Hd ddo md thudng Id nguyen nhdn chfnh Idm hu hai cdng trinh liln k l do chuyen vj nin dit, ddc biet 1^ d khu vuc dd thj. Cdc chuyen vj nin dit do hd ddo md cd cd hai thdnh phin ngang[r]
(1)D I I N DAN KHOA HOC CdNGNGHi KINH NGHIEM Nlf^C NGOAI TRONG PHdNG TRANH SU CO
CONG TRINH Ol LAN CAN H DAO SAU TRONG 0 THI
PGS.TS NGUYtN BA KE
Hoi Cd hpc d i t vd Dja ky thuat c6ng trinh Vi#t Nam T6m t6t: Gi6i thieu kinh nghiem cua nu6c ngoai, dya tren ket qua quan trSc hon 530 cong trinh ho dao sou dat mem y§u, de xuat tri canh bdo va trj gidi hgn ve chuyen vj ngang cua tudng vd chuyen vj ddng cua dot lan can ho ddo, dung chung de kiem sodt vd phong ngua nhung hi/ hgi cd the xdy ro doi vdi cong trinh gan ho ddo
Tir kho6:Bien dgng ngang; bien dqng g6c; trj gi6i hgn; trj ofinh bdo
1 To'ng quan
Trong nhQng nam gin ddy ptidt trien vd hien dai hod thj d nudc ngodi vd nhit Id d nudc ta, khong ft cong trlnh Idn can hd ddo da bj su cd ndng nl, gay nhilu tdn thdt v l kinh t l vd xd hpi, vf du nhU: - d Ha Long, Quang Ninh, ngdi nhd ting dd nghieng vdo Trung tdm Thf nghiem Kiem djnh Xdy dung (Cdng ty Co phin Xdy dung Bach Dlng),1 ngudi chit, ddo mdng nhd ben canh;
- Vidn Khoa hpc xa hpi vung Nam Bp bj sdp vd nin nhd xe Sd Ngoai vu TP Hd Chf Minh bi sut cd lien quan din viec thi cong tdng hdm cao dc Pacific liln k l ;
- Sap, nOt 10 can nhd d dudng Hdm Nghi, TRHCM md Cao dc Saigon M&C da bi dinh chi thi cdng mpt thdi gian;
-T6a nhd cao 13 tdng, tren mdng cpc, d thdnh phd Thupng Hdi sap hd mdng ben canh bj trupt vl ngap nudc mua; vd
Co chi cua hien tupng thudng gap ndy dupc trinh bay tren hinh
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Hinh Anh hUdng ho dio den cdng trinh 1 Nguyen nhan gay chuyen vi
2 Bat bi dao hoic dich chuyen 3 Phan bd chuyen vi the tfch 4 Chuyen vi mit dit
5 Chuyen vj ket cau vi si/huhdng (nClt,nghieng)
7 Chuyen vi dat quanh hd dio phia khdng cd cong trinh hien hdu TQ tren hinh ndy ta thiy:
Khi lly di mpt lupng dit ndo dd se Idm thay ddi trang thai Qng suit - biln dang cua khdi dit quanh hd
ddo
Olt se djch chuyen v l phfa hd ddo, dp Idn ciJa chuyen vi phu thuoc vdo chit lupng cua he kit cdu chdng giQ, loai dit, khodng cdeh cGng nhu vj trf vd tdi trpng cua cdng trlnh Idn can;
Tong hpp cdc loai chuyen vj ndy se Idm mat ddt b Idn cdn hd ddo lun xudng;
N I U vijng dnh hudng ndy cd cdng trinh thi cdng trlnh se bj biln dang
Nguyen nhdn gdy ehuyin vj vQa neu thudng phu thude vdo nhilu y l u td, nhu Id:
+ Tdc dpng cua su thay ddi Qng suit nin; + Kfch thude cua hd ddo;
+ Su tilp can (gin /xa vd song song hay vu6ng gdc) cua cdng trinh vdi hd ddo;
+ Cdc ddc tfnh cua dit;
+ LJfng suit nim ngang ban ddu ddt; + Tmh trang nudc ngim vd ddng thdi ciJa chiing; + Dd cQng cua tudng vdy vd hd chdng glQ (thanh chdng hoac neo);
+ Trlnh dd thi cdng;
+ Cdc nguyen nhdn chua bilt khdc
