Thong tin khoa hoc cong nghe m o /XAC OINH KiCH THI/OfC TOI UU GIUA HAI DUONG HAM GAN BE MAT DAT, CO TiNH DEN SIT THAY DOI H I N H DANG TIET DIEN DUONG HAM The determination of the distance between two transport tunnels is very important problem and has an influence on the stability calculation and tunnel designations However, nowadays In Vietnam, this problem has many disadvantages This paper introduces the study on the determination of optimal distance between two transport tunnels with the consideration for their shape changes based on the numerical method I.Datvdndl Vigc xdy du'ng cdc dudng ham ddi dang td xu hudng t i t y l u qud trinh xay dgng cae dudng him giao thdng ndi chung vd cdc dudng ham vgn tai edng nghigp khai thdc md ndi ridng Vige xay dgng dudng him ddi song song, cung vdi cdc dudng him noi ngang giCpa dudng him se ddp ung dugc nhu eau giao thdng tot han so vdi vige xdy dgng ham dan vdi ede Idn phuang tign vgn tai qua lgi ngugc chilu dudng him, trdnh tinh trgng ijn tdc him hogc ed sg e l ham thi phuang tign vgn tai ed t h i luu thdng sang dudng him bdn cgnh Trong qua trinh thilt k l thi cdng xdy dung cdc dudng him ddi thi vigc xae djnh kich thudc tdi uu eua tru bao vg giua h i m , hay Id khoang cdeh toi uu giO'a ham duge xem Id cd y nghTa Idn de dam bao tinh on djnh cao nhat cua dudng ham, eung nhu chilu ddi cdc dudng ham noi ngang giu'a ham Id ngdn nhat TS I R A N T U A N M I N H Truimg D^i hQC Md - Dja chat Ncs, NGUYEN VI£T D|NH Vi$n Khoa hQC Cdng ngh0 Mo - Vinacomin Bi§n t^p: TS Tnrong DCK DV Bdi bdo gidi thi$u vige xde djnh khoang cdch t i i uu giO'a dudng h i m , va cd tinh d i n vigc thay d l i hinh dgng tilt dign cua eae dudng him LTng suit biln dang xung quanh dudng hdm trdn dan Hign nay, bdi todn irng suit, bien dgng xung quanh dudng ham trdn dan dd cd rat nhieu cac tae gia d l cgp d i n , ed the k l d i n nhu Idi giai cua Kirsh, Lame, [7, 8] Tuy nhien, theo Terzaghi va Riehart (1995), md hinh bdi todn phang cho bdi todn mdi trudng khdng thuy tTnh cd the dugc the hign nhu hinh Theo Terzaghi vd Riehart (1995) eae phan U'ng suit vd biln dang d diem bat ky xung quanh dudng h i m trdn dan cd bdn kinh a vdi dp igc thing dipng tdc dung P dugc xae djnh bang ede bilu thirc sau: 0) (2) (3) (1 + - ^ 0 +4[l-i;')a)s lE,r ' 2E,r Hinh Hi thdng dwOng hdm song song thi/c td d Viit Nam KHCNM SO 5;21I15" CNKT HAM LO (4) M l[l-4cos2«-4(l-v')cos2« p(l 2E (5) Thong tin khoa hpc cong ngh# mo ddy: X - Hg s l dp Igc ngang; Ed - Md dun biln dgng cua dd; v - H$ s l Poisson cua d i t da c l n chO y ring, eae cdng thirc, ung suit phan bo khdng phg thupc vao md dun bien dgng Ed cua d i t da, mgt vdi Extensometer da duge lap ddt d l kiem tra m i i quan he giira ede djch chuyin U12 giu-a dilm 1, tgi vj tri r = a vd dilm tai vj tri r = rz (hinh 2) Chung ta thu dugc gid tri chuyin vj U12 nhu cdng thirc (5) Vd theo eae edng thirc (1), (2) va (3), d khoang each r = (4-5)a, irng suit se chuyin