季节冻土区高速铁路路基保温措施效果研究

为减小季节性冻土区路基冻胀对高速铁路无砟轨道平顺度的影响,采用路基保温措施进行室内模型试验,对不同厚度保温板覆盖下路基AB组填料在多个冻融循环过程中的温度及变形规律进行了试验与分析.室内模型试验结果显示,XPS保温板具有良好的保温隔热作用,厚度越大,保温效果越好,保温措施有效控制了哈齐线路基AB组填料的冻胀变形,同时也降低了其残余变形.根据室内试验结果,采用20 cm厚保温板的保温措施在哈齐线路基试验段进行现场试验.试验结果表明,该保温措施有效控制了左右线轨道板下方区域的冻胀变形,保证了轨面平顺度.

Study on insulation measures of high-speed railway subgrade in seasonally frozen soil region

In order to reduce the influence of embankment frost heaving on high-speed railway unballasted track smoothness in seasonal frozen soil regions,a laboratory model test was conducted using embankment insulation measure. Different thicknesses of insulation boards were covered by fillers of Groups A and B,and tested under freeze-thaw cycles,then deformation and temperature of the fillers were measured and analyzed.The laboratory model test results indicated that the thermal insulation effect of XPS insulation board was excellent,and the thic-ker the board,the better the effect.The insulation measure not only can decrease the frost heaving deformation of the filler in Ha-Qi railway passenger dedicated line effectively,but also can reduce the residual deformation. According to the laboratory test results,using heat preservation measure with 20-cm thickness insulation board,a field test was carried out in an embankment section of Ha-Qi Railway passenger dedicated line.The test results show that the heat preservation measure would be able to effectively control the frost heaving deformation in the track plate region of the left and right lines,which would guarantee the railway surface smoothness.