六车道大跨浅埋双连拱隧道施工工法

'目录一、前言1二、工法特点3三、适用范围3四、工法原理及关键技术3五、工艺流程及操作要点4（一）工艺流程41、三导洞施工法（见图2）42、中导洞＋分部开挖法（见图3）53、施工工艺流程（见图4）5（二）操作要点61、洞口工程施工准备62、长管棚施工63、反压回填土及地表导管注浆74、中导洞开挖85、侧导洞开挖86、中隔墙施工（参见图6）87、正洞施工98、支护体系施工99、防排水体系1010、二次衬砌施工1011、监控量测11六、机具设备13七、劳动力组织13八、质量控制14九、安全措施14十、效益分析14十一、工程实例15pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 六车道大跨浅埋双连拱隧道施工工法林永强　崔根群　辛国平　陈锐（中铁隧道集团有限公司第一工程处）一、前言双连拱隧道是在高速公路通过山势不高、长度较短、上下行线在此分离不开的地段设置双跨连拱隧道，具有易于选线、节约用地、有利环保等优点，但造价一般较高。随着我国的高等级公路的迅猛发展，在建或拟建的众多高速公路均已按六车道进行规划设计或预留，特别是在山区面积所占比例大、地形条件复杂的山岭重丘地区（如我国的中西部）将出现越来越多的六车道大跨双联拱隧道。如：上海至武威国家重点公路河南境南阳内乡至西坪段（宛坪高速）连续出现了16座六车道双连拱隧道，国内十分罕见。其隧道单跨断面为多心圆结构，边墙为曲墙，中墙为直墙，单跨净宽14.1m，净高8.2m，左右洞之间通过2.4m厚的钢筋砼中隔墙相连，初期支护采用工字钢拱架、中空注浆锚杆、挂钢筋网、喷砼等形式，二衬采用独特的“夹心式”模筑双层钢筋砼结构（参见图1）。图1六车道大跨连拱隧道断面结构图十六座隧道均具有以下几个特点：1、浅埋、地质条件复杂：因隧道通过的地段一般山势较低，最大埋深在40至80米之间，围岩风化严重、软弱破碎，节理发育，地表水直接影响隧道内涌水量。2、跨度大：开挖跨度达32.6m，使得中隔墙将承担比一般连拱隧道更大的压力，中隔墙更容易下沉。3、偏压：由于跨度大，左右洞的埋深不同，整条隧道存在不同程度的偏压，特别是洞口段偏压比较严重，造成进洞困难。pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 4、施工工序复杂：大跨双连拱隧道的施工必须分多工序多步骤进行，各个工序间相互影响大，施工组织要求科学合理。5、防水困难：连拱隧道中隔墙顶漏水是一个通病，采用“夹心式”衬砌结构科学解决了中隔墙防水层施作问题，但由于跨度大，中隔墙部位的水量更加集中、水压大，对防水层的要求高，必须精细施工。中铁隧道集团在其中三座隧道的施工中，根据六车道双连拱隧道埋深浅、跨度大的特点，通过科学的施工组织，采用三导洞法及分部开挖法，结合超前管棚、地表反压回填、地表预注浆等辅助措施，以监控量测为指导，不断优化施工方案进行动态管理，安全快速地通过强风化细砂岩层夹薄层泥岩，成功解决了中隔墙下沉开裂、中隔墙渗漏水的质量通病，遥遥领先其它隧道率先完成施工任务。为此，通过对三座隧道的施工工艺，包括进洞方案、开挖方法、衬砌施工、特殊问题的处理等方面进行总结，形成了本工法。二、工法特点1、采用稳妥合理的进洞方案：合理安排中导洞提前正洞6～7m进洞，同时进行左右正洞的超前大管棚、地表反压回填、地表预注浆等辅助措施，同时施工互不干扰，有利于进洞安全并缩短工期1个月。2、中导洞先行，侧导洞跟进，三导洞同行不同步的施工组织安排，实现安全快速施工。3、Ⅳ级以上围岩地段采用中导洞法，取消侧导洞，正洞采用分部开挖法，减少临时支护投入，施工经济高效。4、按“管超前、短进尺、弱爆破、强支护、早封闭、勤量测”方针组织施工，特别注重钢支撑及锁脚锚杆作用，确保隧道安全。5、无钉热熔铺设防水板技术，做到隧道不渗不漏水。三、适用范围1、开挖横跨度≤32.0m，高度≤11.1m，围岩类别为Ⅳ～Ⅵ级的公路六车道双连拱隧道。2、四车道公路连拱隧道。3、其它类似的地下工程可参照进行应用和推广。四、工法原理及关键技术pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 （一）工法原理1、根据隧道“早进晚出”原则，避免大挖大刷，隧道尽可能提前进洞，洞顶覆盖层达2m时便可进洞。