Thong tin khoa hpc cong nghe m o \l THIET KE KET CAU CHONG TREN CO SOT PHAN TICH DICH CHUYEN The geomechanical processes in rock mass around the dnfts in the coal mining region Quang Ninh has been analysed by using Phase and parametric studies Combining the simulation results with the displacement measurement results in different coat mines allows building of relationships between the boundary displacement at the support installing time, the maximum boundary displacement of dnfts, the boundary displacement by equilibrium state and the relevant geomechanical and geometric parameters, like UCS, the in-situ stress and the drift-span Subject to all regulations, the steel arch support can be chosen and design on the basis of obtains relations D | t v i n dd Cho d i n nay, e^c cong trinh ngim khai thac mo da dugc quy hoach, thiet k i theo cac quy dinh, hudng ddn hipn hanh tuong ung vdi eac dieu kipn dja chit, dia eo hgc, nhan dugc tu cac tai lieu dia chat va cac tham s i eg hgc cua da, khii da Trong thiet ke, ciJng da co sy kit hgp vdi eac kinh nghidm tu thiet ke, thi cong d nude ta Tuy nhidn, mdi trudng dja chit v i n rat phue tap, duge hinh tu hang tripu nam, bl biin doi bdi eac qua trinh npi, ngoai sinh khac nhau, vay, cac kit c i u ching can dugc dieu ehmh che phu hgp vdi dieu kidn dja chit eu t h i Tren eg sd Ceic kit qua nghidn cuu cua co hpc da, CO the thiy rang, moi biin dgng ve dja chit, dia eo hpc se dugc phan anh qua bieu hien cua khii da xung quanh khong gian ngim Ngoai cac hien tugng pha huy, kho nhan biit d sau khoi da, thi djeh ehuydn trdn bien him, 16 la hipn tugng de dang quan trac dugc, tham chi mgt s i trudng hgp co the cam nhan dugc Tu cho thiy, quan trie djeh chuyin se cho phep CO dugc nhan djnh khach quan v i bidn d i i eg hpc, ve e^e hau qua co the xay khii da Tuy nhien, djeh ehuydn cung d6i hoi nhieu thdi gian va nhan lye TS PHAM VAN THUONG KS NGUYEN DlNH THINH KS NGUYEN CHiTRydNG Cdng ty than Duong Huy- TKV GS.TS N G U Y E N QUANG PHlCH Dai hoc Md- Oia c h i t Bien tap: T$ Pham Minh Bi>c la cae "thi nghidm ao" Bang each c6 thd nhan dugc quy luat anh hudng cua cae tham so dau vao (dae bipt la cac tham so v i dieu kidn dja chit, dja CO hpc) den cac qua trinh, cac hipn tugng can nghidn euu Phoi hgp eac kit qua dac va mo phong s i se c6 dugc eae nhan dinh d i y du hon ve eac bidu hidn cua khoi da xay dung cong trinh ngim va khai thac mo Bai viit gidi thieu kit qua nghien cuu kit hgp mo phong s i , thong qua phan tich tham s i dua trdn cae dieu kien dja chat, dja co hoc eua cac mo him 16 vung Quang Ninh, vdi kit qua dich chuyin de xay dyng cac m i l tuong quan giua dich chuyen trdn bidn cac dudng 16 vdi eae yeu to anh hudng co ban, tu d6 cho phep de xuat dugc phugng phap lua chpn, thiet k i kit c i u chong Co* s d [y thuydt va phirong phap nghien ciru mo phong Sau dao cac dudng 16, diiu kidn can bang ty nhidn cua khoi da