降水治理软土深基坑周围的建筑物差异沉降

CONTROLLING DIFFERENTIAL SETTLEMENT OF BUILDING AROUND DEEP EXCAVATION IN SOFT CLAY BY DEWATERING

软土深基坑周围的已建建筑物在基坑开挖过程中，极易产生差异沉降。如何从众多处理技术中选择一种较为经济合理的方法来处理差异沉降，必须根据当时当地的具体情形加以比较，采用最经济可行的治理方法。本文以上海地铁２号线一车站深基坑周边的一栋居民楼为工程背景，在上海软土地区的低渗透性淤泥质粘土中，首次探索性地采用了井点降水的方法治理建筑物的差异沉降，控制建筑物的倾斜度。证明了利用井点降水来治理软土地基上建筑物差异沉降以及降水纠偏的方法是可行的。

Soft clay has four distinct properties: high compressibility, high water content, high sensentivity and low strength. The deep excavation in soft clay is most prone to result in big differential settlement of the existing building and even causes serious damage to the building. The protection of a six - storeyed building adiacent to a excavation is presented in this paper, in which the design and execution of a differential settlement controlling plan are recorded in detail. This is the first time of using well dewatering to treat differential settlement in Shanghai low permeability muddy soil and the result is quite successful.