进洞前，采取φ89（或108）超前大管硼、地表返压回填、地表预注浆等一些必要措施提前加固洞口。2、根据六车道大跨连拱隧道的结构特点，尽快优先贯通中导洞，尽早施作中隔墙，为左右正洞的开挖创造条件。为此，中导洞尽可能提前进洞，采用台阶法或全断面法开挖，汽车配合装载机出碴，快速掘进。3、中导洞贯通后，先行浇筑中隔墙基础，墙身采用两片整体式钢模板台车一次性模注完成。4、左右正洞的洞口浅埋段及Ⅴ级围岩段采用侧壁导洞法施工，Ⅳ级围岩以上取消侧导洞，采用环形开挖分部法施工。5、仰拱紧跟掌子面下部，起到早封闭作用，并尽早施作二衬。确保洞口安全，明洞衬砌先行施工，左右明洞采用两台液压模板台车并排、对称整体浇注。6、开挖支护严格按新奥法原理组织施工。7、合理组织各工作面人员与机械，资源优化组合。（二）关键技术1、中隔墙的防开裂、抗偏压及防下沉技术。2、各导洞之间及左右正洞之间错开距离的合理确定。3、预留变形量的合理确定。4、防排水层的施工工艺技术。五、工艺流程及操作要点（一）工艺流程1、Ⅴ级围岩段采用三导洞法（见图2）①中导洞台阶法（或全断面）开挖、临时支护②侧导洞台阶法开挖、临时支护Ⅲ模注中隔墙基础及墙身，并回填下部及安装横向支撑④中墙顶部空洞注水泥砂浆⑤超前支护⑥正洞上部开挖及初期支护pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 ⑦正洞中部开挖⑧正洞下部仰拱开挖及初期支护、仰拱填充Ⅸ全断面模注二次衬砌钢筋砼2、Ⅳ级围岩采用中导洞法（见图3）①中导洞台阶法（或全断面）开挖、临时支护Ⅱ模注中隔墙基础及墙身，并回填下部及安装横向支撑（假设左侧正洞浅埋先行开挖，横支撑安在右侧，反之安在左侧）③中墙顶部空洞注水泥砂浆④超前支护⑤上部弧形导坑开挖、初期支护⑥中部核心土开挖⑦侧部开挖、初期支护⑧下部仰拱一次性开挖支护、仰拱填充Ⅸ全断面模注二次衬砌钢筋砼pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 3、施工工艺流程（见图4）中导洞开挖支护模注中隔墙基础、墙身砼中隔墙基础回填土、安装横支撑中隔墙顶部空洞注浆处理左右侧导洞开挖支护浅埋侧正洞上部开挖支护另一侧正洞上部开挖支护正洞中部开挖正洞下部仰拱开挖支护、拆除临时支撑仰拱及填充全断面模注二次衬砌钢筋砼地表返压回填及注浆施工准备洞口长管棚施工管棚准备遇有偏压现象时进洞6m开挖8m图4大跨连拱隧道施工工艺流程图（二）操作要点1、洞口工程施工准备测量出左右线的洞口纵断面，按“早进晚出”原则，比选最佳进洞口位置。开挖出洞口管棚施工平台，并对边仰坡进行喷锚支护，做好洞顶排水系统。2、长管棚施工（1）设计参数：采用长为20～40m的Ф89（或108）超前大管棚支护，钢管为热轧无缝钢管，节长8米，环向间距40cm，外插角3°；（2）设置位置：明洞衬砌轮廓线以外30cm，中导洞顶及左右正洞上部60°范围。（3）导向墙（套拱）：厚60～80cm，长1.5～2m，采用I20钢拱架，C25混凝土pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 (模注砼或喷射砼)，左右侧导向墙在中导洞顶部应相连，成“m”形状。导向墙两端延伸至墙脚，设在稳定的基础之上，导向墙中部与提前进洞的中导洞初期支护相连，将中间悬空部分托起,形成稳定结构。（4）施工技术要点a.洞口预留核心土，经人工整修、夯实，使其表面圆顺，铺设3mm厚的钢板，作为导向墙混凝土施工的内模；导向管的位置及方向精确定位。b.每节钢管用丝扣连接，同一断面内接头数量不超过50%，相邻钢管的接头相错量不小于1m，施工时，把孔编为奇数和偶数，奇数孔钢管组合方式为8+8+4m，偶数孔钢管组合方式为4+8+8m。c.采用MK-5型液压钻机，钻机操作平台必须牢固、安全，架立钻机时应精确核定孔位，保证钻机钻杆线与管棚设计轴线吻合以及钻机在钻进过程中不发生偏移和倾斜。钻完一孔立即顶进钢管，管口处设置排气管，钢管与孔口处的间隙用麻团堵塞紧密，保证注浆时浆液不溢出。d.采用液压注浆机注浆，水灰比为0.5：1～2：1，注浆压力为0.8MPa～1.2Mpa，注浆过程中专人负责检查注浆效果，并作好记录。