收敛约束法中隧道开挖面空间效应方法比较-张常光

375Vol.37No.520165RockandSoilMechanicsMay20162014-08-05No.41202191No.20142BAB206001No.GJJ151117ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina(41202191),theNaturalScienceFoundationofJiangxiProvince(20142BAB206001)andtheScienceandTechnologyProgramforJiangxiEducationalCommittee(GJJ151117).1982E-mail:[e-mail]10.16285/j.rsm.2016.05.02512,31.7100612.3300993.3300992TN(09)VD(09)2TN(09)VD(09)TU452A10007598(2016)05141708Comparisonsofspatial-effectapproachesfortunnelexcavationusingconvergence-confinementmethodZHANGChang-guang1,ZENGKai-hua2,3(1.SchoolofCivilEngineering,Chang’anUniversity,Xi’an,Shaanxi710061,China;2.SchoolofCivilEngineeringandArchitecture,NanchangInstituteofTechnology,Nanchang,Jiangxi330099,China;3.JiangxiProvincialEngineeringResearchCenteroftheSpecialReinforcementandSafetyMonitoringTechnologyinHydraulic&CivilEngineering,NanchangInstituteofTechnology,Nanchang,Jiangxi330099,China)Abstract:Aproperspatialeffectapproachofexcavationfaceisthepremisetomakefulluseoftheself-bearingcapacityofrockmass.Inthisstudy,tworepresentativespatialeffectapproachesofexcavationface,i.e.,thesupportstresscoefficientapproachofT-N(09)andthedisplacementreleasecoefficientapproachofV-D(09),arecomparedqualitativelyandquantitativelyabouttheirsources,influencingfactors,scopesofapplication,performancesofspatialeffectanddifferencesofconvergence-confinementandsoon.Itisfoundthatthetwospatialeffectapproachesofexcavationfacearebothreadilycombinedwithgroundresponsecurvetopracticalengineeringapplicationsandhavegoodconsistencyinsomerangeofparameters;thesupportstresscoefficientapproachofT-N(09)isonlysuitableforelastic-perfectlyplasticrock,whichleadstoasmallersupportpressureandalargerstabledeformationofrockmass,andthustherelatedmaterialmodelsandparameterrangesshouldbeproperlyimproved.ThedisplacementreleasecoefficientapproachofV-D(09)canbeappliedtovariouselastoplasticrocks,directlyreflectingthechangesandinfluencerangesofspatialeffectofexcavationface,andthusithasawiderangeofengineeringapplications.Keywords:spatialeffectofexcavationface;supportstresscoefficient;displacementreleasecoefficient;supportpressure;stabledeformationofrockmass1214182016Gesta[1][2][3][4]Thomas[5]FLAC3DTN(09)Panet[6]1995[7][8]Unlu[9]Basarir[10]RMR[11]Hoek-BrownVlachopoulos[12]maxRVD(09)2TN(09)VD(09)21irRipop1Fig.1Atunnelingmechanicalmodel[13−14]1[15]R0u01yrroiiyirricot2,cot1CpcpYRrppcϕϕα+−==++1()()()()()001ioyr0iir11111i2i111CCppRurEECrRCrRββββββνν++++++