地铁控制区内深基坑工程支护与降水设计研究

Research on Support and Dewatering Design for Deep Foundation Pit Engineering in Subway Control Area

文章以厦市美峰花园安置房二期项目基坑工程为研究对象,结合基坑周边环境和地质情况,对基坑支护采取分段设计的方法,计算基坑的内力和稳定性,并对其降水量和降水井数量进行设计分析。结果表明,基坑采用排桩结合锚索、排桩悬臂,局部采用排桩结合内支撑、双排桩及自然放坡等联合支护方案,基坑内力和稳定性系数均满足设计要求;按潜水完整井计算得到基坑的日最大涌水量为410m^(3)/d,共设计27口管井进行降水,可以达到降水水位为基坑底以下0.5m的要求。

This paper takes the foundation pit engineering of the second phase of Meifeng Garden resettlement house project in Xiamen as the research object.Combined with the surrounding environment and geological conditions of the foundation pit,a segmented design method is adopted for the foundation pit support,the internal force and stability of the foundation pit are calculated,and the dewatering volume and number of dewatering wells are designed and analyzed.The results show that when the foundation pit adopts the combination of row piles with anchor cables,row pile cantilevers,and the local part adopts the combination of row piles with internal support,double row piles and natural slope and other combined support scheme,the internal force and stability coefficient of the foundation pit both meet the design requirements.The daily maximum water inflow of the foundation pit is 410 m^(3)/d calculated according to the completely penetrating well in phreatic water.A total of 27 pipe wells are designed for dewatering,which can meet the requirement that the water level is 0.5 m below the bottom of the foundation pit.