bj pha vd, c6 bien d i i v i vat chit, cu the mpt bg phan nhan va truyin tai trudc day da bi l i y di Trong khii da se hinh mpt trang thai co hgc mdi c6 thd dan den pha huy hoac khong, thugc vao tuong quan Ngay nay, nghien euu li thuyit, cac giua "lye tac dyng" va kha nang nhan tai cua phuong phap s i cho phep c6 t h i chu y tdi nhieu khii da [1] Nhung bien d i i ve trang thai ung yeu t i khac nhau, anh hudng den bai tpan bien, suit sd gay djeh ehuyen va biin dang trcng hinh xay dyng cong trinh ngim va khii da, vdi xu the la djeh chuyen ve phia khai thae ham 16 Cac phuong phap s i cho phep khoang tring, Od han c h i biin dang va ngan thyc hien phan tich tham s i , nghTa la nghien cuu ngua da bj pha huy sap Id vao dudng 16, nhat cac qua trinh xay vdi su bien dong cua cae thiit phai l i p dyng k i t c i u ching, khii da tham s i dau vao Cung vi t h i , phan tich tham so m i t i n djnh Giua kit c i u ching va khoi da vay bang cac phuong phap s6 da va dang dugc coi quanh co tac dgng tuong ho Neu khong su KHCNM S 11/2014* CNKT HAM LO Thong tin khoa hpc cong ngh$ mo dung kit cau chong linh hoat, hoac kit c i u ching da hit dp linh hoat kieh thude, thi djeh chuyin cang Idn, kit cau ching sd chiu ap luc cang Idn Trong thyc te, cac kit eiu ching da duoc thiit ke trude thi edng, dugc diiu ehinh thi cong Bo djeh chuyin de xae dinh ap lye hiu nhu khong dugc thuc hien Cac phuong phap ap luc kha t i n kdm, vi vay, d i n chua dugc ap dyng rpng rai tai Viet Nam Cung vi the, vide danh gia ap luc khong thyc hien dugc thong qua trye tiep tu d i u ap luc (ap lye k i , t i bao ap lye) hoae eac d i u bidn dgng (sen so biin dang) Xuit phat tu gia thiit la kit cau ching va khoi da ciJng biin dang, c6 thd dya vao kit qua djeh chuyen va "dp cung" cua kit c i u ching de suy ap luc da biin dang, hay "ap luc thuc sy" [2] Bieu thue duoc xay dyng bdi Beiaeneo eua Nga va Otto Mohr cua Diec vao nam 1954 [3,4] nhu sau Uco(q) = Uo+U(q), (1) Trong do: Uco(p) - Chuyen vj cua khoi da d i n thdi diem thiet lap can bang tmh cua he "kit c i u chingkhii da"; Uo- Chuyin vi ban d i u cua khii da tu thdi diem khai dao d i n thdi didm l i p dyng kit c i u ching vao trang thai lam vide; U(q)- Chuyin vj trdn bien cua kit eiu chong den thdi diim thiit lap can bang tmh he "kit eiu chong-khii da" [5], phan tich cac chT tieu eo hgc theo [6] q- La phan luc cua kit c i u ching, eung la ap lye da len kit c i u ching Tren co sd do, bai toan mo phong 6\jcfc xay dung dua theo cac dieu kien hien tai cac mo than him 16 d Quang Ninh, su dyng chuong trinh s i PHASE2 khii da, dugc don gian hoa, thong qua cac he s i nhu giam bin eiu true, he s i ehu y tinh luu bien, he s i chu y giam ben tac d6ng eua nude.[7,8,9], So d i bai toan mo phong so vdi cae diiu kien, eae tham s i dugc su dyng de phan tich tham so, dugc t h i hien tren hinh Cac tham s i hinh hpc va eo hpc co ban dugc su dung dao d6ng cac khoang bien thidn sau: - Tlit didn dao Sa = 13 -:-18 m^ n KHCNM S 11/2014* CNKT HAM LO - Chieu sau dat '' ^^.y^^ ^^^.