Nhu vdy cd rit nhilu nguydn nhdn dnh hudng tdi ehuyin vj cua kit d u vd vung dit xung quanh h i ddo cd vd khdng cd cdng trlnh Idn cdn Do tfnh bOc xuc cua vdn d l vQa neu len hien cd nhilu nghien cQu ting kit kinh nghiem thilt k l vd thi cdng cdng trlnh hd ddo dilu kien dd thj cd mdt dp xdy dung cao
Trong bdi bdo ndy se trlnh bdy nhQng kinh nghidm thuc t l cua nudc ngodi dua trdn sd lieu quan trie tCr hon 530 hd ddo ddt mim y l u vd phdn Qng cua cdng trlnh Idn can hd ddo cung edch ddnh gid vd phdng trdnh thong qua thilt k l yd thi cdng
2 Blln dang cua tudng chin yd dat gdn ho ddo
2.1 Nhin dang chuyen vl, blin dang
Christian Moormann (2004) da tdng kit trdn 530 su cd hd ddo ddt y l u trdn t h i gidi vd dua nhQng khuyin edo rdt quan trpng d l han c b l vd phdng ngQa sued O l tilp cdn vdn d l vQa ndu xin tdm t i t nhOng kit qud quan trpng tQ cdng trinh nghidn cQu ndy
Trudc tien Idm quen vdi mdt sd djnh nghTa vd cung chfnh Id cdc tidu chf chfnh dung d l kilm sodt vd ddnh NGUdi XAY DUNG S THANG - 2011
(2)KINH NGHIEM NtftfC NGOAI TRONG P H N G TRANH Stf C6
gid hu hai cd su cd Trdn hinh trlnh bdy cdc dinh nghTa v l tieu chf ehuyin vj cua tudng chdn vd dit quanh hd ddo vdi cdc thdng sd cd lidn quan se dupc dung bdo edo ndy
pbiWng diJDg guza cac choqg ^ i k ' N
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Hinh Cac dinh nghia lien quan hd dao H: chieu sau hd dio [m];
t: chiiu sau tudng chin [m];
hf khoing cich glOa cie chdng/neo [m]; (/^fr ehuyin vi ngang ldn nhat cua tUdng [m]; uT'^chuyin vi ddng Idn nhit cOa mit dit [mj; N: sd tang/hing chdng/neo
Mdt sd ket ludn ddng chu y cua Christian Moormann (2004) Id ehuyin vi cua tudng vd dit quanh tudng thude vdo tfnh chit cua ddt vd loai kit clu tudng chin Trdn hinh trlnh bdy quan he giQa u""" vdi u"""h vd dd lun cua ddt canh hd ddo cdn tren hinh 4:2 (u™,) = f(H)
35 30 25 20 15 10 S 0
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TQ dd ta thdy:
Odi vdi hd mdng sdu ddt mim, dd lun Idn nhit cua mat ddt canh hd ddo phu thupc vdo chilu sdu hd ddo vd ndm pham vl u'""yH=0,1-10,1%, trung binh u'""yH = 1,1%
Ty sd giQa ehuyin vj dQng Idn nhdt vdi chuyen vj
z{uj™') [ml 30
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3 C6n.K)nA3autucto
10 20 66 saM ho dao H
Hinh Quan he giOa sau z Ung vdi u"'^ vi sau hd dao H trong dit s6t mem
ngang Idn nhit thay ddi tQ 0.5 din 1,0, cdn ddi vdi dit sdt mim tdi ldn (hinh 3a) Dp lun Idn nhit tai mat dit quanh hd mdng thudng gap khodng cdeh 0,5 H tQ mdp mdng dit chat (cdt vd sdt) cdn dit sdt mim thi khodng cdeh 2,0H (hinh 3b)
Chuyen vj ngang Idn nhit cua tudng chin u'""^ xuit hidn d dp sdu z = 0,5-1,0H (ehilm 67%) vd d ddu tudng z =0 (ehilm 21%)
Clough vd O'Rourke (1990) cho kit qud nghidn cQu vdi d i t cQng Id u'"VH=0,05~0,25% vd u'"'"yH=0~0,20%; vdi ddt sdt mim chuyen vj Idn nhit cd t h i dat tdi u'"VH=3,2%
NhOng kit qud thu vj khdc, chi tilt hon, cd the tim dpc Christian Moormann (2004)
2.2 Mgt sd tieu chf diing dinh gia hu hai/su cd cdng trinh lan can
