Ricerc@Sapienza

A widespread approach for the prediction of the structural response as function of the ground motion intensity is based on the Cloud Analysis: once a set of points representing the engineering demand parameter (EDP) values is obtained as function of the selected seismic intensity measure (IM) for a collection of unscaled earthquake records, a regression analysis is performed by assuming a specific functional form to correlate these variables.

The equivalent linearization is a well-known simplified approach for estimating the maximum absolute displacement of inelastic systems, being widely adopted in many technical codes and guidelines. In this regard, the present paper addresses the use of the equivalent linearization to estimate the peak displacement of bilinear oscillators with known displacement ductility subjected to near-fault pulse-like earthquakes. An extensive numerical investigation is initially performed in order to evaluate the accuracy of a recent equivalent viscous damping formulation.

The present work illustrates the results obtained from the application of the Variational Mode Decomposition technique for processing near-fault pulse-like seismic signals. This method has been adopted to analyze a database of fault-normal horizontal impulsive seismic signal components and proved able to extract the mode that embeds the dominant pulse, which is approximated by means of well-known numerical pulse-like waveforms. Pulse period values estimated according to this technique are in good agreement with the ones obtained by means of existing methods.