外文翻譯--關(guān)于傾角煤層挖掘巷道的錨桿支護(hù)的研究.doc

中國(guó)礦業(yè)大學(xué)2007屆本科生畢業(yè)設(shè)計(jì)第66頁Where,1listhelengthofboltedend；2listhelengthofouterpart.Boltspacingacanbederivedbythecriteriathatnoslipoccursalongbeddingplanes.Besidestheabove-mentionedconditions,thesafetyofthecombinedbeammustbecheckedtopreventitfromlongitudinalinstability.Whenalltheconditionsaresatisfied,roofboltparameterscanreadybedetermined.Asforsidewallbolts,theirlengthandspacingcanbederivedbysoilbracingtheoryinsoilmechanics.Itshouldbenoticedwhenroofiscomposedofweakandloosestrata,somebracingmeasuresmustbetakentoprotecttheintegrityofthefragileroof.1.Boltingofthegatewayanditsassessment1.1SupportassessmentbydiscreteelementmethodWeconsidertwocaseinordertocompare,firstcase:onlytheroofisbolted；secondcase:bothroofandsidewallarebolted.Havingbeenboltedinthefirstcase,theroofhasaobvioushigherstiffnessandstrength,intheinitialstage,onlyslightdeflectionoccurs.However,withthesidewallcoalfailingandcaving,thefreespanoftheroofincreases,theroofgraduallyentersunstablestage,subsidingandbeddingseparatingasshowninFig.5.Comparedwiththeunsupportedgateway,thegatewaywithroofboltedcankeepstabilityformuchlongertimeevenitdestabilizesfinally.Inthesecondcase,thesidewallcoaldeformationandfailurearestrictlycontrolledbythesidewallbolts,thesidewallsarestable.Roofdeflectsonlyasmallamount.Displacementcanbehardlyseenintheblockdiagram(Fig.6).中國(guó)礦業(yè)大學(xué)2007屆本科生畢業(yè)設(shè)計(jì)第67頁Theoverallsurroundingstrataareinstableconditions.Eveninfluencedbyminingactivitythegatewayonlyfailslocally,theroofis,howeverratherstable.Itis,thusimportanttoadoptacomprehensiveboltsupportpatternincludingthesidewalls.1.2BoltingschemeanditsimplementationBasedontheinclinedcombinedbeamtheory,gatewayloosedzonemeasurementanddiscreteelementanalysis,fourbolts1.6mlongareinstalledintheroof.Attheouterendofeachbolt,atestingdeviceisinstalled(5patentofNationalBureauofChina)toensurethatatleast20kNpretensionisexerted.Boltspacingis0.75m,arraypitchis1.0m.Duetoratherdevelopedjoints,steelbendsareusedtogetherwithroofbolttoensuresupporteffectivenessandpreventlocalroofcaving.Thesteelplateis0.01mthick,0.89mlongand0.1mwide.Thecoalsidewallisreinforcedbytimberboltwithspacing1.0m,timerboltforuppersidewallis2.0mlongand1.0mforthelowersidewall.Thetimberboltisinstalledwithnoless7.5kNpretension.Intheinfluencezoneoffrontabutmentpressure,strengthenedsupportsareadded.Metalfrictionalpropwithtimbercapissetastemporaryreinforcement.Thereinforcementdistanceis25maheadoftheworkingface.Thereinforcedpropsarearrangedinthecenterlineofthegateway.Moreattentionsshouldbepaidtogatewayexcavationprocedure.Theroofboltsshouldbeinstalledassoonaspossibleaftertheroofisexposed,thenthesidewallbolt.Themaximumdelayedtimeshouldbelessthan6hours,whichcanmaketheroofdeformexceedinglyandintegrityworsening.Aftereachconstructioncycle,theboltsnearthedrivingfaceshouldberefastenedtoassuretheiranchorageforce.1.3MeasurementofgatewayclosureInordertoassesstheeffectivenessofthesupportscheme,thegatewayclosureismonitoredduringitsdrivingandworkingfaceretreating.Theclosureofroofvsfloor,sidewallsandroofsubsidingvelocityareshowninFig.7.