徐州某基坑工程钢筋混凝土支撑布设方式研究

Research on Layout Method of Reinforced Concrete Support for a Foundation Pit Project in Xuzhou

钢筋混凝土支撑是基坑工程中常见的一种支撑类型,而工程中常因布设不当造成支撑受力不合理、造价不经济,因此对钢筋混凝土支撑布设方式进行分析具有实际意义。以江苏徐州某深基坑工程为例,采用空间整体协同有限元计算方法,对不同支撑布设形式进行对比分析。计算分析结果表明:角撑重叠区产生了支撑力叠加,致使腰梁受力加大,桩身位移指向坑外,而角撑重叠区彼端则位移指向坑内且较大,基坑四周变形不协同。因此,基坑支撑布设过程中应力求避免交叉重叠,对于一般矩形基坑,宜采用角撑+对撑的形式以期基坑四周协同变形。通过对混凝土支撑布置方式研究,可为类似的基坑工程问题提供参考。

Reinforced concrete support is a common type of support in the deep excavation supporting engineering.However,improper support layout often leads to the unreasonable stress and the uneconomical cost.Therefore,it is of practical significance to analyze the layout of the reinforced concrete support.This paper presents deep excavation project in Xuzhou,Jiangsu Province.The finite element analysis method of the spatial overall coordination is used to compare and to analyze different forms of support layouts.The evaluation and analysis results show that the support force superposition is generated in the corner bracing overlap area,resulting in an increase in the stress of the waler beam,and the displacement of the pile points to the outside of the excavated area,while the displacement at the other end of the corner bracing overlap area points to the inside of the excavated area and is larger,and the deformation around the deep excavation is not coordinated.Therefore,the process of arrangement of the supporting system should avoid the cross overlap.For a general rectangular excavated area,it is suggested using the form of corner bracing plus diagonal bracing to ensure the collaborative deformation around the excavated area.The study of the concrete support arrangement can provide a reference for the similar excavation engineering problems.