Theo suphan loai cua Skempton vd MacDonal, hu hai cdng trinh dupc chia loai sau: hu hai kiln true, hu hai chQc ndng vd hu hai v l kit cdu
Huhai kien true: hu hai v l kiln true lien quan tdi hu hdng xuit hidn kit d u Vlt nQt tren tudng, sdn thupc dang hu hdng ndy Vlt nOt vupt qud 0,5mm b l rpng Idp trdt trdn tudng vd vupt qud 1,0mm b l rpng khdi xdy tudng dupc xem xdt Id dp Idn gidi ban
Huhai ChQc nang: hu hai chQc ndng lien quan tdi hu hdng chQc ndng kit clu Loai hu hdng bao gdm: ket cQa sd, cQa di, nghieng tudng, sdn, udn hoac gdy cdc dudng dng ga, nudc Hu hdng chQc nang khdng ydu d u sQa chQa kit clu d l trd lai cong nang ban ddu
Hu hai kit ciu: hu hai kit c l u dnh hudng tdi dn djnh cua kit clu, thudng lidn quan tdi v l t nQt, biln dang cua cdc d u kien CP bdn: dim, cot, khdp ndi, sQc chju tdi cua tudng
Tren hinh trlnh bdy cdc djnh nghTa nhQng biln dang chfnh cua cdng trinh nam pham vi dnh hudng cua hd ddo vd sau dd Id cdc cdng thQc xdc dinh Chung theo Cording et al.(2001)
Moorak Son (2003) ddn kit qud nghidn cQu cQa Cording et'al (2001) v l edch xdc lap mpt sd thdng sd biln dang cua cdng trlnh dung de ddnh gid su hu hai
(3)WMHIICHieHHlMC mOAl TRONG PHdNG T R A H H Stf c
4 dua tren tri b i l n dang trung binh quan trdc dupc tQ
cong trinh idn can hd ddo B i l n dang cua tudng dupc xdc djnh bdi dae theo phuong t h i n g dQng (v), theo phuong ngang (I), chuyen vj (Ay By Cy Dy A| B| C| D|) tai gdc (A, B, C, D) n h u trinh bay tren hinh
N h u v d y de cd sd lieu dung ddnh g i d tinh trang ky thudt ciia cdng trinh Idn can, hd ddo phdi tien hanh khao sat nhQng cong trinh l y trudc xdy dung cOng n h u thuc hien quan t r i e no can than theo chuong trinh xdc djnh sudt q u d trinh thi cdng hd ddo
TQ sd lieu dae, dung cdc tieu chf sau ddy de
NHIPfl) NHIPg) NHIP®
30.90 39.12 16.51
TD^
14.48 6.35 14.48 -
UQ, • • • •
5.92 A ^ TB ^^ I ^^
38.77 16.54 6.12 - \- f ^ , - ^ - •; • ^
Hinh Biin dang cua cong trinh lan can hd dio ddnh gia:
Do ddc trung binh (slope) S Id s u thay ddi dp ddc tai day nha tren c h i l u ddi L:
S=^^-^' (1)
0 nghieng (tilt) T Id gdc xoay cua tudng dupc tfnh theo cong thQc:
2H T = (C,-B,)
H (2)
B i l n dang g6c (angular distorsion) p Id b i l n dang cdt duoc tfnh theo cong thUc:
P = S - T (3) B i l n dang ngang tai dinh (lateral strain at top)
Eia,(T) Id s u thay ddi chuyen vj ngang tai dinh cong trinh tren toan c h i l u ddi L:
SiAT) = D,-C, (4) B i l n dang ngang tai ddy (lateral strain at base) eia,(F) Id SUthay ddi chuyen vi ngang tai ddy mdng tren todn c h i l u ddi L:
s.iF).^^ (5)
Burland (1995) sQ dung ty sd b i l n dang (A/L) de thay cho b i l n dang goc (P) nhdm ddnh gid s u h u hai cua cong trinh, A Id chenh lun tai d i l m edch L Chu y r i n g b i l n dang goc p se dupc dung de ddnh gid s u h u hai cua cong trinh hien hOu g i n hd ddo:
P = A/L - (6) NGUdi XAY DUNG S THANG 3-2011
