自然崩落法全英文一二壹

(FREE-CAVING)-BLOCKCAVINGGeotechnicalContentsTypesofcavesUndercutdesignExtractionleveldesignBCgeotechissues2CAVETYPESHARDCAVES(MRMR>45,1000mdepthKratio1-2)CavestallFragmentationRock/strainburstingSOFTCAVES(MRMR<45,1000mdepth,Kratio1-2)Excavationlevel&UCstressinduceddamageUndercutcrushingStrain/rockburstingwhenMRMR>35RULESStrategicdesignControlgeotechnicalriskswithUCSupportistacticalissueMainissues -undercutdesign -extractionleveldesign -drawcontrolUndercuttingStressandburstprotectionmethodDowehaveafragmentationproblem?Dowehaveastressproblem?Weneedtoknow:StartpositionUndercutretreatdirectionCriticalHRStrategyGeometry“undercuttingisprobablyoneofthemostimportantofalltheactivitiesinvolved.Therefore,thecorrectdesignandmanagementoftheundercutiscriticaltothesuccessoftheblockcave.”BlockcaveundercuttingUndercuttingAimsUndercutStrategiesManagementConfigurationControlDrawControlPrePostAdvancedExtractionmethodFanFlatInclinedLags/LeadsBlastDrawAIM1-Extractavoidtoallowcavingto occurTheundercutsizetoinitiatecavingisrelatedtotherockmassqualityandhydraulicradiusAweakerorebodyrequiresasmallerhydraulicradiusHydraulicradiusofbetween8mand35mnormallyrequiredUndercuttingaimsAIM2-Initiatecavingwithminimum damagetorockmassAimrelatestostresscontrolStressmagnitudesincreaseasundercutsizeincreasesStresscontrolrelatestothepercentageofcavinghydraulicradiusextractedUndercuttingaimsAIM3-AdvanceHRtoreducestressesRequiresundercuttoadvancefromweakertostrongergroundPropagationofcaverequires8-12%drawofblockreserveFulldestressingnormally25-30%ofblocktonnageisdrawnTunnelsmaybesubjectedtoundercutabutmentstresseslongerUndercuttingaimsUndercutextentStressconditionRemarks25%ofHRLowLimiteddamage50%ofHRBecomingaconcernOnsetofcriticaldamage75-110%ofHRMaximumSeveredamageSupercaves(MRMR>45):Stresslevelbecomesaconcernforextraction>75%ofHRUndercuttingAimsUndercutStrategiesManagementConfigurationControlDrawControlPrePostAdvancedExtractionmethodFanFlatInclinedLags/LeadsBlastDrawUndercuttingstrategiesPreundercuttingReducedstresses,productiondelays,compactionremnantsPostundercuttingFasterproduction,stressinduceddamage>60%extractionratio-severedrawhorizondamage,500moperationlimitAdvancedundercuttingLimiteddrawhorizondamage<60%criticaldrawhorizonextractionlimitStrategiesUndercutdevelopedbeforedrawhorizonAdvantageReducedstressdamagePREUNDERCUTTINGStrategiesDrawhorizonfulldevelopedthenundercutAdvantageBlockbroughtintoproductionquickerDisadvantagesDrawhorizonstressinduceddamages,driftrepair,productiondelaysPOSTUNDERCUTTING(conventional)StrategiesDrawhorizondamagerelatestostressmagnitudeanddrawhorizonextractionStressmagnitude2-3timeshigherthanthepre-undercutlevelsSeveredamageoccursat60%drawhorizonextractionCollapseoccursat80%drawhorizonextractionLimitingoperationaldepth±500mPOSTUNDERCUTTING(conventional)StrategiesLimitedamountofdevelopmentondrawhorizonbeforeundercuttingDriftsbeforeundercut,crosscutsanddrawbellsafterundercutKeepdrawhorizonextraction<60%(Butcher1999)ADVANCEUNDERCUTTINGStrategiesAdvantagesdrawhorizondamageisreducedthecaveisbroughtintoproductionquickerthanwithapre-undercuttingstrategyaseparatelevelisstillrequiredforundercuttingthisstrategyisslowerthanpostundercuttingDisadvantagesSomedrawhorizonSlowerthanpostundercuttingADVANCEUNDERCUTTINGUn防de留rc注ut佩ti菊ng皮a麥im兼sAI覺MS辰–棚W喊ha譜t沉ar針e瓦we冷t幫ry學(xué)in捉g器to老d萄o?Ext怎rac箱ta鳥vo堪id押to才all托ow番cav請ing雁to槳oc收curIn訪it竊ia待te榴c廈av套in燙g夠wi鏡th減m籍in嗚im銅um路s請tr富es懶s會da眉ma補gePro喪pag拆ate喘th近ec習(xí)ave靈to竹re熊duc口eu摩nde飾rcu勤ta掛but廚men柏ts升tre扎sse僚sUnd暖erc屯utt細(xì)ingAi笑msUn青de般rc子ut盼S彈tr寄at注eg向ie翠sMan躲age先men斤tCon侵fig廢ura敗tio老nCon朝tro基lDra外wCon即tro脂lPr涌ePo蓄stAd角va差nc躲edEx羅tr稀ac震ti添on潛m拔et段ho綁dFa衣nFla岡tInc立lin合edLa貢gs逢/L初ea驕dsBla化stDr著awEx烏tr蠅ac旱ti負(fù)on優(yōu)m央et低ho兵dsCON悼SID幕ERA商TIO總NSDe寨pt子h/粱st廉re殘ss蹈r緩eg違im熟ena持rr脹ow鄭u流nd格er干cu閃ts尚–于h舊ig弟h睡s舅tr拖es炊se觀sSk買il槍l掃le掃ve齒l席of泳c殃re誰ws噴mo陸st蒼c屋ri艇ti府ca拍l只as悅pe貞ctTec掌hno弟log跪y爆3rdwor居ld猜cou腫ntr繪iesReq覽uir乓eb硬loc焰k僵pr盯od葉uc柄ti希on傳m甲et偏ho凳dton斑nag版eUnd倉erc社ut鋤hei刃g(shù)ht掀s森st赤re爭ss是d遍am趴ag晚e嚼–斷l(xiāng)虛ow肆t怕on程s服–撿hi遠(yuǎn)ghEx速tr毯ac狀ti澡on膀m枝et閘ho希dsBlockcavefanundercutwithoutseparatelevelEx悟tr償ac排ti不on上m撐et梅ho熟dsConceptualPlanofflatundercutshowingpossibleproblemareasEx兆tr械ac雪ti包on進m葵et蕉ho役dsInclinedundercutpotentialproblemareasUnd姿erc喝utt滑ingAi放msUn規(guī)de袖rc裂ut掀S桌tr鏈at壤eg聚ie接sMa啊na煮ge蔽me據(jù)ntCon灶fig都ura伸tio依nCo飾nt劣ro插lDr滋awCon頓tro蛙lPrePo葉stAd議va脂nc拉edExt植rac焰tio旋nm尾eth鬧odFanFl坑atIn燦cl絨in瘦edLa講gs融/L弦ea寧dsBla汗stDra雀wUn醬de任rc嗎ut歪m唐an協(xié)ag旨em橡en謊t“Man求age剪men芽ti強sp英rob拉abl頑yo遇ne嫌of墓the聚mo待st裂neg嚇lec籍ted曠as論pec型ts嘆of糕blo耍ck茶cav洲ei唱mpl筆eme城nta策tio砍n;塘wit余hu銜nde芒rcu劫tti非ng帶pro今ble鈴ms型bei集ng電due如to桶po臺or倉man岔age仆men榴tr追ath次er友tha移nd悲esi客gn”Und階erc堡ut奴man仔age弄men麥tLag很co孔ntr玻olUndercutfrontlagdistance(caveline)UndercutfrontstressconditionDamage<5mIdealMinimum8mModerateModerate10-12mHighSevere>12mVeryhighUndercutfrontcrushingSu閱pe采r眼ca島ve憤s沙–辜12邊-1登8m性l哪ag穴s炕to拍le桃ra此te皮d裙to抵7菊5%婚H通R<12堵ml跡ags潛fr罪om私75%出HRUnd額erc篩ut代man攔age沖men把tLag深co艇ntr位olUndercutstage

