Thong tin khoa hoc c6ng nghe mo "W '''' VAN DE DjCH CHUYEN, BIEN DANG SUT LUN DAT DA KHI KHAI T H A C THAN VA CAC YEU TO ANH HirCflNC Recently, underground coal mining activities in Quang Ninh coal basin[.]
Thong tin khoa hoc c6ng nghe mo "W ' VAN DE DjCH CHUYEN, BIEN DANG SUT LUN DAT DA KHI KHAI T H A C THAN VA C A C YEU T O ANH HirCflNC Recently, underground coal mining activities in Quang Ninh coal basin have shown that, the rock displacement, defonnation and subsidence have impacted on the mining and construction buildings Therefore, it is neccesary to carry out research on displacement control for ensuring the safety of the constructions I.Datvdndd Dich chuyen, sut li!in d i t da Id mdt he qua tat y|g cua qua trinh khai thdc mo h i m 16, muc dp c6 thi nho, cue bp hogc phdt triln tren khu vye rpng Idn, no co the xay lap tuc hoac nhilu ndm sau khai thae xong Trong nhung nam gin day, vdi vigc md rdng thj hda vd gia tang moi quan tdm ve moi trudng, moi sinh nen khdng t h i bo qua vigc nghien CLPU, danh gid qud trinh hau qua cua sgt lun Ky thuat danh gia, tinh todn sgt lun khong nhOng ddi hoi sy nghien cuu djch chuyen d i t dd, d u true dja chit vd dja eo hpc (ca d i t vd eo hoe dd), md edn b a c gIm kiln thue v l khao sdt, khai thdc khodng san vd lu^t tdi san, phuong phdp vd ky thudt khai thdc, thu tgc xdy dyng, edng nghg truyln thong, khoa hpc nong nghlgp, thuy van va dia chit thuy vdn, quy hogch thj vd eae v i n d l ve kinh t l xd h$i khde TS Le VAN CONG KS LUU C O N G N A M KS PHI VAN LONG Vidn Khoa hoc Cdng nghd Afd - Vinacomin Bien tip: TS Ph^m Minh Ddc tring va cac dilu kien dja chit cdng trinh, thuy van khae Theo thdi gian, khoang tring to, rpng ra, dan d i n sy mat on djnh Dilu dan din cdc Idp dat dd di chuyin vdo khoang tring Din din, nhung chuyin dpng phat triln len din b l mgt, bieu hign thdnh mot vung sgt lun Sgt lun mo, do, cd the duge djnh nghTa la djch chuyin cua d i t dd xay sy sgp d l eua cde tdp d i t da nam phia tren ede via khai thdc vao khoang trong md Sgt lun be mat thudng theo chieu djch chuyen thing dung vd nim ngang Liin be mat co the bieu hien d ba hinh thifc chinh: cae v i t nirt, nut ne, hoac dirt vd; cdc 16 hoac h i sgt vd d dgng mdng sgt hogc vung trung xulng Khi dien tich b l mat phan sgp lun Id tuong d l i nho, vung ndy duge gpi Id mpt ho hogc 16 liin N6i chung, hign tugng thudng Id khai thae dang buIng cpt d mice dp via nong gay O'Anh, thudt ngi> 16 mieng, Ing khdi hoae Ing Tgi vung than Quang Ninh, qua thdi gian khai thdc him 16 da eho thay, cdc v i n d l sut liin, djch thudng duge sir dgng de mo ta hien tugng ndy chuyin, biin dgng dat dd da anh hudng den cdc Theo thdi gian, eae h i c6 t h i md rpng vd kit cong trinh khai thdc vd xdy dyng Do vay, vdn de hgp Igi d l hinh thdnh cac viing Idn hon gpi Id nghien cuu, dilu khiln djch dpng dam bao an hdo Dp sau cua h i liin thudng Id co gidi hgn, todn cho cdc eong trinh d n dugc xuc tiin dap nhung thudng toi da Id 10 den 15 lln chilu ddy ung cde eac thyc tien san xuit vi'a khai thdc Cg c h i tao djch chuyen, b i i n dang, sgt Khi khoang tring mo