_ SiJf dung cdc cdng thQc trdn ta tfnh todn cdc thdng sd biln dang cho cdng trinh thuc t l neu trdn hinh 5, ta dupc:
Cung c6 the du bdo ehuyin vj cua cdng trinh Idn Tai nhip 1:
Dp die trung binh ^ J ^ Z L z l ^ = 3,64x10"'; 6100
OA KA - 14,73-4,83
0 nghiSng T = = 1,62x10" 6100
Biln dang gdc p = (3,64-l,62)xl0"^ = 2,02x10"^ Biln dang ngang B^tl) = —^ '-—=2,65x10"'
6100 B i l n dang ngang e,^(F) = 8,92-4,83
6100 = 0,67x10"' cdn b i n g phdn tfch k i t c d u d e m ket edu nhd hiSn hQu qui ddi thdnh d i m c d d d cQng tuong duong tr§n n i n d d n hdi, tQ d d tfnh d d lun/vdng v d b i l n dang g6c theo cdng thQc (6) v d i mdt s d thay ddi nhd theo R.J.Finno et al.(2005) hoac theo ludn vdn dd s6 tr§n CP s d tdng k i t v d k i l m chQng hdng 100 cdng trinh h6 ddo c u a N.S.Nikiphorova (2006)
2.3 Phan Ung cua cdng trinh lin cin hd dio md
Hd ddo md thudng Id nguyen nhdn chfnh Idm hu hai cdng trinh liln k l chuyen vj nin dit, ddc biet 1^ d khu vuc dd thj Cdc chuyen vj nin dit hd ddo md cd cd hai thdnh phin ngang vd dQng dnh hudng din cdc phan Qng cua edng trinh Cdc phdn Qng ndy dircic nhilu nhd nghien cQu quan tdm gia tang yeu clu bdo ve cdng trinh tai khu vuc dd thi
Nhin chung, mdt kit c l u gdm nhilu thdnh phdn c6 dp cQng vd dp bin khdc nhau, mdt sd khuylt tdt ciJa kit clu nhu v l t nQt cd t h i cd trudc bj chuyen vj cua nin dit hd ddo gdy Cdc kit qud nghien cQu d§u dua tren sd lieu thuc t l da dupc quan trie vd ddnh g\&
Gdc lech vd ehuyin vj ngang nhu nhOng thong s6 chfnh d l ddnh gid su hu hai Mac du cd mdt sd cdeh khdc d l md td lun lech, nhung ly lua chon biln dang gdc Idm tidu chf vl: 1) Cdng trinh gdn h6 ddo thudng cd dd lun Idch Idn 2) Biln dang gdc dl ddng quan sdt thuc t l
Cording et al (1978) dd nghien cQu phdn Qng cdng trinh cdc ehuyin djch n i n dit Cdc quan sdt thuc nghiem hu hdng cdng trinh tai Washington D.C vS New York tuong Qng vdi mQc dp biln dang So d6, d^ng v l t nOt dupc quan trie tai kit c l u nhd gach canh hd ddo, tudng chju luc vudng gdc vdi hd ddo, c6 ba dang v l t nQt dupc quan sdt vd md td nhu sau:
- Cdc v l t nQt v d dOt gay tdp trung c h u y l u d g i n cQa s d Khi cdc v l t nQt chdo t i l p x u c vdi mat tudng chfnh, cdc mdnh vun c u a Idp trdt c d t h i xdy
- Cdc v l t nQt gdn t h i n g dQng x u i t hien g i n mdi n\\k, kdo ddi vd xuyen qua hdng gach, cdc v l t nQt ndy xudt hien c6 lien quan tdi s u vdng Idn cua k i t c l u Cdc v l t nQt tdp trung gdn tudng chfnh noi c d gdc Idch Idn nhdt
(4)KINH NGHIEM NtfdIC NGOAI TRONG PHONG TRANH SI/ CO
cao khodng 1,5~3,0m Vi trf vd hudng cua chung dupc cho Id bj dnh hudng cua chuyen vi ngang cua nen
Ngodi vlt nQt, dd nghidng thi dp lun them vd chuyen vi ngang cua cong trinh Idn cdn cung c6 the din din nhGmg biln dang khong cho phdp (Ng Bd Kl, 2006)
2.4 Dinh gia mUc dp hU hai cdng trinh
