含水率与轻型动力触探N_(10)对既有重载铁路路基压实度指标变化关系研究

Research on existing overloaded railway subgrade compaction index changing in relation to N_(10) and moisture content separately

通过朔黄铁路现场路基压实度指标地基系数K_(30)、动弹性模量E_(vd)、二次回弹模量E_(V2)、二次回弹模量与1次回弹模量比E_(V2)/E_(V1)、轻型动力触探击数N_(10)测试实验数据和含水率w测试实验数据。基于以上数据研究含水率对地基压实指标K_(30)、E_(vd)、E_(V2)、E_(V2)/E_(V1)和轻型动力触探击数N_(10)之间的变化关系。并且提出动力触探击数N_(10)估算K_(30)、E_(V2)、E_(V2)/E_(V1)、E_(vd)的估算方法。通过实例验证得出该估算方法的适用条件:(1)为含水率8%~14%,且以粉质黏土为主体填料的C组填料;(2)锤击数范围17~30击。而且在对E_(V2)/E_(V1)的估算时,需要谨慎对待,注意误差修正。研究结果表明:该方法对于既有重载铁路C组填料路基的快速检测评估具有十分重要的意义。

The railway subgrade compaction indexs of foundation coefficient K（30）,dynamic elastic modulus E（vd）,the second rebound modulus E（V2）,the second resilient modulus and a second resilient modulus E（V2）/E（V1）,light dynamic penetrationN（10）,and moisture content w were obtained by field test in SHUHUANG railroad.Based on the above datas,The changing relationship of foundation compaction indexes—K（30）,E（vd）,E（V2）,E（V2）/E（V1）,N（10）,and moisture content w separately were researched.The mentioned estimation methods in K（30）,E（V2）,E（V2）/E（V1）,E（vd）being estimated by use of N（10） were proposed.The applicable conditions of estimation method was obtained through examples verification：（1）the silty clay as main filler was belong to c group,the moisture content being 8%~14%;（2） N（10） range was 17~30,and E（V2）/E（V1） was estimated to fix error.The results were shown：The method proposed was great importance,for the existing heavy rail roadbed filler Group Crapid detection and evaluation.