加筋大直径搅拌桩重力式挡土墙技术在深基坑工程中的应用

Application of Gravity Retaining Wall Technology of Reinforced Large Diameter Stirred Pile in Deep Foundation Pit Engineering

为提升软土地区深基坑工程的工程质量,文中以某高层建筑项目为例,设计加筋大直径搅拌桩重力式挡土墙支护方案及对该方案的施工技术进行分析,并对工后的施工效果进行评价。结果表明,施工后的桩底标高为150mm,桩位偏差为15mm,桩的垂直度偏差为0.5%;桩身完整均匀,桩身混凝土强度达到1.2MPa;基坑围护结构最大变形位移值为20mm。所有的检测值未超过预警值,满足设计方案的要求。加筋大直径搅拌桩重力式挡土墙技术的工程总造价为8210.4万元,比钻孔灌注桩高了3.6%;施工周期为60d,比钻孔灌注桩的施工周期缩短了50%。加筋大直径搅拌桩重力式挡土墙技术具有优良的社会经济效益。

In order to improve the quality of deep foundation pit engineering in soft soil area,this paper takes a high-rise building project as an example to design the reinforced large-diameter stirred pile gravity retaining wall support scheme and analyze the construction technology of the scheme,and evaluate the construction effect after construction.The results show that the elevation of pile bottom is 150 mm,the deviation of pile position is 15 mm,and the deviation of pile perpendicality is 0.5%.The pile body is complete and uniform,and the concrete strength of the pile body reaches 1.2 MPa;The maximum deformation displacement value of foundation pit retaining structure is 20 mm.All the test val-ues do not exceed the warning value and meet the requirements of the design scheme.The total engineering cost of gravity retaining wall tech-nology of reinforced large-diameter stirred pile is 82.104 million yuan,which is 3.6%higher than that of bored pile.The construction period is 60 d,which is 50%shorter than that of bored pile.The technology of reinforced large-diameter stirred pile gravity retaining wall has excel-lent social and economic benefits.