Boscardin vd Cording (1989) da nghien cQu sulien quan giQa hu hai cdng trinh dua trdn biln dang kdo tdi han vdi cdc thdng sd biln dang (biln dang gdc p vd biln dang ngang tdi han Sh) Trong nghien cQu hai ong da sQ dung dim tmh dinh dat tren hai gdi don gian va tdi trpng tap trung ddt d giQa nhjp de lien he vdi biln dang tdi lian (p, e^) Bleu dd ddnh gid hu hai dua tren ty s l giQa mo dun ddn hdi vd md dun trupt E/G=2,6 vd ty sd giQa chilu ddi vdi chilu cao ngdi nhd l_/H=1 Hinh dudi ddy ehl biln dang tdi han 0,0005, 0,00075, 0,0015 va 0,003 cho biln dang liu
Bang Phan loai mQc dp hu hai theo be rpng vet nQt cua cdng trinh canh hd ddo
i
2
1
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n b KIU NOHC H4 oto
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Nhe
Trung binh
Ndng
R^t n ^ g
IV161§ loai hu hai
Vet ran nUt
Vet nUt de dang sUa chUa qua trinh trang tri
Vgt nUt de dang lap day, c6 the ygu C2lu trang trf lai
Vet nUt yeu cau ck bo va phu lai
Thay the xi mSng cho gach Sijfa chUa phdi thay the tudng, dae biet Ici d vung cila s6' vJ cu'a di
SiJfa chffa Idn keo theo phSi xay lai dSm mit kha nang chju luc Ciia sd bj h6ng hodn toan
Be rgng vet nUt xjp xi (mm)
<0,1
<1 <5
5 - hoac nhieu vet nirt >3mm
15-25 va phu thuOc vao so lUdng vgt nUt >25 va phu thude vao s6 lUdng v6t nUt
Mile M thiet hai: (0): Khdng nh$n biet; (1):Rknhe;
2
8I{N 1))N0 GfiC II (XIO'")
(2): Nhe; (3)(4):Vifatdinianh; (5): Rit manh
p theo cong thufc (3) Eh theo cong thufc (4)
Hinh Bieu dd dinh gii hUhai cdng trinh theo bien dang gdc p vi
blin dang ngang E^
hai tQ khdng ddng k l tdi rit nghiem trpng Gid trj gidi ban ndy se cd mpt sd gid trj thay ddi vl kit clu co ty sd E/G vd UH thay ddi Idn
Phuong phdp cua Boscardin vQa neu hien dung khd rpng rdi de ddnh gid mOc dp thiet hai cua cong trinh ldn can hd ddo, tQdd se xdc djnh giai phap xQ ly thfeh hpp cho hd ddo hoac cong trinh, c6 kit hpp vdi nhau, d l dat dupc hieu qud kinh t l vd ky thudt mong dpi
Trong thuc t l chi quan trie dupc su hinh vd phdt then vlt nQt cua cdng trinh hien hQu thi dung kit qud nghien cQu cua Burland de ddnh gid trang thai ky thudt ciJa cdng trinh lan can hd ddo theo b l rpng vlt nQt vd chQc ndng sQdung theo mQc dp hu hai (bang 1) Trong nhQng nghien cQu sau do, Storer J.Boone (1996) da tdng hpp y l u td : b l rpng v l t nQt, dp lun
hi/hai Khflng dang ke (0) Ritnh?(1)
Nhe (2)
Trung binh (3)
N?ng (4)
Rk nang (5)
B a n g P h d n d p h u hai c d n g trinh theo b i l n d a n g
Mo ta sir hi/ hai
Dau nUt n6 mflng
NiJt manh, de xijf II trang tri binh thUdng Trong nha c6 the cd lap nhQng cho nUt gay nh? Nhiing nUt ng d bgn ngoai ciJa cdng trinh xay bing gach c6 the nhSn thay nhin ki
NhUng ngt ng cfl th^ de dang tram Yeu cau phai trang tri lai Trong toa nha cfl mot so cho nUt gay Nhflng nUt ne cfl the kha Idn Ygu ciu trat Vila lai de chong thim Cijfa va cijfa so' cfl the bi ket nhe NhUng nUt ng cfl the ygu ciu dap va va lai Dinh ki lam Idp vUa trat de che giiu nhUng nUt ng Trat lai bgn ngoai cua cong trinh xay bing ggch va cfl le mdt s6 ch6 nho ciia cdng trinh xay bing gach phai siKa chUa lai Cfla va cfla s6 cfl th^ bl ket Hg thong dUdng 6ng cfl th^ bj dflt giy Tinh ch6ng thim thudng bi suy yeu