co kieh thudc Idn hon lun khai thae than khai thae 16 chg dai hoac sup d l khai thdc 2.1 Phat trien djch chuyen, bien dang, sut hit cac trg bao vg, cdc ldp dat da sup roi vdo cdc dudng 16 vdi so lugng Idn Qud trinh ndy lOn Khi mgt khoang tring dugc tgo dudi Idng tilp tgc cho din chieu cao dat khoang din dit, khai thdc khodng san hoac vi ly ndo lan chieu day via khai thdc Khi khoang sgt liin chira day dat dd vd, cdc khde, ung suit Idp d i t da xung quanh khodng tring bj thay doi, phan b l Igi Nhirng manh vd tgo khoi chong 6a cho eae Idp Idn thay d l i ung suit tgo bien dgng vd dieh can phia tren (hinh 1) Khi cac ldp dat da lun chuyin cdc Idp dit da, mue dp phg thupc vac hode vong, tach Idp cd t h i xay theo xu hudng d | Idn cudng dp ung suit, kich thudc khoang Idp phia dudi lun nhilu hon Idp phia tren Nhin KHCNM S6 9/2014' CNKT HAM LO Thong tin khoa hpc cong nghe mo Viatiian Bung nen Hinh Su sut lun, dich chuydn cac Idp dit da phia tren via khai thic ehung, cae Idp da cd dp benvd tinh lien tuc ^,_^ eao, chiing vong xulng chLc khong bj phd vd va tao mpt viing sgt liin dgng mang hoac dang dTa tren b l mat Ddy Id ddc dilm phi biin bao gom mot khu vye Idn hon h i sgt, vd dugc gpi la mdng hoae vdng liin Mang lun cd t h i xay khai thdc d dp sdu b i t ky Cdc djch chuyen cua khIi dd xung quanh cong trinh dugc mo ta hinh Hudng ehuyin dpng cua khIi da khong chi theo chilu thing difng xuong ma cdn ca theo chieu ngang vd tai mgt so dilm Id theo chilu hudng len phia tren Nlu khai thae mpt diem Hinh Sa mo ta su djch chuydn dat di khai nhat, dilm P d mire ndo se anh hudng d i n thic sut lun giy mpt khu vue c6 dang tr6n tren b l mat, dugc xdc djnh bang day cua mpt hinh non ngugc vdi dilm bj anh hudng bdi khai thdc md noi chung la Idn P la dinh va goc gidi han bang nua g6e hinh hon so vdi dien tich vung khai thae Do d6, goc n6n Neu hinh non ndy 6wcfc lat lai thing dirng, nghieng theo ehieu thing dirng d canh cua vung do, viec khai thdc b i t ky phin nao cua ddy khai thae va diem khdng chuyen thing dirng d se anh hudng d i n dinh liin P (hinh 3) Do do, cgnh cua mdng duoc gpi la goc gidi hgn hogc khu vyc hinh tron duoc gpi Id khu vyc anh goc liin 2.2 Sy djch chuyen cua diecmg cong lun hudng Dilu cho thdy dudng kinh cua khu Khi sut lun xay ra, co sy dich chuyen cua cac vyc anh hudng dugc hinh thdnh bdng gia tri 2D * tanga , do, D Id chilu sau cua via so vdi dilm b l mat ve phia trung tdm eua viing khai thdc Gid th djch chuyin thing difng la Idn nhit be mat vd "a" la goc gidi han Dudng kinh ndy eung xac dinh chilu rong tdi d trung tam c6n djch chuyen ngang Id it nhit d hgn ciia khai thdc, la chieu rpng t i i thieu khai trung tam vd cde canh cua mang, hoae gan cdc thae trudc liin t i i da xay tai trung tam canh eua khu vyc khai thdc Do djch chuyin mdng lun Nlu chilu rpng khai thae nho hon gia ngang khong phdn b l deu dpc theo mat cat th tdi han, thi duoc gpi la chieu rong dudi tdi han ngang cua 16 chg NhCfng bien dgng co xu va gia tri sut liin xay se nho hon so vdi gia trj hudng keo dan b l mat gan cgnh cua mang vd lun t i i da Nlu chilu rpng