^ dudng ham H = 300 -:- 600m- - Cudng dp khang ndn don true On - 20-:-50 MPa Mot sd kit qua nghien ci^u 3.1 Phan tich qua trinh bien doi - i ^ a CO' hgc bang Phase2 Cac bai toan md Hinh Md hinh tinh toin phong bang phin mem Phase theo mo hinh nhu trdn hinh 1, dugc thu'c hipn bang cac thay doi cac thong s i dau vao Cae thdng so dja co hoe cua khii da nhu b i n nen don true an, mo dun bidn dang E, luc dinh k i t C, lugng t h i tich y, goc ma sat tp, g6c dan nd v|/, hp so Possion |i, ben du oo, he s i ap lue ngang k duge lua chgn tu [7] va kit hgp xu ly theo [6] Ting the, da tiin hanh phan tich 48 bai toan khae [10] Dd theo doi qua trinh biin dang va pha huy eua khii da, mdi bai toan bidn da tidn hanh khao sat 10 trudng hgp vdi cac gia trj ap lgc khac tu ben dudng 16 (phan lye cua kit eiu chdng) Cudng dp cua phan luc dugc chpn giam dan tu cudng dp eua ung suit nguydn sinh ve d i n Tren hinh ia mgt vl du v i kit qua tinh cho bidu d i phan b i ung suit Oil khii da xung quanh dudng 16 tai tlit dien 13m^, d sau 300m, da co dp bdn nen bing 50 MPa Hinh eho thiy, vdi q du Idn, khii da co biiu hidn dan h i i , phin ung suit 00 giam dan tu bidn cong trinh theo khoang each vao sau khoi da; vdi q du nho (trong trudng hgp q= 0,4P=0,4YH) khoi da xung quanh dudng 16 se xuit hidn vung pha huy Vdi q= p= y H, duong nhien tren mat c i t ngang theo true nam ngang ung suit ao la khong doi ^ ^ ? ^ Tu cae k i t qua mo phong nhieu m6 hinh, vdi sy thay d i i eua eac thdng s6 theo so trdn hinh 1, CO thd k i t luan rang, chuyin vj bien ban dau d i n thdi didm l i p dat kit c i u chong (Uo duoc xac djnh tuong doi xung quanh dudng h i m chua xuat hidn vung biin dang khong dan Thong tin khoa hpc cong ngh§ m o Khoing cich ke tCe bien dud'ng Id -4-q=p -^-q=0,8p -(-q=0,4p —q=0,04p —q=0,02p -q=0,7p q=0.6p -^q=0,01p -*-q=0,5p -q=0 0,1 0.2 0.3 0,4 0.5 0.6 0.7 Hinh Bidu dd quan he ehuydn vj bien ban diu cOa yH/oN khdi di xung quanh dwdng Id Hinh Bidu dd phin bd Ong suit khdi da xung quanh dudng Id tai siu 300m, tidt dien 13rr^, bdn ndn cOa di 50 Mpa theo mit cit 1-1 hinh hoi hay deo) vao trang thai lam vide khdng vugt qua 43mm, e6n ehuydn vi bidn Idn nhat din thdi diem thiit lap can bang tTnh cua hp "kit eiu ching-khii da" c6 the dat tdi 810mm, Tucaeso lieu nhan dugc cho phep thiet lap duge bidu giua Uo/Bdva yH/aN (hinh 3), theo bieu thuc (2): ^^£:i£i = S.238j"i^V-H5,748.2^-0,6-2, (2) Trong do: y - Trpng lugng thd tich eua da, MN/m^; H - Chieu sau dat dudng 16, m; oN- dp ben ndn don true cua da, MPa; Ba - Chieu rpng dao cua dudng 16, m Tu t i p hgp cae k i t qua nhan dugc tu caC mo hinh md phong, cho phdp lap dugc bieu thue chuyin vi Idn nhit trdn bien UM = f (y, H, ON, oNd, Ba) (vdi sal s i khdng vugt qua ±18,0%): B ffx Trong do; A = -5,8; B = 254,17, C - He