桩板结构路基的动力响应分析

桩板结构路基-无砟轨道结构是一种相对较新的结构。因此,结合变形控制条件对桩板结构的匹配和动力特性进行数值模拟分析是很有意义的。本文通过动力响应包括动变形、动应力和基面加速度等分析,讨论地基处理的范围和深度、桩端持力层的刚度等问题。研究表明,增大桩径和增大桩端持力土层的承载力或刚度均是降低变形的有效措施。根据断面竖向变形的影响范围,通过对承台两侧宽5 m、深10 m范围内的地基进行处理,对于减少变形是有效的。此外,本文提出的桩板结构-无砟轨道路基横断面尺寸可供设计参考。

Analysis on Dynamic Responses of Subgrade with the Pile-plank Structure

The unballasted track by the pile-plank structure is a relatively new structure.It is very important to make simulation analysis on the matching and dynamic performance of the pile-plank structure under the controled deformation conditions.This article analyses the dynamic responses including dynamic deformation,dynamic stresses,dynamic acceleration on the basic plane,and so on.This article discusses a series of questions including the scope and depth of ground treatment,the rigidity of the bearing stratum in the tip of pile,and so on.The research shows that the deformation can be reduced effectively by enlarging the pile diameter and increasing the rigidity or the bearing capacity of the bearing stratum in the tip of pile.According to the influence scope of the vertical cross-sectional deformation,it is seen effective to reduce the deformation by strengthening ground in the scope of 5 m on both sides and 10 m in the depth.The cross sectional dimensions of the pile-plank structure/unballasted track in this paper provide reference for design.