3、反压回填土及地表导管注浆隧道洞口段埋深浅，多为坡积物和人工弃土覆盖，存在偏压，自承能力差，存在坍塌、冒顶隐患；采用反压回填土增加浅埋侧覆盖层厚度以减少偏压，同时进行地表注浆固结围岩和上覆层，使原为主动荷载的上覆层变成能承载的承载拱,同时达到固结堵水的目的,以保证安全进洞。（参见图5）pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 （1）反压回填施工回填前先挖去软弱土，清除表土、灌木及危石；采用土石回填，用推土机和5T自卸汽车推运土石混合料，用18T振动压路机分层压实（每层压实厚25cm，压实度95%）。（2）小导管地表注浆注浆钻孔直径：Φ50（壁厚5mm）；注浆孔间距：150×150cm，梅花型布置；浆液：地表至拱顶压注1：1水泥砂浆；注浆终压：1.0Mpa；压注范围：隧道开挖轮廓线以外2米的所有反压回填段。4、中导洞开挖Ⅴ～Ⅵ级围岩段采用台阶法开挖，台阶长度5～6m，上下台阶均利用简易台架进行开挖支护作业，Ⅳ级围岩采用全断面开挖，断面开挖高度应比设计高出10cm，便于中隔墙立模。当为土质围岩时直接用挖掘机开挖，人工修整周边轮廓，必要时采用弱爆破。出碴采用汽车配合装载机。临时支护紧跟掌子面。5、侧导洞开挖侧导洞采用上下台阶法施工，施工方法同中导洞。因断面较小，侧导洞的出碴用装运机械倒运至洞外。偏压浅埋或围岩较差的侧导洞先行，并要滞后中导洞至少10m，另一侧导洞滞后先行侧导洞至少10m。当围岩情况比较好时，可以先只开挖上部，下部等正洞仰拱一起开挖。中导洞与侧导洞开挖中的地质情况应记录详尽，为正洞开挖作地质预报。6、中隔墙施工（参见图6）（1）施工安排中隔墙是连拱隧道的关键部位，也是施工的重点。在进洞条件允许的情况下，为缩短工期，中导洞开挖到一定里程后即可转入中隔墙施工，中导洞从另一端继续开挖，当开挖贯通时中隔墙也施工到贯通点，中导洞开挖人员即可转入正洞施工。由中导洞向正洞转换工序时中导洞开挖长度可按下式计算：K=L/（D/J+D/S+1）pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 式中：K-先施工端中导洞开挖长度m，L-中导洞全长m，D-中导洞开挖日进尺m/d，J-中隔墙基础砼施工日进尺m/d，S-中隔墙墙身砼施工日进尺m/d。（2）中隔墙基础a.采用大块拼装钢模板，泵送砼每循环浇注9m。b.为增加中隔墙的地基承载力及抗倾覆能力，基底浮碴必须清干净，并设地基锚杆（RD25N中空注浆锚杆）长3m，端头嵌入墙基50cm，间距100×75cm。c.基础两侧及时回填土石。（3）中隔墙墙身a.浇筑墙身前，在中导洞拱顶设径向RD25N中空注浆锚杆，长3m，间距100×75cm，外露50cm与墙顶相接，增强中隔墙的抗侧翻能力。b.采用整体式中隔墙衬砌台车，泵送砼每循环浇注9m。模板安装时，顶部预留出正洞初期支护的落脚平台，并预埋连接钢板。c.每隔4～5m顶部预留一根φ50mm注浆管，脱模后及时注1：1水泥砂浆，防脱空。d.假设左正洞准备先开挖，那么在中隔墙的右侧必须提前安装横向支撑，防止横向水平推力对墙体的破坏。一般浅埋偏压或围岩较差侧正洞先行施工，来确定支撑方向。7、正洞施工待中隔墙砼达到70%强度后，可进行正洞上部开挖施工。正洞分上中下三部开挖，上部采用环形开挖，超前5-6m，中部预留核心土，光面弱爆破，汽车配合装载机出碴。严格控制每循环进尺，浅埋段0.75m，Ⅴ级围岩深埋段1.5m，Ⅳ级围岩段2m，支护紧跟掌子面。左右洞宜同时开挖，但不能齐头并进，错开8～10米较合适，一方面相互影响小，另一方面对中隔墙产生的水平推力小。8、支护体系施工（1）超前小导管支护导管采用5m长Φ50×5热轧无缝钢管，环向间距40cm，搭接长度不小于100cm，外插角6°；采用YT28风钻沿隧道纵向以6°外插角钻孔，孔径稍大于管径(Φ65)。小导管尾部焊在钢拱架上，顶进时注意保护管口不变形，并对开挖面及相临界面喷砼封闭，管口设止浆塞。采用1：1水泥浆灌注，施工配合比经现场试验确定，注浆终压为0.5MPa～1.0MPa，能保持压力2min即表明达到注浆效果。