Đang tải... (xem toàn văn)
NhIm han ehi su phat trien eiia su e l , edng trinh tam ngdng mot thdi gian trong luc chd tim nguyen nhan, ehii diu tu da ky hgp ddng vdi Cdng ty Ddng Minh (TQ) thi c6ng khoan phut x[r]
(1)DIEN DAN KHOA HOC CONG NGHE ^
BAI HOC Tir SU CO SAP DO VIEN KHOA HOC XA HOI
V O N G N A M BO Of THANH P H H 6 CHI MINH
P G S T S N G U Y E N B A K E
Hoi C d h o c d a t v a D j a ky t h u a t c o n g t r i n h V i e t N a m
Viec too nha Vien Khoa hoc Xa hoi vung Nam bo tgi ^ pho Ho chi Minh sgp khoang 19 gi5 thdng 10 nam p 2007 CO lien quan nhu the nao v6i viec thi cong phan tang
ngam cua cao oc Pacific ben cgnh, cho den van chua co su phan tich ky ludng ve mat 1^ thugt de til rut ro mot so fi bai hgc nham phong trdnh su co tuong tu tuong loi S Bdn bdo cdo ndy thiJ co gang Idm viec tren co s6 nhung tu P
lieu dd thu thgp dugc H
1 Vj trf va quy md cong trinh
C6ng trinh cao l e Pacific n I m tai s i nha 43-45-47 Nguyin Thj Minh Khai, phudng B i n Nghe Q.I, TP H6 Chi Minh; phia Bde t i i p gidp toa nha YOCO eao 12 tang eua bao Tuoi tre, phia 06ng Bde t i i p giap dudng Nguyin Thj Minh Khai, phia D6ng Nam t i i p gidp toa nhd t i n g eua Vien Khoa hoe Xa hoi vung Nam bg, phia Tay gidp Sd Ngoai vu (hlnh 1)
Kit ciu cong trinh: Toa eao l e Pacific dugc cap phep xay dung thdng 2/2005, dien tich mat bing 1.750m^ cao 78,45m, ba t i n g h i m vd ting ky thuat (ehilu sau 11,8m); tret vd 20 t i n g l l u ; tong dien tich sdn xay dung la tren 22.000m^ Tuy nhien qud trinh thi e6ng, chu d i u tucao l e Pacific da d i i u chinh thiit k l (chua dugc Sd Xay dung thdnh p h i cho phep) len thdnh sau ting h i m (ehilu sau 21,1m), mot t i n g tret, 21 llu, tong dien tich san xay dung len tdi hon 41.000m^ vdi he khung g I m 16 egt ed t i l t dien 1400x1400mm va san ngang
N§n mong cong trinh: Cdng trinh s d dung mong be BTCT ddt tren 65 cgc barrette kich thude 2,8x1,2m sau 67m Theo thiit k l , he tudng vay g I m 50 t i m panel kich thude td 2,8 d i n 5,7m, day I m sau 45m nhung thi c6ng cong ty PACIFIC da thay doi 24 panel kich thude 2,8 d i n 7,7m, day I m sau 45m Gioang each nude gida cac t i m panel khong duge ehi djnh ehilu ddi thiit k l nen dorn vj thi c6ng ehi dat d i n ddy t i n g h i m , tdc khoang 22m
Thi c6ng cdc t i n g n g l m theo phuong phdp "bdn nguge" (semi top-down) sd dung he chdng dd ngang la he d i m san BTCT day 236mm va 250mm tua len cot bien tao he c h i n g ngang
Hinh Bia diem cdng trinh cao dc PACIFIC
phia tudng vay
Chu d i u t u va q u ^ ly du an: Cdng ty TNHH mot vien Bia Thai Binh dutrng;
Don vj thiit k l f^ao l e : C6ng ty T u v i n xay dung dan dung cua Bg Xay dung;
Don vj thi e6ng: Chu d i u t u t u to chdc thi e6ng; Don vj tu v i n gidm sat: chij dau tu tu Idm;
Don vj chdng nhan c h i t lugng phij hgp: Cong ty CP Tu v i n Thiit k l Xay dung CIDECO
2 D i i u kien dat nen
Cdc bao cao v l khao sdt dja c h i t e6ng trinh vd dja c h i t thuy van eho e6ng trinh g I m cd:
- Bdo cao khao sat dja c h i t c6ng trinh Cdng ty TNHH T u v i n Xay dung Nam Thien lap thang nam 2002 cd 16 khoan sau 45m va 50m;
