高铁荷载作用下基床填料的动三轴模量试验研究  

Triaxial Tests on Dynamic Elastic Modulus of Subgrade Fillers under High-speed Railway Loading

作　　者：刘昆林[1,2,3] 杨贵[1,2] 许建宝[1,2] 

机构地区：[1]河海大学安全与防灾工程研究所 [2]河海大学岩土力学与堤坝工程教育部重点试验室 [3]中国人民解放军91039部队

出　　处：《防灾减灾工程学报》2015年第5期666-673,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(U1134207;51479059)资助

摘　　要：依据高铁路基基床的工作条件,推导出室内三轴试验模拟列车荷载的围压范围为10~150kPa,频率范围为1~5Hz。在此基础上开展高铁基床填料AB组料动三轴试验研究,分析了列车荷载下围压、压实度、加载频率对AB组料动弹性模量的影响。试验研究表明：AB组料的动应力—动应变关系具有明显的非线性特征和应变软化特征,动弹性模量的倒数与动应变曲线基本呈线性关系,说明AB组料的动本构关系符合Hardin双曲线模型。动弹性模量随围压的增大而增大;随压实度的增大,动弹性模量呈非线性增大;加载频率对动弹性模量有一定的影响,当应变小于0.05%时频率对动弹性模量影响较大,但应变超过0.05%时,频率的影响可以忽略。Group AB filler is an important part of high-speed railway subgrade bed packing.The dynamic deformation characteristics have important roles for the normal operation of the highspeed railway.Based on high-speed railway subgrade bed working conditions,the confining pressure which ranging from 10 kPa to 150 kPa and loading frequency which ranging from 1Hz to 5Hz were deduced in dynamic triaxial tests.On the basis of this study,the dynamic elastic modulus of high-speed railway subgrade group AB filler was studied.The influences of confining pressure,compaction and loading frequency on dynamic elastic modulus were analyzed under the train loading.The experimental results show that relationship between dynamic stress and dynamic strain of group AB filler has obvious nonlinear and strain softening characteristics,and the reciprocal of dynamic elastic modulus and dynamic strain curve shows a linear relationship,indicating that the dynamic constitutive relations of group AB filler can be analyzed by Hardin hyperbolic model.Dynamic elastic modulus increases with the confining pressure increasing;and with the degree of compaction enhancing,dynamic elastic modulus increases nonlinearly,and the loading frequency has some influence on the dynamic elastic modulus.When the strain is less than0.05%,the influence of frequency on dynamic elastic modulus is greater.But when the strain is greater than 0.05%,the influence of frequency can be ignored.

关 键 词：AB组料 列车荷载 动三轴试验 动弹性模量 

分 类 号：TU352.1[建筑科学—结构工程]