（1）深井布置
区间明挖段基坑基底长186.25m，基坑基底宽31～35.6m，开挖深度：9.61m～17.85m，拟在此明挖段布置两排深井井点，一排在基坑中线上，一排在基坑南侧边坡外侧，井点间距30m，共布设15个。
井深采用下式计算： H≥H1+△h+iL+l
式中：H---井点管埋置深度（m）
H1---井点埋设面与基坑底的距离（取13m）
△h---降水后地下水位至基坑底的安全距离（取 0.5m） i--- 降水曲线坡度（取0.1）
L---井点管中心至基坑侧边的距离（取18m） l---滤水管长度（取2m）
经计算：井管埋深为17.3m。钻孔深定为17.3m。 （2）深井埋设及洗井
深井采用旋转钻机成孔泥浆护壁，成孔直径为800mm。
深井井管沉放前先进行清孔，清孔采用吊筒反复上下提升洗孔。井管安放必须垂直，井管与孔壁间用粒径3-15mm砾石填充作过滤层，井口下0.5m内用粘土填充夯实，并设井盖防护。安放水泵前，再进行一次清洗滤井，冲除沉渣，保持滤网畅通。 潜水电泵用绳吊入滤水层部位，潜水电机、电缆及接头要有可靠的绝缘，并配置保护开关控制。
3、深井井点施工顺序
井位放样→做井口、安护筒→钻机就位、钻孔→回填井底→豆石垫层→吊放井管→回填管壁与孔壁间过滤层→安装水泵及控制电路→试抽→降水井正常工作
4、井点监测
沿基坑四周布设φ86mm的降水观测孔，利用电测水位仪、自测水位仪进行水位量测。其要求包括：
（1）降水开始前，所有抽水井、观测井统一联测静止水位。并统一编号、统一基准点。
（2）选择有典型代表性的一排观测孔，从降水开始，按抽水试验观测要求进行水位观测。
（3）根据水位变化情况与预测计算分析，及时发出问题，调整抽排水系统，并通过与基坑其它岩土工程监测资料进行对比分析，及时建议、确定应采取的防治措施。
5、排水设施
从深井中抽出的水，沿基坑四周排水沟汇集到沉淀池中，经沉淀后排入市政排水管道。开挖到基坑底后，基坑底四周设水沟和集水井，汇集边坡和基底的渗水，并用潜水泵抽到基坑四周的排水沟，经沉淀排入市政排水管道。
标书制作系统
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We will continue to improve the company's internal control system, and steady improvement in ability to manage and control, optimize business processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of evaluation complying with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full communication \o constantly perfect ERP, and BFS++, and PI, and MIS, and SCM, information system based construction, full integration information system, achieved information resources shared; to expand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to perfect daily run maintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS++, and ERP, and SCM, technology application oftraining, improve employees application information system of capacity and level. Humanistic care to ensure \To strengthening Humanities care, continues to foster company wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helped trapped, care difficult employees; carried out style activities, rich employes life; strengthening health and labour protection, organization career health medical, control career against; continues to implementation psychological warning prevention system, training employees health of character, and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. o strengthen risk management, ensure that the business of \ngthened business plans management, will business business plans cover to all level, ensure the business can control in control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to implementation State-owned assets method, further specification business financial management; to perfect risk tube control system, achieved risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize trading, and strive to achieve \ding to law, standardize and fair.\of performance management, to ensure that potential employees \strengthen performance management, process control, enhance employee evaluation and levels of effective communication to improve performance management. To further quantify and refine employee standards ... Work, full play party, and branch, and members in \se\of core role, and fighting fortress role and pioneer model role; to continues to strengthening \p construction, full play levels cadres in enterprise development in the6、降水施工技术保证措施
