Hoi nghi khoa hoc ki thudt md qudc ti 2010 Cong nghiep md tien tien vi su phdt triin bin virng ON DINH CUA CAC Dl/CTNG HAM DAT NONG GAN BE MAT DAT T H I C O N G B A N G P H l T O N G P H A P N G A M C[.]
Hoi Cong nghi nghiep khoa hoc md tien ki thudt tien md qudc vi su phdt triin ti bin 2010 virng ON DINH CUA CAC Dl/CTNG HAM DAT NONG GAN BE MAT DAT THI C O N G B A N G PHlTONG PHAP N G A M CO C H U Y D E N CAC BlT(JC T H I C O N G ThS.Tran Tuan Minh, KS Nguyen Van Tri T n r d n g D a i hoc M o - D i a chat H a N o i Tdm tat: Viec xdy dung cdc dudng ham tau dien ngam cd dien tich mat cat ngang ldn nhieu trudng hap can cd bien phap thi cdng thich hop Chia guong la mot bien phap thich hop de tdng tinh dn dinh cho ducmg ham cung nhu tdng tdc thi cdng cdc dudng ham Tuy nhien, hien viec tinh toan vd phdn tich cd chu y den cdc buoc thi cdng cdc dudng ham han che Bdi bdo gidi thieu viec phdn tich dn dinh cdc dudng tau dien ngam nam gan be mat ddt cd chit y den cdc budc thi cdng khai dao Dat van de f r H i e n giao t h o n g tai cac l a n ciia n u a c ta dang t r a nen het sue buc xiic, mat p h u a n g t i e n giao t h o n g tang nhanh t r o n g k h i t h i he t h o n g d u o n g xa da t r o nen qua tai, quy dat g i a n h cho giao t h o n g dang t r d nen han che M o t t r o n g n h u n g phuang an dugc cho la h u u h i e u nhat h i e n la viec sir d u n g k h o n g g i a n n g a m T r e n the g i d i , viec xay d u n g he t h d n g tau d i e n n g a m de v a n c h u y e n hanh k h a c h da d u g c cac nha quy hoach t i n h den tir lau t r o n g t h a i k y h i n h va phat t r i e n t h i T u y n h i e n , viec xay dung tau dien n g a m c i i n g mac phai n h u n g han che nhat d i n h n h u anh h u d n g den cdng t r i n h xay d u n g tren mat, he t h d n g k y thuat ciia cac c d n g t r i n h tren mat, n u d e n g a m Ngay v d i nhung tien bd ciia k h o a hgc k y thuat t h i viec l a m g i a m den m i i c thap nhat cac anh hudng ke tren da t r d nen d o n gian h o n rat n h i e u de d a m bao h i e u qua sir d u n g ciia he thong Da phan cac he t h d n g tau d i e n n g a m da duoc x a y d u n g tren the g i d i deu dugc dat d sau k h o n g l d n , n h u cac d u d n g tau dien n g a m d N g a t h u d n g n a m d sau tir - 60 m [ ] , a A n h tir 10 - m rat i t cd he t h d n g tau dien n g a m dat d v i t r i sau h a n Cac d u d n g tau dien ngam t h u d n g cd the d u g c t h i cdng bang p h u o n g phap h d , hoac t h i cdng bang p h u o n g phap ngam K h i t h i cdng bang p h u o n g phap h d t h i tiet dien ciia c h i i n g t h u d n g la h i n h c h u nhat t h i cdng bang p h u o n g phap n g a m t h i h i n h dang ciia n d rat da dang t u y thudc vao dieu k i e n dat da cung n h u b i e n phap t h i cdng v a t i n h d n d i n h ciia cdng t r i n h T i e t dien cac d u d n g h a m tau d i e n n g a m rat da dang, t u y thudc vao k i c h t h u d c dau tau va l u u l u g n g v | n chuyen V d i dieu k i e n n a m gan be mat dat va tiet dien l d n c i i n g n h u d i e u k i e n dat da yeu nen viec t h i cdng toan tiet d i e n t h u d n g d i i n g cac may m d c thiet b i h i e n dai T r o n g nhieu t r u d n g hop d u d n g h a m buoc phai t h i cdng bang b i e n phap chia g u o n g de tang t i e n khai dao va dam bao an toan t r o n g qua t r i n h k h a i dao cac d u d n g h a m H i e n viec tinh toan phan t i c h d n d i n h cho cac d u d n g tau d i e n n g a m n a m t r o n g l o n g dat cd chii y den cac bien phap k h a i dao bang toan hgc thudn t u y la rat k h d k h a n v a n h i e u t r u d n g hgp la khong giai quyet dugc, v d i l g i i c h ciia m i n h cac p h u o n g phap sd [ ] cang dugc u n g dung rong rai de phdn t i c h danh gia m i i c o n d i n h k h i k h a i dao cac d u d n g tau d i e n ngam, dac biet la t r o