基坑环形内支撑平面几何构型与变形特征研究

STUDY ON GEOMETRIC CONFIGURATION AND DEFORMATION CHARACTERISTICS OF CIRCULAR INNER SUPPORT PLANE IN FOUNDATION PIT

近年来环形内支撑支护结构越来越受到岩土设计人员的青睐,相对于其他支护型式,环形内撑有着受力均匀、变形合理、能提供大面积施工面、易拆除等优点。现今对环形内支撑的研究主要为支撑结构的安全性,分析其在基坑开挖过程中受力与变形规律,而对环撑平面几何构型研究相对较少。传统设计人员对于既定的支护类型,往往依靠经验性,在保证安全性与美观性的同时,缺乏对于其几何构型优化考虑,导致造价成本浪费。因此本文主要针对环梁内支撑平面几何构型与变形特征进行研究,依托于实际项目采用MIDAS软件进行数值模拟计算分析,采用3种典型布置方案,分析环撑受力变形特征,得到环撑平面几何构型对基坑变形影响规律,研究结果可为类似工程设计提供经验参考。

In recent years,the ring-shaped internal bracing structure is more and more favored by geotechnical designers,compared with other types of bracing,the annular bracing has the advantages of uniform force,reasonable deformation,large construction area,easy removal and so on.At present,the research of the annular bracing is mainly about the safety of the bracing structure,analyzing the law of the force and deformation during the excavation of the foundation pit,but the research on the plane geometry configuration of the annular bracing is relatively less.The traditional designers often rely on experience for the given support type,while ensuring the safety and aesthetics,lack of consideration for its geometry configuration optimization,resulting in cost waste.Therefore,this paper mainly studies the geometric configuration and deformation characteristics of the inner support plane of the ring beam.Based on the actual project,Midas software is used to carry out numerical simulation and analysis,and three typical layout schemes are adopted,based on the analysis of the deformation characteristics of the ring bracing,the influence of the plane geometry of the ring bracing on the deformation of the foundation pit is obtained.