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Hdi nghi khoa hoc kT thudt md quoc te 2010 Cong nghiep md tien tiin vi su phdt trien ben vung N G H I E N C U T J A N H H l T C T N G C U A G O C D O C V i A D E N V U N G A P L U C T I T A T A I T R[.]
Hdi nghi Cong nghiep khoa hoc kT thudt md quoc te - 2010 md tien tiin vi su phdt trien ben vung N G H I E N CUTJ A N H HlTCTNG C U A G O C D O C V i A D E N V U N G AP L U C TITA T A I T R U B A O V E C H O L O D O C V I A • S • • • • TS Dao Hong Quang V i e n K h o a hoc C o n g nghe M o - T K V TS R u d r a j i t M i t r a , G S Bruce H e b b l e w h i t e T r u o n g D a i hoc N e w South Wales, A u s t r a l i a K S Pham V a n Hoa C o n g t y T N H H M o t T V than N a m M a u - T K V Torn tat: Bdi bdo trinh bay ket qua nghien cuu su dnh hudng cua gdc ddc via den su phdn bd dp luc tua tqi tru bdo ve Id doc via khai thdc via than bang he thdng khai thdc cot ddi theo phuong, Id cho khau ldp tru, tran thu hdi than lap ndc Muc dich cua nghien ciru Id so sanh sir khdc biet ve sir phdn bo dp luc tua tqi tru bdo ve Id doc via khai thdc cdc via cd gdc ddc via khdc Kit qua cua nghien cuu se giup cdc nhd thiet ke md viec xac dinh chieu rong cua tru bdo ve, dam bdo Id doc via van tdi cua tdng tren cd the tri de lam Id doc via thdng gid cho tdng tiep theo qua trinh khai thdc Dat van de T r u bao ve g i u a 16 cho va 16 doc v i a dong v a i tro rat quan t r o n g t r o n g viec dam bao an toan va hieu qua k h a i thac T r u bao ve giua g u o n g 16 c h o va 16 doc v i a v a n tai duoc tao nham muc d i c h t r i o n d i n h 16 doc v i a v a n tai t r o n g suot t h o i gian t o n tai tir 16 doc via cua tang tren, sau la 16 doc v i a thong gio N g o a i ra, t r u bao ve cung duoc dung de each l y anh h u o n g cua g u o n g k h a i thac hien tai den g u o n g k h a i thac t r o n g t u o n g l a i , g i a m thieu nhung r u i ro ve nuoc, k h i Cac nghien c u u l y thuyet va thuc n g h i e m deu chi rang viec k h a i thac l a m thay d o i trang thai ap luc cua dat da va tao cac v u n g ap luc bao quanh k h u v u c k h a i thac N h u n g vung ap lire la ket qua true tiep cua su thay d o i trang thai u n g suat l i e n sat g u o n g k h a i thac K i n h n g h i e m thuc te cho thay 16 chuan b i neu duoc bo t r i t r o n g k h u v u c ap luc tua Ion nhat t h u o n g k e m o n d i n h h o n k h i nam k h u v u c khac D o cac d u o n g 16 chuan bi k h i thiet ke t h u o n g duoc bo t r i nam ngoai v i i n g anh h u o n g cua v u n g ap luc tua 16n nhat Rat nhieu nha khoa hoc tren the g i o i da nghien c u u su phan bo ap luc tua tai t r u bao ve 16 doc via van tai T u y n h i e n , n h u n g nghien ciru thiet ke chieu r o n g t r u bao ve truoc day chu yeu tap trung ap d u n g cho cac v i a bang Su anh h u o n g ciia goc doc v i a den su phan bo ap luc tua Ion nhat tai t r u bao ve chua duoc nghien ciru c h i tiet D o do, viec nghien c u u su anh huong cua goc doc v i a den su bien dong ciia ap luc tua tai t r u bao ve 16 doc v i a t r o n g qua trinh khai thac v i a day doc la rat can thiet nham ho t r o cho c o n g tac thiet ke Bai bao t r i n h bay ket qua nghien c u u su anh h u o n g cua goc doc v i a den su phan bo ap luc tua tai t r u bao ve 16 doc v i a tren co so ket qua phan t i c h tren m o h i n h so K e t qua nghien c u u se ho t r o cac nha thiet ke m o lap ke hoach, thiet ke chieu r o n g t r u bao ve 16 doc via, dam bao 16 chuan b i nam ngoai v i i n g ap luc tua I o n nhat, g i u p nang cao m u c o n dinh t h o i gian t o n t a i , g i a m thieu cong tac cung co, g i a m t y le t o n that than 357 Hpi nghi Cdng nghiep khoa hoc ki thudt md qudc ti - 2010 md tien tien vi