（2）初期支护pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 采用工字钢拱架+“喷锚网喷”支护,Ⅴ级围岩段采用I25a工字钢，间距为0.75m，Ⅳ级围岩采用I20b工字钢，间距为1m，锚杆采用RD25N中空注浆锚杆，喷砼采用湿喷工艺。（初期支护施工工艺见流程图7）施工要点：爆破找顶初喷打锚杆立钢架挂网喷砼测量打眼注浆打小导管养生图7初期支护施工流程图a.确保钢拱架的加工质量。采用液压弯拱机加工，平面翘曲度控制在允许范围内，加工好的拱架先在平整的场地上预拼，检查合格批量加工、编号存放。b.钢拱架安装时，拱脚置于牢固的基础，连接钢板的螺栓必须拧紧，接钢板企缝焊接，确保整体拱架发挥承力作用。c.钢拱架之间用纵向钢筋连接。d.在拱脚处增设两根砂浆锚杆并与钢拱架焊接。9、防排水体系防排水结构采用夹心式，排水通路封闭成环，形成有效的排水系统。（参见图8）（1）隧道每5m环向布设Ω型弹簧排水半管与两侧墙脚处纵向排水花管（PVCφ100×4）相连，并用PVCφ100×4排水管与中心排水沟横向连通，形成纵横向连通的完整排水体系。（2）防水层采用复合式防水板（1.5mm厚改性LDPE防水板和450g/m2土工布），系吊带铺设，用热熔机焊缝（宽10cm）。防水板是否破损是防渗漏水的关键，必须处理好突出物(锚杆、小导管头),防电焊烧伤，逐条缝逐面积排查及时修补。（3）隧道内所有施工缝和变形缝均设置中埋式橡胶止水带。pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 10、二次衬砌施工（1）仰拱紧跟正洞下部，仰拱初期支护一次性对接成环，并及时进行仰拱填充。仰拱填充整体浇筑施工，洞内车辆从简易便桥上通过。（2）二次衬砌砼采用整体式模板台车。a.使用色拉油或新鲜机油作脱模剂。b.输送泵泵送入模，捣固棒配合附着式振动器捣固混凝土，混凝土对称分层浇注，边墙从墙脚往上压注，拱部从拱脚处压注，最后从拱顶低端处压注，杜绝混凝土自由跌落，防止产生空洞。c.拱顶设φ25钢管排气孔，并作为拱顶空洞注浆孔。d.隧道明洞中墙与拱圈为整体性结构，需用2个模板台车并排，一次性整体浇注。外模采用木摸，边墙侧模板加固采用钢拱架,用方木或圆钢管支撑加固；中隔墙顶的木模加固在砼外层钢筋上。由于明洞整体浇注的混凝土量大，特别是拱脚压力特别大，模板安装要确保牢固，避免跑模。明洞整体浇注施工参见图9。pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 11、监控量测（1）监控目的现场围岩监控量测是大跨连拱隧道十分关键的一环，通过监测及时对数据进行分析，判断变形是否稳定，指导施工，重点解决以下几个问题：a.动态地确定开挖与支护预留变形量；b.判断围岩类别情况，合理确定开挖方法，如正洞开挖采用双侧导洞法，还是分部开挖法；c.支护形式是否合理；d.断面超欠挖控制情况。（2）监测项目（见表1）表1主要监测项目及监测频率项目名称方法及工具布置监测频率地质和支护状况观察岩性、结构面产状及支护裂缝观察或描述,地质罗盘等开挖后及初期支护后即进行每次爆破后及初期支护之后洞口浅埋段地表下沉精密水准仪洞顶地表每10米一个横断面,每断面4～5m一个点刚进洞时1次/2天，进到深埋段后1次/周周边位移各种类型收敛计或测杆每20米一个断面,每断面2～3对测点头15天1次/天，16～30天1次/2天，1～2月1次/周，2个月以上1～3次/月拱顶下沉水平仪、水准尺、钢尺或测杆每20米一个断面与周边位移同时进行锚杆抗拨力锚杆拉拨仪每10米一个断面每个断面至少做三根锚杆断面测量断面仪、全站仪每5米一个断面每5米一个断面（3）测线和测点的布置（见图10、11）图10导洞测点、测线布置图pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 图11左右正洞测点、测线布置图（4）注意事项a.必须成立一个由2～3人组成的量测小组，专门负责。b.量测点在初期支护施作时安设，在下一循环开挖前完成，并测取初读数。c.测点应部安设在距开挖工作面2m范围内，且不大于一个循环进尺，并应细心保护，不受下一循环施工的破坏。d.各项位移的测点，一般布置在同一断面内，测点统一在一起，测设结果能互相印证，共同分析和应用。e.