一、滤水层与土井组合降水法的由来上海地区的地下建筑,例如人防工事、箱形基础等,由于地下水位高(一般离地表0.7米)、埋深较浅、及地下管线比较复杂等原因,一般情况下,采用明挖法来构筑。设计时,根据使用的要求,开挖深度常为 First, the combination of the drainage layer and soil wells The origin of the precipitation method in Shanghai, such as civil defense construction, box foundation, etc., due to high groundwater level (generally 0.7 meters from the surface), shallow depth of burial, and relatively complex underground pipelines, etc. The reason, under normal circumstances, is to use open cut method to build. When designing, the depth of excavation is often