Critical earthquake response of SDOF elastic-perfectly plastic model with viscous damping under double impulse as substitute of near-fault ground motion

Abstract

The double impulse input is introduced as a substitute of the fling-step near-fault ground motion and a closed-form solution of the elastic-plastic response of a structure with viscous damping under the 'critical double impulse' is derived. Since only the free vibration appears under such double impulse, the energy approach plays an important role in the derivation of the closed-form solution of a complicated elastic-plastic response with viscous damping. The quadratic-function approximation for the damping force-deformation relationship is introduced. The validity and accuracy of the proposed theory are investigated through the comparison with the response analysis to the corresponding one-cycle sinusoidal input.