抽渗结合法在北京地区基坑降水施工中的应用

APPLICATION OF INTEGRATED PUMPING AND SEEPING METHOD IN DEWATERING OF FOUNDATION EXCAVATION IN BEIJING

北京地区的基坑降水一般大多采用管井抽水的方法,由于在抽水过程中会将土层中的细颗粒带出,容易引起周边建筑物、道路、地下管线的不均匀沉降,另外,大量抽取地下水对北京地区的地下水资源也是一个非常大的浪费。采用抽渗结合法进行基坑降水,利用水力坡度的原理,将上层的滞水和潜水引到深层渗透系数较大的砂卵石层中,既可避免长时间抽水不断地将土层中大量的细颗粒带出,也可避免地下水资源被大量的浪费。

Pumping tubular well commonly used in dewatering of deep excavations in Beijing often leads to unequal settlement of surrounding buildings, roads and underground pipelines because the fine granule of soil is taken out when pumping, which leads to waste of the groundwater resource in Beijing. By use of hydraulic gradient principle, integrated pumping and seeping method is to make upper sluggish water and underground water get to sand cobble layer whose permeability coefficient is bigger to avoid the come out of fine granule of soil during pumping and the waste of groundwater resource.