版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請(qǐng)進(jìn)行舉報(bào)或認(rèn)領(lǐng)
文檔簡介
1、TunnelStabilityAnalysisofTunnelExcavationAspillwaytunnelfanembankmentdamistobeconstructedinapoqualitysstone.Theexcavateddiameterofthetunnelisabout13mthecoverovertheroofis8m.Thetunnelistohavea1.3mthickunreinfcedconcreteli
2、ningafterplacementofthisliftinga28tohighptionoftherockfilldamwillheovertheconstructedtunnel.Thequestionstobeaddressedare:(1)Whatsupptisrequiredindertoexcavatethetunnelsafelyundertheveryshallowcover(2)Istheproposedtophead
3、ingbenchexcavationsequenceusingdrillblastmethodsappropriatefthistunnel(3)Howwilltheconcreteliningrespondtotheloadingimposedbytheplacementof28mofrockfilloverthetunnelIndertoanswerthesequestionsaseriesoftwodimensionalfinit
4、eelementanalyseswerecarriedusingtheprogramPHASE`.Thefirstoftheseanalysesexaminedthestabilitysupptrequirementsfthetopheadingexcavation.Thefinalanalysisincludedtheentireexcavationsupptsequencetheplacementoftherockfillovert
5、hetunnel.Therockmassisapoqualitysstonethatbeingclosetosurfaceisheavilyjointed.ThemechanicalpropertiesassumedfthisrockmassareacohesivestrengthC=0.04Mpaafrictionangleof40amodulusofdefmationE=1334MPa.Noinsitustressmeasureme
6、ntsareavailablebutbecauseofthelocationofthetunnelinthevalleysideithasbeenassumedthatthehizontalstressnmaltothetunnelaxishasbeenreducedbystressrelief.Themodelisloadedbygravityaratioofhizontaltoverticalstress0.5isassumed.A
7、simplifiedversionofthemodelwasusedtoanalysethestabilitysupptrequirementsfthetopheading.Thismodeldidexcludetheconcreteliningthebenchexcavations.Thefirstmodelwasusedtoexaminetheconditionsfafullfaceexcavationofthetopheading
8、withoutanysuppt.Thisisalwaysausefulstartingpointinanytunnelsupptdesignstudysinceitgivesthedesigneraclearpictureofthemagnitudeoftheproblemsthathavetobedealtwith.embeddedintheshotcretewheregroundconditionswereparticularlyd
9、ifficult.Inthecaseofthetopheadinginsstoneunderconsiderationheretheshotcretesolutionwasrejectedbecauseinspiteofthefiniteelementanalysisthedesignersdidnothavesufficientconfidenceintheabilityoftheshotcretelayertosupptthelar
10、gespanofblockysstone.Inadditionthecontractonthisdamprojectdidnothaveagreatdealofexperienceinusingshotcreteintunnelsitwasunlikelythatthewkerswouldhavebeenpreparedtooperateunderacoverofshotcreteonly.Anotheralternativethati
11、scommonlyusedinexcavatingtunnelptalsistousesteelsetstostabilisetheinitialptionofthetunnelunderlowcover.Thissolutionwkswellinthecaseofsmalltunnelsbutinthiscasea13mspantunnelwouldrequireveryheavysets.Anadditionaldisadvanta
12、geinthiscaseisthattheinstallationofsetswouldpermittoomuchdefmationintherackmass.Thisisbecausethesteelsetsareapassivesupptsystemtheyonlycarryaloadwhentherockmasshasdefmedontothesets.Sincethistunnelisindefmationofadamexces
13、sivedefmationisclearlynotacceptablebecauseoftheadditionalleakagepathswhichwouldbecreatedthroughtherockmass.Thesolutionfinallyadoptedwas“browed“fromtheminingindustrywhereuntensionedfullygrouteddowelsarefrequentlyusedtopre
14、suppttherockmassaboveundergroundexcavations.Inthiscaseapattern3mx3mpatternof15mlong60toncapacitycableswereinstalledfromthegroundsurfacebefeexcavationofthetopheadingwascommenced.Whenthesecableswereexposedintheexcavationfa
15、ceplateswereattachedtheexcesscablelengthwascutoff.Inadditiona2mx2mpatternof6mlongmechanicallyanchedrockboltswereinstalledradiallyfromtheroofofthetopheading.TheresultsofananalysisofthissupptsystemareillustratedinFigure18.
16、3Figure18.4whichshowtheextentoftheyieldzonethedefmationsintherockmassabovethetopparingFigure18.1Figure18.3showsthattheextentoftheyieldzoneisonlyreducedbyasmallamountbytheenstallationofthesupptsystem.Thisisnotsurprisingsi
17、ncesomedefmationoftherockmassisrequiredindertomobilizethesupptingloadsintheuntensionedcables.Thisdefmationoccursasaresultoffailureoftherockmass.Figure18.4showsthatthedisplacementsintheroofofthetopheadinghavebeenreducedsu
18、bstantiallyasaresultoftheplacementofthesuppt.Howeverasmallproblemremainsthatistheexcessivedisplacementoftherockbetweentherockboltfaceplateswhicharespacedona2mx2mgrid.Unlessthisdisplacementiscontrolleditcanleadtoprogressi
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請(qǐng)下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請(qǐng)聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會(huì)有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 眾賞文庫僅提供信息存儲(chǔ)空間,僅對(duì)用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對(duì)用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對(duì)任何下載內(nèi)容負(fù)責(zé)。
- 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請(qǐng)與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對(duì)自己和他人造成任何形式的傷害或損失。
最新文檔
- 股利政策-畢業(yè)論文外文文獻(xiàn)翻譯
- 化學(xué)專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯
- 庭院設(shè)計(jì)-畢業(yè)論文外文文獻(xiàn)翻譯
- 管理專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯
- 化學(xué)專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯
- 畢業(yè)論文文獻(xiàn)翻譯
- 畢業(yè)論文市場營銷外文文獻(xiàn)翻譯
- 采購招標(biāo)流程畢業(yè)論文外文文獻(xiàn)翻譯
- plc畢業(yè)論文_的外文文獻(xiàn)(和翻譯)
- java編程思想-畢業(yè)論文外文文獻(xiàn)翻譯
- 化學(xué)專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯.pdf
- 化學(xué)專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯.pdf
- 單片機(jī)方面畢業(yè)論文_外文文獻(xiàn)翻譯
- 自動(dòng)化專業(yè)畢業(yè)論文外文文獻(xiàn)翻譯
- 數(shù)據(jù)通信畢業(yè)論文外文文獻(xiàn)翻譯
- 會(huì)計(jì)學(xué)畢業(yè)論文外文文獻(xiàn)及翻譯
- 財(cái)務(wù)管理畢業(yè)論文外文文獻(xiàn)及翻譯
- 機(jī)械類畢業(yè)論文外文文獻(xiàn)資料翻譯
- 審計(jì)學(xué)畢業(yè)論文外文文獻(xiàn)及翻譯1
- 洗衣機(jī)washingmachines-畢業(yè)論文外文文獻(xiàn)翻譯
評(píng)論
0/150
提交評(píng)論