冰与海洋结构相互作用力的弹塑性分析──冰载荷的塑性极限分析

The Plastic Limit Analysis of Ice Load

以Ｒａｌｓｔｏｎ提出的冰本构模型为基础，给出塑性应力场解的形式对平压头接触问题给出应力场的构造，从而计算出冰载荷的塑性极限压力与Ｒａｌｓｔｏｎ的结果相比较，本文采用的方法简便易行，并能清淅地看出塑性应力的分布如果采用剪切破坏准则。

The load in ice failure is usually taken in the design of arctic structures.One of the most widely used yield conditions in sea ice load calculations was proposed by Ralston who presented a plastic limit analysis to relate the compressive strength to indentation pressure for the columnar-grained ice sheets.Based on the constitutive law proposed by Ralston,the formulation of the plastic stress field solution is obtained.The plastic limit pressure can be calculated from the stress field.Compared with the Ralston's results,the method proposed in this paper is simple and easy.The distribution of the plastic stresses can be seen clearly.Using the criteria of the shear failure,the opening angle is given when an ice sheet moves against a rigid punch.