结构动力稳定性判定新准则

Novel Criterion for Identification of Dynamic Stability of Structures

摘要:

利用非线性弹簧模型分析了静力失稳与动力失稳的区别，指出拟静力刚度准则不能用于判定结构动力稳定.给出了结构动力系统特征能量的概念，发现结构动力失稳源于结构特征能量超过输入到结构中的总能量，由此提出了一种判定结构动力稳定性的新准则.实例分析表明,本文建议的准则可以准确分析并判定结构在任意动力荷载激励下的动力失稳.

Abstract:

In this paper, the differences between static instability and dynamic instability are explored with the aid of a nonlinear spring model. It is pointed out that the dynamic instability of structures can not be identified by the pseudo static stiffness criterion. The concept of intrinsic energy of system is then put forward and it is found that the essence of dynamic instability of structures lies in that the intrinsic energy surpasses the energy imported into the structure, where a novel criterion for the identification of dynamic instability of structures is proposed accordingly. The relevant numerical computations indicate that the proposed criterion can analyze and judge the dynamic instability of structures subjected to arbitrary dynamic loadings effectively.