高铁沿线地下水位动态变化引发的成层弱透水层固结研究

摘要

采用Laplace变换和传递矩阵法推导高铁沿线地下水位动态变化引发的成层弱透水层固结变形的解析解,通过与ABAQUS数值计算结果对比验证解析解的正确性.利用解析解对某高速铁路沿线成层弱透水层的固结性状进行研究,计算地下水位动态变化下土层的固结变形量、变形速率和超静孔隙水压力随时间的变化,并分析土层压缩模量和渗透系数对土层固结变形的影响.研究结果表明:随着地下水位降低,土层中孔隙水压力逐渐降低,土层固结变形量和变形速率逐渐增加;当地下水位保持稳定后,土层固结变形速率逐渐降低,但土层仍持续较长时间的固结过程;土层压缩模量越大,土层系统总沉降量和沉降速率越小;土层渗透系数越大,土层总沉降量越大,水位稳定后土层系统完成固结的时间越短.%With Laplace transform and transfer matrix method,analytical solutions are derived for consolidation of multi-layered aquitard induced by dynamic variation of groundwater level along high speed railway line.The analytical solutions are then verified through comparisons with the numerical calculation results of ABAQUS.The consolidation performances of multi-layered aquitard along a high speed railway line are studied based on analytical solutions.The settlement,settlement rate and excessive pore water pressure of multi-layered aquitard are calculated,and the effects of compression modulus and permeability of aquitard on the consolidation performances are analyzed.The results show that as the groundwater level declines,the pore water pressure decreases,while settlement and settlement rate are increasing gradually.As the groundwater level remains stable,the settlement rate decreases gradually and the consolidation of multi-layered aquitard still lasts for a long time.The larger the soil compression modulus is,the smaller the total settlement and settlement rate are.The larger the soil permeability is,the larger the total settlement is and the sooner the consolidation of multi-layered aquitard ends.