Finite element implementation of strain-hardening Drucker-Prager plasticity model with application to tunnel excavation

作     者：K.Liu S.L.Chen 

作者机构：Department of Civil&Environmental EngineeringLouisiana State UniversityBaton RougeLAUSA 

出 版 物：《Underground Space》 (地下空间（英文）)

年 卷 期：2017年第2卷第3期

页      面：168-174页

核心收录：

学科分类：07[理学] 0818[工学-地质资源与地质工程] 0815[工学-水利工程] 0813[工学-建筑学] 0814[工学-土木工程] 0701[理学-数学] 

主　　题：Strain-hardening Drucker-Prager model Finite element method UMAT code Tunnel excavation 

摘      要：This paper presents a finite element implementation of a strain-hardening Drucker-Prager model and its application to tunnel excavation.The computational model was constructed based on the return mapping scheme,in which an elastic trial step was first executed,followed by plastic correction involving the Newton-Raphson method to return the predicted state of stresses to the supposed yield surface.By combining the plastic shear hardening rule and stress correction equations,the loading index for the strain-hardening Drucker-Prager model was solved.It is therefore possible to update the stresses,elastic and plastic strains,and slope of the yield locus at the end of each incremental step.As an illustrative example,an integration algorithm was incorporated into ABAQUS through the user subroutine UMAT to solve the tunnel excavation problem in strain-hardening Drucker-Prager rock formations.The obtained numerical results were found to be in excellent agreement with the available analytical solutions,thus indicating the validity and accuracy of the proposed UMAT code,as well as the finite element model.