（1）降水施工方案必须上报监理审批后方可实施，降水应指定专人负责抽水、观测，做好观测记录，及时反馈信息。
（2）井管施工过程应严格控制成井口径、井深、井管配制、砂石料填筑、洗井试抽五道工序质量。
（3）按降水监测要求做好监测记录，根据水位、水量变化情况及时采取调整措施。 （4）井管使用时，应对称同时抽水，使水位差控制在要求限度内。
（5）井点供电系统应采用双线路，防止中途停电或发生其他故障，影响排水。 7、为防止降水对周围环境产生不良影响的施工措施
在工程降水过程中，应采取如下措施，防止对邻近周围环境的影响： (1)加强对周边地表及建筑物的沉降观测，以及时取得数据，保证安全施工。 （2）一旦发生水位观测孔中的水位、水量变化异常，局部区域出现超降现象，则应马上采取措施，停止降水。必要时进行地下水回灌，回灌采用机械加压灌注法。
7.1.3土方开挖 本标段区间隧道明挖段土方约8.5万方，土质自上而下为素填土，砂质粘性土、砾砂（靠近暗挖段有一尖灭带）及砾质粘性土，基坑开挖深度9.61～14.705m，采用分层开挖。
1、开挖准备工作
（1）按设计规定的技术标准，地质资料以及周围建筑物和地上、地下管线的详细资料，严格细致的作好深基坑施工组织设计（包括周围环境的监控措施）和施工操作规程，对开挖中可能遇到的漏水及边坡失稳现象制定相应的应急措施。
（2）准备好出土、运输和弃土机具，保证基坑开挖中连续有效的出土，加速开挖支撑的速度，减少地层的移动。
（3）将边坡支护及锚索安装的机械设备和材料备齐，以利于边开挖边支护，减少边坡的暴露时间，利于周围土体稳定，保证施工正常进行。
（4）对基坑、人工挖孔桩、周围环境及管线编制详细的监控方案，并预先作好监测点的布设，初始数据的测试及监测仪器的调试工作，使监测工作准备就绪。 （5）基坑四周设排水沟，保证场地外地表水不流入基坑。基坑内设集水沟、深井井点，将地下渗水、从深井中抽出的水顺利排到场外沉淀池。
（6）开始深井井点降水，使水位降到开挖面以下。 2、土方开挖
开挖设备采用挖掘机配自卸式汽车。为了保证区间隧道从明暗挖分界处尽早进洞施工，将施工便道位置设在距明暗挖分界处30m的CK13+407位置。施工便道坡度18%，碎石路面宽6m，为配合分层开挖的需要，便道随挖土层高分三次逐渐降坡至基坑底。 本明挖段施工通道以西的30m分四层进行开挖，施工通道以东分三层进行开挖。开挖分层布置见下图。
（1）先开挖第一层锚索标高以上部分。第一层以此标高由施工便道位置向东西两
f backbone backbone role; to full strengthening members youth work, full play youth employees in company development in the of force role; to improve independent Commission against corruption work level, strengthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further strengthen publicity and education, improve the overall legal system. We must strengthen safety management, establish and improve the education, supervision, and evaluation as one of the traffic safety management mechanism. o conscientiously sum up the Olympic security controls, promoting integrated management to a higher level, higher standards, a higher level of development. Employees, today is lunar calendar on December 24, the ox Bell is about to ring, at this time of year, we clearly feel the pulse of the XX power generation company to flourish, to more clearly hear XX power generation companies mature and symmetry breathing. Recalling pastone another across a railing, we are enthusiastic and full of confidence. Future development
opportunities, we more exciting fight more spirited. Employees, let us together across 2013 full of challenges and opportunities, to create a green, low-cost operation, full of humane care of a world-class power generation company and work hard! The occasion of the Spring Festival, my sincere wish that you and the families of the staff in the new year, good health, happy, happy10
侧开挖，开挖1.5m即修平边坡进行土钉支护。挖至本层底安装腰梁，施工预应力锚索。 （2）第二层由基坑东西两侧向施工便道挖掘，深度达到第二排锚索标高处，由于施工便道以西土方少，速度相对较快，可在施工便道向西的10m范围内降坡至开挖面，保证此段有20m长的基坑进行框架结构施工。本层施工方法同第一层，并要施作第二排预应力锚索和腰梁。
（3）第三层，亦从东西两端向施工便道施工，便道以东段挖到基坑底，便道以西段下挖3m。本层将挖至出入段线的基底，施工时控制好标高，避免超挖，继续向下挖掘区间隧道基底时，采取措施减少对出入段线基底的扰动和超挖。
（4）施工便道以西的区间隧道埋深较大（约6m），故此段增加一开挖层，在第四层时才开挖到区间隧道基底。
（5）在便道位置将出入段线的基底挖至与区间隧道基底相同的高度，以利于右线土方和结构施工，并为右线暗挖段出碴运料提供便道。
3、开挖措施
（1）在基坑开挖施工时和完工后，均要在基坑四周施作排水沟和集水井，集水井每80m布设一个，以便及时将基坑积水排走。
（2）避免出入段线基底扰动的措施
CK13+350～CK13+435段区间隧道结构底与出入段线结构底标高相关较大，开挖右线区间隧道基底时，将破坏出入段线结构基础。为减少区间隧道结构施工对出入段线基底下土体的扰动，避免因回填不密实造成的出入段线结构不均匀沉降，保证出入段线结构的安全，建议在区间隧道右线左侧插打钢板桩，然后挖基施工。
钢板桩一次性投资较大，但可以拔出重复使用，故费用较省。
1）、支护设计：根据两结构的位置关系，在CK13+350～CK13+435插打钢板桩。钢板桩插打深度进入区间隧道结构底3m。上部比区间隧道结构顶面高出１m，故钢板桩长度由5.68m渐变到10.13m，拟采用拉森Ⅲ型钢板桩。
