Earthquake Response Statistics of Nonlinear Systems

A stationary, Gaussian random process, having a prescribed nonuniform power spectral density function determined by a special simulation procedure which realizes the local site geology is used to analyze the response statistics of nonlinear yield type structures subjected to earthquake excitations. The structures investigated are single-mode oscillators covering long and short periods, high and low viscous dampings, and having history-dependent and -independent interanal energy dissipation mechanisms as represented respectively by stiffness degrading and ordinary elasto-plastic models. Emphasis of the analysis is placed on the probability distribution of the single highest displacement (SHD) response of structures and the accumulation of damages caused by consecutive earthquake loadings.