地铁列车移动荷载作用下饱和软黏土地基动力响应及长期累积变形

Dynamic Response and Long-term Accumulation Deformation of Saturated Soft Clay under Repeated Load of Subway Trains

为了研究地铁列车荷载反复作用下饱和软黏土地基的动力响应和长期累积变形,通过进行室内固结不排水动三轴试验,得到了地基累计变形计算参数,并建立了车辆-轨道相互作用动力学模型,对列车反复荷载作用下软土地基的动力响应和累积塑性变形进行研究。研究结果表明:土体中的累积塑性应变随深度逐渐减小,同样的深度位置,累积塑性应变随荷载作用次数增加而增加;在车辆荷载作用的早期,累积变形的增长速率最大,随着荷载次数的增加,累积变形的增长速率逐渐减小,且累积变形曲线有明显的拐点。

In order to study the dynamic response and long-term cumulative deformation of saturated soft clay under repeated loading of subway train,consolidation undrained triaxial tests were carried out to get the cumulative calculation of foundation deformation parameter.A dynamic model of vehicle-orbit interaction was established to study the dynamic response and cumulative plastic deformation of soft clay under repeated loading.The results show that,in the same depth position,the cumulative plastic strain increases with the increase of the number of loads.In the early stage of vehicle load,the cumulative growth rate of deformation is the largest.With the increase of load times,the cumulative growth rate of deformation decreases gradually,and the cumulative deformation curve has a typical inflection point.