盾构泡沫发生系统毕业设计论文

目录第1章绪论111盾构机的发展历史112我国盾构技术的应用现状及发展趋势2121应用现状2122发展趋势313盾构技术的工作原理及其特点4131盾构技术基本概念4132盾构技术基本原理4133盾构技术施工的基本特点414研究内容515本章小结5第2章泡沫系统原理及施工控制621泡沫系统简介622泡沫注入工法6221泡沫注入法工法的特点6222适用范围和使用材料7223泡沫改良土体的机理研究8224适合使用泡沫改良的地层923泡沫加注系统10231泡沫加注系统的组成10232泡沫系统工作原理1024本章小结13第3章参数计算及选型1431泡沫系统参数的计算1432硬件的选型16321泡沫剂泵的选择16322水泵的选择18323空压机的选择19324管路的选择19325各支路的阀、管接头、传感器及指示仪表等的选择2033泡沫发生器的设计23331泡沫发生特性23332泡沫发生器主参数的确定2434本章小结27第4章盾构发展与展望2841结论2842展望28421盾构的发展方向28422我国盾构市场前景2943本章小结30参考文献31致谢32附录外文翻译33第1章绪论11盾构机的发展历史1818年MARCISAMBARDBRUNEL获得隧道盾构法施工的专利，并在1825年到1843年间首次使用盾构在伦敦的泰晤士河下修建了一条河底隧道，初步证明盾构法隧道施工的价值。1830年由劳德考克让施（LORDCOCHRANCE）发明了施加压缩空气防止涌水的“气压法”。1874年格雷蒙特（JAMESHENRYGREATHEAD）在伦敦地铁南线的隧道建设中采用了气压盾构法的施工工艺，并首创了在盾尾后面的衬砌外围环形空隙中压浆的施工方法，并开发了用流体支撑开挖面的盾构，开挖出的弃土以泥水流的方式排出。1896年HAAG在柏林第一次申请了德国泥水式盾构的专利，形成了现代泥水式盾构的雏形，推动了盾构施工技术的发展。到20世纪初，盾构施工法在英、美、德、俄、法、日等国开始推广。1917年日本开始在铁羽越线的折返段隧道施工中引进盾构法，1938年正式在国铁关门隧道应用盾构法施工，为日本盾构技术的发展奠定了基础。1967年由英国提出的泥水加压系统在日本得到了实施，日本研制成功第一台有切削刀盘、水力出土的泥水加压式盾构（直径为31M）。1974年日本独创性地研制成功土压平衡盾构，同时德国WAYSSLTSANALYSISSHOWTHATTHEFOAMHELPSTOIMPROVETHEMACHINEDRILLINGPERFORMANCESINSANDS,BUTITSUSEFULNESSWITHAGGREGA,ESISLIMITED1998PUBLISHEDBYELSEVIERSCIENCELTDALLRIGHTSRESERVED1INTRODUCTIONTHEREALIZATIONOFUNDERGROUNDWORKSINSOFTANDWATERBEARINGGROUNDSANDTHEINCREASINGCONCERNWITHTHEENVIRC,NMENTSEEMSTOFAVORTHEUSEOFEARTHPRESSUREBALANCEDEPBSHIELDSINORDERTOEXPANDTHEFIELDOFUSEOFTHISTECHNOLOGY,WHICHWASORIGINALLYDESIGNEDFORUSEINCOHESIVESOILSWITHLOWPLASTICITY,SOMERESEARCHHASLEDTOTHEDEVELOPMENTOFADDITIVESPRODUCTS,INCLUDINGCHEMICALFOAMNISHITAKEETAL1993,REDA1994,ISHIMOTOETAL1995DESPITETHESUCCESSOFTHEEPBSHIELD,SOMEQUESTIONSREMAINABOUTTHISTECHNOLOGY,ASEVIDENCEDBYTHERECENTLAUNCHINGOFTWOFRENCHRESEARCHPROJECTS,EUPALINOS2000ANDMICROTUNNELSEXPERIMENTATIONONAMICROTUNNELINGSITEUSINGFOAMINJECTIONIN1992POINTEDOUTTHENECESSITYFORTHETESTSTOBECONTINUEDQUEBAUD1992FIRST,AMETHODOLOGYOFRESEARCHOFTHEBESTPRODUCTSABLETORESPONDTOTHEWORKINGREQUIREMENTSOFAMACHINEINAGIVENSOILWASDEFINEDITWASTHENDIVIDEDINTOTHREESTEPSFSTT1993成套设计购买WWWLUNWENDZCOM毕业设计代做WWWLUNWEN168NET开题报告WWWKTJIACOMABBREVIATION/EXPLANATIONOFTERMSABBREVIATIONEXPLANATIONOFTERMSKAEXPANSIONRATIOOFFOAMMESUREDUNDERTHEATMOSPHERICPRESSUREKEXPANSIONRATIOOFFOAMMESUREDUNDERADEFINEDPRESSUREPAATMOSPHERICPRESSUREMPAPDEFINEDPRESSUREEARTHPRESSUREMPAPGMGENERATIONPRESSUREOFFOAMMPATIFOAMINJECTIONRATIOCOAMCONSUMPTIONOFFOAMINGAGENTG/M3OFEXCAVATEDSOILKPERMEABILITYOFTHEFOAMEDSOILM/SCAMCONCENTRATIONOFFOAMINGAGENTGPPOWERREDUCTIONMIXINGTESTWWATERCONTENTOFTHESOILS1FINESILICEOUSSANDS2SILICEOUSSANDG1SILICEOUSAGGREGATESG1AGGREGATEMIXTUREOF2ANDG1TENSIO1FOAMINGAGENTTENSIO2FOAMINGAGENT1THESTUDYOFTHEPRODUCTSUSEDFORTHEFOAMGENERATION,ASWELLASTHEFOAMCHARACTERISTICS2THEPREPARATIONOFSPECIFICATIONSOFTHECHARACTERISTICSREQUIREDBYTHEEXCAVATEDSOILINORDERTOOPTIMIZETHEWORKINGOFANEPBSHIELD3THEDESIGNOFSIMPLETESTSFORTHEFOAMCHARACTERIZATIONBUT,ABOVEALL,FORTHESTUDYOFTHEFOAMEDSOILALABORATORYTESTSCAMPAIGNWASTHENCARRIEDOUTWITHTYPICALSOILSINORDERTOSTUDYTHEDIFFERENTPROBLEMSWHICHOCCURDURINGTHEEXCAVATIONTHERESEARCHCAMPAIGNRESULTSAREGIVENHEREAFTERQUEBAUD19962THEFOAMSTUDY成套设计购买WWWLUNWENDZCOM毕业设计代做WWWLUNWEN168NET开题报告WWWKTJIACOMALTHOUGHTHEINDUSTRIALAPPLICATIONSOFFOAMAREVARIOUS,ITSUSEINUNDERGROUNDWORKSHASBEENCONCENTRATEDINTWOFIELDSCELLULARCONCRETEANDDRILLINGOPERATIONSVENUAT1984,MYERS1992THECHEMICALPRODUCTSUSEDTOPRODUCEFOAMARECALLEDSURFACTANTSORSURFACEACTIVEAGENTSTHESEPRODUCTSHAVETHEDISTINCTIVECHARACTERISTICOFMODIFYINGTHESOLUTION/AIRINTERACTIONSWHENTHEYAREINWATERMARCOU1990THEFOAMCANBEDEFINEDASAPHYSICALSTATEINWHICHAGASEOUSPHASEISDISPERSEDINBUBBLEFORMINASECONDLIQUIDPHASETHEMAINPARAMETERSDESCRIBINGAFOAMAREFOAMINGABILITY,THATIS,THEAMOUNTOFFOAMPRODUCEDWITHACERTAINQUANTITYOFLIQUIDUNDERSOMEKNOWNCONDITIONSPERSISTENCE,WHICHISITSCAPACITYTOMAINTAINACONSTANTVOLUMEANDKEEPTHELIQUIDOFTHEMATRIXFROMFLOWINGOUTTHEDEGREEOFFOAMDISPERSION,MAINLYCHARACTERIZEDBYTHEAVERAGEBUBBLESIZEANOTHERPARAMETERISQUITEIMPORTANTFORTHEFOAMSPRODUCEDINDUSTRIALLYTHEIREXPANSIONRATIO,K,EQUALTOTHEVOLUMEOFFOAMPRODUCEDDIVIDEDBYTHEINITIALVOLUMEOFLIQUIDANUMBEROFFACTORSCANINFLUENCETHEFOAMCHARACTERISTICS,SUCHASTHESURFACTANTCONCENTRATIONANDTHEUSEOFADMIXTURES,WHICHACTONFOAMABILITYANDPERSISTENCEFOAMINGORANTIFOAMINGPRODUCTSTHECOMPRESSIBILITYOFFOAMISIMPORTANT,TOOBECAUSETHEFOAMISINJECTEDINACONFINEDMIDDLEEARTHPRESSURE,ITISNECESSARYTOKNOWITSBEHAVIOURUNDERPRESSUREWITHKTHEEXPANSIONRATIOAMEASUREDUNDERTHEATMOSPHERICPRESSUREP,WECANWRITETHATFORAPRESSUREP11AAAKPPK3ACTIONOFFOAMONEXCAVATEDSOILTHESOILEXCAVATEDBYANEPBSHIELDMUSTHAVESOMECHARACTERISTICSWHICHOPTIMIZETHEMACHINESOPERATIONDEPENDINGONTHENATUREOFTHESOIL,ITMAYBENECESSARYTOMIXITWITHSOMEFOAMINORDERTOMODIFYITSORIGINALCHARACTERISTICSATTHEBEGINNING,THISSHIELDWASUSEDINSOFTGROUNDSLIKESILTSORSOFTCLAYS,WITHASATISFACTORYWATERCONTENTOTHERTYPESOFSOILPRESENTDIFFERENTPROBLEMS,EGSTICKINGANDPLUGGINGFORHARDCLAYS,LACKOFPLASTICFLUIDITYANDHIGHPERMEABILITYFORGRANULARSOILSTHEPASTEOBTAINEDBYTHEMIXINGOFEXCAVATEDSOILANDFOAMMUSTBECLOSETOTHEPLASTICSTATECALLEDTHEPSEUDOFLUIDORPSEUDOPLASTICSTATE,MUSTBEIMPERMEABLE,ANDMUST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