软土地区深大基坑工程施工监测分析技术研究

软土地区深大基坑施工对周边环境的影响机理十分复杂。以软土地区深大基坑工程为背景，采用现场监测的方法，探索了软土地区深大基坑工程施工对基坑周围环境的扰动影响，研究了深大基坑开挖过程中基坑的变形、支撑轴力以及基坑周围孔隙水压力随开挖的变化规律。研究表明：由于基坑开挖引起的应力释放，使基坑底部土体隆起，诱发基坑周围土体向基坑方向松动；地表竖向位移叠加效果随着开挖深度的增加而减小，最大竖向位移的位置在两基坑的中间处，随着施工的持续，其对地下连续墙的影响基本消失；孔隙水压力随时间增长急剧减小，此后一直保持稳定。研究成果可为今后此类施工提供理论依据和前期指导。

Research on Construction Monitoring Analysis Technology of Deep and Large Foundation Pit in Soft Soil Area

The influence mechanism of deep and large foundation pit construction in soft soil area is very complex. This paper uses on-site monitoring method to explore the disturbance of deep foundation pit construction in soft soil area on the foundation pit surrounding environment, and studies the variation law with the excavation of the deformation and supporting axial force of the foundation pit, as well as the pore water pressure around the foundation pit during the excavation process of deep and large foundation pit. The research shows that the stress release from the excavation leads to the uplifting of the soil at the bottom of the foundation pit and the loosening of the soil around the foundation pit to the direction of the foundation pit. The vertical surface displacement superposition effect decreases with the increase of excavation depth, and the maximum vertical displacement of the position appears at the middle of two pits. Along with the continuous construction, the impact on the underground continuous wall gradually disappears. The pore water pressure decreases sharply with the increase of time, and keeps stable later. The research results can provide theoretical basis and early guidance for future construction.