敏感环境下深基坑的设计与三维数值分析

Design and 3D Numerical Analysis of a Deep Excavation in Close Proximity to Sensitive Properties

研究目的:基坑工程开挖深度和规模越来越大,以及周边越来越复杂敏感的环境条件,给基坑工程的设计施工提出了更严格的变形控制要求,因此对基坑及周边环境变形的预测非常重要。研究结论:详细阐述了上海软土地区一邻近多幢6层砖混结构住宅的深基坑工程支护设计方案及周边环境保护的技术措施。通过PLAXIS 3D Foundation软件建立三维有限元模型模拟了基坑开挖对邻近住宅的影响,与实测数据的对比表明,围护体变形和邻近住宅的沉降计算值与实测值较吻合,建立的模型和采用的分析方法可以较有效地预测基坑开挖对周边环境的影响,为设计和施工提供了重要依据。

Research purposes ： With the increasing depth and size of the excavations, as well as the more complex and sensitive surrounding environmental conditions, more stringent deformation control requirements are needed for the excavation engineering. As a result accurate prediction of the deformation of the excavation and surrounding environments becomes very important. Research conclusions：The design scheme of a deep excavation in close to 6 - storey brick residential building in Shanghai soft soil and the technical measures for surrounding environment projection are described in detail. Then the three - dimensional finite element model is established to simulate the influence of excavation on the adjacent buildings by PLAXIS 3D Foundation program. Calculated deformation of the retaining wall and the settlements of the adjacent buildings are in good agreement with the measured values. The influence of excavation on surrounding environments is effectively predicted by the proposed model and analysis method, which provide an important reference for the design and construction.