ve trgng thai u'ng suit nguyen sinh p J* V V * # » 4- * * Hinh Phin bd O-ng suit xung quanh dwdng hdm tidt diin trdn, mOi trudng thuy tfnh, vOI bai toin bidn dang phing (9) Hinh Tip tmng Ovg sudt xung quanh dudng hdm d^ng trdn mOi trudng khOng phii li thuy &nh P(, a'\ Neu gia thilt dudng h i m ed dp Igc ben Id p thi Idi giai bo sung trudng hgp ndy dugc vilt dudi dgng nhu sau: CT^ + cr^ = 2P a' (\ + v)[P-p,)a (6) a' ^i = -Pi 7 (i + vWi (7) (8) Dieu cd nghTa Id irng suit tilp tuyln la irng suit keo thuc t l Trong tnj-dng hgp ddc bi^t mdi trudng Id thuy tTnh, Idi giai cuoi eiing dugc t h i hign nhu hinh Kit qua ch) rdng tong cua img suit tilp tuyen vd hudng tam bang lan irng suit thing dung d bit k^ ddu khli da vd eae thdnh phin irng suit, chuyin vi dugc vilt dudi dang sau: (10) (11) (12) Cac eong thirc o tren thu dyoc eho trang thai irng suat phang (irng suat dpc thep true tju'crng him la bang khong) Loi giai se du'pe hipu chmh chut it cho cacdjch chuyen tru-ong hpp bai toan bien dang phing nho thay the he so Poisson cae cong thirc tren (Jaeger va Cook, 1969) (13) 1-v' (14) Cae cong thirc (5), (8) va (12) khong thay a6i KHCNM S 5/2015* CNKT HAM L Th6ng tin khoa hoc cong nghe mo truong hpp bai toan bien dang phang NhOng quy luat eua cac bien dang co t h i de dang tim dupe bang viec so sanh eae bien dang voi mot luy thCra bje ba tdi eae irng suat ehinh cho bai irng suit phang (02 = 0) va tru'o'ng hpp bien dang phang (e2 = hay 02 = v{ai + 03) Thoi gian g i n day, Carranza va Fairhurst (2000) da giai thlpu cong thii'c kinh nghipm sau cho vipc xac djnh dieh ehuyen huong t^m ur tai mOt khoang each x phia tru'dc guong dudng ham (x 0) vi phia sau guong ham (x > 0), hudng tdi cua him trong-tcwdng hpp dudng ham tron, di4u ki#n i r n g ^ a t thuy tmh: + e'- dpng D = 0,3; Ty s6 img suit nam ngang/thing dirng 03/01 = 1; Bp sau d$t dudng him H = 25m; Chilu rpng (dudng kinh) dudng h i m B (D) = 10m Bang phan mlm s l Examine 2D ehiing ta c i t h i thilt Up m l hinh phan tich va thu su phSn b l ung suat xung quanh cae dudng him, kit qua duiQic the hipn nhu hinh Bing each lam tuang tu ehiing ta thu dupc phan b l ehuyin vj ting t h i xung quanh dudng him vdi hinh dpng khic Examine 2D, kit qua dupc the hipn nhu hinh Tip kit qua phan tieh bang Examine 2D, vol eae khoang each khae giua dudng him (15) = 0.31, tpi vi tri X = (guong him) = 1.0, tpi vj tri X = 00 = tai X - > - 00 Djch chuyin hudng tam Um = Ua (vdi pi = (trong eong thirc (12)) Phan tich s6 xac djnh khoang each tdi uu giira cac dirvng h i m cd chu y d i n SLF thay ddi hinh d^ng etrimg h i m Ngay nay, vdi su phat triln cua cong nghp tin hpe va khoa hpe cong nghp, phuong phap s6 cang dupc irng dung rpng rai hon trpng qui trinh giai c4c bai toan dia ky thuat MOt nhCrng vin d l m i CCT hpc da quan tSm la quy luat biln doi CO hpc (su thay doi eae g\i trj irng suit - biln dang) xung quanh eae khoang tring ngam sau khai dao [1,2,3,4, 5] Bilt dupe quy