s6 phu thupc vao b^n cua 3k da bao quanh du-ong 16, C = 11,2, aN = 20 MPa; C = 14,4, khioN = 30 MPa; C = 17,9, khicN = 40MPa; C = 18,5, CN = 50 Mpa; Tren hinh la vi du ve ket qua tinh l|p bilu dac tinh biin dang cua cua khoi da, H = 300-600m,nN = 20MPa, So=13nn^ 3.2 Nghien cum dich chuyen tai cac mo than Quang Ninh Tai cac mo than vung Quang Ninh, thu-ong si> q, MP3 Hinh Bidu dd quan he dac tinh chuyin vi-phin It/c cua kit ciu chdng tai bi§n cOa dudng Id H = 300- 600m, aN = 20 MPa, Sa=13m^ dung cac loai khung chong thdp Idng mang dugc c h i tao tai V\et Nam, nhung theo cac dang thep hinh cua Nga Khung chong thep Idng mang d dang ba doan, hai khdp co dp linh boat nhit dinh theo kich thude, vay, qua trinh chju tai, cac khung thu nho dan theo dich chuyen cung nhu ap lye tu phia khii da Qua trinh xay la qua trinh dung, niu hd kit ciu-khii da tiin din trang thai can bang Qua trinh se la khdng dung, trang thai can bang khdng duoc hinh thanh, kha nang nhan tai eua kit c i u chong khong tuong xung vdi dieh chuyin va ap luc da; hoac qua trinh su dyng, dudng 16 chju tac dpng cua khau khai thac, hoac chiu tac dpng cua cac ddi pha huy, nude, khi, ma khdng thd hidn tu ban dau Trong cac trudng hgp d6, djeh chuyen eua khoi da co t h i tang nhanh, d i n d i n pha huy, n i u kh6ng didu chinh kit c i u chdng eho phu hgp Do dieh ehuydn, ap lye eua khii da hinh bdi quan he tugng tac giCpa kit eiu chdng va khii da, v^y eo t h i djeh chuyin d i xac dinh ap lye da, k i t hgp vdi cac kit qua md phong bang phuong phap so Xuat phat tu nhgn djnh va gfa thidt nay, chung tdi da tiin hanh do, KHCNM s o 11/2014* CNKT HAM LO Thong tin khoa hoc cong nghe m o IS 30 s «o 'S » IDS 110 lis isongay dem Hinh Dich chuyin xung quanh dudng Id thong kS, cho ph4p xfly dirng du'po mli quan h? sau, giua djeh ehuyen a trung thai can bang tinh cua khoi da tren bien 16 vol cac tham s6 co hpc, hinh hoc dae tru'ng [10]; s (4) Trong do: D = -3,1; F = 222,48; C - He so phu thu6c vao ben cua dat da bao quanh duo'ng 16; C = 11,2, o„ = 20 MPa; C = 14,4, khion = 30 MPa; C = 17,9, khv tin = 40 MPa; C = 18,5, an = 50 Mpa 3.3 Vi dy ap dung tinh thiet lie khung Hinh So dd diydng Id, mit cat va vi tn chong: Bing Kdt qui dich ehuydn Sau day la vi du ap dung cac kit qua nghien Chu ky do, t ddm cifu d l xac dinh cae thong s6 cCia khung ching Hi^u so cho tru'ong hp'p mpt duo'ng 16 dupe dao qua 15 30 45 60 75 90 105 120 150 ipai d i t da, thpng s6 cu t h i lo?i d i t da dupe N1-N3 149 175 199 206 213 223 226 227 230 gioi thieu bang • Xac dinh chuyen vi ban dau va chuyen vi N2-N3 100 129 157 164 172 182 183 184 186 thai gian cua khoi da noc dwang Id theo doi dich chuyen tai cac du-ang 16 khac nhau, Djeh chuyin dan hoi trung binh UocCia c^c cho din ket cau chong va khoi da dat trang khoi da CO f=2 va f=5, dieu kien mo him 16 thai can bang tinh, nghia la dich chuyen khong vung Quang Ninh, du'pc xac