钢板桩悬壁长度在2.5m以内可不加横撑，悬壁长度大于2.5m时，要在区间隧道顶面以上架设横撑，撑于人工挖孔桩上，悬臂长小于4m时加一道横撑，大于4m加2道横撑，以确保钢板桩稳定。第二层支撑在完成结构底板施工后，边施工侧墙、顶板边拆除。 ①当基坑开挖到出入段线结构底标高时，由技术人员放出区间隧道结构边线，外放1.0m作为打入钢板桩的中心位置，把20吨吊车及450吨激振力的振锤放入基坑内的相应位置。
②钢板桩于打入前将桩尖处的凹槽底口封闭，避免泥土挤入，锁口处涂以黄油。检查是否有锁口变形、桩身弯曲的现象，如果有，要进行校正或更换。
③为了保证钢板桩垂直打入和打入后钢板桩墙面平直，在钢板桩的打入位置处安装围檩支架，其型式为双面双层桁架式。
第一层围檩的安装高度为工作面上0.5m，双面之间的净距为310mm（比两块钢板桩组合宽度大10mm），围檩支架用工字钢制作。
④钢板桩打入
先用吊车将第一根钢板桩吊至插桩点就位，随即套上桩帽，用振锤打入，在打入过程中，应在相互垂直的方向上用两台经纬仪加以控制，随时纠偏。
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We will continue to improve the company's internal control system, and steady improvement in ability to manage and control, optimize business processes, to ensure smooth processes, responsibilities in place; to further strengthen internal controls, play a control post independent oversight role of evaluation complying with third-party responsibility; to actively make use of internal audit tools detect potential management, streamline, standardize related transactions, strengthening operations in accordance with law. Deepening the information management to ensure full communication \o constantly perfect ERP, and BFS++, and PI, and MIS, and SCM, information system based construction, full integration information system, achieved information resources shared; to expand Portal system application of breadth and depth, play information system on enterprise of Assistant role; to perfect daily run maintenance operation of records, promote problem reasons analysis and system handover; to strengthening BFS++, and ERP, and SCM, technology application oftraining, improve employees application information system of capacity and level. Humanistic care to ensure \To strengthening Humanities care, continues to foster company wind clear, and gas are, and heart Shun of culture atmosphere; strengthening love helped trapped, care difficult employees; carried out style activities, rich employes life; strengthening health and labour protection, organization career health medical, control career against; continues to implementation psychological warning prevention system, training employees health of character, and stable of mood and enterprising of attitude, created friendly fraternity of Humanities environment. o strengthen risk management, ensure that the business of \ngthened business plans management, will business business plans cover to all level, ensure the business can control in control; to close concern financial, and coal electric linkage, and energy-saving scheduling, national policy trends, strengthening track, active should; to implementation State-owned assets method, further specification business financial management; to perfect risk tube control system, achieved risk recognition, and measure, and assessment, and report, and control feedback of closed ring management, improve risk prevention capacity. To further standardize trading, and strive to achieve \ding to law, standardize and fair.\of performance management, to ensure that potential employees \strengthen performance management, process control, enhance employee evaluation and levels of effective communication to improve performance management. To further quantify and refine employee standards ... Work, full play party, and branch, and members in \se\of core role, and fighting fortress role and pioneer model role; to continues to strengthening \p construction, full play levels cadres in enterprise development in the第一根桩打完后，分别在第一根桩两侧各打入三根钢板桩，位置和垂直度检查无误后，可在一侧依次打入其他的钢板桩。