Idn hon gid tri tdi han, day vao ben ranh gidi khu vye khai thdc phan trung tdm cua mdng se dat lun t i i da va Ca biin dgng nen vd keo d i u khong xuat hign d vung sut liin ddy phang se dugc hinh thanh, Nlu trung tdm cua mdng liin trudng hgp vung via than tuong d l i blng phing, gdn nhu nam khai thae co chilu rpng tdi hgn vd tren tdi han ngang, cdc ldp dat da phu vd sap lun tao Theo tiin dp guong 16 chg, cdc khu vyc biin mgt vung sut d l hoac mang lun Dien tich b l mat dgng nen va keo theo phuong ngang eung di '\'^^xrtn//j \\\^\'!/h KIICNM s o 9/2014* CNKT HAM LO Thdng tin khoa hpc cong nghe mo Hinh Sa dd du bio vOng inh hudng lun khai thdc md chuyin dpe theo guong Id chg (hinh 4) Do do, day cDng dugc gpi Id biin dgng dl chuyen Cdc ylu td anh hirdng din djch chuyin, biin dgng, s^t lun md Nhilu ylu t l dja chit vd khai thdc anh hudng din djch chuyen, biin dgng, sgt liin, eg the nhu sau: Chiiu diy via cd inh huang tdi dich chuyen, biin d^ng, si^t lOn: Via khai thdc edng day, mifc d | sgt liin b l m|t cdng Idn Trong mpt s i trudng hgp, todn bp via c6 the khong duge khai thdc hit hode d l lgi trg bao vg hoae than co t h i dugc de Igi vl ly nao khde Vi thi, ehieu ddy via khai thdc d n phai dugc xem xet Khi khai thdc via ddy, dO manh (ty Ig chilu cao/chieu rpng) eua trg bdo vg thudng cao n§n d l bi phd huy hon T$p via: Trong trudng hop khai thdc tap via, sy gdp co t h i dugc bat dau tir bat ky mot mire ndo, do, Idm tang kha nang eua dich chuyin, lun, cdc Idp liin k l bi tac dpng Dilu ndy d0c bigt dung khai thae trude mot via nim phia trdn (a) suphat thin cua biin d^ng (b) Hif&ng tiin cOa duang cong biin dang Hinh Si/phit tridn cOa phdu lun vi biin d$ng theo tidn dd Id cha Goc ddc cija via: Khi khai thdc cdc via than die, mang lun dugc hinh thdnh mpt edeh khdng doi xii-ng, n6 nghieng ve phia chilu die; goc gidi han Idn hon gdc d i e viing khai thdc Bien dgng cung nho hon theo hudng die Trg bao vg khai thdc via d i e cung co xu hudng it on djnh hon so vdi via thoai Dp bdn vQ-ng cIJa vach va tru via Do liin lan truyln tif eac muc khai thdc, dgc diem cua vdeh vd trg via Id rat quan trong vigc khdi tgo djch chuyen liin Tang set mIm, dgc bigt d l bj suy ylu dp am, tao sy phd vd trg bao vg hogc bung nIn Vdeh ylu, nhu da philn set, bpt kit va da vol, gay mire dp sgp mgnh Ldp vdeh ben vu'ng co xu hudng ching giu cdc Idp dit dd phia tren lau hon vd do lam ehdm Igi qua trinh djch chuyen, sgt liin Ngoai ra, ehiing dut vd se chilm mpt khoi lugng Idn hon so vdi eac Idp ylu Lop dat da phu: Cac Idp dd eifng virng, khoe tao khIi phia tren via khai thdc c6 xu hudng chong dd Idp d i t da phu mot giai dogn dai Chiiu sdu via: Theo trudng phai v l dp lyc vd tri hodn sy xuat hien cua liin khdng phg thupc chieu sau, mpt v6m pha huy Dja chdt gan be mat: Cdc loai dat dd khong dugc hinh thdnh phia tren eac dudng 16, lam ngan eh$n sy sgt tun b l mgt Trong nhung ndm gan day, vi>ng chdc g i n b l mat e6 xu hudng chju tdc dilu ndy da timg budc bj thay dli Ld khoang dpng liin Ddt dd it dong nhat vd ddng hudng thdi gian tip khai thdc din edc hieu irng lun hon so