环形刚框的塑性分析

本文在理想弹-塑性材料和应变平面分布的基础上,建立塑性铰概念,对环形刚框进行了塑性分析。通过塑性铰的形成,列补充方程,用静力学方法解出一超静定度数为3环形刚框所能承受的极限载荷。与弹性计算方法计算结果相比较:环形刚框所能承受的极限载荷有很大提高。这一计算实例显示出:由于考虑了材料的塑性性能和载荷在结构中的重新分布,塑性分析可以更合理的计算结构强度,更充分地利用材料,减轻结构重量。而这些对于飞机设计来说都是非常重要的。

Plastic Analysis of the Circular Frames

In this article, we have built up the concept of plastic hinge and made a plastic analysis of the three degree indeterminate circular frame on the basis of ideal elastic-plastic material and strain plane-distribution over cross sections. By means of supplemental equa- tions set out through the medium of formed plastic hinges, we have solved the ultimate load of the circular frame, using the static mechanics method. Compared with the results of the elastic analysis method, the ultimate load is greatly increased. This calculating example shows that the plastic analysis makes it possible to make fuller use of materials, to arrive at a more accurate calculation of the structure strength and to lighten the structure weight, just because the plastic performance of materials and load redistributions are taken into consideration. This is very important for aircraft structure design.