KHOA HOC VA CdNG NGHE MO
XAC DINH CAC THONG SO SOT LON, DICH CHOYEN, DIEN DANG MAT DAT DO KHAI THAC HAM LO VONG QOANG NINH
TS. KIEU KIM TRUC
Tap doan Cong nghiep Than-Khoang san Viet Nam
1. Gio'i thieu chung
Cdng tac khai khoang tao nen eac khoang trdng, lam mit thd can bang tir nhien cua Crng suit trong Idng dit, gay nen cac hien tupng djch chuydn bidn dang dit da va pha huy cdng trinh, mdi tardng. Ddi vdi md him Id, sau khi khiu than pha hoa da vaeh, sy dich chuydn bien dang lan ddn mat dit, lam bidn ddi ehe dp thuy van, mdi tardng, sut lun dit dai, hu' hai cdng trinh, dudng Id, buc khi, buc nirdc vao Id khai thac, tang ap lyc md, tang nguy co ty chay than... Ndu dd lai tai than bao ve qua be se din ddn nhung thiet hai tren, ndu qua Idn se dan ddn nhCrng tdn thit khdng eln thidt. San xult gia tang, khdng gian khai thac md rpng, cac dudng Id d cac mCre khac nhau hoat dpng trong vung anh hirdng cua nhau, khai thac than du'di moong Ip thien, dirdi dudng phd, sdng hd, rirng cay, ddng rupng, chua chidn... thi ddi hdi vd sy hidu bidt va didu khidn qua trinh djch dpng, dam bao an toan cho cdng trinh, giam tdn thit than cang trd nen cin thidt.
Bidn dang do khai thae him Id xay ra kha phd bidn.
6" md Mao Khe tram quat d mCre 142 m bj hdng, phai su'a chCra nhidu Iln, gidng khoan Via bj buc nu'dc vao Id via 9, Id xuyen via 56 bj bidn dang (nhCrng nam 1980'), buc cat va nudc vao Id qua phay A (nam 1995). Tai md Thdng Nhit nam 1998 bj buc nudc vao Id 60 tCr moong Id thien each 20 m, tai md Mdng Dirong khu trung tam via G9 bj buc nude tCr Id khai thac cu vdi lu'u lupng cP luc 200 m^/gid, tai md Tay Khe Sim bi buc nu'dc thang 8/2008....
Tren thd gidi tCr thd ki 19 "Djch ddng dit da" da trd thanh mdt bp mon khoa hpc lien nganh quan trpng. Mat dit md him Id dupe quan trie, khao sat thudng xuyen, lau dai bing nhidu phirong phap dd xir li va dy bao bidn dang kjp thdi. Cac thdng sd qui luat djch dpng dupe he thdng hPa, tdng kdt cho tCrng bd than, tCrng dang clu tnJc ^ a ehlt, tirng didu kien khai thac thanh ngan hang du' lieu phuc vu tien loi ngudi san xult, lam CO sd cho cac giai phap kT thuat chinh xac va thich hpp.
O Viet Nam thudng bj dpng ddi phd vdi bidn dang, ddng thdi dung cac thdng sd djch ddng cua vung than nudc ngoai mpt each thidu can cd chinh xac. Nghien cuu djch dpng bidn dang dit da la nhiem vu qui djnh trong qui pham khai thac md. Dd la cdng viec lau dai.
tich luy tu-ng giai doan mdi ed sd lieu khi eln thidt dd su' dyng. Cin phai coi chuong trinh nghien cCru djch ddng dit da nhu mpt qua trinh, he thdng, nhiem vu lien tuc trong san xult kinh doanh md dd dam bao muc feu san xult an toan, tdt kiem, khai thac hpp If tai nguyen, mdi tardng va xay dyng eo sd phap ly dung din.
a) b)
H. 1. Nirt tudng nha d Mdng Duong (a) va nui mat dit thanh them bac d Nam Miu (b).
Chinh vi vay trong nhidu nam qua bit diu tCr nhirng nam 1980' cac chuyen gia Lien Xd cu va can bp Cty UPng Bf, Cty Cim Pha, can bp Vien KHCN Md kdt hpp cung md Mao Khe, Thdng Nhit, XN TDKS4 da xay dyng cae tram quan trie djch dpng tren mat dit Id chp via 6 Trang Khe 2 nam 1983-1984, via 9b trang Khe i (khu 2A) nam 1985-1986, via Dly khu LP Tri md Thdng Nhit nam 1988-1991, va mdi day nhit tCr 2005-2008 la eae tram tren Id chp md Mdng Duong. Kdt qua xir li phan tich sd lieu quan trie da dua ra nhirng nhan xet danh gia thdng nhit vd cac thdng sd djch ddng.
2. Xay dung va xu' ly s6 lieu tram quan trie djch dpng Tram quan trie bao gdm eac didm mdc d mat dit phia tren Id ehp dang khai thac, dupc bd tri theo qui tic quan trie djch dpng [1]. ChCing dirpc xac djnh tpa dp tarde, trong va sau khi khai thac than dd theo ddi djch dpng, qua dd tinh eac dai lupng dieh dpng bidn dang theo cac tuydn bao gdm: Dich chuydn ngang t^, mm;
Djch chuydn dCrng (dp lun) ri, mm; Vec to dich chuydn b, mm; Bidn dang ngang E va; Bidn dang dCrng - dp nghieng I va dp cong K.