vdi cdc Idp eo ban vd thudng co tinh dugc quan sdt thiy d b l m|t bj k6o ddi, md ting chit khong nhat qudn gid trj lun xuit hign khong thay doi; ed nghTa liin Cdc vit nirt budc dau co t h i hinh thdnh d|c l$p vdi dO sdu (Orchard, 1964) Dp sdu lun Idp day 15m tif b l mgt Sau do, co t h i dugc thudng kh6ng vugt qud gidi hgn nhit dinh Chen lip bdi cdc bien dang deo hogc vgt ligu vdn KHCNM s o 9/2014* CSK P HAM LO w Thong tin khoa hoc cong nghe mo b l mat hoac dudi idng dat (trong cae ting ng^m nudc) Khu vyc thdp cd t h i bj nggp lut Dd eo t h i bj suy y l u bdi bao hoa nude Dgng xdi mdn cd t h i thay doi va viing nui da vdi, hang dpng hoac cac khu vyc nui da vdi cd the dugc tao mdt khpang thdi gian Nudc mua dugc tich luy tgi be mat hogc nudc tip dudng I n g b| rd ri, nudc cd t h i thim qua dat den cae nirt ne va eac v i t nirt da g l c va cuoi cung vdo eac dudng Id Nhirng tdc ddng xdi mdn gay s y pha huy /Wtre nuoc: Nude Idm giam dp b i n vd dp Nui ne, gian doan dja chit: Sy t i n tai cua cirng cua tru bao ve va vdeh try via rd ret Thay phay pha, n i p uln vd nhirng d u true tuong ty d l i djnh ky dp I m md, thiic d i y sy suy khIi da c6 t h i Idm tang mifC dp djch giam tat ea cdc phan dp ben Ldp dit da chuyin, lun Khai thae khodng san lam anh mIm d§ bj phd huy, d i n den sy mat I n ^nh vd hudng tdi sy can bang cua eac lyc cae ldp sgt liin Ddng chay qua v i t nirt gay dp lyc ro d i t dd vd e6 the gdy chuyin dpng dgc theo ri, gay nguy hilm eho s y I n djnh cua khoi dd mat phay phd, d l trugt, gay liin hode trdi Dien tich khai thae: Khi chilu rdng vugt qua len b l mat, Nhu'ng dnh hudng eua cde thong s i gid trj tdi hgn dpc theo ca hai true ngang vd dpc khde c6 the bo qua vung co dilu kien b i t se tgo dp liin toi da Dilu ndy dac bigt quan Igi dja chit Nirt vd ty nhien cung co anh hudng trpng nlu Idp dat da ben vung cd mat tang din djch chuyin, lun b l mat, nhung m l i lien he dat dd phu tao cau n i l I n djnh glij'a cac 16 chg van cdn chua duoc d l cap, nghien eifu va giam liin ehieu rpng 16 chg nhd hgn gid trj Cfng suit nguyen sinh: CCng suit nam ngang tdi han, mac dii chilu dai 16 chg cd t h i Idn hgn cao, CO xu hudng han c h i sut lun b l mat hinh Phuang phap khai thae: Logi liin ban dau Id v6m phd huy trongkhoi da Chilu cao vom h i hoae mdng ed the xay ra, phu thugc vao vigc phd huy vd sy I n dinh rat nhgy cam vdi ty s i SU' dgng phuong phdp khai thdc budng cdt hay ifng suit thing dung/ndm ngang Vom ch|u irng 16 chg ddi Vdi phuong phdp buIng cdt, cd suit cao c6 the bj phd huy manh Mdt I n djnh sy sap cua cac try bao ve ed the ddn den viec vdeh vd biing nen, ifng sudt nam ngang cao tao eac hao hoac lim vdng b l mat Cdc djch vd phuong chieu cua chung gay d n phai chuyin va bien dang tren mdt khoang each ngan dugc chii y den thilt k l cae mo than la rat quan trpng chiing bat ddu xuat hien tren Muc dQ khau via: Ty le khdu via thap hon co b l mat Khi khai thdc bang phuong phap Id chg xu hudng lam giam djch chuyin, lun Lfng suit ddi thi gan nhu lap tire djch chuyin, liin se cue bp thiic day su pha huy va cac khu vyc vach xay Khai