高速铁路大断面黄土隧道施工数值模拟

二○****届毕业设计高速铁路大断面黄土隧道施工数值模拟学院：******专业：******姓名：********学号：**********指导教师：********完成时间：20**年6月10号二〇****年六月毕业论文报告摘要郑州至西安的客运专线为国内首批拟建的高速客运专线，该线位于中国黄土分布的中心地带，全线穿过黄土段的隧道累计里程长达65km。黄土因其具有特殊的成分和性质而在工程地质中占据特殊的地位，其工程特征表现出与普通岩石隧道相当大的差异，郑州至西安铁路客运专线黄土隧道特征最具典型性,围岩属V级Q3新黄土。该线隧道均为双线隧道，开挖面积达174m2，是目前国内开挖断面最大的黄土隧道。本文总结了大断面黄土隧道的研究现状及存在的主要问题，分析了隧道断面分类、高速铁路隧道的技术特点、黄土隧道工程特性、黄土地基沉降及其加固的理论，并在综合分析当前大断面黄土隧道发展的基础上，依托郑西客运专线凤凰岭黄土隧道工程背景，以解决高速铁路大断面黄土隧道关键施工技术为出发点，应用大型通用有限元软件ANSYS为计算手段，对湿陷性黄土隧道全断面施工方法和弧形导坑法的安全性进行了对比的分析和研究，得出了一些结论和建议。关键词：大断面，黄土隧道，弧形导坑法，数值模拟毕业论文报告ABSTRACTThefirstbatchdomesticproposedhigh-speedpassengerdedicatedlineisfromZhengzhoutoXi'an.Thelineislocatedinthecenterofloessdistribution,andthewholelineacrosstheloesssectionisalmost65km.Becauseofitsspecialcompositionandproperties,loessoccupiesaspecialplaceintheengineeringgeology,andtheengineeringfeaturesshowconsiderabledifferencewithordinaryrocktunnel.ThelinefromZhengzhoutoXi'anfeaturesthemosttypicalloesstunnel,andthesurroundingrockgradeVnewQ3loess.Thislineisbasedondoublelinetunnel,andthetunnelexcavationareaof174m2isthedomesticlargestloesstunnelexcavationsection,whichisunprecedentedinChina,andthereisnoexperienceforreferencetotheconstructionofthistunnel.Inthispaper,Ididsomeresearchofthepresentsituationandmainproblemsoftheloesstunneloflargesectionandclassificationoftunnelcrosssection,thetechnicalfeaturesofhigh-speedrailwaytunnel,theengineeringpropertiesofloesstunnel,loessfoundationsettlementandconsolidationtheory.Basedonthecomprehensiveanalysisonthebasisofthecurrentdevelopmentinloesstunneloflargesection,relyingonthisloesstunnelengineeringbackground,inordertosolvethekeyconstructiontechnologyinloesstunneloflargesectionofhighspeedrailway,usinglarge-scalegeneralfiniteelementsoftwareANSYSasthecalculatingmethod,analyzingandresearchingthearcheadingconstructionsafetyperformance,Iworkoutsomeconclusionsandsuggestions.KEYWORDS:largecrosssection,loesstunnel,numericalsimulation,arcpilottunnelmethod毕业论文报告目录第一章绪论................................................................................................................11.1黄土隧道研究的背景及意义..........................................................................11.2国内外黄土隧道研究现状及存在的问题......................................................11.3本文研究内容与方法......................................................................................5第二章高速铁路黄土隧道相关特性介绍................................................................72.1隧道断面分类..................................................................................................72.2高速铁路隧道施工特点..................................................................................72.3黄土工程特性..................................................................................................92.4黄土地基沉降问题描述................................................................................102.4.1黄土的湿陷性质..................................................................................102.4.2黄土的湿陷性评价..............................................................................102.4.3黄土隧道地基的湿陷性问题..............................................................112.5黄土地基加固处理方法................................................................................122.6复合地基现有沉降理论与方法....................................................................12第三章数值模拟方法简介......................................................................................143.1有限元的基本思想和优点............................................................................143.2有限元数值模拟过程....................................................................................143.3Ansys软件介绍.............................................................................................163.4Ansys软件平面弹塑性分析过程.................................................................173.4.1计算假定..............................................................................................173.4.2弹塑性分析选项设置..........................................................................183.4.3单元的生死..........................................................................................20第四章高速铁路大断面黄土隧道施工数值模拟分析..........................................224.1凤凰岭隧道工况............................................................................................224.2建立模型........................................................................................................224.2.1弧形导坑法..........................................................................................244.2.2全断面开挖..........................................................................................254.3分部开挖........................................................................................................254.3.1弧形导坑法..........................................................................................254.3.2全断面开挖..........................................................................................324.4模拟结果及分析............................................................................................354.4.1弧形导坑法...........................