Two Peaks Response Spectra (2PRS) for Subduction Earthquakes Considering Soil and Source Effects

Abstract eng:
Two peaks design response spectra (2PRS) for Chilean seismic code are proposed considering soil effects and seismic source effects. These spectra consider the source effects of interplate thrust and intraplate of intermediate depth earthquakes that are characteristic of Chilean subduction seismicity. These types of earthquakes present different characteristic periods of seismic source. The proposed spectra are the envelope of one of the source seismic spectra of the two considered types of earthquakes and one soil spectra. In the soil spectra the effect of soil damping is introduced explicitly, this condition produces higher decay than the actual one for the high periods. The spectra is obtained using the accelerograms from epicenter zones of large magnitude earthquakes close to the design magnitude, avoiding to mix with small amplitude accelerograms corresponding to earthquakes of small and moderate magnitudes, because the energy in seismic source periods is observed only in epicenter accelerograms of large earthquakes. The periods and dampings for the soil and the source seismic periods are proposed for different types of soil, according to Vs dynamic classification, for spectra of Chilean subduction earthquakes. The proposed designs 2 PRS consider the subduction due to Nazca plate, but it can be expanded to other subduction or non subduction zones.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket