Slepian simulation of plastic displacement distributions for shear frame excited by filtered Gaussian white noise ground motion

Application of the Slepian model process concept to obtain approximate plastic displacement distributions of elasto-plastic shear frame oscillators of one or more degrees of freedom has in previous works been for white noise force excitation acting directly on the first floor mass of the shear frame.

A suitable number of the lower floors has been considered to represent the soil both as a filter of a white noise base rock excitation and as a simplified model for soil structure interaction. In the present paper the Slepian model is applied to obtain plastic displacement distributions for a single story shear frame excited by stationary Gaussian ground motion defined by the output of a Clough-Penzien filter with Gaussian white noise input.

This is equivalent to considering an artificial three story elasto-plastic shear frame with possible yielding solely in the third column connection, and with no force feed back from any of the three masses to masses situated below it. The first mass from the ground is force excited by stationary Gaussian white noise as specified in the Clough-Penzien filter definition.

The study includes comparisons between plastic displacement results for the same three story frame with partial or full feed back from the movement of the top mass to the second and the first mass (top soil layer mass and base rock mass, respectively). Keywords: Clough-Penzien filtered white noise excitation, elasto-plastic shear frame oscillator, plastic displacement distributions, simplified ground structure interaction, Slepian model process simulation