软黏土地区某深大基坑开挖变形分析

ANALYSIS OF EXCAVATION DEFORMATION OF A DEEP AND LARGE FOUNDATION PIT IN SOFT CLAY AREA

文中结合杭州某深大基坑工程,介绍了该工程所在场地土层条件及基坑支护形式及基于开挖全过程中的实测数据,系统地分析了围护结构的变形、土体水平位移、建筑物沉降及路面裂缝的变化规律。研究发现深层土体的开挖比浅层土的开挖能产生更大的应力,使得基坑产生更显著的变形。随基坑开挖深度的增加,围护结构挠曲变形加速增大。围护结构及土体的变形主要发生在开挖阶段,随底板的浇筑,变形逐渐趋于稳定。研究成果可为同类工程提供一定参考。

Firstly,the soil condition and the supporting form of a deep and large foundation pit in Hangzhou are introduced.Then,the deformation law of enclosure structure,horizontal displacement of soil,building settlement and pavement cracks were systematically analyzed based on the measured data during the whole excavation process.The study found that the soils excavated in deep could produce greater stress than the soils excavated in shallow,resulting in more significant deformation of the foundation pit.As the excavation depth of the foundation pit increases,the horizontal displacement of the envelope structure increases rapidly.Moreover,the deformation of the envelope and the soil mainly occurs during the excavation stage,and the deformation gradually stabilizes with the pouring of the bottom plate.The research results may provide the guidance for similar projects.