Abstract: Expansive soil has the deformation characteristics of water absorption expansion and water loss shrinkage, which makes the expansive soil section very easy to produce diseases such as the arch deformation of the track and the instability of the slope. It is an effective method to solve the problem that the foundation reinforcement in the expansive soil section is based on the Nanchuan North Station construction site, and the key technology of the foundation reinforcement in the expansive soil section is discussed. The relevant mechanical properties of the expansive soil foundation and the key technical problems involved in the construction of CFG piles are mainly studied, and the bearing capacity and settlement of the foundation after the reinforcement of the CFG piles are analyzed. The results will provide technical reference for the similar projects.

Key words: expansive soil foundation, subgrade disease, CFG pile reinforcement, basic bearing capacity

摘要： 膨胀土具有吸水膨胀、失水收缩的变形特性,导致膨胀土区段极易产生轨道上拱变形和边坡失稳等危害。对膨胀土区段地基加固是解决该问题的有效方法,依托南川北站工点,对膨胀土区段地基加固关键技术进行了讨论。重点研究了工点膨胀土地基的相关力学性质以及CFG桩施工涉及的关键技术问题,并对CFG桩加固后地基承载力和沉降量进行分析,定量研究CFG桩的加固效果,为相似工程提供一定的技术参考。

关键词: 膨胀土地基, 路基病害, CFG桩加固, 基础承载力