特别注意中导洞及测导洞的开挖施工地质记录，对正洞来说是最好的、最准确的超前地质预报方法，对其围岩情况应进行详细、准确的记录，指导正洞施工。六、机具设备主要施工机具配备（按一座单口开挖隧道计）见表2。表2主要机械设备一览表序号机械名称规格型号数量(台)备注1变压器S9-630/101电力设备2电动空压机LS-20HAC2开挖设备3挖掘机PC20014装载机ZLC40C15装载机ZLC50C16自卸载重汽车5t67风钻YT-28158风镐G10A69通风机DKJ-NO10210回转钻机MK-5D2支护设备pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 11砼喷射机湿式TK961312注浆机KBY-50/70313弯拱机0～250214电焊机BX-315-1415砼输送泵HBT602衬砌设备16砼运输车TSB-6317强制砼拌合机JS750218中隔墙模板台车9米119正洞液压模板台车9米2七、劳动力组织主要作业工序劳动力配备见表3。表3主要作业工序劳动力配备表工序工作内容人数×班数备注监控量测测量与量测7×1=7人测量组开挖支护开挖、初喷、立钢支撑、挂网、锚杆、复喷13×6=78人三导洞开挖班18×4=72人两正洞开挖班二次衬砌仰拱及填充8×2=16人仰拱施工班挂防水层、排水管4×2=8人防水板施工班钢筋绑扎、安装预埋件、台车定位25×2=50人钢筋衬砌班混凝土灌注、脱模、养生7×2=14人砼施工班八、质量控制严格执行《公路隧道施工规范》及《公路工程质量检验评定标准JTGF80/1-2004》，并在施工中注意以下事项：1、控制隧道超欠挖，初期支护紧贴围岩，防止初期支护背后出现空洞，超挖部位应回填密实；2、拱架安装时,控制好中线及标高，保持与中线垂直，避免钢拱架侵入二次衬砌，拱架之间联结牢靠，螺丝拧紧，必要时将连接钢板焊接牢固，拱脚要落在稳定基岩上,避免出现悬空,且必须设置锁脚锚杆；3、仰拱采用分左右幅开挖，基底清理干净，不满足承载力要求时换填片石砼；4、保证防水板无破损，保证排水管道的畅通；pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 5、模板台车加工刚度、尺寸、板缝、表面平整度等满足要求，减少错台，确保外观质量；6、明洞衬砌混凝土的方量大，注意模板加固牢靠，以免跑模。九、安全措施1、大跨连拱隧道断面大埋深浅，围岩情况复杂，坚持短进尺、早封闭，保证安全。2、洞口是隧道安全的关键，必须制定周密稳妥的进洞方案。3、左右洞加强调度协调，爆破时另一洞人员暂时撤离。4、下部开挖后仰拱及填充紧跟，尽快施作二次衬砌。5、坚持文明施工，注意洞内排水顺畅，避免水对拱脚、仰拱的浸泡；6、派专人负责监控量测，及时发现问题及时反馈信息，随时响应应急对策。十、效益分析1、施工进度加快：宛坪高速项目中，共计600米六车道大跨隧道，仅用时13个月便完成隧道主体工程施工，施工进度遥遥领先于其它标段。2、中隔墙采用整体式模板，与传统组合模板相比循环时间短，使正洞施工提前，整体工期缩短；Ⅳ级围岩地段优化施工方案，采用分部开挖法，取消侧导洞，节约投资203.8万元，经济效益明显。3、未出现坍方、砼开裂等安全、质量事故，在全线树立了良好形象，被业主做为典型指导全线隧道施工，多次受到河南省公路局、交通厅领导的高度评价，赢得了较好的社会效益。4、六车道大跨浅埋隧道目前还不是很多，但发展迅速。本工法克服了连拱隧道施工中隔墙开裂下沉、防渗漏水难题，做到隧道无一处漏水现象，实现了安全、经济快速修建大跨连拱隧道，对今后大跨度连拱隧道的设计施工具有指导作用。十一、工程实例河南省宛（南阳）－（西坪）坪高速公路是国家重点公路建设上海至武威国家重点干线公路的重要组成路段，全线总长150.297公里，共有六车道双连拱隧道16座，其中最长的隧道340米，最短的隧道105米，是我国目前六车道大跨双连拱隧道最多的一条高速公路。中铁隧道集团有限公司负责施工其中的2.5座隧道（吴家庄隧道340m，新沟隧道pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15 135m及樊营隧道进口段125m米的），共长600m，设计为双向六车道，计算行车速度120km/h，开挖跨度为32.37米，高12米，最小埋深1米，最大埋深68米，隧道穿越地层为全-强-弱风化白恶系上统细砂岩夹薄层泥岩，软弱相间岩组单斜构造，泥岩遇水软化，隧道开挖时，如受震动或处理不当会出现坍塌现象。