r r Hdi nghi khoa hoc kT thuat mo quoc te 2010 Cong nghiep md tien tien vi su phat trien ben vitng NGHIEN CUTJ MOT SO GIAI PHAP TONG HOP NHAM NANG CAO O N D I N H D l T C ) N G L O D O C V I A T H A N[.]
Hdi nghi Cong nghiep r r khoa hoc kT thuat mo quoc te - 2010 md tien tien vi su phat trien ben vitng NGHIEN CUTJ MOT SO GIAI PHAP TONG HOP NHAM NANG CAO O N D I N H DlTC)NG L O D O C V I A T H A N A P L T / C M O LO^N TS.Le Van Cong, TS Pham Minh Due, KS Pham Tiln Vu V i e n K h o a hoc C o n g nghe M o - T K V Tom tat: Tai mqt so md than viing Quang Ninh cac nam qua so luong cdc dudng Id phdi chong xen lai chiem ty trqng rdt ldn, gay ton that ve kinh te vd han che den san xudt than Vien KHCN md dd ket hop nghien cuu ly thuyet vd thirc nghiem tai hien trudng vd tim nguyen nhan gay mat dn dinh duong Id dan den phdi chong xen nhieu ldn Bdi bao gidi thieu phuong phap tiep can vd cdc gidi phap dd dp dung de nang cao dn dinh cdc dudng Id nam viing ddt dd cd tinh truong nd cao Tai cac via than Quang Ninh, dac biet khu vuc mo than Mao Khe cau true via than rat phuc tap V i a day, doc, phan l o p , phan phien, nhieu l o p kep m o n g , ben than va dat da tru vach k h o n g cao nen sau k h i dao chong 16, ap luc tang nhanh gay bien dang pha huy ket cau chong M a c d u m o t so n a m vira qua k h o n g n h u n g M a o K h e m a m o t so m o khac da sir dung n h i e u loai ket cau chong va b i e n phap gia c u o n g n h u n g ket cau chong v a n bi bien dang pha h u y , t h o i gian t o n tai cua d u o n g 16 van chua cai thien Tang o n d i n h cua d u o n g 16, keo dai t u o i tho ket cau chong 16, g i a m chi p h i chdng xen, sira chua, tang t h u h o i , sir dung lai nhieu lan k h u n g chong can p h a i t i m nguyen nhan, ly giai cac nguyen nhan va lira chon cac nguyen l y p h i i h o p t r o n g dieu k i e n cu t h i cua m o t viing, mot k h u v u c Qua khao sat, dac ap lire m o tai cac d u o n g 16 doc v i a than m o than M a o K h e , l i y mau t h i n g h i e m t r o n g p h o n g dac diem truong n o ciia m o t so loai nham thach, so bo buoc d i u chiing toi co nhung suy n g h i sau: - V i a day, k h o n g o n d i n h - Than, cac l o p kep co t i n h t r u o n g n o m a n h - V i a cau tao phan l o p , phan phien - V a c h t r u m e m y e u t r u o n g no, chiia ham l u o n g m i c a nuoc cao - Lien he giua nuoc mat va via than tot, k h i than da b i ngam nuoc ben giam manh - K e t cau c h o n g chua h o p l y Ket qua t h i n g h i e m t r o n g p h o n g va h i e n t r u o n g m o t so t i n h chat co l y than da M a o Khe va m o t so m o khac ( T h o n g Nhat, D o n g R i ) m o t v a i n a m gan day co t h i n i t m o t sd nguyen nhan co ban sau: I M o t so n g u y e n n h a n c o b a n M o t so n g u y e n n h a n ve d i a k y t h u a t gay ap l u c l d n l e n k e t cau c h o n g Qua nhieu n a m k h a i thac va dieu k h i e n da vach bang pha hoa cho n h i e u v i a lien t i l p Khoang k h a i thac l d n Sap da vach l a m cho l d p da p h i i ben tren sut l i i n theo tao