Cumulative Damage of Structures Subjected to Response Spectrum Consistent Random Processes

Citation

Jeong, Garrett Duane (1985) Cumulative Damage of Structures Subjected to Response Spectrum Consistent Random Processes. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/97b3-2427. https://resolver.caltech.edu/CaltechTHESIS:04052019-121036771

Abstract

A theoretical analysis of the effect of duration on the damage of structures subjected to earthquakes is presented. Earthquake excitation is modeled as a nonstationary random process. Estimates of the first-passage probability of a simple oscillator are employed to choose modulated Gaussian random processes consistent with a prescribed response spectrum. The response spectrum is assumed to be specified independent of the duration. Expressions for the mean damage of a structure are derived using an approach similar to the Miner-Palmgren rule for failure caused by cyclic loads. The expected damage expressions are then evaluated for a structure subjected to modulated Gaussian random processes of varying duration.

Two types of structures are examined: a steel structure and a reinforced concrete structure. Results are presented for systems with constant linear stiffness and a particular form of softening behavior. The nonlinearity of the softening system is accounted for by statistical linearization. The level of expected damage is found to be a strong function of both the duration of the excitation and the ductility of the response.

Thesis Files