资源描述：
《第六章 采煤工作面矿山压力基本概念》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、第六章采煤工作面矿山压力基本概念ThesixthchapteristhebasicconceptofcoalminingfacepressureSection1basicconceptofminepressureFirst,theconceptofminepressureMinepressureisduetoundergroundexcavationwork,whichdestroysthestressbalancestateofrockintherockmass,andstressesredistribution,The
2、forcethatexistsintherocksurroundingtheexcavationspaceandactingonthesupportiscalledtheminepressure.Two.Sourcesofminepressure1,selfstress2.Tectonicstress:3.Expansionstress:stresscausedbywaterexpansionandtemperaturechangeandgaspressure(1)selfstress-stresscausedbyover
3、lyingstrataweight;1,thegoldenNickhypothesis:Sigma1=gammaH,sigma2=sigma3=lambda1R=maxInstyle:Verticalstressesinaunitofsigma1--MPaThelateralstressesintheunitsofsigma2andsigma3--,MPaPoissonratioofunitrockstratum;Gamma-averageweightofoverlyingstrata,kN/m3;Thedepthofth
4、eH--unitfromtheground,MCoefficientoflateralpressureMax--maximumshearstress,kPaObviously,thegreaterthemuonvalue,thegreaterthelateralstressproducedbytheelementunderverticalstress.2,thehypothesisthatwiththeincreaseofthedepthofmining,orbecauseofrockandotherreasons,mak
5、ing"Mu=0.5",thatis:Sigma1=sigma2=sigma3=gammaHTheso-calledhydrostaticpressurestate,thatis,theverticalstressoftherockmassinthedeeppartoftherock,isproportionaltotheweightoftheoverlyingstrata,andthelateralstressisapproximatelyequaltotheverticalstress.(two)tectonicstr
6、ess-internalstressinducedbycrustalmovementinrockmass.Characteristics:1.Horizontalstressisthemainstructuralattraction,whilehorizontalstressmainlydependsoncompressivestress;2,inthetectonicstressfield,themagnitudeanddirectionoftheprincipalstressmayvarygreatly;thehori
7、zontalstressvalues(sigma2andsigma3)inthetwodirectionsareusuallynotequal;3,themeasurementshowsthatthehorizontalstressisgreaterthantheverticalstress,thatis,thehorizontalstressisgreaterthantheverticalstressSigmaHmax>Hmin,>V(4)tectonicstressiscommoninhardrockformation
8、s.Three,theminepressureappearsUndergroundpressure,themacroscopicphenomenaofsurroundingrockandsupportingmaterialshowssuchasmechanics,rockdeformation,dela
