GENERATION OF ENERGY SPECTRUMS USING A SET OF PERUVIAN SEISMIC RECORDS OF ACCELERATIONS

Based on the energy balance equation developed by Housner and Akiyama [1], and using seismic accelerations records measured in Peru a set of energy spectra was generated. These energy spectra allowed to verify that the energy demanded by a severe seismic event is less than the energy dissipation capacity of a structure, which increases the probability of meeting the objectives of structural performance and satisfying with the expected damage control. The energy spectra were generated based on the non-linear seismic response for discrete systems of one degree of freedom, considering that the relevant response is mainly determined by the energy dissipation capacity and, consequently, by the change in the period of vibration. Therefore, to carry out this study, a set of seismic acceleration records and the methodology proposed for Avendaño and Fernandez-Davila [2] were taken as a basis. The input data consisted of an amount of 68 pairs of seismic acceleration records and were classified and filtered according to Peruvian seismic code E-030 [3], and they are following: Hard Rock (51), Rocky or Rigid Soils (10), Intermediate Soils (9). Besides, from the lateral displacement curves, it was observed that the seismic performance and the response of buildings subjected to severe seismic events were strongly influenced by the geotechnical characteristics in situ and the seismic ground motions. The main conclusions were: i) Show the shape and the trend of the inelastic spectrum made in base of Peruvian seismic records, ii) Show the importance of the ductility demanded in the application of the methodology proposed herein, since this is a parameter that depend mainly of the lateral resistance and lateral displacement relationship, and therefore, this is a key factor to link the expected nonlinear behavior and the structural response before a large number of seismic events, iii) it was verified that the input energy spectra and the hysterical energy calculation reveal and apply relevant information, such as the total frequency content and duration of the earthquake which are not considered by the typical pseudo-acceleration response spectrum.