CONSTITUTIVE MODEL OF POROUS ELASTOVISCOPLASTIC MATERIALS SUBJECTED TO SHOCK--PART II:DISTORSIONAL BEHAVIOR OF POROUS ELASTOVISCOPLASTIC MATERIALS
弹粘塑性孔隙介质在冲击荷载作用下的一种本构关系--第二部分:弹粘塑性孔隙介质的畸变行为

Continuing the study performed in the first part put in the issue 2003-9 of this journal,the second part of the paper researches the distorsional behavior of porous elastoviscoplastic materials subjected to shock. The influence of strain rate on material strength is considered,and a unified strain rate dependent strength model of competition between thermal activation mechanism and macro-viscosity mechanism is proposed. The influences of stress state,strain hardening,distorsional deformation damage,and damage related with porosity change are considered. And furthermore,on the basis of thermal activation mechanism,a relaxation type relation between distorsional stress tensor and distorsional strain tensor is given,and the model follows the second thermodynamic law.