膨胀力表征非饱和膨胀土强度特性的试验研究  

The experimental study on the expansion force characterizing unsaturated expansive soil strength properties

作　　者：张金存[1] 程谦恭[1] 李星[1] 姚远[1] 罗浩 

机构地区：[1]西南交通大学地球科学与环境工程学院,四川成都610031

出　　处：《铁道科学与工程学报》2016年第9期1702-1710,共9页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(41502289;41530639;41372292)

摘　　要：为了研究非饱和膨胀土的膨胀力代替基质吸力表征抗剪强度的可行性,开展南宁重塑非饱和弱膨胀土室内土-水特性试验、抗剪强度试验、膨胀力试验等一系列试验研究。研究结果表明:基于Fredlund and Xing模型对土水特征曲线进行拟合,确定土-水特征预测方程,建立基质吸力与抗剪强度及膨胀力间的相互关系;在确定基质吸力换算依据的基础上,建立膨胀力与强度关系的数学模型;改进非饱和膨胀土抗剪强度预测方程,得出用膨胀力代替基质吸力进行抗剪强度预测的方法,并验证可行;确定南宁高速铁路路堤填筑现场的强度预测方程,可为高速铁路路堤填料的强度预测提供参考。研究结果有一定的工程应用价值。In order to study the feasibility of that the expansion force of unsaturated expansive soil is used as the substitute of matric suction to characterize shear strength, soil-water characteristics test, shear strength test and swelling force test of Nanning unsaturated expansive soil samples were carried out.Some results were achieved 1） based on the Fredlund and Xing model, the soil-water characteristic prediction equation was obtained, thus, the relationship between matric suction and shear strength was built; 2） after determining the baseline of matric suction conversion, the mathematic model of expansion force and shear strength was built ; 3 ） the way of using ex-pansion force instead of matric suction to predict the shear strength was obtained by modifying the prediction equation of unsaturated expansive soil, besides, the feasibility was confirmed; 4 ） the shear strength prediction e-quation of embankment of Nanning high speed railway was built,which is valuable to the construction of embankment of high speed railways.These results may be useful to the high speed railway construction.

关 键 词：非饱和膨胀土 基质吸力 膨胀力 抗剪强度理论 

分 类 号：U416[交通运输工程—道路与铁道工程]