luat thay doi se giup eho ngudi thiet k l kit c l u ching giu' cung nhu giu" on djnh dudng ham mot cich eo hi$u qua B l phSn tieh I n djnh va xae djnh khoang each tii uu giu'a dudng him khong ching, d day su' dung phan mlm s l Examine 2D, tren ca sd phuang phap phin tu' bien [6, 9] Cg the, cac thong s l diu vao cho bai toan plisn tich dupc t h i hipn nhu sau: Trpng lupng t h i tich y = 0,02MN/m=; BO bin nen an = 5Mpa; Mo dun biln d^ng Em = SOOMPa; Hp s l Poisson n = 0,32.Ti6u ehuin sir dgng Hpek-Brown, vdi cio thing s l GS! = 22; Hing so vat lipu m„ = 6; Hp so chin KHCNM S6 m i ' CNKT HAM L c) Suing him dang vdm ming ngua Hinh Phin bi img suit thing dOng xung quanh duimg him khing (tiing, bing phin Sch Examine 3D tuang img vdi eao hinh dang khic d tren, se xae djnh dupe cae trj s l irng suit, chuyin vj cija d i t d i d khu vuc nlm giu-a dudng him, tip do, se thiet lap duac cac quy luat biln doi ung suit va chuyen vj ciia d i t d i giu'a dudng him TrOn hinh the hien phin b l irng suit v i chuyen v| giua dudng h i m , vdi tilt dipn him dpng hinh tron (a) v i vom mong ngua (b) B l xac djnh duac khoing each t i i uu giua Tongc huyIn vj gltta dudng hin Thang tin khoa hoc cong nghg mo ! ! ! ! ! • ! — Khodng cdch gi&a dudng hdm >auL Dm- t *jr • nn» ^ DHT' — — ) Him tiit diin tnin i.i/i/i/;/: ffrjT\ /r-I fr-f, f-r \ %^\/y\/\ \ , - _ ^_" i 1 1 1 IF l^ ID K 1D Ij- Khoang cdch giO'a dudng ham b) D^ng tidt didn hinh mdng ngi/a Hinh Ong suit vi chuydn vi cua dit di xung quanh dwdng him, vdi khoang cich khic dudng ham, phai thilt lap duge moi quan he giua irng suit vd chuyen vj cua d i t da d dilm giua cua dudng ham, so vdi khoang edeh giira chung, gia tn Crng suit, bien dang d dilm ndy ve vdl trang thdi cdn bang tg nhien, se xdc djnh MBraPli^V dugc khoang cdch t i i uu giO'a dudng him ^^"^T Tren ca sd kit qua phan tich bang Examine 2D, ed the thilt lap dugc moi quan hg giua irng suit va chuyin vi cua dat da d diem nam giOa dudng him (xem hinh 7) Quan sat kit qua tren hinh va ehung ta 1', t.' ' i ^ ^ ^ • ^ ^ ' thiy ring ndo irng suit gan v l gia tn irng suit nguyen sinh a = yH = 0,02.25 = 0,5l\/IPa vd c) Quing him dang vim ming ngua chuyen vi cua dat dd d dilm gii>a khoang each Hinh SflhSnbi Ung suit, ting chuyin vjxung quanh 2 dudng him tigm cgn thi ehung ta thu dugc dudng him khing ching bing phin tkh Examine 2D khoanp each t i i uu eho dudng ham b) Dudng him tudng thing, vdm tim fe KHCNM S 5/2015* CNKT HAM L Thong tin khoa hoc cong nghe m o la 20-25m (tuong u'ng - Iln bin kinh dudng ham), ham vdm mong ngua v i ham tudng thing vom t i m la 30-35m (tuang Crng - i l n m|t Q nl>a chilu rpng n i n him) rs^' ' c Thong thudng viing anh hudng cOa cong tio khai d i o dudng him vdi dudng him trin tip c '•'- T ^ T"^"—'-t-i—^ _ I lan bin kinh dudng h i m , dilu niy thoa man •xa £ vdi ly thuylt dudng h i m tron Tuy nhien, d '4Q bai toin nay, su thay d l i hinh dang eOng nhu CO hinh vdm mong ngua va vdm t i