复合土钉墙支护毕业设计

2014届本科毕业设计某基坑复合土钉墙支护设计学院土木工程学院专业班级学号学生姓名指导老师提交日期2014年6月5日安徽建筑大学本科毕业设计I摘要基坑工程是指在地表以下开挖的一个地下空间及其配套的支护体系。而基坑支护就是为保证基坑开挖，基础施工的顺利进行及基坑周边环境的安全，对基坑侧壁以及周边环境采用的支挡，加固与保护措施。基坑支护体系是临时结构，安全储备较小，具有较大风险，基坑工程具有很强的区域性。不同水文，工程地质环境条件下基坑工程的差异很大。基坑工程环境效应复杂，基坑开挖不仅要保证基坑本身的安全稳定，而且要有效的控制基坑周边地层移动以及保护周围环境。本文介绍了安徽裕鹏房地产开发公司拟建金云国际小区，其中高层建筑5幢，23～28层，框剪结构；6层建筑5幢，框架结构；以及地下车库（地下一层），埋深在现地面下约3～4米。总建筑面积约12.1万㎡。本设计主要对此基坑支护方案论证选择和支护设计计算。拟建建筑场地基坑长约270m，宽约150m，开挖深度为8m。根据场地工程地质条件，可以采用水泥土重力式挡墙、钻孔灌注桩、地下连续墙、复合土钉墙等支护设计。由于土钉墙支护作为一种较常用的支护形式，凭借其工期短、造价低的优势异军突起，因此为了满足基坑的安全、经济、合理等问题，本设计最终确定采用复合土钉墙支护设计，即土钉墙与有限放坡有机组合成的复合支护体系。关键词：基坑支护；方案选择；设计计算；复合土钉墙安徽建筑大学本科毕业设计IIABSTRACTExcavationmeansbelowthesurfaceofanexcavationofundergroundspaceandsupportingthesupportingsystem.Theexcavationistoensuretheexcavation,smoothandsafesurroundingsfoundationpitconstruction,excavationsidewallsforretainingandusingthesurroundingenvironment,reinforcementandprotectionmeasures.FoundationBracingSystemisatemporarystructure,asmallersafetymargin;withagreaterriskofexcavationhasastrongculture.Differenthydrological,geologicaldifferencesintheenvironmentalconditionsunderexcavationworksgreat.Environmentaleffectsofcomplexexcavation,excavationpititselfnotonlytoensuresecurityandstability,butalsotoeffectivelycontrolthepitsurroundingstratamovementandprotectthesurroundingenvironment.ThisarticledescribestherealestatedevelopmentcompanyinAnhuiYuPengJinYunproposedinternationalcommunity,includingfivehigh-risebuildings,23to28floors,wallstructure;fivesix-storeybuilding,theframestructure;andundergroundgarage(basement),burieddeepinthecurrentofabout3to4metersundertheground.Thetotalconstructionareaofabout121,000squaremeters.Thedesignofthemainargumentsinthisexcavationprogramselectionandsupportdesigncalculations.Theproposedconstructionsiteexcavationlength270m,width150m,excavationdepthof8m.Accordingtothesiteengineeringgeologicalconditions,soilcementcanbeusedgravityretainingwall,boredpiles,diaphragmwalls,wallsandothercompositesoilnailingsupportdesign.Becauseofsoilnailingwallismorecommonlyusedasasupportform,byvirtueofitsshortduration,thesuddenemergenceoflowcostadvantage,soinordertomeetthesecuritypit,economic,rationalandotherissues,finalizethedesignofcompositesoilnailingwallssupportdesign,namelysoilnailwallunitswithlimitedgradinghavesynthesizedcompositesupportsystem.Keywords：excavation;selectprogram;designcalculations;compositesoilnailingwalls安徽建筑大学本科毕业设计III目录摘要..............................................................IABSTRACT........................................................II第1章绪论........................................................11.1基坑工程的特点及发展意义.....................................11.1.1基坑工程的特点.................................................11.1.2基坑工程的发展意义.............................................21.2复合土钉墙支护技术理论.......................................21.2.1极限平衡法.....................................................21.2.2有限元法.......................................................31.2.3工程简化分析法.................................................31.2.4试验研究分析法.................................................41.3复合土钉墙支护技术现状.......................................51.4复合土钉墙支护类型...........................................51.4.1土钉与桩锚复合支护.............................................61.4.2土钉与预应力锚杆复合支护.......................................61.4.3土钉与止水帷幕复合支护.........................................71.4.4土钉与止水帷幕、预应力锚杆复合支护.............................71.4.5土钉与微型桩复合支护...........................................71.5本设计的主要内容.............................................91.5.1收集资料.......................................................91.5.2方案选型.......................................................91.5.3支护技术计算..................................................10第2章基坑支护方案选型...........................................112.1工程概况....................................................112.2工程地质条件................................................112.2.1场地位置及地形地貌............................................112.2.2地基岩土构成及岩性特征........................................112.2.3地下水........................................................122.3场地及地基条件综合评价......................................122.3.1场地的稳定性..................................................122.3.2场地和地基的地震效应..........................................122.3.3天然地基设计参数..............................................122.3.4地基土的胀缩性................................................13安徽建筑大学本科毕业设计IV2.4岩土工程参数选取............................................132.5常见的基坑支护形式及比较....................................132.5.1深层搅拌水泥土围护墙..........................................132.5.2钻孔灌注桩....................................................132.5.3地下连续墙....................................................142.5.4SMW工法桩....................................................142.5.5土钉墙........................................................142.6复合土钉支护作用机理分析....................................152.6.1分担荷载作用..................................................152.6.2止水抗渗作用..................................................162.6.3传递荷载作用