sir phdt triin ben virng X a y d y n g m o h i n h so M o h i n h m o p h o n g dat da va qua t r i n h k h a i thac d u o c x a y d u n g bang phan m e m so F L A C hang Itasca ( M y ) [ ] san xuat phuc v u cho cong tac n g h i e n c u u m o B o n m o h i n h khac m o p h o n g cac via than co cac goc doc t u o n g u n g la 0°, 15°, ° v a ° M o i m o h i n h bieu dien g o m v i a than co chieu day 6,0m v a cac l o p dat da vach va tru v i a C h i e u cao k h a i thac ciia l o p t r u gia d i n h la 3,0m, l o p than Chain pillar Cross section modelled in FLAC analysis noc phia tren ( , m ) d u o c t h u h o i Gate roadway will be driven ciing v o i qua t r i n h k h a i thac L o c h o xay d u n g tren mo liinh h i n h so sir dung he t h o n g k h a i thac So" chi vi tri xdy dung md hinh sd sir dung phdn mem FLAC v o i 16 doc v i a t h o n g gio va 16 doc v i a van t a i V i t r i 16 c h o m o phong duoc xay d u n g tai k h u v u c pha hoa ma v i t r i do, dat da tai l u o n g pha hoa da sap hoan toan, va cac v u n g ap l u c x u n g quanh guong khai thac da t r o ve trang thai o n d i n h So v i t r i xay d u n g m o h i n h so hoa sir dung phan mem F L A C the h i e n tren h i n h B e m o p h o n g v i a than, da vach va da t r u t r o n g m o h i n h so, b o n loai vat lieu khac da duoc x a y d u n g L o a i vat lieu bien dang deo ( S t r a i n - S o f t e n i n g ) duoc dung de the hien v i a than n h a m the hien cac trang thai bien dang khac t r o n g qua t r i n h c h i u ap luc L o a i vat l i e u dan h o i deo t u y e n t i n h ( M o h r - C o u l o m b ) duoc d u n g de the h i e n dat da vach va t r u v i a than N h i r n g k h u v u c n a m xa h o n duoc the hien bang dan h o i deo (Elastic) Loai vat lieu bien dang dan h o i ( B o u b l e y i e l d ) duoc d u n g de the hien dat da pha hoa t r o n g v u n g sap do, n o i ma the t i c h g i a m k h i xuat hien ap luc nen B e m o h i n h m o p h o n g t u o n g t u n h u dieu k i e n dia chat k y thuat m o thuc te, cac gia tri c u o n g khang nen cua than va da t r o n g phong t h i n g h i e m duoc h i e u c h i n h theo huong giam k h i t i n h t h e m m u c nut ne t r o n g trang thai nguyen k h o i C u o n g khang nen cua than va dat da duoc h i e u c h i n h de dam bao cho buoc sap ban dau cua guong khai thac duoc gia d i n h se la 10-15 m K h o a n g each sap d u o c chon theo k i n h nghiem thuc te k h i k h a i thac cac 16 c h o tai cac m o than h a m 16 v i m g Q u a n g N i n h , V i e t N a m Mot so t i n h chat c o l y khac cua dat da n h u t r o n g l u o n g the t i c h , m o d u n dan h o i , goc n o i ma sat cua than va vach t r u v i a duoc lay n h u cac loai dat da co d i e u k i e n t u o n g t u v i i n g Quang N i n h B e so sanh, t i n h chat c o l y da, ap luc ban dau t r o n g m o h i n h so duoc giir nguyen k h o n g thay d o i v o i chieu sau k h a i thac t r u n g b i n h la 0 m A p luc thang d i i n g duoc xac d i n h theo cong thiic (1), ap luc ngang duoc thay d o i de phan t i c h m i i c anh h u o n g den vung ap luc tua 16n nhat o- = p.g.H (1) v 358 Hdi nghi Cong nghiep khoa hoc ki thudt mo quoc te - 2010 md tien tien vi sir phat trien ben vimg T r o n g do: o \ - A p lire thang d u n g ; H - C h i e u sau k h a i thac; p - T r o n g l u o n g the t i c h ciia than/da Qua trinh khai thac guong 16 cho duoc m o phong bang each xoa lan l u o t m chieu dai theo huong doc, chieu cao 3.0 m tai lop t r u cua v i a than theo h u o n g tir 16 doc via thong gio xuong 16 doc via van tai T o n g chieu dai tien guong cua 16 cho m o h i n h deu la 100m Qua t r i n h sap than l o p noc v a da vach duoc xay d u n g dua tren t i e u chuan m i