基于可靠度的基坑桩锚支护优化设计

根据现实基坑工程中确定性方法存在的不足和缺陷,将可靠度理论运用到基坑桩锚支护优化设计中,建立了施工结构各元件可靠度约束条件下的最小化结构费用优化模型.桩锚支护可靠度约束按照抗倾覆破坏稳定模式、抗坑底隆起稳定模式、抗整体失稳模式三种约束模式分别考虑.根据具体的破坏模式建立了功能函数,结合具体的工程实例,采用JC法计算了不同模式的可靠度指标.计算中编制了Matlab程序,予以实现具体的优化设计.研究结果表明,应用可靠度理论进行基坑优化设计是可行且有效的.

Optimization Design of Foundation Pit Pile-anchor Supporting Structure Based on Reliability Theory

According to the shortcomings and deficiencies in the real excavation work,the minimum optimization model for the structure cost based on the reliability of all construction components is established by applying the reliability theory to the optimization design of retaining structure of deep foundation.The models of the support reliability constraints can be divided into three：anti-o-verturning stability model;resistant heave stability mode and entire instability mode.In accord-ance with the specific fail model,the functional function is established,calculating the reliability index by using the JC method in real construction proj ects and programming MATLAB applica-tion to achieve the optimal design.The results show that it is feasible to apply the reliability theo-ry to the optimization design of retaining structure of deep foundation pit.