1、一、 概述General 90万吨/年乙烯装置地下管道污染雨水及生产污水管道（SD）部分主管线施工时，由于沟深较深，且靠近装置区已经施工完毕的道路，故管沟开挖时无法进行放坡处理，为防止开挖时发生塌陷，将已经施工完毕的路基破坏掉，因此靠近路边的沟槽边坡在施工时需要进行特殊施工技术处理，经慎重考虑，采用打钢板桩的方式来保护路基。需要进行技术处理的道路有2#路（MHS.PC-08MHS.PC- 11之间）、4#路、8#路（MHS.PC-49MHS.PC- 51之间）、10#路。During the main pipeline construction of pollution rain water 2、and production pollution pipe (SD) in UG pipe of 900 KTAY ethylene plant ,we will implement the special construction technical treatment to the trench bank preventing collapse and damage to the completed road base instead of sloping treatment which could not be executed as proposed before because of3、 the trenchs depth and the completion of the road adjacent to the plant. With carefully consideration ,we take the method of driving steel plate pile to protect the road base and this method will be used upon NO.2 Road (between MHS.PC-08 & MHS.PC- 11),NO.4 Road ,NO.8 Road (between MHS.PC-49 & MHS.PC4、-51) and NO.10 Road.二、钢板桩施工 steel plate construction 2.1、开挖前，首先进行管沟开挖放线。Setting out before trench excavation. 2.2、管沟开挖应提前进行井点降水，确保施工阶段沟槽无地下水。Well point dewatering before trench excavation to ensure there remains no UG water during the whole period of construction.2.3、沟槽最深挖掘深度为4.6米，因此采用拉森钢板桩，规格为12米/根5、。The max depth of the trench excavated is 4.6m and we use the LASEN steel plate pile which length is 12 meter。2.4、钢板桩的位置距离管带基础600mm。钢板桩位于道路一侧，采用单侧钢板桩铺设方法。沟槽另一侧进行放坡，坡度不小于1：1。The distance between the steel and the pipeline foundation is 600mm. Drive steel plate pile on one side of the trench and slope6、 on the other side with the grade no less than 1:1.2.5、钢板桩采用重锤锤击或夯机锤击的方式进行。钢板桩顶部应高出地平面200mm。Drive the pile by means of punching with heavy punch or punning with punier and the top of the pile should be 200mm higher than the terrace.2.6、钢板桩必须垂直，严禁钢板桩向沟槽方向倾斜。The steel plate pile must be vertical and l7、ean towards the trench is forbidden.2.7、相临的两块钢板桩必须相互正反紧密咬合。The steel plate piles adjacent to each other must tightening bite forward reverse.2.8、由于需要打钢板桩的距离很长，因此为节约施工成本，采取分段打桩的方式进行。每段大约在50米，共需要钢板桩220根，总重70吨。桩机立在需要开挖的沟槽上，沿着沟槽的方向边打边退，桩机下面铺设钢板，钢板规格为40002000，=20mm，共计5块。We drive the piles by means of sub8、section to reduce the construction cost caused by the long piling distance with each subsection 50m in length and totally 220 steel plate piles in number and 70t in weight .The driving machine stands where the trench should be excavated and retrogrades along the trench with 5 steel plates sized 40009、2000,=20mm under its body. 2.9、当一段钢板桩打完后，立即进行土方开挖。将开挖出的泥土堆放到沟槽的另一侧。无法进行堆放的泥土需要用运输车运到甲方指定的渣土场（距离施工现场9公里）进行堆放。Excavate immediately after construction for one subsection is finished and pile the earth excavated out on the other side of the trench ,the remained earth which couldnt be piled should be tra10、nsported to the slag lot(9 km away from the construction site) designated by the client for piling. 3.0、当管道安装完毕试压合格后，经共检合格，马上进行沟槽回填。回填土需要进行压实，回填完毕后，方可将钢板桩拔除。拔除钢板桩同样采用震动起重机，起重机站在道路上，同时需要对已经铺设完毕的路面进行保护，在路面上铺设=20mm的钢板，钢板规格为40002000，共计5块。Backfill the trench after the pipe erection is finished and qualif11、ied in pressure test as well as the test by all the authorities. the backfilling earth should be compacted and only the backfilling is finished could the steel plate be dismantled by vibration crane standing on the terrace with 5 steel plate sized =20mm ,40002000 under its body to protect the n comp12、leted road.3.1、当此段沟槽施工完毕后，方可进行下段沟槽施工。沟槽的开挖断面图见详图1：Only after this section trench is completed could the next trench be constructed ,and the section of excavated trench see detail 1:四、质量控制：Quality Control41基坑开挖的日常质量监督工作由项目部工程部具体负责，设专职质量检查员负责日常质量监督和检验工作。Quality department of project dept. is responsib13、le for daily quality supervision for base trench excavation. Full time quality inspector shall be designated and responsible for daily quality supervision and inspection.42严格工序交接制度，未经检查或经检查上道工序不合格，严禁进行下道工序施工。Execute work procedure handover system strictly; forbid to execute next work procedure strictly if the work is not inspected or the work procedure is unqualified after inspection.五、安全控制：Safety Control51施工人员必须穿戴好防护用品。依据JHA对施工班组进行安全交底，强化安全意识。The worker should wear PPE correctly. Make safety clarification to workers according to JHA to enhance their safety consciousness.