Abstract: This technical note explores the physical and mathematical basis for the drift demand spectrum proposed in the 1990's by Iwan, and reveals several unexpected features of the original mathematical formulation. It is shown ...

Abstract: Suspension bridges in the Central and Eastern United States (CEUS) were built before recent advances in earthquake engineering, and may be susceptible to seismic ground motions. A retrofit strategy is proposed in which ...

Abstract: A step-by-step procedure for linear analysis of building structures with rigid floor beams is developed and presented. The method outputs the maximum story drift envelope, and consists of a series of explicit formulas that ...