m tudng c • [ ]'• I thing, kha nang tu I n djnh kem han vdi him Khoang cich giCra dudng ham tron, nen khoang each giu'a him se phii ting len vdi khoang tip d i n i l n mpt nii'a chilu a) (fng suit thing dirng rpng him Bang md phong tren, vipc tinh toan se trd len nhanh hon, dua them i p lue kit clu ching giu' vao ben dudng h i m cung e l t h i xic dinh dupe khoing cich vdi cie dudng him CO kit cau ching g\is.l Tai lieu tham khao [5] Nguyin Quang Phich, Ca hgc di, NXB Xay dung H i Npi, 2007 [1] Nghiem HiJu Hanh, Cahpc di, NXB Xay dung Ha Npi, 2004 [2] Vo Trpng Hung, Phiing Mpnh Bic, Cohqc Khoang cich giCra dudng ham di irng dung xay di/ng cdng trinh ngim va khai thic mo, NXBKHKT Ha Npi, 2008 b) Chuyin vi ting thi [6] Nguyen Quang Phich v i nnk, Nghiin ciru Hinh Mil quan hi gida irng suit, chuyin vi ting img dung mgt so phuxyng phip s6 tinh toin thi cOa dit di d vl tri trung tim khoing giira cong trinh ngam Be tai eip b l ma s l B2005-36dudng him vdl khoing cich tuong ung cua nd 88Te, Ha N|i, 2006 Trong trudng hop dudng him dang tron thi [3] Trin Tuan Minh, Nghiin ciru cic qui trinh khoang cich niy l i 20-25m, dang mdng ngua, bien doi co hgc khoi dat di cd chu y den 30-35m, tudng thing, vdm tam, gia tri eua no cic tham so, luin van thae sy ky thuat, H i Npi eung dao dong 30-35m [4] Tran Tuan Minh, Bd Quang Tuin Phin K i t luan tich Sir bien doi ciJa vung bien dang deo xung Trong vipe xay dung c i c dudng him giao quanh cic duung him co xem xit din yiu thong, k l ca nginh khai thae mo, dudng to img suit bang chuong trinh Examine 2D, Hpi him gin thudng dupe ap dung Vipe xie nghi KHKT mp toan quIc i l n Vnii 19 thing djnh kheang cich t i i uu giu'a dudng him ec y 11/2008, tuyln tap bao c i o H|i khoa hpe v i nghTa rit Idn, l i m giam ehi phi xay dung eung ccng nghp mo Vipt Nam, tr 242 - 246 nhu vpn hinh dudng him Bing Examine 2D [7] B.H.G Brady and E.TBrown (2004), Rock Chung ta co t h i x i c dinh iuqc su phin bo irng mectianics for underground mining, Dordecht suit, ehuyin vj cua dat da cung nhu vting anh [8] Dimitrios Kolymbas (2005), Tunnelling hudng xung quanh dudng him and tunnel mechanics, Springer - Verlag Berlin Trudng hpp dudng him tron, trpng dilu Heudelberg Germany ki0n dat d i eg t h i nhu d tren, khpang cich niy [9] VKVKW.rocscience.eom 1- ' a,^ : - — r — _; " KHCNM S6 5/2015* CNKT H.AM LO ... tSm la quy luat biln doi CO hpc (su thay doi eae g\i trj irng suit - biln dang) xung quanh eae khoang tring ngam sau khai dao [1,2,3,4, 5] Bilt dupe quy luat thay doi se giup eho ngudi thiet k... eho trang thai irng suat phang (irng suat dpc thep true tju''crng him la bang khong) Loi giai se du''pe hipu chmh chut it cho cacdjch chuyen tru-ong hpp bai toan bien dang phing nho thay the he... tio khai d i o dudng him vdi dudng him trin tip c ''•''- T ^ T"^"—''-t-i—^ _ I lan bin kinh dudng h i m , dilu niy thoa man •xa £ vdi ly thuylt dudng h i m tron Tuy nhien, d ''4Q bai toin nay, su thay