暗浜软土地区大规模深基坑支护施工方案设计

Design of Large Scale Deep Foundation Pit Support Construction Scheme in Soft Soil Area

文中结合某大型深基坑工程实践,对暗浜软土地区的深基坑支护方案设计、土方开挖设计及降水设计进行了分析,并对基坑的施工效果进行监测。结果表明,该工程采用的支护结构方案为放坡+重力坝、放坡+工法桩+钢支撑,周边地面累计沉降量为22.4 mm,周边管线累计沉降量为12.3 mm,支护结构顶部累计竖向位移为27.5 mm,支护结构顶部累计水平位移为30.4 mm及支撑轴力水平力为2500 kN,所有监测点处的基坑周边沉降及支护结构变形量均未超过预警值,证明本工程采用的支护结构方案及施工技术安全可靠。

Combined with the construction practice of a large deep foundation pit project,the paper analyzes the design of deep foundation pit support scheme,earthwork excavation design and dewatering design in the soft land area of the dark creek,and monitors the construction effect of the foundation pit.The results show that the supporting structure scheme adopted in this deep foundation pit project is slope release+gravity dam,slope release+construction pile+steel support.The cumulative settlement of the surrounding ground is 22.4 mm,the cumulative settlement of the surrounding pipeline is 12.3 mm,the cumulative vertical displacement of the top of the supporting structure is 27.5 mm,the cumulative horizontal displacement of the top of the supporting structure is 30.4 mm and the horizontal force of the supporting axial force is 2500 kN.The surrounding settlement of the foundation pit and the deformation of the supporting structure at all monitoring points do not exceed the warning value.It is proved that the support structure scheme and construction technology adopted in this project have obvious safety and reliability.