- Bdo cdo dja c h i t cdng trinh Trung tam C l u dudng phia nam lap thdng 02 ndm 2006 vdi Id khoan sau 80m;
- Bdo eao khao sat dia chat c6ng trinh Trung tam Nghien cdu cong nghe va Thiet bj cong nghiep trudng Dai hgc Bdch khoa p h i H6 Chi Minh lap thdng nam 2009 kiem tra "o bun" vd mach nude n g l m cung nhu hieu qua c h i n g t h i m tai nhijmg c h i n l i gida cac t i m tudng sau bom phut xi mang gdm 15 Id, sau 25m/ld;
- Bdo cdo ciJa Lien hiep Dja ky thuat n i n mdng edng trinh lap thang nam 2009 phuc vu kiem djnh c h i t lugng he ket cau cdc tang ham g I m 16 vdi sau 80m/l6
(2)- Ldp 1: D l t san l i p co ehilu day m;
- Ldp 2: Set pha, xam nhat nau vang, trang thai deo m I m B l day Idp 4,2m;
- Ldp 3: Set pha san, xam t r l n g xam vang, xdm xanh, trang thai deo edng Chiiu day Idp 4,1m;
- Ldp 4: Cat hat nho d i n hat trung, nau nhat, nau vang, xam trlng, nau do, trang thai chat vua d i n chat Chiiu day Idp 29m;
- Ldp 5: Set nau do, vang nhat, trang thai cdng d i n rIt edng Chiiu day Idp 15,1m;
- Ldp 6: Set pha mau vang, xam xanh, xdm t r l n g , "trang thai nda cdng C h i i u day Idp 2,3m;
- - Ldp 7: Cat hat trung, nau vang, xam xanh, trang thdi chat d i n rIt chat Chiiu day d i n h i t h i khoan (- 80,45m)
Muc nude n g l m khu vuc la -9m td c6t eao mat d l t tu nhien, tuong d i i on djnh Cae chi tieu ea ly cua eac Idp d l t eho d bang 1, mat eat dja chat c6ng trinh xem hlnh
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Nhu vay, chan eua tudng vay vda vao mai Idp set ( s i 6) eon mui cua cgc barette vao mai ciia Idp eat pha ( s i 8)
3 Diln biin su c6
Do kh6ng co he quan t r i e de theo doi d i l n biin (Igc vd chuyen vi/biln dang) ciJa he k i t c l u ching giOf h i dao va c6ng trinh chung quanh nen nhdng th6ng tin sau day chii y i u thu thap tdcae phucrng tien truyen th6ng va ngudi chdng k i l n luc xay sU e l
- Thang 5-2007, c6ng trinh b i t d i u thi c6ng san t i n g ham, d i n thdng 10-2007 thi e6ng dugc b6n ting h i m va b i t d i u thi c6ng t i n g h i m thd Trudc xay s u ed da thi edng xong cdc panel tudng vay coc barrette va thi cdng be tdng d i n san t i n g tret tai cdc true -3 va 6-8 P h l n khoang hd td true d i n true sddung cac thep 1400 de Idm he ching dd tudng vay
- Ngay 9/10/2007, khoang 18 gid 30 dang dao d l t de chuan bj dd be tdng mdng thi d vj tri tiep giap tudng vay tai cao trinh -21m so vdi cdt nen tang tret ciia c6ng trinh Pacific, tudng vay x u l t hien 16 thiing rgng 30-35 cm, ddi 168 cm Do dp lue manh cua nudc
Hinh Mat cat dia chit cdng trinh dUdi nen cao dc Pacific
Hlnh S.Hien trang tang ngam Pacific (a) va toa nha Vien Khoa hoc Xa hdi viing Nam bd (b) sau sU cd 9/10/2007
Chi tieu ca ly cua cac Idp dat dugc trinh bay tom tat bang sau:
Li}p dat Chi tieu
Hat sdi % Hat cat % Hatbyi% Hat sdt % DO^mti/nhienW% Dung tn)ngti/nhien 7„T/m^ Dung trgng khflynT/m' Dung day noi Y,,„ T/m^ Ty AT/m^
Do bao hoa G% OQ rflng n% H^ s6 rong ^ Gidi han chay WL% Gidi han deo Wp % Chi so deo Id Og s?t B
Gdc ma sit <p° Luc dinh C KG/cm^
