الفهرس 
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Abstract
Although the area of Cairo is not a place of high seismic hazard compared to other
parts in Egypt (e.g., Northern Red Sea, Gulf of Suez, and Gulf of Aqaba), it may be a
place of high seismic risk or high probability of seismic losses. This is may be
attributed to the high population density and the presence of many cultural, economic,
and political centers in the city of Cairo. In addition, most of the buildings and
lifelines do not follow anti-earthquake design codes, especially those found in some
localized rural communities. It is well known that near-surface geological conditions
strongly influence earthquake ground motion at a particular site. The objective of this
work is to analyze the influence of local geology in the southern part of the city of
Cairo on earthquake ground motion and preliminary estimation of site classification
scheme and strong motion modeling for the purposes of seismic design for this
heavily populated area.
Boreholes data, which are available from 36 sites in the study area, were used to
investigate the lateral and vertical changes of the characteristics of the subsurface
layers. A shallow seismic refraction survey was carried out at 11 sites in the study
area in order to estimate seismic velocities (Vp and Vs) and to detect the shallow
ground model. Ambient vibrations were recorded at three arrays in the investigated
area in order to obtain the shear-wave velocity profile for both shallow and deep
sedimentary layers. The frequency-wavenumber (f-k) method was used to derive the
dispersion curves from the raw signals. The resulted dispersion curves were inverted
using the neighbourhood algorithm to obtain the Vs and Vp velocity profiles at the
measured sites. The Vs and Vp obtained from seismic refraction and ambient
vibrations array were used in determination of the geotechnical parameters and
dynamic characteristics for the shallow sedimentary layers, which are of great interest
in civil engineering applications.
Site classification for the investigated area was performed using the scheme accepted
in the European building code (Eurocode 8), which is based on the average shearwave
velocity for the upper 30 meters of the soil column (VS, 30), as well as the value
of standard penetration test NSPT (available from boreholes data). Also, the
information on groundwater level, which is available from boreholes data, was used to
Abstract