CRTSⅢ型板式无砟轨道下路基的累积变形  

Accumulative Deformation of Subgrade Under CRTS Ⅲ Slab Track

作　　者：李扬波[1] 张家生[1] 朱志辉[1,2] 王晅[1,2] 石熊[1] LI Yangbo;ZHANG Jiasheng;ZHU Zhihui;WANG Xuan;SHI Xiong(School of Civil Engineering,Central South University,Changsha 410075,Hunan,China;National Engineering Laboratory for High Speed Railway Construction,Central South University,Changsha 410075,Hunan,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中南大学高速铁路建造技术国家工程实验室,湖南长沙410075

出　　处：《华南理工大学学报（自然科学版）》2019年第3期135-142,共8页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51678576;51378511;51378514)~~

摘　　要：为研究CRTSⅢ型板式无砟轨道下路基在设计使用年限内的累积变形规律,设计了路基累积变形试验方案.介绍了CRTSⅢ型板式无砟轨道-路基足尺模型试验平台,并在该试验平台上开展了1亿次循环荷载试验.试验结果表明:路基动应力受循环荷载作用轴次的影响很小;随着列车荷载作用轴次的增加,路基累积变形在加载初期增长较快,随后增长速率逐渐变小,当加载轴次达到350万次后趋于稳定,在1亿次加载后最终稳定值为3.38 mm;基床表层、基床底层、路基本体和地基累积变形分别占路基总体累积变形的68.93%、16.86%、8.88%、5.33%.最后,基于模型试验结果提出了高速铁路路基累积变形预测模型,可为建立起符合实际的列车长期重复荷载作用下高速铁路路基累积变形计算方法提供参考和借鉴.An experimental scheme for the accumulative deformation of subgrade was proposed to study the accumulative deformation law of the subgrade under CRTSⅢslab track during the design service life.A full-scale CRTSⅢslab track-subgrade system was introduced,and a 100 million cyclic loading experiment was carried out on the test platform.Test results show that the number of cyclic loading has small influence on dynamic stress of the subgrade;with the increase of cyclic loading times,subgrade accumulative deformation grows fast in the initial stage,and after that the rate of growth gradually decreases;when the cyclic loading reaches 3.5 million times,it tends to be stable,and after 100 million loading,the final stability value reaches 3.38 mm.The accumulative deformation of the surface layer of subgrade,bottom layer of subgrade and foundation respectively accounts for 68.93%,16.86%,8.88%,5.33%of the total accumulative deformation of the subgrade.Finally,an accumulative deformation prediction model was proposed based on the test result,which can provide reference for the establishment of a practical calculation method for the acumulative deformation of high-speed railway subgrade under long-term repeated train loads.

关 键 词：高速铁路 路基 足尺模型试验 循环荷载 累积变形 

分 类 号：TU43[建筑科学—岩土工程]