朔黄重载铁路路桥过渡段加固路基的检测与分析

在既有重载铁路中,路基、桥梁与涵洞等构筑物连接的路桥过渡段是线路的薄弱环节,对其进行检测,评估路基承载力是保证线路平顺度和列车安全、平稳运行的关键.采用地基系数K30试验、轻型动力触探试验和室内试验对加固后的朔黄铁路第170号桥路桥过渡段质量进行了检测.试验结果表明：①地基系数K30能够直观地表征路基刚度及承载能力,加固后朔黄铁路170号桥路桥过渡段不同位置处的地基系数K30值提高15%～40%左右;②地基系数K30和轻型动力触探试验结果N10有显著的线性关系,压实系数与地基系数K30不存在相关性;③既有重载铁路路桥过渡段路基质量检测应进行大量的轻型动力触探试验,再辅以地基系数K30试验进行校核,对提高检测的工作效率、降低检测成本、减少检测工作对既有线运营的干扰有重要的意义.

Detection and analysis of subgrade reinforced in bridge-subgrade transition section of Shuo-Huang heavy haul railway

Bridge-subgrade transition section is a weak link between roadbed and bridges or culverts in existing heavy haul railway. To detect and evaluate the roadbed bearing capacity is the key to ensure the smooth of railway and comfort of moving train. In this article, Number 170 Bridge＇s bridge-sub- grade transition section of Shuo-Huang railway is detected by K30 plate loading test, light dynamic penetration test and laboratory test. The results indicate that （1）Foundation coefficient K30 can intu- itively characterize the subgrade stiffness and bearing capacity. The reinforced roadbed＇ s foundation coefficient K30 has increased from 15 % to 40 % in different positions of bridge-subgrade transition sec- tion. （2） There is good correlation between foundation coefficient K30 and Light Dynamic Penetration N10. Compaction coefficient and foundation coefficient K30 has no correlation. （3） The bridge-subgrade transition section detecting of existing heavy haul railway should do enough light dynamic penetration test, and complementary with foundation coefficient K30 standard. It has important significance for improving the detection efficiency and reducing detection cost and the disturbance of detection to exist- ing railway operation.