SPT -55,7 25,0 19,3 18,59 1,96 1,65 1,04 2,70 79 39 0,636 23,7 12,8 11,0 0,53 11°38' 0,132 7-9 -56,9 19,1 24,0 21,20 1,99 1,64 1,03 2,71 88 39 0,652 30,7 16,0 14,7 0,35 12°05' 0,242 16-20 29,0 32,0 17,0 22,0 18,19 2,01 1,70 1,09 2,77 80 39 0,626 30,7 15,7 15,0 0,17 13°17' 0,253 11-14 -57,2 20,6 22,2 18,65 2,03 1,71 1,08 2,71 86 37 0,585 27,3 14,6 12,7 0,32 13°04' 0,244 10-12 5a 10,1 44,4 27,5 18,0 14,67 1,93 1,68 1,06 2,70 65 38 0,607 22,0 11,8 10,2 0,28 15"13' 0,187 22 9,1 80,0 5,8 5,1 17,55 2,02 1,72 1,08 2,67 85 36 0,553 -24"'28' 0,055 12-31 -45,2 22,7 32,1 17,80 2,06 1,75 1,11 2,72 87 36 0,556 38,7 19,8 18,8 -0,11 16°35' 0,380 46->50 -61,0 16,2 22,8 17,26 2,04 1,74 1,10 2,71 84 36 0,557 31,9 17,1 14,7 0,01 14M5' 0,307 35->50 4,3 84,3 6,2 5,2 17,03 2,01 1,72 1,08 2,67 82 36 0,553 -16°04' 0,055 29->50
(3)BAI HOC TUf SI/ CO SAP BO VIEN KHOA HOC XA HOI
ngam tai vj tri 16 thiing nen gay tran nude va 161 d l t phia ngoai tudng vao t i n g n g l m (hlnh 3a) do khoang 19 gid thi day nha tru sd Vien Khoa hoc Xa hoi vung Nam bg g I m tret l l u b i t ngd sap, bj viii sau dudi long d l t hon 10m; p h l n lai ciia khu nha cung CO nguy ea sap (hinh 3b)
- Luc 17gid 23 thang nam 2008, hon thang sau su e l sap toa nha Vien Khoa hoe Xa hoi vung Nam bg, khu vuc de xe eiia Sd Ngoai vu tai s6 Alexandre de Rode, quan , d l u lung vdi cao l e Pacific, sut liin mgt 16 rgng 10m^sau 3m lam xe g i n may roi xu6ng h i (hinh 4a) va ndt tudng d khu ve sinh (hlnh 4b)
Hinh Hien trang nen tai nha de xe (a) va nUt tUdng khu ve sinh (b) ciia Sd Ngoai vu sau sued 23 /I /2008
4 Dieu tra s u co
Diiu tra dinh tfnh: Dua vao tai lieu thu thap duge td chinh quyen dia phuong vd ea quan quan ly thi trudc xay su e l da x u l t hien nhiiu d i u hieu canh bao su kh6ng binh thudng ciia nhung e6ng trinh lien ke nhu la:
- Sau c6ng trinh eao 6e Pacific thi cdng dugc mot thdi gian thi thang 11/2006 Vien KHXH co c6ng van giri cdc caquan chdc nang TP.HCM khilu nai don vj thi e6ng cong trinh cao l e Pacific kh6ng dam bao an toan, lam nut tudng vd co nguy ea lam sap Vien KHXH Cae don vj quan ly trat tu dd thj phudng, quan khao sat, lap bien ban vi pham va bdo cdo vu viec len CO quan quan ly nha nudc co tham q u y i n
Ngay 7/12/2006, Thanh tra Sd Xay dung TPHCM da CO Quyit djnh s6 112/SXD dinh ehi thi e6ng p h l n mong c6ng trinh eao l e Pacific t i i p gidp vdi Vien KHXH cho den thuc hien cac yeu e l u ciia Thanh tra Sd Xay dung vdi ly c6ng trinh vi pham trat tu an toan xay dung gay ran ndt va chan dgng tru sd Vien KHXH Thanh tra Sd Xay dung TPHCM yeu e l u chii d i u tu e6ng trinh Id C6ng ty TNHH Thai Binh duang va nha t h i u ngung thi e6ng p h l n mdng cong trinh, khac phuc su e l ; di ddi ngudi va tai san ciia Vien KHXH neu co nguy ca xay su c6 Ngoai ra, Thanh tra Sd Xay dung TP.HCM cung yeu elu phia chii d i u tueong trinh phai thue dan vj t u v i n giam sat; kh6ng the vda la chii d i u tu vUa la tu v i n giam sat
