'y dd 1dm cdn cfl tinh sdng, ddng cdng trinh thuy vung cfla sdng ven bien d chay, chuyen ddng bun cdt, danh gid dn Nam Djnh
djnh cua cdng trinh
IV. Tai lieu tham khao
1) Kjch ban bid'n ddi khi hau, nfldc bien dang cho Viet Nam. Bo Tdi nguyen vd moi trudng ,Ha Ndi, thdng 6/2009.
2) Chfldng trinh muc tidu qudc gia flng phd vdi bidn ddi khi ban (Quyd't djnh sd 158/2008/QD-TTg ngay 02/12/2008 cua Thu tfldng Chinh phu ).
3) Bid'n ddi klii hau NXB Khoa hgc vd ky thuat. Ma so: VN/05/009.
4) Tai trpng va tdc ddng (do sdng vd do tdu )ldn cdng trinh thuy tieu chudn thie't ke, Bp Giao thdng van tai, 1995.
5) TS. TrIn Van Sung - Nghien cflu cd chd phd hoai ldp gia cd mdi dd bien, dd xuat giai phdp kd't ca'u hdp ly, nang cao dp dn djnh cua can kidn ehdng sdng trong dilu kidn Viet Nam - Dl tdi B2009-03-63 cap bd
