某高铁工程桩筏式复合地基工后累积变形分析

某高铁工程沿线分布着大量深厚软弱土层,线路设计时速为350 km,为满足路基的沉降控制值,线路采用多种地基处理方式。其中针对桩筏式复合地基处理的某工点(桩体采用超长预制混凝土管桩),采用数值模拟对其在高速列车运行下的动力响应特性进行了分析,通过数值模拟得到了路基动偏应力分布情况,结合Li和Selig推荐的经验公式,估算了该路基的累积塑性变形。

Analysis on Accumulated Post-construction Deformation of Pile-raft Composite Foundation in a High-speed Railway Project

A large quantity of deep soft soil are distributed along a high-speed railway with the design speed of 350 km/h. Many methods for foundation treatment are adopted for this line in order to meet the control criterion of subgrade settlement. For certain construction site treated by pile-raft composite foundation, (where the pile body was extra-long precast concrete pipe pile,)the dynamic response thereof under operation of high-speed train numerical simulation analysie was made, thus the distribution of dynamic deviator stress in the subgrade was obtained and, combined with the empirical equation recommended by Li and Selig, the plastic deformation accumulated therein was estimated.