dieu kien thuan l o i cho nude mat chay vao m o ( d u k h o n g m u o n the) Sir co mat ciia nude mat ket h o p v d i nude t r o n g m d l a m cho cac d u d n g l d de b i n g a m nude hoac n h i l u hon la b i sung nude 505 Hpi Cong nghi khoa nghiep hoc md tien kT thuat tiin mo quPc vi su phat ti -2010 triin bin vung V d i cac l o p set deo, set than h a m l u o n g h y d r o m i c a cao n e n t i n h t r u o n g n o lan Theo ket qua n g h i e n c u u n h i e u n a m cua V i e n K H C N m o , t6c t r u o n g n d cua set k i t , set than, bdt k i t k h u v u c M a o K h e cd he sd t r u a n g n d tir 25 tr % ( h i n h 1), t i c bung nen dat t d i 50 + 60 cm/thang ( H i n h ) M a c d u duoc c h d n g g i u t u o n g d d i kien cd, co d u d n g 16 k h u n g c h d n g thep " I " l i i n c u n g k h o n g the chdng l a i d u g c ap luc va bimg nen lam cho ket cau chong b i b i e n dang va pha huy M o t sd doan l d dgc v i a than dien tich duong 16 m chi sau thang b i t h u hep c h i k h o n g den m 2 Dat da b i t r o i len t r u o n g n d the tich The t i c h dat da b i t r o i chuyen vao cong t r i n h dugc L u l k i n V A de xuat [ ] t i n h theo cdng thuc (1) V = 4.(1 -M ).L n.y.H 4.k A 2.k X x (1) v h0 Trong dd: a A = arccos(—) L a B =- J \ - ( - Y V L ,a a -(-).arccosL L E va u - cac hang sd dan hdi ciia da kep; L = (1+a) - a nira chieu rdng duong 16; ki G i d i han chay t i n h hgc theo b i e n dang t r u g t , cat ciia l d p da b i m g nen Gia t r i the t i c h dat da t r o i vao cdng t r i n h t i n h cho m chieu cao ciia nen l d b i nang len dugc xac d i n h theo (2) v = ^" (2) nen cdng t r i n h ngam, hay 2.a A p luc b i i n g nen K h i dat da b i t r u o n g n d t r o i vao t r o n g l d L u g n g the t i c h t r o n g qua t r i n h troi vao 16 gay nen ap lire t r u a n g n d l d n [ ] K h i t r u a n g n d dat da c h u y e n v i vao h d n g l d tao nen mot ap lire hong theo ( ) : 90° - P =(y.H P ).tg (2 l dl+ -) (3) L u c day h o n g Pi se gay nen lire day hong bac h a i T i e p theo cac luc se gay nen ap lire P tir phia nen 16 v d i gia t r i ( ) : 90°-^ P =(y.H P ).tg\2 Jl+ -) (4) Theo [7,8] ap lire t r u o n g n d ciia set deo, set than dao d d n g tir tr k G / c m T6c t r u o n g n d v a the t i c h t r u a n g n d d u a c t h i n g h i e m bang p h u a n g pha dao v o n g , ket qua tai hinh(l) T d n g h g p cac dai l u g n g t d n g h g p tren la n h u n g nguyen nhan l y giai t a i met 16 chdng xen t r o n g cac n a m gan day cao 506 Hoi Cong nghi khoa nghiep md hoc tien ki thuat tiin Toe truong no% md qudc vi su phat te - trien ben 2010 viing Xa va cot bi thu nho 30 20 10 ( Hinh 2: Su tliu nhd lb dp luc vd bung 10 12 14 16 18 20 22 24 thai gian Hinh 1: Bieu lien h$ giua truong nd vdi thdi dudng nen gian A p l u x n e n h o n g V i a than, da b i phan phien phan l o p , k h i v i a cang day t h i kha nang khang lai ap lire cang Ion [9] (bang ) Chi tieu Don vi Chieu cao h m Pham vi su dung chi Nhd nhat Trung 0.25 Khau dam 2a m MPa 2.0 10 Dp ben ciia dat da [