The theory of slip-line field is an effective method for problems of planestrain of perfect plastic solids, and the circle-fan field is used frequently.
滑移线理论是解刚塑性平面应变间题的一种有效方法，而圆扇形场则是常使用的。
2
The crack tip stress-strain field of elastic-plastic materials are analysed by finite element method in the plane stress condition.
用有限元方法对平面应力条件下弹塑性材料的裂纹尖端应力应变场进行了计算。
3
The variation is smaller in plastic relaxation than the elastic one under the same in-planestrain.