Nfll Chung vigc sifa chfla gom ca pha va xay lai mot phan tudng, dae bigt ca phin cfla va cfla s6 Khung cfla va cfla so bi udn, san tang bj doc rit dang k l TUdng b| nghigng hoac phinh rit dang k l Kha nang chiu lUc cua dim bj kgm di Hg th6ng ve sinh bi pha vd ygu ciu chinh vg sfla chfla bao g6m ca cue bfl hoac xay 1^1 hoan toan Dim mit kha nang chiu liie; tudng nghigng xiu va ygu ciu eh6ng dd Cfla sd' bi giy u6n Tin higu bdo nguy mat d'n dinh
B^ r6ng khe null
0,1mm
1mm
5mm
5 - 15mm hoac mot s6 khe nUt > 3mm
15 - 25mm, phu thuoc vao so lUdng ciia khe nflt
ThUdng > 25 mm, phu thuge vao s6 lugng cua khe nfll
Lun lech A
< 3cm (1,2 in) 3-4em (1,2-1,5in)
4 - c m (1,5-2.0 in)
5-8cm (2,0 - 3,0 in)
8-13cm (30 - 5,0 in)
> 13cm (> 5in)
Bien dang goc
P = ' A / L
< 1/300
1/300 -1/240
1/240 -1/175
1/175-1/120
V^20•^f70
>1/70
(5)MNH NGHIEM NtftfC NBOAI TRONG P H N G TRANH Stf C6
lech (chenh lun/lun khong ddu) vd b i l n dang gdc P(=A/L) de phan chia mQc dp hu hai cdng trinh Idn can h i dao nhu trinh bay d bang
Nhu vay dua tren k i t qua khao sat vd quan t r i e hd dao va cong trinh ldn can hd ddo ta x i p loai cdc hu hai theo hinh hoac theo bang ( n l u chi dupe v l t nOt) hay theo bang ( n l u co ddy du cdc thong sd), tQ se dua cac bien phap (thilt k l vd thi cong) n h i m quan ly rui ro xay dung cong trinh n g i m dd thj.^ Kiem soat riii ro/sir c d c o n g trinh lan can h d dao
De he k i t c l u chdng giQ hd dao cung ntiu eong trinh lan can no khong xay su ed phdi khdng c h i chuyen vj cua cong trinh hd dao thong qua tfnh toan va quan trie Nhiing due k i t neu d cudi muc 2.1, tQ hinh va hinh v l chuyen vj ngang u'^''^ cua tudng chin va chuyen vj dQng u'"^ cua mat d i t lan can hd dao dupc diing cho muc dfeh vQa neu tu vdn thilt k l d l xudt trj gidi han
Chu y r i n g d cac nudc phdt trien (Illinois, Washington D.C, My; Frantturk, OQc; Matscpva, Saint Peterburg, Nga, Thupng Hdi, Trung Q u d c ) ngudi ta d i u djnh cdc trj sd canh bao vd trj khdng e h l (qua tieu chuan thilt k l , thi cong hoac qudn ly) de kiem sodt rui ro thi cong hd ddo thj
Thudng dua theo d p cCia cong trinh hd ddo de xdc djnh tri khdng chd lun mat ddt vd chuyen djch ngang cua than tudng Khi khong cd qui dinh rieng thi diing cdc tieu chf bang de khdng c h i thilt k l vd gidm sdt hd dao d gdn cdc cong trinh cd t i m quan trpng d p va d p (theo DBJ-61-97)
Theo bang ta t i l n hanh kiem sodt su an todn (khong xay su cd) cua hd ddo nhu sau:
Bang Trj khdng e h l thilt k l va gidm sdt b i l n dang hd mdng cong trinh (theo DBJ-61 -97) Cip
cdng trlnh h6 dao
COng trinh
cipl Cdng trinh cip
Chuyen djch eiJa dinh tudng (cm)
Tri giam sat khing chi
6
Tri thiit
ki
5
10
Chuydn djch Idn nhit ciia than tudng (cm) Tri giam sat khing chi
8
Tri
