气态水迁移作用对季冻区高铁路基粗填料含水率的影响

Influence of vapor water migration on moisture content of coarse filler of high-speed railway sub-grade in seasonal frozen area

为研究不同气态水迁移类型对季冻区高速铁路路基粗填料含水率的影响,以哈尔滨地区某新建高速铁路为研究对象,对路基粗填料进行气态水迁移试验,分析不同初始含水率、温度梯度、补水条件、隔水措施条件下粗填料的含水率变化情况。结果表明:两类气态水迁移模式下粗填料含水率均会上升,提高初始含水率与温度梯度都将促进水分的迁移;第一类气态水迁移模式仅产生一个含水率峰值,峰值含水率约为3.5%~6.1%;第二类气态水迁移模式下,除初始含水率为0外将产生两个含水率峰值,隔水膜处含水率约为8.2%~42.7%,第二类气态水迁移模式造成的水分积聚远超第一类,第二类气态水迁移是粗填料含水率上升的重要因素;阻断补水条件或设置隔水层能够起到降低最终含水率的作用。

This paper attempts to investigate the influence of different types of gaseous water migration on the moisture content of coarse filler of high-speed railway sub-grade in seasonal frozen area.By taking a new high-speed railway in Harbin as research object,the study involves conducting gaseous water migration test on the coarse filler of sub-grade,and thereby analyzing the moisture content changes of coarse filler under different conditions of initial moisture content,temperature gradient,water replenishment conditions and water insulation measures.The results show that the moisture content of coarse filler increases under two kinds of gaseous water migration modes,and the increase of initial moisture content and temperature gradient can promote the migration of moisture,which shows with only one peak water content produced under the first type of gaseous water migration mode within 3.5%-6.1%;with two water content peaks under the second type of gaseous water migration mode within 8.2%-42.7%,except for the initial water content of 0,which concluded that the water accumulation caused by the second type of gaseous water migration mode is far more than that of the first type,and the second type of gaseous water migration is an important factor in the increase of water content of coarse filler.Thus,blocking water supply conditions or setting the water barrier can reduce the final water content.