^ = (Dn+rDn),mm; (1) 11 = (Hn.i -Hn), mm; (2)
CONG NGHIEP MO SO 2 - 2009
CNM KHOA HOC VA CONG NGHE MO
b = V ? ^
s = (dM-di)/d, 10 mm;
,-3
(3) (4)
l = (TlM-Tii)/m,10-' (5) K = (lw-li)/m, 10"' (6) _
Trong dd: n - ThCr ty dpt do; D - Khoang each tCr mdc quan trie ddn cd djnh, mm; i va i+1 - ThCr ty hai mdc kd nhau; d - Khoang each giCra cac mdc, mm; m - Khoang each giira 2 vec to, mm.
Gdc dieh dpng dirpc xac djnh bing each ndi bien Id chp vdi cac didm mat dit cd cac gia tri tdi han sau:
K=0,2x10"^1/m; 8=2x10-^; 1=4x10"^; Gdc dut tach gidi han vung nut ne dupc xac dinh bdi doan thing ndi bien Id chp tdi khe nCrt ngoai cung; Gdc lun eye dai - giira Id chp ddn didm cd dp lun eye dai. He sd eCrng cua dia ting duoc xac dinh theo phirong phap taing binh trong sd:
f=(30fc+70fj/100 (7) fc, fm = Smif/Emi _ (8) Trong dd: fc, fm - He sd eCrng (theo Prdtddiakdndp) cac
Idp da cat kdt, san kdt, bpt kdt, set kdt, set than...; mi- Chidu dly Idp da, m; fj - Dp eCrng Idp da thCr i.
5 = 78°
H =-100m
H.2. Xu ly tram quan trie dich ddng Id chg 61 via 6 (a) va 2A via 9B (b) md Mao Khe.
3. K i t qua XLP li s6 lieu xac djnh cac thong s6 dich dpng co* ban
Bang 1.
Viec XU" ly sd lieu dupc thye hien tren may tinh dien tCr theo ngdn ngir lap trinh basic. Cac kdt qua chinh cho tirng tram nhu sau.
Tram do sd 1 tren Id cho via 6 Trang Khe 2. Gdc djch dpng theo phuong via 5 = 80°, goc djch ddng theo hudng ddc xudng cua via p = 50°, theo hirdng ddc len cua via Y = 80°, gdc lun cyc dai 9 = 62°, gdc dCrt tach theo hudng ddc xudng p"=45°, dp eCrng dit da f = 5,8.
Thdi gian djch ddng la 7 thang.
Tram do sd 2 tren Id chp via 9b Trang Khe 1. Gdc djch dpng theo phirong via 5=78°, gdc dCrt tach theo phuong 5"=84°, gdc lun cyc dai 9=59°, dp eCrng dit da f=4,7. Thdi gian djch dpng la 9 thang. Tram do sd 3 tren Id chp via Dly khu Lp Tri md Thdng Nhit. Gdc djch dpng theo phirong via 5=80°, gdc djch dpng theo hirdng ddc xudng cua via p=59°, theo hudng ddc len cua via Y=83°, dp cCrng dit da f=6. Thdi gian djch dpng hon 12 thang.
Kdt qua danh gia sd lieu co If da, dp cCrng dja ting cac md than Quang Ninh khae cho thiy f dao dpng trong khoang 4,5 + 6.
Dya tren cac kdt qua xir li sd lieu quan trie djch dpng da neu, chung ta hoan toan cd co sd dk phan nhdm eae md than Mao Khe, Thdng Nhit ndi rieng va toan bd viing Quang Ninh ndi chung vao vung djch dpng sd i theo "Qui t i c bao ve cdng trinh va cac ddi tirong thien nhien chdng anh hu'dng cd hai do khai thac h i m Id gay ra" (LB Nga 1998). TCr do cd thd dua ra nhCrng thdng sd djch ddng co ban nhu sau:
a. Cac gdc djch dpng co ban: 5=Y=80°;
5o=Yo=70°.
b.Cac gPe djch dpng theo hudng ddc xudng p, Po phu thudc vao gdc ddc cua via than xac djnh theo Bang 1. Odi vdi cac via ddc, cac gdc djch dpng Pi, Poi phu thudc vao gdc ddc cua via than xac djnh theo Bang 2. Odi vdi chidu d l y via hon 4 m thi gdc Pi se giam di 5°. Trong trudng hpp dja ting da bj khai thac trudc thi cac gdc d a va b giam di 5°.
c. Gdc lun cyc dai du'pc tinh theo cdng thCrc:
9=(90-Kia). Kl - He phu thupc tl le giira chieu day Idp phu De TCr va chidu sau khai thac, xac djnh theo Bang 3.
d. Cac gdc dut tach 5", P", Y>" ldn hon cac gdc djch dpng 5, p, Y la 5°.
e. Thdi gian djch dpng va thdi gian bidn dang nguy hidm phu thudc vao tdc dp di Id va chidu sau khai thac, xac djnh theo Bang 4.