thiit ki
8
12
LiJn ldn nhit d mat dit (cm)
Tri
giam sat khing chi
6
Tri
thiit ki
5
10
(1) Trong thilt k l , theo t i m quan trpng ciia cdng trinh, tu vdn thilt k l chi djnh trj chuyen vj, gpi Id trj thilt k l , cua h i ddo vd cua mat d i t ldn cdn hd ddo, xem chung la trj gidi han, quan trie luc thi cong xem day la ngudng nguy hiem;
(2) De an todn, c6n c6 trj khdng c h i , xem chung Id ngudng canh bdo; n l u sd lieu quan trie thi cdng dat ngudng ndy thi cdn tang g i p doi t i n s u i t quan
trdc de phdt hien xu hudng phdt trien cdc chuyen djch CLia hd ddo cung nhu cdc b i l n dang cua cdng trinh ldn can (theo hinh 6, bdng 1/bdng 2);
(3) N l u chuyen dich vd b i l n dang ndi tren qud mOc vd CO khd ndng g i n vdi tri gidi ban thi nhd t h i u lap tuc dimg mpi boat dpng xdy l i p vd thdng bdo cho ctiu d i u tu, trien khai bien phdp phdng ngira Chi sd lieu dat dn djnh mdi t i l p tuc thi cdng hd ddo
Bang C i p an todn hd ddo (theo DBJ-61-97) cip an toan
Cipl
cip II
Hau qua pha hoai
Kit ciu ching gifl bi pha hoai, nin dit mit 6n (^nh hoac biin dang qua Idn lam cho cdng trinh xung quanh hi ddo hoac vigc thi cOng kit ciu ngim bi inh hudng nghifim trqng
Kit ciu ch6ng gifl bj pha hoai, nin dit mit 6n dinh hoac biin d«ing qua Idn lam cho cdng trlnh xung quanh h6 dao hoic vigc thi cOng kit ciu ngim bi inh hudng vfla phai
d p cdng trinh neu bdng Id theo su phdn d p cua DBJ-61 -97 vd cho d bang
Khi xdc djnh tieu chuan khdng e h l b i l n dang phii tfnh d i n hieu Qng thdi gian cua b i l n dang vd khdng c b l tdc dp b i l n ddi cua trj sd gidm sdt, cdng trinh edp ndn khdng e h l d mm ngdy, d p 3mm ngdy Khi tdc dp lun dot ngpt tang len hoac lien tuc d tdc dp nhanh thi phdi kjp thdi phdn tfch nguydn nhdn, cd bien phdp ddi phd.Q
Tai lieu tham khao
1 Boscardin M; Walker M (\99&)-Ground
Movement.Building Reponse and Protective Measures
ASCE.October 18-21
2 DBJ-61-97 -Shanghai Standard Code for Design of
Excavation Engineering (in Chinese)
3 Finno Richard J et al (2005)- Evaluating Damage
Potential in Building Affected by xcavations J of Geotechnical
and Geoenronmental Engineering,131 (10)
4 Moormann C (2004)- Analysis of Wall and Ground
Movements due to Deep Excavations in Soft Soil Based on A New Worldwide Database.So\\ and Foundations,Japanese Geotechnical
Society, Vol.44,No ,Feb
5 Moorak Son (2003)- The Reponse of Buildings to
Excavations-inducted Ground Movements Thesis of Ph.D
University of Illinois
6 Nguyin Bd K§ (2006)-X^y dung cdng trinh ngim
thi theo phuong phip dio md Nhd Xudt bdn Xdy dung Ha
Noi
7 Storer J Boone {\99S)-GroundMovement Related Building
Damage J of Geotechnical Engineering, November
8 HnKnct)opoBa H.C (2006)-/7e<;fopMat<uty sdanuu
e6nu3U zny6oKUx KomnoeaHoe u nodaeMHbix ebipadomoK
e ycnoeufix mecHou aopodcKou aacmpouKu u Memodbi
saaiumbi flMCcepraMMn na concKaHne yMSHOM creneHM
flOKTopa TexHMHecKMx HayK MocKsa, HklHOCn MM H M Tepee saHOB