紧邻桥台开口型基坑设计方案对比分析

以福州地铁1号线洗马桥改造工程为背景,采用三维数值模拟方法,研究了紧邻桥台开口型基坑支护设计中的水平支撑设置问题。重点分析了水平支撑与桥台相连或不相连的两种方案下,围护结构的水平位移、围护结构的弯矩、水平支撑的轴力以及桥台的水平位移。通过对比,认为穿越桥台对撑方案比桥台直接支撑方案要更为合理,并以此作为实际设计施工方案。工程监测数据所反映的规律与数值模拟结果基本一致,这也佐证了穿越桥台对撑方案的合理性。研究结果可为类似的开口型基坑设计提供参考。

Comparative Analysis on Design Scheme of Open Type Foundation Pit Adjacent to Abutment

Taking the reconstruction project of Ximaqiao on Fuzhou Metrol Line 1 as the background,this paper,by three-dimensional numerical simulation,studied the setting of horizontal support in the bracing design for open type foundation pit adjacent to abutment,wherein in the two cases,i.e.the horizontal support connected or not connected to the abutment,the bracing’s horizontal displacement and bending moment,the horizontal support’s axial force and the abutment’s horizontal displacement,were analyzed.Through comparison,it was considered that through-type buttressed abutment is more rational than direct support scheme so that it was put into practice.The rules reflected by the engineering supervision data agree with the result from the numerical simulation substantially,which proves the rationality of the through-type buttressed abutment.The study result may be taken as the reference to similar design of open type foundation pit.