Number of uniform stress cycles equivalent to seismic loading

The concept of equivalent number of uniform stress cycle Neq has been reviewed and several models available in the literature are compared and validated using a large database of earthquake records. Based on results of the analysis new models are developed using multivariate regression analyses. The proposed models are site-dependent relate Neq to seismic parameters that describe the energy and frequency content of the time-history to be converted. A validation of the models is performed showing their accuracy with respect to other available models.