极软厚煤层大采高台阶式综采端面煤岩稳定性控制研究

376Vol.37No.6200811JournalofChinaUniversityofMining&TechnologyNov.2008:20080316:(2007CB209400);(50774079);(20050290503):(1965),,,,,,.Email:[e-mail]:051683883447刘长友1,黄炳香1,常兴民2,王君1,魏民涛2(1.,221008;2.,461670):基于对极软突出厚煤层大采高综采工作面端面煤岩稳定性的有效控制,提出了台阶式采煤工艺,采用台阶式割煤方式;用数值模拟分析了台阶式割煤的防片帮机理.现场实测分析了大采高开采工作面在采用台阶式回采工艺条件下端面煤岩的失稳特征.研究表明:台阶式割煤工艺改善了煤壁区域的应力状态,减少了工作面煤壁片帮和端面冒顶的发生不同台阶高度比割煤所引起的围岩破坏程度不同,上下台阶高度比为12时煤壁塑性破坏区最小;极软厚煤层大采高开采煤壁片帮主要以剪切滑移引起的三角斜面片帮为主,超高开采是端面顶板冒落的主因.:极软厚煤层;大采高;台阶式割煤工艺;煤壁片帮:TD32:A:10001964(2008)06073406StudyonTiptoFaceCoalandRockStabilityControlofFullyMechanizedSteppedLargeCuttingHeightMininginExtremelySoftThickSeamLIUChangyou1,HUANGBingxiang1,CHANGXingmin2,WANGJun1,WEIMintao2(1.StateKeyLaboratoryofCoalResourcesandMineSafety,SchoolofMines,ChinaUniversityofMining&Technology,Xuzhou,Jiangsu221008,China;2.GroupofHenanShenhuocoalelectricity,Yongcheng,Henan461670,China)Abstract:Inordertocontrolthesurroundingrockmassstabilityoffullymechanizedlargecuttingheightfaceinextremelysoftcoalgasburstthickseameffectively,steppedminingtechnologywaspresented.Preventionribspallingmechanicsofsteppedcuttingtechnologywasanalyzedbynumericalsimulation.Theinstabilitycharacterofcoalorrockintiptofaceareawasanalyzedbyfieldobserving.Theresultsshowthatthesteppedcuttingtechnologyimprovesthestressstateincoalsidezone,andreducestheoccurrenceofsloughingandtiptofacearearoofcaving.Surroundingrockmassdestroydegreeinducedbydifferentsteppedheightratioisdifferent.Coalsideplasticzoneofupanddownsteppedheightratio12isleast.Mostribspallingistriangularslopsloughingcausedbyshearslippinginhighseamminingwithextremelysoftthickseam.Ultrahighminingisthemajorreasontopfaceareaforrooffall.Keywords:extremelysoftthickcoalseam;largecuttingheight;steppedminingtechnology;ribspalling6:,,.50m,,,,,,.,,.1,,,,0~1079m,418m,3~6m,22~87m,46m.f=015~025,018.,,,,,;,,.,.111041,563m,166m,1.37~57m,46m,8~15,12,425491~461084m.11041,.ZY6000/25/50(1)MGTY300/73011DSGZ764/2!315(630).5m,37~48m,46m;,,()800mm.∀#,35~42m.(1).,,.:,22~25m,,5m2~3m,,.,().1ZYG6000/25/50Table1MajortechnologyparametersofZYG6000/25/50twolegshieldsupports/m25~50/m143~16/m15/MN5067(P=315MPa)/MN6000(P=373MPa)()/MPa129~326/MPa085~0901Fig.1Schematicplanofsteppedcuttingtechnology2211),128m!72m.,x,y;X,Y,,78MPa.48m,56m,32m.,30m,(2).2Fig.2Numericalmodelalongminingdirection2),,,73537,(HoekBrown)[1]1s=3+(mc3+s2c)1/2,:1s;3;ms,;c.,,.2.3).,,2,.,,E,[2]=1600+800(1-e-125t),(1)E=15+175(1-e-125t),(2)v=005+02(1-e-125t).