抗拔桩变形及对地铁车站结构计算影响分析

Deformation of Uplift Piles and Its Influence on Calculation of Metro Station Structures

目前,对于地铁车站计算模型中抗拔桩的模拟方式存在局限性,不能反映真实的抗拔桩受力变形性状,对于车站结构的计算带来一定的偏差,造成结构配筋不合理。针对这一现状,提出对抗拔桩采用大刚度弹簧进行模拟,建立抗拔桩的荷载传递模型,推导基于轴向Winkler地基模型的抗拔桩弹性解答,得出模拟抗拔桩的弹簧刚度计算公式。在此基础上,将抗拔桩作为大刚度弹簧的计算模型和其他常用的几种抗拔桩模型进行详细说明,通过实例计算,对这几种模型对地铁车站结构的受力变形计算结果进行对比分析,得出各种模型的受力变形差异,为带抗拔桩的车站结构计算提供了指导。

The existing simulation and calculation models of Metro stations cannot reflect the actual deformation of uplift piles,which causes deviations in the calculation of Metro station structures and in turn causes irrational steel bar arrangement of Metro station structures.In the paper,it is proposed that the uplift piles should be simulated by largerigidity spring models.Load transferring model is established for the uplift piles,elastic solution based on axial Winkler model is deduced for the uplift piles,and spring rigidity calculation formulas is obtained for the uplift piles simulated.Regarding uplift piles,comparison and contrast is made between the large-rigidity spring calculation model and other simulation and calculation models,and comparative analysis is made on the calculation results obtained by these models and on the influence of these calculation results on the deformation of Metro stations.In this way,the deformation difference calculated by different simulation and calculation models is obtained.The paper can provide reference for the structural calculation of Metro stations with uplift piles in the future.