Lee极值原理与结构的大挠度塑性动力响应

LEE'S EXTREMUM PRINCIPLE AND THE LARGE DEFLECTION RESPONSE OF DYNAMICALLY LOADED PLASTIC STRUCTURES

本文介绍了利用Lee 极值原理确定结构的大挠度塑性动力响应的数值方法,给出了在均布冲击载荷作用下的理想刚塑性门形框架的大挠度进化模态解,指出如果模态形式取得合适,可使进化模态解接近于真实解.这样得到的门形框架的大挠度模态解与文献[8]中的实验结果和文献[9]中的大挠度完全解都符合得很好.

An approximate method based on Lee's extremum principle is introduced to study the large deflec-tions of dynamically loaded plastic structures.As an example,the evolutionary mode of an impulsivelyloaded rigid-perfectly plastic portal frame is determined and then compared with the experimental re-sults[8]and with the large deflection complete solution obtained previously[9].It is found that the evo-lutionary modal solution may approach the complete solution if the modes are appropriately chosen.