自然崩落法全英文六壹

CavingSubsidenceContentsCavingtheorySubsidenceprocessSubsidencezonesSubsidencepredictionDamagecriterionProcess3partcavingprocessDevelopareabigenoughtocaveCaveinitiationCavepropagationInitiationPropagationPropagationRemovalofsupportforthecavingblockMassmobilizationoforecolumnShearingofmajorstructuresin/aroundorecolumnFallsofgroundaroundcavefootprintChimneycavingonweakzonesandstructuresSurfacecrackingSubsidenceasdrawingcommencesPerimeterde-stressingExcavationcollapseduetolossofconfinementPropagationconditions&rates10%oforecolumnmustberemoved8-12%rangefortheabove.25%maximum(Hendersonmine)Majorstructurespresent8-9%Veryfast/notcontrolbydrawafter10%Majorstructures90minweek1m/day(Bartlett1997?)VoiddiffusionnotswellSubsidenceprocess1.Propagatethecavetosurface2.Centresubsidence3.breakbackStage1(PHOTOSCOURTSEYNEWCREST)Stage2Stage3progressionSubsidencezonesMarcodeformations(subsidence&cracking)Microdeformations(Groundtilts&strains)SubsidencezonesMACROMICROGloryholeMacroSubsidencedefinition(kazulavic1999)ImportantdefinitionsAlpha=angleofbreaktosurfacefracturezoneBeta=angleofcavetotheedgeofgloryholeTc=FracturezonearoundthegloryholeTi=undergroundfracturezoneH=muckpileheightAs=finalwidthofgloryholeRulesofsubsidenceWhat'sabovethefootprintisdestroyedWhatinthecrackedareaisdestroyed(angleofbreakzone)Groundtiltsandstrainwilldestroystructuresbeforemacrogroundmovements.Whatneedstobeknownis: -largestfootprintoutlineprojecttosurface

-Angleofbreak -Microdeformationalzone -criticaltilts&strainsofstructures/excavationsMacro/angleofbreak/cavedefinition

AngleofcaveisaFunctionof -Rockmassstrength -Muckpilesupport(H) -Depthofore\body -Majorstructures -Rockmass\shearstrength -HoopstressesAngleofbreak=angleofcave+perimeterfracturezone(Tc)AngleofcaveHastheirbeenanopencutOpencutassumeAngleofbreakNoopencutCavebelowopencutSlopedesign=c=0CavebreakangleCavebreakanglemethodsonlyAngleofbreakopencutHainesandTerbruuge1991slopeangledesign

RockmassstrengthadjustedforcohesionlossduetocavingAng善le糕of机bre汇ak/滩ca疤vin案gExp调eri射ent企ial物(Sco滨pe)-45积deg蚀ree劲so醉r7刻0d住egr等ees正an巡寿gle宿of泥br寇eakEmp单iri挎cal挤(De案fi堡ne)-L爷aub全sch拉er狡19接90,旁19谢97-K宪avu羊lar鸽vic壁19当99Str遣uct狭ura会l(ad嫌ju宵st宋me涨nt)-mod鞠ifi栗es最glo糕ry棕hol须e-云Enl玩arg皱es销glo欠ry郊hol庸es-顾S吹tr末uc愁tu晒ra绳l忍su文rv地ey-株De军te义rm民in寒is许ti准c麻an妖al肾ys昆is恒(借St责ac键ey勤&伶S娘wa棵rt黎2惰00够1)Lau栋bsc堂her富(e塘mpi段ric防al-壳199竭3)ConditionDepth(m)AdjustedMRMR9070503010Nolateralrestraint10080706050405007060504030Lateralrestraintfromcavedmaterial10090807060505008070605040La版ub稳sc辣he岗r猪(e祥mp简ir偶ic敏al蕉-蒙19接97棉)Ka得vu描la天rv波ic阻-挥19盏97Str懂uct丸ura给la歌dju区stm略ent旧(S匆tac硬ey废&S塌war瘦t2阅001诊)MI明CR寇O/戏Nu好me尾ri行ca败lMA宇P3卖D,嗓F困LA骑C筝2我&许3D种,阀UD狮EC己,拿3D洋ECCon击fir座mg悲lor煎yh盟ole抽po议sit钳ionMod袜el寄str贸ess刷ef蚁fec良tsFr沈ac贞tu版re坏z匠on旬eGr祖ou译nd销t亭il耕ts淡&黄s促tr跨ai或ns蜻a卧ro铲un扣d柄ho眼leIn黎fl歉ue麻nc表e拦of抄s帅tr随uc萍tu里re陕s-嚼F昆LA期CSt炉ru龙ct康ur拦es述r腰ed择uc尘e凡gr妈ou育nd罗s积tr症ai旦nsExc惭ava点tio攻ns漫tre成ss杠cha急nge酸(1犬0Mp益a?互???颗?)De代fo弄rm僚at响io折ns妄(扎St牙ac地ey锡&开S贵wa厨rt弹2俘00术0)Num哥eri付cal转(K氏ay南et企al墓199样1)Mic劝ro顿zon窗ed文ama派ge轰cri啦ter谦ionSh早af繁ts肉-原So坛ut晓h珍Af栏ri先ca丽n支c率ri窑te阻ri寒onBui霜ldi卡ngs王-U杰KS丝式ubs洽ide示nce屯en冻gin粉eer出sh茎and签bo乓ok父197剩5Me竟ch花an同ic秆s义an旁d苦co吩nc涝re略te弓w笼or蹄k顾fa隐il魄f涝ir势stFa嗽n耗fo傍un攻da添ti石on室sRe效in垦fo忠rc弄ed鄙c涛ol白la纯rs蛙c育an既s含us变ta酒in絮m逮aj醉or缺d淹am拍ag沾eFo械un姨da优ti惹on弯s添st候ro岭ng晋t兼o湾wi精th缺st眯an颤d司ti笔lt成s穴&达st辱ra历in匆sFou陶nda补tio啄ns状fle脂xib拢le借to疲wit赞hst东and雁gr叨oun苏dm屯ove袭men单ts.Sha疾ft殿dam俗age假cr茅ite桌rio主nTa搂bl苗e寒22看D皂am塞ag宜e夜cr昨it埋er许ia乘f货or困s凯ha穿ft谅s畅(m川od敢if袋ie弟d乒fr镜om预M蕉cK轻in允no绪n,晌1村98虑9)TypeofdamageCriterionReferenceUnspecifieddamagezi<17MPaWilson(1971)Unspecifieddamage,criterionnotbasedonbackanalysiszi<1x10-3Salamon(1974)zi<1x10-3Wagner(1985)zi<1x10-3Daemen(1972)ti<1x10-3Wagner(1985)Steelworkdamageandincreasedshaftmaintenancezi<0,2x10-3Wilson(1971)zi<-0,4x10-3VanEmmenisandMoreO’Ferrall(1971)zi<0,4x10-3Esterhuizen(1980)Tensilefractureofconcreteliningzi<-0,51x10-3to-0,3x10-3Kratzsch(1983)zi<-0,2x10-3Budavari(1986)Compressivefractureofconcreteliningzi<0,7x10-3JagerandRyder(1999)ST掀AN颈D-缝OF颗F烛RU快LE舟SSha芝fts成>袍200廊mf竟rom局ho怀leVe蛾nt唯p隙as劳se丽s循>7遥0m吓f沈ro烛m妥gl倾or酷y喜ho恭leSur忠fac车eb蜻uil恳din俊gs纤>10炕0m抢