i c yeu va v o cua loai vat l i e u dan h o i deo t u y e n t i n h ( M o h r - C o u l o m b ) , t u o n g tir n h u phuong phap sir d u n g t r o n g nghien ciru cua n h o m tac gia H e b b l e w h i t e va n n k [ ] Sau m o i buoc tien ciia g u o n g k h a i thac (2 m chieu dai), trang thai b i e n dang cua tat ca cac v u n g thuoc k h u vuc than l o p noc va l o p da vach phia tren g u o n g 16 c h o deu duoc k i e m tra Bat ky k h u vuc nao dat trang thai m o i hoac v o , no se d u o c x e m la sap do, va trang thai l i n g suat ciia v i a than va da vach, da t r u x u n g quanh k h u vuc k h a i thac se duoc phan bo lai den dat trang thai can bang L chuan b i duoc bo t r i phan than nguyen k h o i va n a m phia d u o i g u o n g khai thac, sau k h i 16 c h o k h a u het 100m va k h u vuc k h a i thac o trang thai u n g suat can bang M u c d i c h cua viec x a y d u n g 16 chuan b i t r o n g m o h i n h so str d u n g phan m e m F L A C la nham xac d i n h anh h u o n g cua 16 chuan b i den v u n g ap lire tua I o n nhat tai t r u bao ve dieu k i e n goc doc v i a khac L chuan b i duoc bo t r i b a m t r u v i a than va each g u o n g da khai thac lan l u o t la m , 10m, 15m va m v o i dieu k i e n goc doc: v i a nam ngang (0°) va via doc nghieng (30 ) C o n g tac chong g i u 16 chuan b i d u o c m o p h o n g dua tren cac cong cu ho t r o co t r o n g phan m e m F L A C P h a n t i c h d a n h gia k e t q u a m o h i n h so Hinh Dudng phdn bo dp luc tua tqi tru than phia tren Id chp cdc dieu kien gdc doc via 359 Hpi nghi Cong nghiep khoa hoc kT thuat mo quoc te - 2010 mo tien tien vi su phat trien ben virng K e t qua phan t i c h trang thai ap lire phan bo x u n g quanh k h u virc k h a i thac k h i khai thac v i a bang sir d u n g he t h o n g k h a i thac cot dai theo p h u o n g cho thay, ap lire tua I o n nhat tap t r u n g d p h i a t r u than bao ve sat g u o n g k h a i thac, t r o n g v i t r i ap lire tua l d n nhat nam v i a than K e t qua phan t i c h m d h i n h sd sir dung phan m e m F L A C cho thay v i t r i ap lire tua ldn nhat tai t r u bao ve loc doc v i a b i anh h u d n g b d i gdc ddc cua v i a than H i n h va H i n h mo ta trang thai c u d n g ap lire thang d u n g tac d d n g len cac t r u bao ve dau va chan l d cho cua he thdng nghe k h a i thac g u o n g l d c h o dai So phan b d ap luc tren H i n h cho thay, k h i gdc ddc v i a tang len, ap lire tua ldn nhat tren t r u bao ve p h i a tren l d c h o d i c h chuyen dan dan tir giira v i a than x u d n g k h u vuc l d p da t r u v i a than T i r ket qua phan t i c h cd the nhan d i n h l d doc v i a t h d n g g i d d 16 cho cd gdc ddc l d n cd n g u y c o b i b u n g nen cao h o n l d doc v i a t h d n g g i d tai v i a cd goc doc thoai h o n c, a = 30° d, a = 45° Hinh Dudng phan bo dp luc tua tqi tru than phia dudi lb chp cdc dieu kien goc doc via A n h h u d n g cua gdc ddc v i a t d i sir phan b d ap l u c t u a the h i e n r d h o n tai t r u bao ve phia d u d i g u o n g k h a i thac n h u the hien t r o n g H i n h So phan b d ap lire d u n g tren Hinh cho thay, k h i gdc ddc v i a tang, v u n g ap l u c tua l d n nhat d i c h u y e n tir k h u virc v i a than len v u n g vach da H i n h t r i n h bay trang thai ap lire theo p h u o n g d u n g d g i u a v i a than tir v i t r i 4m v u n g sap den m chieu r o n g t r u than bao ve 16 doc v i a v a n t a i t r o n g cac dieu kien goc doc v i a khac K e t qua phan t i c h tir H i n h cho thay, t r u bao ve 16 doc v i a van tai d v i a ddc n g h i e n c h i u ap lire tua nho h o n so v d i cac v i a ddc t h o a i 360 Hpi nghi Cong nghiep khoa hoc kT thudt mo quoc te - 2010 mo tien tien