thdc bang phugng phap Id chg ddi id qua rpng giu'a cdc tru bao ve Djch ehuyin, liin ke ciing mpt via hoac cac Id chg ching bien dang, sut liin dat da khai thdc than Id len cde via khde nhau, cd t h i dugc hdm theo thdi gian, phg thuoc vdo t i e dp lan sCf dung de vd hieu hda cac biin dgng nen va truyln djch ddng len phia tren keo vd dd bao ve duge k i t d u tren b l mgt Dja hinh be mat: Dat da sudn d i e ed xu Tuy nhien, phuong phdp ndy la khdng de ddng hudng tgo djch chuyin di xulng lyc ap dung vd duge gidi hgn su' dung theo cdc yeu Biin dang keo ed t h i tang them tgi cac dinh doi d u kinh t l , xa hpi vd giam di tai cdc thung lung Tac ddng be mat Toe tien gwang Id cho: Djch chuyin, lun vi vdy bi anh hudng be mat theo sau guong Id chg nd tiin theo Nudc ngam: Bien dang eua cdc Idp xung cac luong khiu N l u t i c khiu than thay dli quanh khu vyc khai thae cd t h i lam thay d l i dp mdt edeh rd rgt, cae biin dang cung thay dli doc thodt nudc, dan d i n sy hinh ho chifa Theo kinh nghiem, toe dp tien guong nhanh Id chuyen d i n nudc ngdm Ddi khi, ddng chay CO the Idm eho cdc vet nirt phat triln va tgo thdnh nhu'ng ranh Idn Cau triic vd viing tai nguyen tdi tgo do bj anh hudng b i t Igi Cdc phan cua Idp d i t da phu id rdt quan trpng; neu vgt lieu la eat mjn co chira luong Idn nudc, no c6 t h i chay vdo v i t nirt ne va cac hang dpng ngam Ben cgnh do, nudc tich tu lai cdc mo bj bo hoang co the thdm trd len vdo ldp d i t da phia tren, thong qua vet nirt ty nhien va edc v i t nirt da, Idm tang kha nang sgp d l cua dat dd KHCNM SO 9/2014* CNKT HAM LO Thdng tin khoa hoc cdng nghe m o tit nhit [2] Chen lap vdng khai thdc: Chen Id, l i p di mgt phin hogc hodn toan khoang tring vung khai thdc lam giam djch chuyen, liin Lugng sgt liin xay phg thupc vdo logi vd mire dd chen l i p dugc thyc hign S$p theo thoi gian: Lugng liin dugc quan trdc la mdt ham theo thdi gian Theo phuong phdp khai thdc buIng cpt, khdng ed tde dgng djch chuyin, liin be mat dugc ghi nhdn sau mpt thdi gian khai thae dugc hodn tat, eho din nhCrng trg bao v§ bj hu hdng hogc phd vd Trong phuong phdp Id chg ddi, be mat cd t h i bat dau bj vdng xuong gan nhu Idp tifc sau guong Id di qua Tuy nhien, trudng hgp ddt da Idp phii tgo khil thi ed the tri hoan qud trinh Vdi Id chg ddi, dieh chuyen be mat xay hodn todn vdng mdt vdi nam, nhung tai bao vg edn Igi vdn nguyen vgn de ching gitf, thi cd the mat hdng thdp ky Khi sif dgng phuong phdp khai thdc buIng cdt vdi vigc loai bd cac tru bdo v$ cd t h i tgo higu ifng djch chuyin, liin b l mdt tuong tu nhu khai thdc Id chg ddi, vdi mire dp tuong tu phg thugc vdo lugng than de lgi Idm kit d u ching giCf Dgc diem cau true: MifC dp thigt hgi d l i vdi cdc kit d u phg thupc vdo logi d u triic vd kich thudc, hinh ddng, tuoi thp, thiet ke nIn mdng, v^t ligu va ky thuat xay dyng, tieu chuin ve bao tri vd su-a chija vd muc dich su dgng [3], Tai trpng phu xay dyng cd t h i gdy sy nen chat dit, tgo sy mit I n dmh Cau triic cd chilu eao Idn khdng t h i chiu dugc dp nghieng nhilu, chdt lugng xay dyng kem hogc ede tda nha cu cd t h i de dang