djnh tif bleu thirc phat trien tiep, hay noi each khac, cho den (2), nhan cac gia tr| sau: djeh chuyin tiem can gia tri nhit djnh • K h i f = ^ Uo= 11mm Tren hinh cho thay nguyen tac lam viec cua • K h i f = 5-> Uo= mm gian k l hai dau Tren hinh la so bo tri Phin chuyin vi 16'n nhat dutac xac djnh theo dich chuyin bing gian ke Bang la so lieu va tren hinh la bieu dich chuyen, thoi bleu thirc (3), hlpu s6 ciia djeh chuyin 16'n nhat gian tif ket qua do, khung ching- khoi da dat va djeh chuyin dan hoi la djeh chuyen theo thdi gian Khi d6 co d i n trang thai can bing tTnh • Khi f = -> djeh chuyin 16'n nhit theo (3) Tir cac kit qua du'p'c nhilu dieu kien thu'c t l cua cac mo, sii dung phuong phap xCr ly U«.2 = 328mm-> dich chuyen theo thoi gian LI* 2-Uo-2 = 317mm KHCNM SO 11/2014* CNKT HAM L Thong tin khoa hpc cong nghe mo Bing TT Ten cac thdng sd Gia trj Di§n tich tiet di6n su' dung v^ 10,4, 13,0 tilt di$n aio - SM, Sa, m' Chieu sau dSt du'ang 16 - H,m 300 H6 s6 kien CO f cOa d^ theo den phan loai cua Protodiakonop M6 dun bi^n dang cua kh6i 1609; 10061 ai, E, MPa G6c ma s^t ciia khoi 210 den 430 3i, (p, dp Luc dinh ket - C, Mpa 0,4 din 1,25 • Khi f = 2, U(q) = 289 mm, q2 = 250*289/240 = 301 kN/m * Lira chon mat dp khung chong Mat khung ching linh hoat duge xac dinh thong qua sd khung ching eho Im 16, dya vao tai trpng xac djnh dugc cho 1m 16 va kha nang chju tai toi da cua khung chong Tu d6 co: Mat dp khung ching dugc xac dinh theo gia trj Idn hon, g i n nhit vdi gia trj tinh toan, tuc la f = 2, n2 = 1,34 khung/mdt (bude chdng He so Possion, ^ 0,35 din 0,26 0,75m); f = 5, ns = 1,0 khung/met Trgng luong the tich, y, Nhu vay, vi du tinh cho thiy, hoan toan co t h i 0,024 den 0,0255 MWm' xac djnh duge ap lye da tac dung len khung • Khi f = -*• djeh ehuydn Idn nhit theo (3) ching, xac dinh duoc mat dp khung ching, UM5 = 70mm -> djeh chuyin theo thdi gian U(*5 - thdng qua djeh chuyen, kit hgp vdi cae tinh chit cdng nghp eua khung ching (kha nang chju U&5= 68 mm tai, dp cung, cac thdng s i ve dp linh hoat ) Vi Dieh chuyen d trang thai can bang tTnh dugc xac du tinh toan va cac thdng s i cdng nghp duge d|nh theo (4) va nhan dugc k i t qua; tinh va liy theo cac kit qua nghidn cuu cua Nga, K h i f = - > U{q)= 289mm cae khung chong tai cae mo him 16 hidn • K h i f = ^ U(q)= 59mm ed xuit xu tCr Nga, hoae duge c h i tao theo ban Theo [3], chung ta co: U(q) = Ui + U2 + U3(q), quyen eua Nga vdi Ui - chuyin vi tinh toan d i n kha nang len Kdt luan va k i i n nghi chat eua vat lieu chen hay vO-a chen l i p khoang Djch chuyin cua khii da sau dao, ching tring, trudng hgp Ui=0; U2 - chuyin giu, gia co khoi da xay dyng cong trinh vj qua trinh ddng kin cac khe hd vi ngim la dai lugng cho phep cd the dugc don chong, neu k i t cau ehong la khung thep SVP thi gian nhit Nhidu dung ey va phuong phap da U2 = 0; U3(q) - ehuyen vj xac dmh bang dp cung va dang dugc ap