高速铁路路基动态变形模量分析

Analysis of dynamic deformation modulus for high-speed railway subgrade

通过兰新铁路第二双线路基试验段戈壁填料现场填筑试验,分析了动态变形模量Evd与路基填料以及与填土压实质量的关系。研究表明,Evd与静态变形模量Ev2的相关性很好,Evd与地基系数K30的相关性较差。通过ADINA三维动态有限元数值分析并结合现场检测结果,对Evd值的影响因素进行了分析。结果表明,Evd理论上与动模量Ed完全线性相关,Evd与Ed的相关性表达式与动摩擦角及动黏聚力有关;当填土动黏聚力较小时,Evd值随动黏聚力及动摩擦角的增大而增大,当动黏聚力增大到一定值以后,Evd值不再随动黏聚力及动摩擦角的增大而变化;Evd值与土体在冲击荷载作用下的抗剪强度有关,在既定的Ed下,当抗剪强度较小时,Evd值随抗剪强度的增大而增大;当抗剪强度达到一定值后,Evd值不再随抗剪强度的增大而变化。

Through the on-site filling test in the subgrade test section of Lanzhou-Xinjiang Railway two-line in desert area,the relationship between dynamic deformation modulus Evd and subgrade filler as well as the compaction quality of the filler is analyzed,which shows a lack of correlation between Evd and K30（ground coefficient）,while Evd is well correlated to Ev2（static modulus of deformation）.After analyzing the influence factors of Evd by combining the numerical calculation of ADINA（three-dimensional dynamic finite element software） with field test,the findings indicate the following conclusions.Complete linear correlation exists between Evd and Ed（dynamic modulus） in theory,their correlation formula has something to do with dynamic angle of internal friction and dynamic cohesion.When the filler dynamic cohesion keeps low,Evd increases with the dynamic cohesion and dynamic angle of internal friction;while Evd will not change with them when the filler dynamic cohesion is large enough.Also,Evd relates to the shearing strength of soil under the impact load.With Ed stays established,Evd increases with the shearing strength which is relatively low,but when the shearing strength reaches a certain value,Evd will no longer change.