(%ofrequiredHR)TolerablefacelagdistanceConfigurationreviewperiod0-25%5-8m7-14days25-50%5-8m7-14days50-75%5m7days75-100%2-5mDailyUnd嗓erc架ut叮man簡age念men碼tRa饞te給o我f茂ad僚va太nc癥esAdv牽anc勞ea繩sr失api廳dly予as胳po彈ssi蓬ble卸to患HR六wi蹲tho猴ut勇inc枯urr規(guī)ing企pr箏obl耗emsRed瞞uce丘ra煮te腿of警adv糟anc蘆ef村rom謠HRCa跪ve傲t赴on換s怕>注un廳de崖rc拘ut脈t狐on凍s鍬-給pr霧ev者en腿t月ar良ch仁i敵nd靜uc融ed風(fēng)a掩bu潮tm展en絹t扇cr嶄us赤hi驢ngRa隆te顧o材f植ad飲va亡nc色e±23將00法m2/m振on往thUn辭de粱rc謝ut講d稿ra倆w韻co妥nt零ro憶lTo足pr帆ev扮en屆t盞th蠟e抄ov蔑er爽o垃r移un目de秤r評dr晨aw搶o選f壘bl濱as錢te愛dgro頃undin朝cr煩ea名se啞d哨st執(zhí)re恥ss運es鄰d堡ue脂t拍o豆re歐mn獲an踩t謝pi奶ll幻玉ar讓s頌ca坊us得ed幅b乳y及ch繡ok尚e筆bl悠as帖t去co環(huán)nd去it鬼io海nscru拒shi鹽ng菊of林tun仿nel岔si則nt狗he漏cou脖ntr越y(tǒng)r蓮ock鏈du歸et漸oh雖igh犯dr火aw傳rat濁es末fro射mdr北aw虹po任in膊tssl枝ow蹲r屬at白es恭o罪f隱ad禁va通nc溝e,ca盆ve增d州gr振ou住ndflo攻odi矩ng把und墊erc厘ut西lev卷eldr既aw截po朱in沙tmo間ut須hsmu燒ck主pi唇lesta謠cki寫ng李due細(xì)to凍un皇der紀(jì)dr徒awUn泛de晚rc姐ut叼d巨r(nóng)a另w鐵co融nt怖ro顧lUn定de公rc俊ut攻d隨ra糟wTry伯to釋dr秩aw賴swe滋ll指onl控yDo供n位ot穿d食ra捐w鍬mo摔re牲t浮ha隨n舞10乒0%把o傻f肯ri磁ng襖t讓on尸na連geDr阻aw槍a饞cr剩os擺s替th碰e愛un最de殺rc陵ut項s敵ho膏ul護d冊be崗4燥0-腥70粉%淘ri般ng鉗t蹦on亦na攝geEx魯tr看ac課ti調(diào)on冊l青ev姜el描d耳es伴ig服nDr克aw紗i作s既ki鈔ngInt觸era悶cti攜ve蠟lay闖out夫sSt痕re遠(yuǎn)ss菠/就fr哄ag勒me晃nt落at蝦io長n僵cu榜t-無of冒f籠fo側(cè)r膚us帥eSof糠tc兄ave弟sh誘eav棍ys瞧upp辮ortHar責(zé)dc資ave找sl憂imi物ted陣su株ppo噴rtExt植rac躁tio孤nl兆ayo槐utsEx療pe而ri耐en身ti刻alNo娛rt班h洋Am概er當(dāng)ic閃aSo躁ut顏h瞧Af騙ri赴ca份/美Zi乞mb飛ab午weCh纖il返eMRM犯RBin倉sf植or曠int繭era蛛cti圣onExt叮rac口tio潤nl圾eve相l(xiāng)l剖ayo婦utTyp閑esDe顏si欺gn栗a抬sp奮ec顯tsDra聽wbe幟ll/此po仇in愈t竊sp動ac腔in謝g-MR蠢MR-貌I競CS穴M壯RM蝴R靜pr舍og永ra朋m-盆P訂FC-挪S各an賴d廊bi惡ns予/翠ph析ys雞ic堵al甘t銜es擺ts-播ex紗pe存ri畫en獲ceDR漠IV覺ES項/獵CA絡(luò)MM翠EL堆B壞AC越KS澆/談BR嘴EA揮KA涼WA裙YS-糟sp感an分s-津pi輔ll婆ar得s-槳ex艦pe灑ri投en因ce-勝Nu糊me鴿ri鉆ca雪l舟mo滔de咬li絲式ngSu密pp旁or蘆t-MRM樣R-Ex躲pe鑼ri抖en忘ce-Mod餐eli乖ng-族De其te狠rm噴in之is怨ti刪cDra視wl溪ayo仔uts錄1.猴5I屯FAI努MDr闊aw畏be令llin允te什ra叼ct掙io敞nEx活pe棄ri層en秩ce5r呆ece雜nt樸cav掀esDr蝦if杜ts績4限.2坦m蘇X護4.精2mDri律ft跑spa辱cin篩g2爽8-扯34m滋(3脂0m)Dra紹wp因oin階ts搶pac久ing餅14捷-1踩8m逼(16策m)Off出set釋-he家rri鍛ngb應(yīng)one希-r正edu離ced澤sp高ansDi塵st姓an搜ce介t異o難UC臂1提5mMA臥SS鄭MI葉N秋20衛(wèi)00Sup污por敢tMR眠MR啦m攜ap凍pi撇ng凍&基d御om探ai盛nsMRM袍Rt珍abl木es貌to族sco誕pe再sup萬por例tUs芝e黎di衣ff狀er趁en啦t滑ad開ju役st性me弄nt具s混,疊K明is疫n鈔ot依1199籍4B北olt失se坦qua倘tio芬ns詞sus逮pec號tEx桑pe次ri仗en亡ce毫:-1m避p員at派te挨rn禾o成f閉2.上4m災(zāi)b展