因施工组织合理，方案得当，于2005年3月27日新沟隧道中导洞施工，到樊营隧道的二衬2006年5月30完工，用时13个月便完成了主体工程施工，遥遥领先于其它隧道。实际平均施工指标（包括雨天影响）：中导洞开挖76m/月，正洞开挖65m/月，二次衬砌86m/月，无一例安全质量事故。在全线其他13座连拱隧道中，因施工方法不当，共有3座隧道左右正洞口大坍塌，中隔墙开裂，1座隧道中导洞出现大坍方，7座隧道正洞开挖出现大小不等的塌方，工期安排到了2007年。而我集团公司施工的三座隧道在全线树立了样板，多次受到业主（宛坪高速公路有限公司）、省公路局、交通厅领导的好评，为我单位赢得了经济效益、社会效益的双丰收。pluguploopholesinmanagement.Themembersoftheleadershipteamtoinaccordancewiththeirrespectivefunctionsandduties,earnestlyimplementthegoodchargerangeofresponsibilityforproductionsafety,catchhiddeninvestigationandremediationascurrentahardtask,personallycheck,superviseandurgetherectificationinplace.ThecountyGovernmenttoimplementtoensurethatwithinthejurisdictionofallwalksoflifeofresponsibilityforproductionsafety,donotstaydead.TherelevantgovernmentdepartmentstoKaoshiproductionsafetysupervisionresponsibilities,doagoodjobintheindustryinthisfieldinvestigationandsecurityrisks,havetocarryoutremediationtoensuresafetyinproduction.Inviewoftheexistingproblems,conscientiouslydoagoodjobofinspectionworkintheindustry,doin-depthinspectionlinetoreally,inspectionoflawenforcementshouldbestrict,styleofworktohard,rectificationmeasurestobeimplemented.Theindustrydepartmentinchargeoftheperformanceoftheirdutiesandmajorsafetyhazardsinvestigationremediationtoconductsupervisionandinspection,ofworkarenoteffective,thedutynottoimplement,throughinterviews,bulletin,accountabilityandothermeasures,ZadokPromotingtheimplementationoftherectification.Thecountyandtheparkmanagementcommitteetoearnestlyimplementtheterritorialsupervisionresponsibility,beartheoverallresponsibilityforproductionsafetyworkintheregion,tofurtherclarifythegovernmentleadershipandtheleadershipofvariousdepartmentsofproductionsafetyworkresponsibility,judgedtheregional15'