Chapter 12 - Recent applications of NDSHA: seismic input for high rise buildings in Egypt’s New Administrative Capital

Abstract

Seismic design for high-rise buildings is challenging particularly in areas of moderate seismic activity where acceleration records of past events are not available and the long period effect of distant earthquakes needs to be incorporated. The New Administrative Capital of Egypt is built in an area of low-to-moderate seismicity, with a known active fault system and it is historically proved that strong earthquakes in the Mediterranean have damaging effects on Northern Egypt. In this work, we have utilized the neo-deterministic seismic hazard approach a modern approach that can incorporate all information, from geology, tectonics, geodesy, rupture process, and seismicity, to produce site-specific seismic hazard assessment. Both, local and distant earthquakes, have been incorporated to produce a synthetic seismogram (displacement, velocity, and acceleration) and spectral accelerations to be used by the structural designers. The response spectra equivalent to the peak values of acceleration (PGA), at 50th, 84th, and 95th percentiles, are obtained by selecting at each period of the spectrum the scenario that may contribute to the level of hazard at each site. The results obtained estimated the PGA median value (50th percentile) is about 0.16 g, which is comparable to 0.15 g PGA of the Egyptian building code for zone II where the site is located. The 84th and 95th percentile of seismic response spectra are also calculated to provide further input for the performance-based design. The PGA value for 84th and 95th percentile equals 0.23 and 0.28 g, respectively.