n g qua t r i n h phan t i c h , thiet ke d n d i n h , k h a i dao cac d u d n g h a m cd c h i i y den cac budc k h a i dao la d i e u can thiet B a i bao g i d i t h i e u viec phan t i c h d n d i n h cho cac dudng tau dien n g d m n a m n o n g gan be mat ddt cd c h i i y den t r i n h t u k h a i dao d u d n g ham 364 Hpi Cong nghi nghiep khoa hoc md tien kT thudt tien md quoc vi su phdt te - trien ben 2010 vitng D u o n g h a m t h i c o n g b a n g p h i r o n g p h a p c h i a g u o n g V i e c t h i c o n g cac d u o n g ham sir dung b i e n phap chia g u o n g t r o n g qua t r i n h khai dao da la x u h u o n g tat y l u t r o n g qua t r i n h t h i cong cac d u o n g h a m t r o n g n h u n g dieu k i e n dat da m e m y e u , t i l t d i e n d u o n g ham I o n , can day nhanh tien t h i cong, tang t i n h o n d i n h duong h d m va g i a m anh h u o n g den k h o i da x u n g q u a n h c u n g n h u m o t so y e u cau khac So cac bien phap chia g u o n g co the d u o c the h i e n n h u t r o p g H i n h V i e c lua chon so t h i cong chia g u o n g nao t h i p h u thuoc vao rat n h i e u yeu to n h u d i e u k i e n dat da, trang t h i l t b i , t i n h k i n h t l m a n g u o i thiet ke t h i cong co the l i n h hoat sir d u n g t r o n g bat k y truong hop nao i Hinh Vi du trinh tu thi cdng du dng ham tren mat cat ngang A Dao toan guong; B Dao vom tien truoc roi nen; C Noc tien truoc roi mo rong sang hai ben va nen nhieu ldn; D Dao Id dan hai ben, noc tien trudc vd vom nguoc; E Dudng hdm dan, khai dao tirng phdn; F ducmg hao dao theo tirng ben Buac Bu6c Buac Hinh Md hinh dudng hdm tiet dien ldn ddo chia guong 365 d ngoai thuc te [4] Hoi Cong nghi nghiep Hinh Vi du nipt dudng khoa hoc md tien ki thudt tien mo qudc vi su phdt ham thi cdng theo phuong triin ti - 2010 bin phap chia guong virng thuc te [4] Cac phuong phap phan tich on djnh duong ham H i e n co rat n h i e u p h u o n g phap phan t i c h , t i n h t o a n o n d i n h d u o n g ham Tuy nhien co the phan c h u n g l a m cac n h o m n h u sau [ ] : - N h o m p h u o n g p h a p g i a i t i n h d a i so: D a y la n h o m p h u o n g phap t i n h toan tren ca so ket qua c h i n h xac sir d u n g m o t so gia thiet t i n h toan, x a y d u n g m o h i n h va thong qua giai cac p h u o n g t r i n h dai so c h i n h xac de t i m ket qua can thiet T u y n h i e n , m o hinh chi phan t i c h d u o c cho n h u n g d u o n g h a m v o i tiet dien d o n g i a n b i e n t r o n hoac gan nhu tron, h i n h c h u nhat, c o n cac tiet dien mat cat ngang phuc tap t h i se t r d nen het sue phuc tap va kho giai quyet M o t d i e m nua cung can quan t a m la p h u o n g phap giai t i c h t h i chi ti'nh toan duoc cho toan b d d i e n t i c h da k h a i dao va cd ket cau c h d n g c o n viec phan t i c h dn djnh theo t r i n h t u cac b u d c k h a i dao n h u tren h i n h v a k h i chua cd ket cau chdng g i u qua t r i n h khai dao la rat han che - N h o m p h u o n g p h a p k i n h n g h i e m : D u o c xay d u n g tren c o sd phan tich, danh gia theo k i n h nghiem thiet ke cac d u d n g ham T i r viec quan sat, k i n h n g h i e m t h i cdng cac dudng ham kem theo viec quan sat su thay d d i dat da x u n g quanh bien h a m de dua cac phuong phap, ket cau chong giir thich hop tao su d n dinh cho d u d n g ham M a c d i i cd n h u n g nhuoc diem nhat dinh nhuong n h o m p h u o n g phap van duoc sir dung - N h o m p h i r o n g p h a p q u a n t r a c dac: N d i d u n g ciia n h o m p h u o n g phap la sir dung cac thiet b i dac quan trac t r o n g qua t r i n h x a y d u n g d u d n g ham, tir dd d u bao cac gia t r i bien dang d i c h chuyen va lira chon ket cau c h d n g g i u p h i i h o p T i e n bo ciia n h o m p h u o n g phap cd the ke den la p h u o n g