dyng Gian k i la mpt kit c i u ching, xac djnh theo c6ng thdc- U3(q) = cdng cy da duge su dung d nude ta Djeh q/ko, vdi ko- he so eung cua khung chong, ehuyen la dai lugng phy thudc vao, hay phan MPa/m, phu thupc vao loai kit cau ching va mat anh anh hudng bdi nhieu yeu to khac nhau, bao dp hay budc chong cua chung [10] Nhu vay gom cac y i u td v i didu kidn dja chit, dja hinh; trudng hgp c6 U(q) = U3(q) eac ydu t i v i ^ a eo hoc; cae y i u t i cdng nghd, * Xac dinh tai len ket cau chong cd the dy bao thdng qua phan tich tham sd bang Vdi khung ching dugc lya chpn la SVP 22, cac chuong trinh s i , vdi vai trd la "ph6ng thi trdn eg sd kit qua phdng thi nghipm cua nghi$m ao" Kit hgp eac kit qua phan tich tham khung thep [11], khung thep SVP-22 vdi dp linh so bang phuong phap s i vdi eae kit qua hoat 240mm va kha nang chju lye 250 kN/khung thyc te, su dung phuong phap xu iy thing [10], d6, CO t h i xac dinh dugc tai hay kd, c6 t h i xac lap dugc cac m i i quan he gan ap lye tac dyng Idn khung ching theo quan he dung, hay dai didn duge cho mot vung nhit dinh ty Id giij'a ap lue va djeh chuyen Cu thd den Tu do, c6 thd c6 duac cae eg sd phyc vu thidt trang thai can bang c6 dugc ap lye hay tai trpng ke ban d i u , giai doan quy hoach, thiit k i cho cae duong 16 mdi dieu kidn tuong ty, tinh cho mpt met 16 la: - Khi f = 5, U(q) = 59 mm, qs = 250*59/240 = 62 ding thdi cOng cd dugc c^c gia tri gidi han cua djeh chuyin, eho phep dy bao v i kha nang tai kN/m KHCNM SO 11/2014* CNKT HAM LO Thong tin khoa hoc cong nghe mo biln dia chit hay pha huy co t h i xa hay khcng Cac kit qua nghien ciru eho thiy, can tang cuong su dung cae phuong phap so dk nghien ciru du bao cac qua trinh bien d l i ca hoc khoi da, cu the la giai doan thilt k l , d l du bao tai biln dja chit; c i n tang cuong dae, quan trac d l co t h i canh bao kha nang gap cac dieu kien dja chit bit thuo'ng, kha nang xay tai biln dia chat./ Tai lieu tham khao: [1] Nguyin Quang Phich: "Ca hoc da" Nha xuat ban Xay dung, Ha Npi 2007 [2] Nguyin Quang Phich: "Tai va ap ILIC dat da tac dung len ket cau cong trinh ngSm" Bai giang cao hoc nganh Xay dung cong trinh ngim va mo Dai hpc M6-Dia chit, 1999 [3] BaicnaujoB H B, KapTPSMn E.A MexaHMKa nPflxewiHbix coopyjKeHHti H KOHcrpyKUHti Kpeneii -MocKBa: Heflpa, 2012 -543 c [4] Nguyin Quang Phich; "Ca hoc da" Dai hpc M6-Dia chit 1992 [5] Rpcscience Inc (2006-2011), Phase2 Tutorial [6] Rocscience inc (2009), Roclab 1.0 Tutorial [7] Ngo Van Sy va nnk; "Nghien CLHU bo sung va tong hap cac chi tieu ca iy cua da cho cac mo Id thien, hSm Id vung Quang Ninh phijc vu cong tac khoan, no min, dieu khien ap life mo, bo mo" Bao cao tong kit d l tai NCKH Bp Cpng nghigp Ha Npi 10/9/2002 [8] "QuySt djnh Phe duyet Quy hoach phat then nganh Than Viet Nam den nam 2020, co xet trien vong den nam 2030" Thu tuo'ng chinh phu so 60/QD-TTg Ha Npi 2012 Tr - [9] "Tdng hap chi tieu l