Computation of Inelastic Response Spectra

A method for the computation of response spectra for elastoplastic and bilinear hysteretic systems subjected to strong‐motion earthquake records is described and compared to Newmark's method. The technique provides the exact solution to the governing equations of motion assuming that the ground acceleration varies linearly between successive points, A fractional time stepping scheme is incorporated to detect yielding and unloading accurately. The procedure permits the computation of dynamic response in an efficient, arithmetical manner, and provides a two‐ to three‐fold savings in computation time compared to Newmark's method.