基于应变梯度理论的粘塑性厚壁圆筒和球壳极限内压分析

基于应变梯度塑性理论，分析了内压作用下厚壁圆筒和球壳的塑性极限荷载．结果表明:圆筒内径在微米量级时，存在尺度效应现象，内径减小，其尺度效应增强；变形越大，影响越大；应变速率敏感指数越大，尺度效应越明显．经典塑性理论结果是当前解的特例．

Limit Analysis of Viscoplastic Thick-Walled Cylinder and Spherical Shell Under Internal Pressure Using a Strain Gradient Plasticity Theory

Plastic limit load of viscoplastic thick-walled cylinder and spherical shell subjected to internal pressure is investigated analytically using a strain gradient plasticity theory.As a result,the current solutions can capture the size effect at the micron scale.Numerical results show that the smaller the inner radius of the cylinder or spherical shell,the more significant the scale effects.Results also show that the size effect is more evident with the increase of strain or strain-rate sensitivity index.The classical plastically-based solutions of the same problems are shown to be a special case of the present solution.