Ngay 4/1/2007, Sd Xay dung TPHCM da quyit djnh xu phat vi pham hanh chinh vdi mdc phat 29 trieu ding d i i vdi dan vi quan ly c6ng trinh cao l e Pacific la C6ng ty TNHH xay dung mot vien Thai Binh duang Ngay 4/6/2007, C6ng ty TNHH mot vien xay dung Thai Binh Duang va phia Vien KHXH da
thoa thuan dugc viec khac phuc su co c6ng trinh eao l e Pacific gay va hai ben tien hanh ky bien ban nghiem thu cae hang muc sda ehua, tram tret cac v l t ndt tai cac phdng lam viec ciia Vien KHXH
- Chi nda thang sau, 18/6/2007, phia Vien KHXH lai CO c6ng van giri den cac ea quan quan ly nha nudc TP.HCM tiep tuc "keu cuu" viee thi cong cong trinh eao 6e Pacific tiep tuc gay sat ndt va eo nguy ea gay sap tru sd Vien Qua khao sat, ghi nhan hien trang vu viee eiia ca quan quan ly trat tu thi thi mdc lan nghiem trgng hon lan trudc Ngoai eac vet ndt eij da dugc x d ly, tram tret tam bg, lai xult hien nhieu vet nut khac Nhung mdc xd ly l l n chi ddng lai d d p quan 17/7/2007 UBND Q.I quyet djnh xd phat vi pham hanh chinh xay dung d i i vdi Cdng ty Thai Binh Duang vdi mdc phat trieu d6ng va buoc dan vj phai khle phuc hau qua
- Ngay 9/10/2007, s u c i xay nhu da neu, lam hai day nha tru sd Vien Khoa hgc Xa hoi b i t ngd sap, tai lieu luu trdva may tinh bi viji sau dudi d l t hon 10m; p h l n edn lai ciia khu nha cung ed nguy ca sap
- Sau e6ng trinh tam ngdng va sd dung bien phdp ch6ng tham tai cae moi n l i gida cae t i m tudng tang ham C6ng ty 06ng Minh (Trung QuIe) thi c6ng bang khoan phut tao hang cgc xi mang dat CO dudng kinh d = 40 em 17h ehilu 23/1, han thdng tinh td toa nha Vien Khoa hgc Xa hoi phia Nam bj sap, Sd Ngoai vu k l ben c6ng trinh t i i p tue bj sut nen Nguyen nhan vu sut lun dugc xac dinh la anh hudng eiia viec bam nude ho dao xay dung toa nha eao 6e Pacific
Qua cdc tai lieu vda neu ehi cho b i l t tinh trang cdng trinh ve mat dinh tinh (nut va nguy hiem) ehua ehi ro s6 lugng vet ndt, be rgng va b l sau v l t ndt cung nhu su phdt trien cua ehiing theo thdi gian, so vdi bien dang cho phep de phan cap nguy hiem va td de cdeh x d ly thich hgp
Diiu tra djnh Iwang: Sau xay su e l , theo yeu e l u eua ea quan quan ly va chii d i u tu cung nhu caquan d i i u tra, da t i i n hanh dao, ehup anh, kiem tra chat lugng be tong b i n g sieu am, chuyen vj va bien dang mot s6 c6ng trinh lien ke, vd eho b i l t mot s6 ket qua nhu sau:
- Tudng vay bj thiing, ndt td vai cm d i n 20-30cm, d tang ham thd va 16 e l t thep chju luc td vai cm den 20, 27, 80 em, chan tudng bj nghieng nen phat sinh khe hdch6 tiep gidp/mli n l i (xem hlnh 5)
.' (a)
(4)- Cudng trung binh ciia be t6ng tugng vay kiem tra bing sieu am R^ « 264kg/cm2, thip hon mac thiit k l , edn theo kit qua thd mlu be tdng tuai trudc vao hao tudng Trung tam Clu dudng phia Nam thuc hien thi Rtb =453kg/em2, dat yeu elu thiit k l
- Theo kit qua va theo doi cua C6ng ty Kiem djnh Xay dung Sai gon din gida thdng nam 2008 thi mong nha xe va nha sach eiia Sd Ngoai vu lun 30-40mm so vdi cae thang trudc, ed chd tic d6 lun din 2mm/thang, gaeh lat nin bong rgp tren dien rgng, cda ra vao kho dong md Cao l e Yoco eiia toa bdo Tuoi tre ehua CO diu hieu hu hong
5 Xu- ly tam thdi
