天津市某医院深基坑工程变形特性及预测研究

Deformation of Deep Foundation Pit of a Hospital Construction Project in Tianjin and the Prediction

依托天津地区软土大背景下的深基坑工程,对天津市某医院大尺度深基坑开挖施工过程中的现场观测数据进行理论分析,并利用FLAC3D软件建立3D基坑模型并对基坑开挖支护全过程进行动态模拟,将软件计算结果与基坑现场监测数据进行对比。对比结果表明:模拟所得数值与现场观测数据规律较为贴切,随着基坑开挖进一步进行,外侧土体位移量逐步增加,当基坑开挖全部完成时,土体出现最大沉降量,桩顶水平位移与深层水平位移均满足监控测量标准的要求,说明所选取的支护结构等措施可以较好地控制基坑围护结构的变形并提出预测最大侧向位移的公式为后续类似工程提供一定的参考依据。

A case study was carried out for a large-scale excavation of deep foundation pit under soft soil background of a hospital construction project in Tianjin City. Field observation data during the excavation was analyzed theoretically, and a 3 D model was established using FLAC3 D software. Dynamic simulation and support process were performed. Software calculation results were compared with on-site monitoring data. Results show that the simulated values well agreed with the on-site observation data. With the ongoing excavation, displacement of the lateral soil gradually increased. Upon the pit excavation completion, the settlement reached the maximum. Both horizontal displacement and deep horizontal displacement could meet the requirements of monitoring and measurement standards, indicating that the support structure and other measures selected in this project could better control the deformation of the retaining structure. A formula for predicting the maximum lateral displacement was proposed for similar projects as a referential base for similar cases.