phap dao h a m m d i cua A o , p h u o n g phap thiet ke ket cau c h d n g g i u tren c o sd d i e u c h i n h b i e n dang - N h o m p h i r o n g p h a p p h a n t i c h so: H i e n v d i su phat t r i e n ciia khoa hoc ky thuat, may t i n h v a cac thiet b i k y thuat t i n h toan hien dai d d i va phat t r i e n cho phep xay d u n g phan t i c h , t i n h toan m o t each t i e n l o i , nhanh chdng h o n cac ket qua phan t i c h so vdi cac p h u o n g phap d tren Cac p h u o n g phap so h i e n cd the ke den n h u la: N h o m cac p h u o n g phap phan t i c h so dua tren c o sd p h u a n g phap phan tir h i r u han, p h u o n g phap phan tir bien, p h u o n g phap sai phan h u u han, phdn tir r d i r a c m d h i n h phan t i c h ciia cac phuang phap sd cd the d u g c the h i e n n h u t r o n g so h i n h 366 Hoi Cong nghi nghiep khoa hoc kT thudt md tien tien md qudc vi sir phdt te - trien 2010 ben viing Cac p h u a n g phap so M o hinh lien M o hinh khong lien tuc tuc M o hinh tuong tac giua ket cau chong va dat da Phuang phap P h u a n g phap P h u a n g phap P h u a n g phap phan tir h u u phan tir bien phan tir r d i phan tir rac han P h u a n g phap sai phan h u u han Hinh Cdc phuang phap so dia ky thudt (theo Sinha.R.,S.,1989) [3] P h a n t i c h so cho d u o n g h a m co c h u y d e n b i e n p h a p c h i a g i r o n g b a n g Phase Phase la phan m e m p h u a n g phap sd dugc x a y d u n g tren ca sd nen tang p h u o n g phap phan tir hiru han [ ] , d u n g de phan t i c h , t i n h toan v a t h i l t ke cdng t r i n h ngam T i n h nang cua nd k h a da dang, ket qua t i n h toan v a phan t i c h da d u g c k i e m n g h i e m / T u y nhien, viec sir dung n d de phan t i c h d n d j n h cho cac d u d n g tau dien n g a m cd c h u y den chia guong t h i c o n rat han che D a u bai cua b a i toan dat n h u sau: G i a sir m o t d u d n g h a m tau dien ngam cd dang v d m ( n h u h i n h 1), tiet dien mat cdt ngang d u d n g k i n h D = 10m, dugc dao d d d sau m t r o n g dieu k i e n dat da d u g c cd cac dac t i n h c o l y n h u t r o n g bang va gia thiet be mat dat la bang phang, v i i n g bien n g h i e n ciru t i n h tir bien h a m x a vao long dat da la m Bdng Tham so ddu vao cho bdi toan phdn Thu- tu 1 T e n t h a m so d a u v a o K y hieu Gia t r i Don vi T r g n g l u g n g rieng Y 0,02 MN/m 0,01 MPa c 0,05 MPa cp E 25 Do 1000 MPa u 0,25 - W Do (Pre 26 Do D d ben keo T— L u c d i n h ket Gdc m a sat t r o n g ^ M d d u n dan h d i He sd poisson Gdc dan n d Gdc m a sat d u tich 367 J Hpi Cong 10 nghi khoa nghiep md hoc tien kT thudt tien md qudc vi su phdt , D o ben d i n h ket d u Duong kinh tuong te - trien 2010 ben vung Cre D 0,5 MPa 10 m duong duong ham 11 L o a i vat l i e u Deo (plastic) - - 12 T i e u chuan sir d u n g Mohr - Coulomb - - 13 T y so u n g suat nam G3/G1 0,75 - ngang/thang d u n g Tren co so l y thuyet dau vao n h u tren bang p h u o n g phap so co the lap d u o c mo hinh phan t i c h n h u t r o n g h i n h 6Buac SBOn iiiii»nii,.mmii)Wli Buac Hinh Thu tu khai dao dudng ham (hinh ben trai) vd kit qua md bang Phase thu nhd (hinh bin phdi) phong V i e c khai dao d u o n g h a m se duoc tien hanh cat theo tirng b u o c m o t cho dung voi thuc te khai dao d u o n g h a m thuc te ngoai hien t r u o n g V i e c m o p h o n g cac buoc khai dao co the x e m d u o c t r o n g h i n h Hinh Hinh Md phong Mb phong khai dao tir budc vd budc khai dao tir budc vd budc 368 Hdi Cong nghi nghiep khoa hoc md tien kT thudt tien md quoc vi sic phdt te - trien ben 2010 vung Hinh Ket qua viing phd huy khai dao tu bu&c va budc Hinh Ket qua vung phd huy khai dao budc vd bu dc Co the nhan thay rang k h i v u n g dat da b i pha v a k h a i dao c o n n h a t h i v u n g bien dang va anh h u d n g , cung n h u