NhIm han ehi su phat trien eiia su e l , edng trinh tam ngdng mot thdi gian luc chd tim nguyen nhan, ehii diu tu da ky hgp ddng vdi Cdng ty Ddng Minh (TQ) thi c6ng khoan phut xi mang va tao hang ege xi mang dlt cd dudng kinh 40em de ching thIm dge cac vj tri tiip giap gida cae tim panel tudng vay Nhd lugng nude ngam chay vao ting nglm da giam di rd ret Cung chi'nh C6ng ty da thuc hien bam cdt va xi mang vao eh6 sut lun nen nha Sd Ngoai vu de han che sup day chuyen cd the xay sau su e l 23 thang nam 2008
6 Nguyen nhan sir cd
De tim nguyen nhan gay suel, nhlt la cac s u e l
phde tap, thudng xem xet cdc v i n d l sau day:
a Kiem tra thiit ki ting ngim
Sa d l kit elu ting nglm nhu mieu ta d muc 1, phln "Nin mong edng trinh" tren day
Sa d l tinh theo cac giai doan thi e6ng nhu hlnh va viec tinh toan theo h i sa thiit k l (vl kh6rig cd h i so hoan edng ) duge thuc hien bing phln mIm PLAXIS vgi eac thdng s6 dlt nin dung tinh todn cho d bang
Kit qua tinh todn ngi luc (M,Q) va chuyen vj (U^) duge dugc trinh bay tren cae hinh va hlnh
•0.00 r c M J'>^^ fjf ^^^JS!!?
Hinh Bien dang tdng ciia cdng trinh tai giai doan thi cdng tang ham cudi Ua, = 0.6m
Hinh Sd dd tinh loan tang ngam cdng trinh Pacific
Bang Cdc th6ng s i dung tinh toan
M ^ = 241Tm/m Lac cat Q„„,= 108T/m Chuyln vi ngang U „ „ - 0,2m
Hinh IVIdmen, lUc cit va chuyen vi ngang Idn nhit ciia tudng ting
ham
Project description: User name : Project name
Output
iD
1
Name
Lopi LDp2
3
Lop3 Lop4 Lop5 Lop6 i Lop7
Type
Drained Drained Drained Drained Drained Drained Drained
PUOflS- Finite Element Code for Soil and Rock Analyses Hodao Pacific
ins for Building Science and Technology Hodao Pacific
Soli and intertaces info - Hardening Soli
Yunsat
[kN/m'] 15,7 16,1 16,8 16,1 16,7 16,1 17,4
7ssl
[kN/m^l
19,0 19,5 19,4 18,9 19,9 19,1 20,0
K
[m/day] 0,0049 2.0300E4 2.920GE-3 0,1020 4.6100E-4 0,0042 3.0800
[m/day] 0,0049 2.0300E-4 2.9200E-3 J 0,1020 4.8100E-4 0,0042 3.0800
F '=* [kN/m^] 1877,0 1788,0 2889,0 6809,0 2022,0 2000,0 8248,0
teed
[kN/m^ 1877,0 1768,0 2689,0 6809,0 2022,0 2000,0 6248,0
PLAXIS 8.x
Date: 10/12/2009 Step: 18 Papal
c rrf '-ur
[kN/m^j 5631,0 5304,0 8067,0 20427,0 6066,0 8000,0 18744,0
[kN/m^ 17,5 37,2 12,5
4,4
55,6 17,3
5,2
•Pi*]
7,4
10,4 19,5 31,0 19,4 19,4 32,3
(5)BAI HOC TUf SI/ CO SAP 0 VIEN KHOA HOC XA HOI
Kit luan sabo
- M6 men tudng Idn n h l t ed gia trj 241 t i n - m nho hon gid trj 318,67 t I n - m dung de tfnh todn thep cho tudng vay thuylt minh tinh toan k i t c l u Cong ty T u v i n Xay dung dan dung Viet nam VNCC lap thdng nam 2006
Sa bg tugng vay dii kha nang chju lue qua trinh thi e6ng
-Tong chuyen vi eiia tudng U=0,6m (tdc Idn cua vecta chuyen vj) ehua xay dung cdc t i n g phia tren nen lun lue rIt nhd, dd chuyen vj la d l t dudi day t i n g h i m bj trdi len bang c h i n g thIm giua cdc tam tudng ehi e l m den day tang h i m (-21m), d i i u se lam eho nudc d Idp cdt phun trao vao h i mdng va d l t quanh h i mdng bj lun sut x u I n g , CO the d l y cung la mot nhung nguyen nhan lam nin nha Vien Khoa hgc Xa va n i n Sd Ngoai vu bj sap
