Numerical implementation of suction-dependent resilient modulus constitutive model for subgrade granular material  

路基粒料吸力依赖回弹模量本构模型的数值实现（英文）

作　　者：Liao Gongyun Chen Huaqing  Sun Peixiang 廖公云;陈华庆;孙培翔(东南大学交通学院,南京210096)

机构地区：[1]School of Transportation,Southeast University,Nanjing 210096,China

出　　处：《Journal of Southeast University(English Edition)》2018年第2期251-258,共8页东南大学学报（英文版）

基　　金：The Science and Technology Project of China Communications Construction(No.2015-ZJKJ-26)

摘　　要：In order to investigate the suction-dependent properties of subgrade granular material and its effect on pavement responses,coupled hydro-mechanical simulations were conducted in Abaqus.A suction-dependent resilient modulus model was integrated into the commercial finite element(FE)code Abaqus by developing a user-defined material(UMAT)subroutine.The developed model was validated by triaxial test results under different suction conditions and good agreement was achieved.A three-dimensional(3D)FE pavement model was established and the suction-dependent properties of subgrade granular material was characterized by the developed constitutive model.Hydro-mechanical pavement responses subjected to three moisture states and the falling weight deflectometer(FWD)load were calculated.Simulation results reveal that the resilient modulus of subgrade granular material is sensitive to suction and stress states;high groundwater table decreases the overall resilient moduli of subgrade structure due to suction reduction,leading to the increase of the maximum surface deflection,the tensile strain at bottom of the surface layer,compressive strain on top of subgrade,and consequently,deterioration in pavement performance.为了研究路基粒料的吸力依赖性及其对路面响应的影响,在Abaqus中进行了水力学耦合模拟.通过开发用户自定义材料子程序(UMAT),将一个吸力依赖的回弹模量模型整合到商用有限元软件Abaqus中.使用不同吸力条件下的三轴实验结果验证了开发的模型,模拟与试验结果具有良好的一致性.建立了一个三维有限元路面模型,并用开发的本构模型表征路基粒料的吸力依赖性.计算了处于3种不同湿度状态和FWD荷载作用下的路面水力学响应.模拟结果表明:路基粒料的回弹模量对吸力及应力状态具有敏感性;由于吸力下降,高地下水位降低了路基结构整体回弹模量,导致路表最大弯沉、面层层底拉应变、路基顶面压应变增大,相应造成路面使用性能恶化.

关 键 词：resilient modulus model SUCTION pavement model finite element granular material 

分 类 号：U416.1[交通运输工程—道路与铁道工程]