在离合拢还有八块板桩时，停止插打，测出合扰段距离，然后边打边修正，以使钢板桩能顺利合扰。如果出现偏差，可采用异形钢板桩合扰。
钢板桩合拢以后，在侧墙以上部位的钢板桩上焊制牛腿，安放围檩，用φ275钢管做为支撑焊接在围檩处（无需施加预应力）。其钢管间距2.0m。
⑤支撑边开挖边架设。
⑥在右线结构及防水层保护层施工完成后回填土并夯实，才能拔出钢板桩，拔桩时注意减少对土体扰动。
2）、注意事项及技术要求
①钢板桩应放线施工，桩头就位必须正确、垂直，沉桩过程中，应随时检测，发现问题，及时处理。
②插打前应在锁口内涂以黄油、锯末等混合物，以防漏水。
③在插打钢板桩时，如起重设备高度不够，允许改变吊点位置，但该点位置不得低于桩顶以下1/3桩的长度。
④打入过程中必须随进检查，如发现问题及时处理。 ⑤加强监测确保钢板桩稳定。
7.1.4 结构施工 区间明挖段结构形式为矩形框架结构，分单跨、双跨断面。其组合形式是从区间隧道和出入段线共用的双跨断面，过渡为各自的单跨断面，最终出入段线左右线又合并为双跨断面，从线路纵坡看出入段线和区间隧道也由同一标高过渡为不同标高，结构变化较为复杂。
（一）主体结构施工安排
根据结构相对位置，按以下原则安排施工： 1、出入段线与区间隧道在同一标高的同时施工。
2、区间隧道与出入段线不在同一标高的先施工标高较低的区间隧道，在防水层施工完成后回填夯实至出入段线标高后再进行出入段线结构施工。
3、出入段线由单跨结构合并为双跨结构的三角地带，先施作两结构中间防水层，再同时施作两单跨结构。
（二）主体结构施工分段
具体分段及施工顺序见区间明挖段结构分段施工示意图。 （三）施工前的准备工作
1、基坑开挖到设计标高，仔细进行测量，放样及验收，严禁超挖。 2、掌握框架结构浇筑和支撑拆除的要求及操作程序，对侧墙、顶板
模型支撑系统进行设计、检算，报监理业主审批准后根据施工进度提前安排备料。
3、对内部结构施工顺序，施工进度安排，施工方法及技术要求向工班及全体管理
f backbone backbone role; to full strengthening members youth work, full play youth employees in company development in the of force role; to improve independent Commission against corruption work level, strengthening on enterprise business key link of effectiveness monitored. , And maintain stability. To further strengthen publicity and education, improve the overall legal system. We must strengthen safety management, establish and improve the education, supervision, and evaluation as one of the traffic safety management mechanism. o conscientiously sum up the Olympic security controls, promoting integrated management to a higher level, higher standards, a higher level of development. Employees, today is lunar calendar on December 24, the ox Bell is about to ring, at this time of year, we clearly feel the pulse of the XX power generation company to flourish, to more clearly hear XX power generation companies mature and symmetry breathing. Recalling pastone another across a railing, we are enthusiastic and full of confidence. Future development
opportunities, we more exciting fight more spirited. Employees, let us together across 2013 full of challenges and opportunities, to create a green, low-cost operation, full of humane care of a world-class power generation company and work hard! The occasion of the Spring Festival, my sincere wish that you and the families of the staff in the new year, good health, happy, happy12
人员进行认真交底，做到人人心中有数。
4、垫层浇筑前，要针对基底情况进行基底处理，并施作接地网。 （四）施工顺序及工艺流程 主体结构按以下四个阶段顺序作业： 1、接地网垫层底板防水层。 2、底板。 3、侧墙、顶板。 4、侧墙、顶板防水层。 结构施工顺序图如下：
80mm厚C15细石混凝土保护层2mm厚双组份聚氨酯涂料C30S8钢筋混凝土顶板Ⅳ侧墙顶板防水层Ⅲ:结构侧墙顶板2mm厚无焦油双组份聚氨酯涂料 纺布 无 m / g 0 5 3 C30S8钢筋混凝土侧墙240砖墙Ⅱ结构底板Ⅰ垫层、底板防水层双跨结构施工顺序图
（五）主要施工方法 1、基底检查及处理
（1）检查基底地质情况、土质与承载力是否与设计相符，如承载力不足可采用基
底换填等措施。
（2）基底超挖在30cm以内时，可用原状土回填压实，密实度不得低于原状土，或用与垫层与垫层同级砼回填，或用砾石、砂、碎石回填压实，压实机械采用蛙式打夯机。
2、接地网施工
明挖段基坑开挖后，按施工设计要求进行钻孔、挖沟、埋设铜管钢排及引出线，作好回填，并按要求安置盒罩保护引出线。完工后及时量测接地电阻、接触电位差及跨涉电位差，并按有关要求进行不合格时的处理。
区间暗挖段亦按上述内容施作接地网。
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