- Chuyen vj ngang ciia tudng 0,20 m Id qud Idn Theo kinh nghiem nude ngoai (Han J, 1977) k i t e l u tudng c h i n chuyen vj ngang qua 30mm hoac 0,2%H (H la sau h i mdng) thi cdng trinh d each h i mdng 5m se bj huhdng nghiem trgng hoac rIt nghiem trgng Han nda, theo k i t qua quan trae cdc edng trinh h i mong sau d Bangkok chuyen vj ngang Idn n h l t eiia tudng d i n 100mm h i mong sau tren 20m (Phien-wej,N.2003)
Tong hgp loai chuyen vj vda neu duge the hien tren hlnh
Ca e h i gay su e l h6 dao nugc ngam cd the minh hoa tren hlnh 10
1 ^ ^ D n
Hmh Sd dd md ta nguyen nhan gay sUcd cdng trinh lan can hd dao
1 Nguyen nhan lam dlt ring va gay chuyen vj; Dlt bj dao hoac chuyen vj the tich; Phan b l chuyen vj the tfeh; Chuyen vi lun ciia mat dlt; Chuyen vj cua ket cau va nghieng lech; Hu hong kit c§u;7.0§t djch ctiuyen vao h i mong; Day mong bj day troi/nang len
b Kiem tra chit luong thi cong
Qua khao sdt c h i t lugng thi c6ng tudng v l be tdng va v l kin kbit eiia cdc khe n l i giua cdc panen sau xay su e l t h I y r i n g :
- Tudng bj thiing va ndt d nhiiu c h i , chan tudng bj nghieng lech (xem hlnh 5) dd ndae n g l m cd dg chenh thu9 lue cao (khoang 13m) ldp d l t cat ( s i 5) se d l dang mang eat ehay tran vao h i mdng gay sup nhanh chdng nha Vien Khoa hgc Xa hoi viing Nam bo ndm l i i n k l va phia tren Idp cdt vda neu
Chay qua cho ti/cmg bi nirt, va
Chay tu d(M chaa nuac Chay duoi chan tuang
Hinh 10 Mdt sd kha nang tac ddng cua nUdc ngam vao hd dao Mdt sd ghi nhan lue xay s u e l cung nhu k i t qua khao sat (dao d l t ch6 nude trao va cdc vet ndt cung nhu do lech tao khe hd gida eac t i m tudng ) da chung td nguyen nhan chinh gay sup nha Vien Khoa hgc Xa hoi vung Nam bg cung nhu d nen nha Sd Ngoai vu la tac dgng eiia nude n g l m qua c h i nut, khe hd bdi thi cdng kem chat lugng ciia tudng vay Dieu cung duge khang djnh Cdng ty D6ng Minh bom phut xi mang eho t i i p gidp giua cac tam tugng thi lugng nugc phun trao vao h6 mdng giam han vl luc he s i t h I m ciia d l t da giam td 10-^em/s edn 10-^cm/s
7 Mot s bai hoc
Qua phan tich cdc mat ed lien quan d i n s u e l nhiing cdng trinh liin ke vdi cao de Pacific ed the rut mot sd bai hgc kinh nghiem sau day:
a Vi mat quan ly: kinh nghiem eua n h i i u nude (Washinton, My; Frankfurt, CHLB Ddc; Thugng Hai,Trung QuIe, ) ngudi ta bat budc cae du an cdng trinh n g l m (thiit k l va thi e6ng) ed sau tren 5m d i u phai qua ea quan quan ly xay dung nha nude tham djnh, neu dat yeu cau mdi dugc phep thi edng Muc dich ciia viec la de giam riii ro cho cdng trinh va dam bao an sinh eho egng ddng Cd le d ta ehua quy djnh chat che van de va san sang chuyen sang "chii d i u tuehju mgi trach nhiem" chang? Nha t h i u thi cdng t i n g n g l m phai la nha t h i u cd nang luc va kinh nghiem duge chgn qua canh tranh edng trinh hlnh nhu khdng thuc hien d i i u dd?
b Tai lieu khao sat dit nin phuc vu eho thiit k l
t i n g n g l m vdi cgc sau tdi 67m nhung chi cd mot 16 khoan sau SOm, r I t it thdng tin v l d i i u kien thuy van nen dgng thdi nudc n g l m khdng duge sang to, tddo cd