bj hu hgi gay bdi lun Higu Cpng thdi gian Thdi gian liin khai thae md bao gom hai giai dogn: (1) hogt dgng va (2) lun du Hoat ddng liin d l egp din tat ca cdc djch chuyen xay ding thdi vdi cdc hogt dpng khai thae md, lun du la mdt phan cua sy biin dgng be mat xay sau dd difng khai thdc (hogc trudng hgp khai thae Id chg ddi, sau khai thdc dd dat din chilu rpng tdi hgn eua nd) Thdi gian lun du Id dgc bigt quan trpng theo quan dilm eua phd huy d u triic be mgt cung nhu tir gdc dd phdp 19 Thdi gian keo ddi lun b l mdt thay doi ddng ke •w theo phuong phdp khai thdc duge sir dgng Ld chg ddi gay lun nhanh chdng, bat dau gan nhu ldp tire sau khiu Id chg ban diu Vdi he thing khai thdc buIng cdt, xuat hien ehu ylu cua liin b l mat ed t h i bj tri hodn nhieu thgp ky cho d i n edc trg bao vg ching giu- da x l u di ddng ke hogc bj syp Thdi gian thue t l phy thudc vdo mgt so y l u t l nhu dp ben eiia than, da vdeh vd trg via; mifC dp nirt vd; sy hign dign cua nudc; ehieu sau khai thae; kieh thudc trg bao ve; vd ty le phan tram khai thdc via Do dd, dy bdo ndo hoac bao nhieu phd huy ed t h i xay Id dilu khd khan Khai thdc Id chg ddi: Thdi gian djch chuyin sgt lun du tren lulng khiu Id chg ddi Id tuong d l i ngan, thudng thay doi tir mdt vdi tuan va khoang 10 nam Hon nija, dp Idn cua cdc djch chuyin hilm vuot qua 10% tong lun K i t luan Djch chuyen, bien dgng sgt liin dit dd khai thae than Id qua trinh phirc tgp phg thudc vdo nhieu yeu t l Nhifng hilu hilt, ddnh gid khdch quan ve qua trinh ndy cho phep dllu khien vd han c h i cac tdc dpng cua chiing din moi trudng vd cac eong trinh b l mat Tren co sd phdn tich eo che tgo sy djch chuyin, blln dgng, sut liin dit dd khai thae than, phdn tich cdc yeu to anh hudng den qua trinh, cdc thdng so djch chuyin kit hgp cde phuong phap tinh todn phu hgp d l xac djnh dung hinh dgng, kich thudc, thdi gian xay djch chuyin, blln dang d i t da bao vg cdc cdng trinh khai thdc vd mdi trudng xung quanh Tai lieu tham khao: I B a o cao tong kit de tai: "Nghien ciru xac dinh cac thong so dich chuyen, bien d^ng dat da khai thae via day bing phuang phap ham Id tren md hinh vat lieu tuang duon^' - Vign Khoa hoe Cdng nghe Md-2012 Mining engineering handbook - Daryl Kay -2010 The occurrence, measurement, mechanics, prediction, and control of subsidence - UNESCO Working Group on Land Subsidence - Figueroa Vega; Ivan Johnson- 1975, Prediction of Surface Subsidence and Its Monitoring - M Venkat Ramana Rao - 2010 KHCNM S69 2014* ( NKT HAM LO ... ehieu ddy via khai thdc d n phai dugc xem xet Khi khai thdc via ddy, dO manh (ty Ig chilu cao/chieu rpng) eua trg bdo vg thudng cao n§n d l bi phd huy hon T$p via: Trong trudng hop khai thdc tap... cha Goc ddc cija via: Khi khai thdc cdc via than die, mang lun dugc hinh thdnh mpt edeh khdng doi xii-ng, n6 nghieng ve phia chilu die; goc gidi han Idn hon gdc d i e viing khai thdc Bien dgng... guong Id chg nd tiin theo Nudc ngam: Bien dang eua cdc Idp xung cac luong khiu N l u t i c khiu than thay dli quanh khu vyc khai thae cd t h i lam thay d l i dp mdt edeh rd rgt, cae biin dang cung