关键词: 非线性动力, 动力屈曲, 跳跃屈曲, 浅拱

Abstract:

This paper deals with the snap-through buckling of a shallow elastic arch under dropping impacts by means of the nonlinear dynamic method. In the investigation, a nonlinear dynamic equilibrium equation is deduced based on the Hamilton principle and is then analyzed using both the single-mode and the double-mode methods. Then, the governing equation of structure responses is obtained via Galerkin＇s approach. Moreover, the charactcristics of equilibrium points of the system are discussed and the stability of system attracters and their attraction domains is analyzed. Numerical results show that the double-mode method is more accurate than the single-mode one. The single-mode method may give incorrect critical buckling conditions and dynamic responses in some conditions. In addition, the initial shape of the shallow arch greatly affects the critical conditions of snap-through buckling, and that higher arch may possess greater buckling bearing capacity.

Key words: nonlinear dynamics, dynamic buckling, snap-through buckling, shallow arch