++−+=+−+−⋅2()()()()()()()()iiirrr223sin21sin223sin21sinbbbbbbϕαϕϕαϕ+++=+−+++=+−3()()()()()()iiiirrrr41cos21sin41cos21sinbcYbbcYbϕϕϕϕ+=+−+=+−4()()()()()()()()()0r0rrrrrrrirr10i2rorr41sin21sin11cot112cotCbCbpcCCrCpcϕϕανβανανϕβνϕ+=+−−++−−+=++=−−+50C2CiαrαiYrYypβb01biciϕ51419rcrϕiEiνrErν3TN(09)3.10ipopi(1p=−)×oppi0i()px∗i()pxopiio()()/pxpxp∗=x0x=0x0x1Thomas[5]Mohr-CoulombFLAC3DipηϕTN(09)i()px∗()()1.2i1.2inflii0oinfl1/,0/pxxLpxpxpxLξξ∗∗−==+6i0p∗0x=inflLξ3ηϕmaximaxii/1RrRrrη−==−7infli(2.076.40)Lrη=+8()i011111cospabcdeηη∗=+++9()22222cosabcdeξηηη=−+++10111110.1314tan0.01290.0259tan2.62270.011tan0.64390.1854tan0.15930.1396tan0.8092abcdeϕϕϕϕϕ=+=−+=−=−−=−+11222222220.0236250.4604tan0.3749tan5.52760.0397tan0.015tan1.03270.0473950.0247tan0.006tan0.0039abcdeϕϕϕϕϕϕ==++=−+−==−−+12maxRpi=01a1e2a2eTN(09)i()px∗0xϕ2040η02.50η=maxiRr=η=2.5maxi3.5Rr=maxR3.5ir3.2TN(09)i()px∗maxRϕTN(09)11i0p=maxR27ηϕ810inflLi0p∗ξ6i()px∗3xi()px∗i()px0au3.360x0xϕ2040maxi3.5Rr26maxi/RrϕTN(09)i()px∗2maxRi()px∗ϕmaxi/Rrϕ120x=maxi/Rr=3.5i0p∗maxi/Rr=118.1%ϕ=40i0p∗ϕ=2064.9%2maxi/Rrϕ14202016(a)(b)2Fig.2Parametricstudiesofsupportstresscoefficient4VD(09)4.10u0()ux0maxu()ux∗00max()()/uxuxu∗=Vlachopoulos[12]Hoek-Brown2FLAC3DmaxRVD(09)()ux∗()()()()()()()0000max000max1exp0.15,03exp(),011exp1.5/,0uRxuxuxuxxuuxuxuxRxu∗∗∗∗∗∗∗∗∗=−=====−−−13*maxi/RRr=*i/xxr=0u∗0x=Rodriguez-Dono[16−17]FLAC3D13maxR13134.2VD(09)()ux∗maxRmaxi/Rr=1max/Rir1VD(09)112i0p=maxR0maxu2*i/xxr=13u∗0maxu0()ux0au30au4.3VD(09)()ux∗maxRmaxi/Rr3VD(09)()ux∗maxi/Rr3Fig.3Parametricstudiesofdisplacementreleasecoefficient3maxi/Rrmaxi/Rrmaxi/Rr=1x0.00.20.40.60.81.00123456Rmax/ri=1.0Rmax/ri=2.0Rmax/ri=3.0pi(x)/pox/riϕ=3001234560.00.20.40.60.81.0Rmax/ri=2ϕ=20ϕ=30ϕ=40pi(x)/pox/ri5.02.50.02.55.07.510.012.515.00.00.20.40.60.81.0u0(x)/u0maxVD(09)13Rmax/ri=1Rmax/ri=2Rmax/ri=4Rmax/ri=6Rmax/ri=8Rmax/ri=10x/ri51421VD(09)0xmaxi/Rr0xmaxi/Rr1.055.12TN(09)VD(09)216op130maxuFLAC3DmaxRx0au26Mohr-Coulomb13Hoek-Brown61360x136ϕmaxRϕ13maxRmaxR1362TN(09)ϕmaxR6ϕTN(09)VD(09)5.2TN(09)VD(09)C(x)[1]()()()()()()()00000max0max00100010uxuxuxuxCxuuuxux−−====−=−=14()00ux=C(x)4Thomas[5]TN(09)C(x)VD(09)4TN(09)VD(09)C(x)TN(09)max/Rir=2VD(09)TN(09)maxRTN(09)VD(09)maxR42Fig.4Spatialeffectcomparisonsbetweentwoapproaches6[18]opcσ420246810120.40.20.00.20.40.60.81.0TN(09)6,ϕ=30Rmax/ri=1VD(09)13C(x)x/riRmax/ri=2Rmax/ri=3Rmax/ri=1Rmax/ri=2Rmax/ri=3142220161bmsaHoek-BrownbrmrsraTN(09)Mohr-Coulombricc=riϕϕ=Hoek-Brownbrbmm=rss=raa=12Mohr-CoulombHoek-Brown12b=021