中國(guó)礦業(yè)大學(xué)2007屆本科生畢業(yè)設(shè)計(jì)第68頁Itcanbeseenthatwhentheworkingfaceisfarawayfromthemonitoringarea,thedeformationofthesurroundingrocksisverysmall,indicatingthatthegatewayisnotinfluencedbyfacedynamicpressure,thesupportsystemcaneasilybearthestaticloadofgatewayitself.Withtheworkingfaceadvancing,thegatewaybegintosensethedynamicactionoftheworkingface.Whenthedistancebetweenthefaceandmonitoringareaisaround20meters,thedeformingvelocityofsurroundingisincreasingobviouslyandthestrataismovingremarkably,suchresponseofthegatewayisthedynamicactionoftheworkingface.Thetestingresultsshowthatthereinforceddistanceshouldbemorethan20meters.However,fromtheoverallstatusofthesurroundingrock,thegatewayisinstableconditionsandcansatisfythedemandofcoaltransportation,airintakeandotherengineeringfunction.Inspiteofthefactthatthereare23groupsofjointsdistinctivelyshowniftheroof,theroofis,howeverstableunderthecombinedactionofroofboltsandsteelbens.Theuppersidewallcoalfailsandfallsinsomeplaces,butthedepthislimitedwithin0.6m.Basedonthefactsinfield,inbrief,thesupportschemeisrationalandeffective.Goodeconomicandrechnicalbenefitwereobtained.2.ConclusionThefailurepatternofgatewayininclinedseamisremarkablyanisotropic.Thefailurezoneisnotonlyrelatedtothemechanicalpropertiesofstrata,butalsocloselytothestabilityofsidewallcoalbody.Thesidewallcoalfailurecausestheabutmentpointstotransferintodeepsolidcoal,increasethefreespanoftheroofandthereforeworsentheroofintegrity.Itis,thusakeytasktokeepthegatewaysidewallsoundingatewaymaintenance.Bygatewayloosedzonetesting,combinedwiththeinclinedcombinedbeammodel,boltparameterscanbereadilydetermined.Discreteelementmethodcanbeadoptedtoverifytherationalityandmakesomeamendment.Asfortheroofwithmultiplesoftandlooselayers,ensuringboltpretensionandinstallingroofboltsasearlyaspossiblearethekeystomaketheroofstable.Meanwhile,tokeeproofintegritywithsteelbends(sometimesmetalnetisneeded)isanotherimportantmeasure.Itisprovedthatboltingcanbeuseingatewaywithfragileandweakroofaslongasnecessarymeasuresaretaken,considerableeconomicbenefitcanbeobtained.中國(guó)礦業(yè)大學(xué)2007屆本科生畢業(yè)設(shè)計(jì)第69頁References1.陶連金.大傾角煤層開采礦山壓力顯現(xiàn)及其控制學(xué)位論文.沈陽：東北大學(xué).1996。70792.候朝烔.郭宏亮.我國(guó)煤巷錨桿動(dòng)手術(shù)的發(fā)展方向：煤炭學(xué)報(bào)，1996，21（2）：1131183.陳炎光主編.中國(guó)煤礦巷道圍巖控制.徐州：中國(guó)礦業(yè)大學(xué)出版社，1995（34）：67704.陶連金.寶山煤礦巷道圍巖松動(dòng)范圍測(cè)試.建井技術(shù),1993(34):67705.劉明遠(yuǎn)，陶連金，李芳成等.錨桿預(yù)緊力標(biāo)示圈.1993,國(guó)家專利號(hào)：93208997.6中文譯文關(guān)于傾角煤層挖掘巷道的錨桿支護(hù)的研究摘要一種典型的巷道是使用完全可變形的離散元素法。巷道周圍的斷裂區(qū)域是有規(guī)則的。在測(cè)量結(jié)果和理論分析的基礎(chǔ)上，一種全新的使用錨桿和鐵板的支護(hù)方案被提出。離散元素法被用于評(píng)估錨桿支護(hù)方案，并且取代了在現(xiàn)場(chǎng)上經(jīng)常采用的監(jiān)測(cè)手段。自從投入到實(shí)際應(yīng)用以來，這種方案被證實(shí)是成功的和正確的。對(duì)于理論分析和現(xiàn)場(chǎng)的監(jiān)測(cè)，一些在巷道螺栓連接的實(shí)踐中必須被注意的關(guān)鍵點(diǎn)最好還是總結(jié)一下。關(guān)鍵詞傾