According to the elastic plastic theory in strain space, the constitutive equation on the condition of triaxial test is deducted, which adopts associative flow rule and Mises yield function.

• 本文基于应变空间的基本的弹塑性本构方程式，采用Mises剪切屈服准则及相关联流动法则，推导出三轴条件下的本构关系式。