(3)2Table2Physicalandmechanicalparametersofrocksandcoal/(kg∃m-3)/MPa/MPa/MPa/MPamsms2590100060058725850189058500192650190160110857001000070000902570190157075685620172056200171130008504001021000003010000032650100078098595520143055200142740190152065705690181056900184)30m().,4:,,08m;,11,08m,;,12,08m,;,21,08m,.3Fig.3Propulsivemannerofeachminingtechnics22,02m,.1),:(4),,1MPa,,(1:2)38MPa;(5):,,02MPa,08m07m0~03MPa.2),015MPa,02m,4,,.,54.7366:4Fig.4Shearingstresseshorizontalstressesandadvancesupportingstressesofeachprogrammeafterminingtheupperstep5Fig.5Shearingstresses,horizontalstressesandadvancesupportingstressesofeachprogrammeafterminingthelowerstep:,,.,,;,,,.23,6.,,1~3cm.,.,12(),.6Fig.6Differenceofleveldisplacementabouteachprogramme247.7Fig.7Plasticareadistributioninsurroundingrockoftheworkface,(11)669m(12)659m(2:1)666m,682m.,,,73737.,12,,.331,,,70%.,03~08m.,15m,,.,,,.,,.05~15m.,.32,,.,,,.,.1).,135m,,2.531MN,50%.,,,,60%.,.2).,,,,,.3).,,,.33,,,,,,,,.8~10t/,364~455t/,.41),,,,,.2),,,.,.3).12,1121,1:2(16m,32m),;11(24m).2000mm,11(24m).4),.,,.:[1].[J].,2006,34(1):47.WANGJinhua.PresentstatusanddevelopmenttendencyoffullymechanizedcoalminingtechnologyandequipmentwithhighcuttingheightinChina[J].JournalofChinaCoalScienceandTechnology,2006,7386:34(1):47.[2].[M].:,2001.[3].[J].,2007,32(8):785788.WANGJiachen.Mechanismoftheribspallingandthecontrollingintheverysoftcoalseam[J].JournalofChinaCoalSociety,2007,32(8):785788.[4],,,.[J].,2002,31(1):6974.FANGXinqiu,QIANMinggao,CAOShenggen,etal.ResearchonTiptofaceroofstabilityanditscontrolfordifferenthardnesscoalsinfullymechanizedtopcoalcavingmining[J].JournalofChinaUniversityofMining&Technology,2002,31(1):6974.[5],.[J].,1998,8(5):2831.XUJinhai,ZHANGDingli.Preventionandcontrolofendfacefallinfullymechanizedsublevelcavingminingface[J].ChinaSafetyScienceJournal,1998,8(5):2831.[6],.[J].,2004,14(6):109112.CAIChenggong,WANGYouan.Qualitativeandquantitativeanalysisofgeneralregularityofcoalandgasoutburst[J].ChinaSafetyScienceJournal,2004,14(6):109112.[7]LIWenping,LIXiaoqin,SUNRuhua.AnestimationmethodofstressinsoftrockbasedoninsitumeasuredstressinhardRock[J].JournalofChinaUniversityofMining&Technology,2007,17(3):310315.[8],,.[J].,2007,36(1):1722.LIUGang,ZHAOJian,SONGHongwei.Numericalsimulationoninfluenceofjointdistributionsonfailuresofrockmass[J].JournalofChinaUniversityofMining&Technology,2007,36(1):1722.[9],,.[J].,2003,20(3):2127.HAOHaijing,ZHANGYong,YUANZongben.Integralmechanicsmodeloflargecuttingheightminingfaceandtheeffectofstratabehavior[J].GroundPressureandStrataControl,2003,20(Supp3):2127.[10],.[J].