v i i n g sap dd x u n g quanh g u o n g dao n h d D i e n t i c h guong dao cang m d r d n g t h i v i i n g pha huy, b i e n dang x u n g quanh g u o n g dao cang tang, cac gia t r i d i c h chuyen, bien dang va u n g suat x u n g quanh bien h a m cung tang len t u o n g ung D o phdn u n g suat nguyen sinh t r o n g dat da la gan bdng t y so ciia nd 0,75 nen viing phan b d b i e n dang deo va v i i n g pha huy gan n h u d d i x u n g Qua phan t i c h cung co the xac d i n h duoc gia t r i ap luc dat da v i i n g ddt da b i pha h u y va m o t phdn v i i n g b i l n dang ben ngoai v i i n g b i e n dang deo ddt da gay nen, va cung cd t h i k i l m tra, d d i c h i m g lai v d i cac gia thiet t i n h toan ap luc d l t i n h toan phan t i c h k i t cau c h d n g d n h u n g budc t i l p theo Ket luan va kien nghi Cd the thay rang viec k h a i dao d u d n g h a m sir d u n g bien phap t h i cdng la h u u hieu va can thiet de khai dao cac h u d n g h a m tau dien n g a m cd t i l t dien l d n k h i may mdc t h i l t b i khai dao toan t i l t d i e n c o n han c h i H a n c h i ciia cac bai toan dai sd giai t i c h cho d i n day da duoc giai q u y l t Q u a vi?c phan t i c h sd d tren cho chung ta thay viec k i l m c h i m g l a i cac gia t h i l t t i n h toan ap lire dat da trudc day, su phan b l v i i n g b i l n dang, cd c h u y duoc d i n tirng giai doan, tirng t h o i k y t h i cong nen co t h i dir doan s d m duoc cac kha nang cd t h i gay 369 Hoi Cong nghi nghiep khoa hoc md tien ki thudt tien md qudc vi su phdt te - trien bin 2010 vung sap va phan tich, du doan ket cau chong thich hop N6u sir dung vong lap nhieu lan thi co xac d i n h dugc cac gia t r i c h i n h xac cua chieu day v o ch6ng, c u n g n h u xac d i n h dugc chinh xac quy luat b i e n d o i cua u n g suat b i e n dang de danh gia dp luc dat da sau k h a i dao Qua day c i i n g k i e n n g h i rang viec phan t i c h so co the sir d u n g t r o n g cac d i e u k i e n dia chat, dia h i n h rat da dang D a y co the la m o t p h u o n g phap m o h i n h so co the d u g c sir dung de phan t i c h o n d i n h v a k i e m c h i m g k h i H a N o i v a T h a n h H o C h i n h M i n h tien hanh khai dao cac d u o n g tau dien n g a m n a m n o n g co tiet dien I o n t r o n g cac m o i t r u o n g dat da khac T u y n h i e n , k h u y e n rang t r u a c k h i sir d u n g nen k i e m tra cac t h o n g so dau vao dia chat dau vao m o t each c h i n h xac m a i cho ket qua dau p h i i h o p v a c h i n h xac Tdi lieu tham khdo [ ] X a y d u n g tau d i e n n g a m , nha xuat ban M o s k v a n a m 1970 (ban tieng N g a ) [ ] N g u y S n Q u a n g P h i c h va nnk Sir d u n g phan m e m p h u a n g phap so tinh toan cong trinh n g a m va m o , D e tai cap Bo, H a N o i , 2007 [ ] T r a n T u a n M i n h , N g h i e n c u u cac qua t r i n h b i e n d o i c a hgc t r o n g k h o i dat da co chu y den cac t h a m so, l u a n v a n thac sy k y thuat, H a N o i , 2008 [ ] Photo i l l u s t r a t i o n to support the teaching o f topic o n tunnel construction, prepared b y R a y m o n d W o n g [ ] Desai.C.S ( ) , I n t r o d u c t i o n to the f i n i t e element m e t h o d , N e w Y o r k 370 ... b i , t i n h k i n h t l m a n g u o i thiet ke t h i cong co the l i n h hoat sir d u n g t r o n g bat k y truong hop nao i Hinh Vi du trinh tu thi cdng du dng ham tren mat cat ngang A Dao... xac sir d u n g m o t so gia thiet t i n h toan, x a y d u n g m o h i n h va thong qua giai cac p h u o n g t r i n h dai so c h i n h xac de t i m ket qua can thiet T u y n h i e n , m o hinh... vi su phdt te - trien bin 2010 vung sap va phan tich, du doan ket cau chong thich hop N6u sir dung vong lap nhieu lan thi co xac d i n h dugc cac gia t r i c h i n h xac cua chieu day v o ch6ng,