北京地区建筑抗浮设防水位的合理确定与单建地下车库基础形式选择

Reasonable Determination of Groundwater Level for Subsurface Structure Buoyancy Resistance and Choice of Foundation Type for Solely Underground Garage in Beijing Region

北京地区地下水位的影响因素包括大气降水、地质、水文条件和人为因素。科学地预测构筑物使用寿命期间可能出现的最高地下水位,并以之为边界条件进行渗流计算,是确定地下结构抗浮设防水位的科学方法。对于单建地下车库,地下水位较高时,宜选用抗力平衡型抗浮措施,并采用片筏基础或箱形基础;反之宜选用浮力消除型抗浮措施,并最好采用独立柱基础。工程实践证明了方法的有效性和经济性。

The influence factors of groundwater level include rainfalls, soil and hydrogeology conditions and human activity. The steps of scientific determination method of groundwater level for subsurface structure buoyancy resistance are as follows： firstly, forecast the highest groundwater level in the service period of the subsurface structure; then analyze the seepage of stratums with the boundary condition of the highest groundwater level. For the sole underground garage, when the groundwater level is relatively high, the buoyancy resistance measure based on resistance balance and raft or box foundations is suggested; whereas the buoyancy resistance measure based on eliminating buoyancy and the separate foundation under column is suggested. The engineering practice indicated the availability and economy of the method.