Cac gdc
P
Po
Gdcddc via than, a°
0 70 80
5 65 79
10 61 70
15 57 66
20 54 62
25 50 58
30 46 53
35 42 49
40 40 46
45 36 42
50 33 38
55 29 34
60 25 30
65 25 30
70 25 30
75 25 30
CONG NGHIEP MO SO 2 - 2009
KHUA HOC VA CONG NGHE MO
Bang 2.
Cac gdc Poi
Pi
Gdcddc via than, a°
50 35 55
55 40 55
60 40 50
65 40 55
70 40
75 40 -
Bang 3.
h/H Ki
0 0,9
0,1 0,82
0,2 0,73
0,3 0,64
0,4 0,55
0,5 0,46
0,6 0,36
0,7 0,27
0,8 0,18
0,9 0 Bang 4.
H 50 m 100 m 200 m 300 m
Thdi c V= 15-20
7 9 16 21
lian djch dpng, thang V=30
5 6 13 18
V=50 4 6 10 13
Thdi gian bien dang nguy V= 15-20
3 5 7 9
V=30 2 4 6 7
liem, thang V=50
2 3 5 6 Ghi ehu: V - Tdc do di Id, m/thang; H - Chiiu sau khai thae, m.
4. Ket luan
Trong luc edn han chd vd sd lupng va npi dung nghien cuu thi nhu'ng thdng sd vd djch chuydn bidn dang mat d i t g i n dung tren day da dupc sCr dung r i t cd hieu qua dd xu' ly cac v l n dd lien quan nhir xay dyng tru bao ve dudng dtd tren md Deo Nai, thidt kd cac tram quan trie djch ddng va tru bao ve dudng s i t tren md Mdng Duong...
Mdt sd dac didm c i n chu y trong nghien eCru bidn dang djch chuydn mat d i t d Viet Nam la phin Idn dja hinh khu kliai thac h i m Id la ddi nui, sudn ddc, g i n Id via, dCrt gly, chidu sau khai thac ndng, tdc dp khai thac cham, didu khidn da vach theo phuong phap pha hda toan phin. Qui luat djch dpng phCrc tap vdi nhidu ydu td b i t ngd. Do dd can dd cap cae ydu td nay dd nghien cCru va xiy \y sd lieu. Nghien eCru djch chuydn bidn dang mat dat do khai thac him Id gay ra la mpt qua trinh lien tuc, bao quat, tich luy d i n d i n cd kd thCra bd sung.
Dupc sy quan tam cua lanh dao Tap doan TKV, hien nay nhidu tram quan trie dang dupc Vien KHCN Md kdt hpp vdi cae edng ty than xay dyng va do "dac trong vung Quang Ninh dd ehinh xac hda cac thdng sd djch dpng nhlm muc tieu san xult an toan, tidt kiem.•
TA! LIEU THAM KHAO
1. Dupak I.N., Nguyen Trpng Hoan, Nguyen Binh, Kidu Kim True, T r i n Van Ydt, Pham Dai Hai,... Nghien eCru dp dn djnh da vach tru cac via than chinh vung Quang Ninh. Bao cao tdng kdt dd tai c l p nha nu-dc.Vien NCKHKT Md. Ha Noi.
1986-1990.
2. Kliutrnhicov I.N., Kidu Kim True, Nguyen Chau Dien, Nguyin Tam Son. Quan trie va Xac djnh cac thong sd djch dpng mat d i t khu Trang Khe md Mao Khe. Cty than Uong Bi-Vien KHKT Md. UPng Bi. 1985.
3. Kidu Kim True. Xac djnh eac thdng sd djch chuydn mat d i t khu Lp Tri md Thdng Nhit va hieu ehlnh tru bao ve dudng dtd len md Deo Nai.
Vien NCKHKT Md. Ha ndi. 1991.
4. Nguyen Tam Son, Nguyen Tidn Chung va nnk. Kdt qua quan t r i e djch dpng md Mdng Duong. Vien KHCN Md. Ha Npi. 2005.
5. Qui t i e bao ve cdng trinh va ddi tupng thien nhien chdng anh hu'dng co hai cua khai thae h i m IP. Vien VNIMI, LB Nga. St. Petersburg. 1998.
(Ban tidng Nga).
Ngudi bien tap: Dao Die Tao
m^Mi
k'Hii^i'^
l a r e l o ^ P H H I P ^ n g Ninh;coal basin, a
\regiori pWith'^'p^Bbmplicated mountainoijs topography, while full roof cavity is appliedv:
causing a lot of land subsidence. Amid limi^
number of subsidence observation and land isubsidence study;; pointing out adeo'^*i^
fsubsidende parameters for Quang Njnll
"basin Has been very actual and it has been"
;done well since 1 9 8 C | * - " " - " " " " ^ ' " " * ' " " "
corrected all the time;«J
CONG NGHIEP MO SO 2 - 2009