vi su phdt trien ben vung 40 J5 10 g 20 > & 15 10 u t **ằ**ô / hi j ,*i / ã • * — -4 0 degree 15 degree 30 degree 45 degree 12 IS 20 24 28 32 J6 The distance torn the edge o< longv/all panel, m 40 Hinh So dp luc dirng giira via than tqi cdc vi tri khdc tru bao ve lb doc via cdc dieu kien gdc doc via B a t r i so khac cua he so giira ap lire ngang va ap lire thang d u n g (ah/ay) la 0,33, 1, ya t r o n g hai dieu k i e n goc doc v i a ( n a m ngang va v i a co doc ° ) da d u o c m o phong de nghien c u u anh h u o n g cua ap luc ngang den v i t r i v i i n g ap lire tua tai t r u bao ve 16 doc ,via K e t qua phan t i c h tren m o h i n h so cho thay ap luc ngang cung co anh h u o n g den su phan bo ap lire tua t a i t r u bao y e 16 doc, v i a k h i k h a i thac v i a day bang he thong k h a i thac cot dai theo p h u o n g T r o n g t r u o n g h o p v i a n a m ngang, ap lire ngang anh h u o n g k h o n g n h i e u den su phan bo ap luc tua,tai t r u bao ve 16 doc v i a H i n h cho thay d u co sir khac biet ve he so giua ap l u c ngang v a ap lire d u n g la 0,3,3; l j v a 2, v i t r i v u n g ap luc tua I o n nhat v a n n a m cung v i t r i ben t r o n g v i a than Ket qua phan tich chi rang, dieu k i e n v i a n a m ngang, c u o n g ap luc tua I o n nhat tai t r u bao ve 16 doc v i a se g i a m k h i he so g i u a ap luc ngang v a ap lire d u n g tang T u y nhien khoang, each tir g i o i han g u o n g k h a i thac den v i t r i ap lire tua I o n nhat k h o n g thay d o i k h i thay d o i cac gia t r i he so giira ap luc ngang va ap lire d u n g n h u the h i e n tai H i n h T r o n g dieu k i e n v i a doc ° , tir ket qua m o h i n h so cho thay v j t r i v i i n g ap lire t u a I o n nhdt thay d o i I o n k h i thay d o i gia t r i he so g i u a ap lire ngang va ap luc d u n g T r u o n g h o p k h i ap luc ngang thap h o n ap l u c d u n g , v i t r i v i i n g ap luc tua I o n nhat n a m tren phdn l o p da vach, each x a v i a than K h i tang he - c,k = 2.0 so g i u a ap lire ngang v a ap luc dirng, v i t r i v u n g ap l u c t u a I o n nhat d i chuyen dan dan x u o n g v i a than n h u t h i h i e n h i n h T i r ket qua phan t i c h co the nhan d i n h t r o n g dieu k i e n goc d6c v i a k h o n g d o i , t r u bao ve t r o n g d i e u Hinh So phdn bo dp luc tua tqi tru bdo ve vdi cdc he so k =cr /o khdc d via bang h v 361 k i ? n he so giira ap lire ngang v a ap lire thang d u n g thap h o n se c h i u ap luc tua Hdi nghi Cdng nghiep khoa hoc ki thudt md qudc te - 2010 md tien tien vi sir phdt trien ben virng nho h o n so v a i he so giira ap lire ngang 45.0 40 35.0 3O.0 =5 | 250 va ap lire dirng cao h o n H i n h t r i n h bay trang thai ap lire tua tai cac v i t r i khac t r o n g t r u bao y.*r •*" vi*'"^*"~"™ ^T."'.V? ^ S 150 > 10.0 50 00' -10 20 ve 16 doc v i a van tai K e t qua phan t i c h tir H i n h cho thay k h i he so g i u a ap luc ngang va ap luc d u n g g i a m , c u o n g l a n nhat cua v u n g ap luc tua tren t r u bao ve 16 doc v i a v a n tai se g i a m theo X u h u o n g b i e n d o i t r o n g dieu k i e n v i a doc trai n g u o c v o i dieu k i e n via bang, k h i ma c u o n g ap lire tua l a n nhat tai t r u bao ve tang k h i he so g i u a ap Hinh Bieu trqng thai dp luc dung vdi cdc he so k=CTi/cr khdc dieu kien via bang v luc ngang va ap luc dirng g i a m „~— \ | i^ N - ip- = ™ b, k = 1.0 a, k = 0.33 V" '\ \ ' \ i y' ' I P / c, k = 2.0 Hinh So phdn bo dp luc tqi tru bdo ve Id doe via van tdi vdi cdc he so k=o /o A O dieu kien via ddc 30" t v khdc 35 30.0 i 25.0 i 20.0 k = 0.33 • k=1 k=20 | 15 ' 10 • !J 5.0 0.0 12 16 20 24 28 32 36 40 Distance from the edge of nb pillar, m 362 //hz// JB/