井点降水法在复合地层基坑工程中的应用研究

Application Study on Well Point Dewatering for Foundation Pit with Composite Strata

井点降水法作为一种成熟的基坑降水施工方法,被广泛应用在地铁车站基坑施工.依托深圳地铁车站基坑工程,介绍了井点降水在软土-砂层复合地层基坑工程中应用时遇到淤泥质软土降水难度较大、富水砂层存在地层变形以及周边基坑施工影响等问题.通过利用加密真空井点降水以及对基坑降水过程中地下水位、地层变形和基坑稳定性进行严密监测等方法,有效解决了降水过程中存在的问题,为将来在相似施工条件下井点降水法的应用提供借鉴.

Well point dewatering is a mature method which is widely used in foundation pit construction. Based on the subway station construction in Shenzhen metro line, the difficulties are introduced during dewatering in geological conditions of mucky soft soil and sandy soil with rich groundwater, including low efficiency of dewatering in mucky soil, large deformation of sandy stratum and serious disturbance for surrounding construction. After adopting the methods, such as vacuum well dewatering and rigorous monitoring of groundwater level, formation deformation and the stability of foundation pit during dewatering, the unfavourable effects are mitigated and diminished. The experiences could provide a great significance for further construction.