An improved creep model for unsaturated reticulated red clay  

作　　者：Chuang Zhang Junhui Zhang Jianzhong Li 

机构地区：[1]Key Laboratory of Special Environment Road Engineering of Hunan Province,Changsha University of Science and Technology,Changsha,410114,China [2]School of Traffic and Transportation Engineering,Changsha University of Science and Technology,Changsha,410114,China [3]Department of Architecture and Civil Engineering,City University of Hong Kong,China [4]School of Geosciences and Info-Physics,Central South University,Changsha,410083,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2024年第11期4754-4768,共15页岩石力学与岩土工程学报（英文）

基　　金：supported by the National Science Fund for Distinguished Young Scholars (Grant No.52025085);the National Key Research and Development Program of China (Grant No.2021YFB2600900);the Open Fund of Key Laboratory of Special Environment Road Engineering of Hunan Province,China (Changsha University of Science and Technology) (Grant No.kfj230606).

摘　　要：Establishment of a creep model is an important method to analyze the relationship between soil creep deformation and time,and the element model is widely used for studying soil creep.However,the element creep model is employed for fitting saturated soil,and the mechanical element model is generally linear,which cannot well fit the nonlinear deformation of the soil with time in practice.The creep process of the soil is not only time-dependent,but also related to the deviatoric stress level.Therefore,the fractional calculus theory and a parameter n reflecting the effect of deviatoric stress level on the creep properties of the soil were introduced into the element model,and the fractional qBurgers creep model was established by using the fractional Koeller dashpot and Caputo fractional calculus.The proposed model was used to fit the triaxial test data of reticulated red clay under different net confining pressures and matric suctions by unsaturated triaxial apparatus.The proposed model can well describe the nonlinearity of unsaturated reticulated red clay,has memory and global correlation to the creep development process of unsaturated reticulated red clay,and has clear physical meaning.The functional relationships of the model parameters with the matric suction,net confining pressure and deviatoric stress level were deduced,so that the creep curves of unsaturated reticulated red clay can be obtained for any conditions,which is of great value for the study of unsaturated soils.

关 键 词：Fractional calculus Creep model BURGERS Parameter study Unsaturated reticulated red clay 

分 类 号：TU45[建筑科学—岩土工程]