第23卷第3期2006年9月建筑科学与工程学报JournalofArchitectureandCivilEngineeringVol.23No.3Sept.2006文章编号:1673-2049(2006)03-0071-05秦岭终南山特长公路隧道大埋深段施工监测及分析陈建勋‘,杨忠2袁雪截2(1.长安大学桥梁与隧道陕西省重点实验室,陕西西安710064;.陕西秦岭终南山公路隧道有限责任公司,陕西西安710054)摘要:为了探讨在大理深、软弱围岩条件下,隧道围岩变形、围岩压应力和支护结构的力学特征,采用SWJ-N型收敛计、振弦式土压力盒等测试元件,对秦岭终南山特长公路隧道埋深大于1200m的lu类围岩地段,进行了净空收敛变形、围岩压应力、喷射混凝土应力、钢架应变、锚杆轴力等监控量测。结果表明,即使是在初期支护作用下,净空收敛的量值和速率在测试初期也是很大的;初期支护受力很大,特别是钢架内、外缘均处于受压状态,而且钢架大部分均超过钢材的屈服极限,钢架处于失稳状态;采用116型钢钢架(间距1福"m-'),3.5m锚杆和20cm喷射混凝土支护,其支护强度是不够的,应采取减小型钢钢架间距「改为3棍"(2m)一‘〕等措施予以加强;施工中喷射混凝土必须及时、饱满,才能保证描喷网钢架共同作用,否则会引起钢架变形很大,甚至导致塌方事故的发生。关键词:特长公路隧道;大埋深;监控量测;钢架;变形中图分类号:U451.2文献标志码:AConstructionDepthMonitoringandMeasuringinSegmentsofLargeEmbeddedinQinlingZhongnanshanSuper-LongHighwayTunnelCHENJian-xun',YANGZhong2,YUANXue-kan2(1.KeyLaboratoryforBridgeandTunnelofShaanxiProvince,Chang'anUniversity,Xi'an710064,Shaanxi,China;2.ShaanxiQinlingZhongnanshanHighwayTunnelLtd,Xi'an710054,Shaanxi,China)Abstract:Todiscussthemechanicalcharacteristicsoftunnelsurroundingrockdistortion,surroundingrockpressurestressandsupportingstructurewhentunnelwasundertheconditionsoflargeembeddeddepthandweaksurroundingrock,authorstooksometestingorgans,suchasSWJ-1Vtypeconvergenceindicator,vibrationalchordtypesoilpressurecell,etc.InMclasssurroundingrocksegmentswithembeddeddepthmorethan1200minQinlingZhongnanshansuper-longhighwaytunnel,thosemonitoringandmeasuringasnetconvergencedistortion,surroundingrockpressurestress,sprayedconcretestress,steelframestrainandaxialforceofanchorbarweremade.Theresultsshowthattunnelinconditionsoflargeembeddeddepthandweaksurroundingrockcanproducelargedistortion,evenifontheeffectofprimarysupport,themeasuredvalueandspeedofconvergencearestilllarge;thestressinprimarysupportisverylargeespeciallyinprofiledbarsteelframe,theinnerandoutsideedgeofsteelframeareinstressconditionandmoststeelframestressesexceedsteel负eldlimit,thesteelstressinunstable收稿日期:2006-0s-10墓金项目:陕西省交通科技项目(02-21K)作者简介:陈建勋(1969-),男,陕西韩城人,副教授,工学博士研究生,E-mail:chenjx1969@163.como建筑科学与工程学报2006年condition;thesupportlike116profiledbarsteelframe(spacebetween1set·m-'),3.5mlengthrockboltsand20cmdepthsprayedconcretearenotenoughinthatsegments;thesupportingstrengthshouldbeconsolidatedthroughsomemeasures,suchasreducingthespacebetweensteelframe[reduceto3set·(2m)一‘〕andsoon;sprayedconcreteshouldbemadeintimeandfullinconstruction,thenitcanensurerockbolts,sprayedconcrete,barmatreinforcementandsteelframeinchorus,ifnot,thedistortionofsteelframewouldbelargeandcollapseaccidentsmayhappenindeed.Keywords:super-longhighwaytunnel;frame;distortionlargeembeddeddepth;monitoringandmeasuring;steel0引言秦岭终南山特长公路隧道是西安至安康高速公路穿越秦岭山脉的一条越岭隧道,全长18.02km,双洞四车道,中线间距30m,属世界规模第一、长度第二的山岭公路隧道。隧道洞身横穿秦岭东西向构造带,该带经历了多期构造运动、变质运动和混合岩...