Dynamic Stability of Damage-Prone Inelastic Structural Systems

摘要

The behavior of a simple mechanical system, experiencing large deformations and inelastic material responsewith damage. is presented. Because the differential equations that describe the motion are highly nonlinear andcoupled for the multi-degree-of-freedom system, a numerical procedure was employed to determine the response.While most engineering approaches to the design of such systems utilize a static approach, results from this researchindicate that static analyses cannot effectively predict the behavior of a dynamic, damage-prone system.Most importantly, the rate of damage accumulation will have the greatest impact on the stability properties of thesystem. In fact, for certain load cases, a system that accrues more damage may be less prone to instability than asystem that suffers little damage. For this research, it was assumed that damage caused a reduction in the stiffnesssuch that the structure experienced cyclic softening with increased cycles of loading. Application of the results toseismic-resistant design was considered.