盐渍土地区铁路涵洞基础沉降分析

On railway culvert foundation settlement in saline land area

根据实际工程,以新建锡铁山至北霍布逊地方铁路为依托,针对位于该地区特殊地质条件(高含盐饱和细砂土)下钢筋混凝土箱型涵的修建,开展对青海北霍布逊湖区高含盐饱和细砂土地基条件下涵洞地基处理的关键技术研究。涵洞原地基处理方式为碎石桩基础,后因地质原因及施工条件做出设计变更,采取片石换填的地基处理方式。应用实际观测到的涵洞的沉降变形资料和涵身现场的原位测试、查阅相关资料及反演得到的土性参数,对涵洞采取的两种地基加固方式进行对比分析,并利用有限元软件对其进行数值模拟运算,分析涵洞在不同荷载工况下的沉降变化规律,为盐渍土地区工程的地基处理提供了重要的技术资料。

According to the actual project, based on the practice of newly-built local railway of Xitieshan-North Huobuxun, key technology study is performed on foundation handling under the conditions of lake sand subsoil in the special geological conditions （ high salt saturated fine sand） of reinforced concrete box culvert. Culverts original ground handling method is gravel pile foundation, design changes due to geological reasons and construction conditions, pieces replacement is adopted. The two culverts foundation reinforcement methods adopted were analyzed based on the settlement deformation data, in-situ test and soil parameters. The numeri-cal simulation computation is made by using finite element software to analyze culvert settlement variation in different load conditions for foundation treatment of saline land area, which can provide important technical in-formation for similar project.