甬台温铁路线某段桩-网复合地基的动力变形分析

针对甬台温铁路某段地基结构,通过拟合列车荷载时程函数,运用Midas/GTS NX软件建立轨道-路堤-桩网复合地基三维动力耦合模型,分析了软土区的碎石注浆桩-网复合地基在列车高速行驶过程中产生的地基土体动应力分布规律以及变形趋势。结果表明:铁路桩-网复合地基在列车荷载作用下产生的竖向动应力主要集中在路堤范围内,且沿着深度方向逐渐减小,但在桩端处放大;地基累积变形主要集中在前期,之后随着振动次数的增加而趋于稳定,这对于轨道不平顺性修正具有现实意义。

Dynamic Deformation Analysis of Pile-net Composite Foundation for Ningbo-Taizhou-Wenzhou Railway

Aiming at the foundation structure of Ningbo-Taizhou-Wenzhou Railway, this paper. proposes train load function and adopts Midas/GTS NX software to establish three-dimensional coupling model of track-embankment-pile net composite foundation, analyze the foundation soil dynamic stress distribution law and changing trend of gravel grouting pile-net composite foundation in soft soil area on the high-speed driving process. The results show that vertical dynamic stress of railway pile-net composite foundation under the train load is mainly concentrated on the scope of embankment, decreasing along the depth direction, but amplifying at the pile end. The foundation accumulative deformation is mainly in the early stage and then tends to be stable with the increasing of vibration times, which has practical significance for modifying unsmoothness of track.