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Dynamic Stability of Damage-Prone Inelastic Structural Systems.
Williamson, E. B.; Hjelmstad, K. D.
National Science Foundation, Arlington, VA., cMay 1996, 172 p.
Identifying Number(s)
The behavior of a simple mechanical system, experiencing large deformations and inelastic material response with damage, is presented. Because the differential equations that describe the motion are highly nonlinear and coupled for the multi-degree-of-freedom system, a numerical procedure was employed to determine the response. While most engineering approaches to the design as such systems utilize a static approach, results from this research indicate 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 the system. In fact, for certain load cases, a system that accrues more damage may be less prone to instability than a system that suffers little damage. For this research, it was assumed that damage caused a reduction in the stiffness such that the structure experienced cyclic softening with increased cycles of loading. Application of the results to seismic-resistant design was considered.
; Damping; Earthquake engineering; Seismic design; Numerical analysis; Stability; Buckling; Nonlinear systems; Dynamic structural analysis