华北地区高速铁路松软土地基变形特性

Deformation Characteristics of High Speed Railway Loose and Soft Foundation in North China

华北地区是我国松软土分布的主要地区之一,松软土地基条件下路基工后沉降控制是高速铁路设计中的关键。本文依据工程地质条件将华北地区松软土划分为Ⅰ～Ⅴ共5个分区,依据已建和在建铁路工程地质数据对松软土的物理、力学指标进行了统计分析,并通过理论计算和数值模拟对松软土地基变形特性加以研究。结果表明：Ⅱ区的工后沉降及总沉降均最小,其次是Ⅲ区、Ⅳ区,Ⅴ区最大;在路堤填筑工况（不考虑列车荷载的影响）下,0～6个月期间沉降发展较为迅速,填筑完成后沉降仍在缓慢发展,路基填筑后约4年沉降基本稳定;在列车荷载工况（考虑列车荷载的影响）下,0～6个月期间内沉降发展较为迅速,在路基填筑后约3年沉降基本稳定。

The north China area is one of the main areas with soft soil. Subgrade foundation setdement control is key to the design of high speed railway. Based on engineering geological conditions, north China loose and soft soil area was classified as I - V 5 zones. According to engineering geological data of constructed and constructing railways, soft soil physical and mechanical indexes were statistically analyzed. Through theoretical calculation and numerical simulation soft soil foundation deformation characteristics were studied. The results showed that zone II settlement was minimum, followed by Zone IlI, 1V and V. Under the embankment gravity load, during the period of 0 -6 months foundation settlement developed rapidly, till about 4 years later settlement became stable. Under the embankment gravity load and train load, during the period of 0 -6 months settlement developed rapidly, till about 3 years later settlement became stable.