Research Abstract:
The 11 February 2004 earthquake (ML 5.2) with an epicenter in the
northeastern part of the Dead Sea basin (at latitude 31.679 N,
longitudes 35.585 E with a focal depth of 17 km) caused slight damage to
several regions in the West Bank, Palestine. The earthquake was felt in
the Palestinian cities: Jericho, Hebron, Nablus, Ramallah, Bethlehem
and Jerusalem but no life loss was reported. Moreover, few smaller
earthquakes followed the Earthquake of 11 February 2004 at different
locations and times of the same year 2004: 7 July ML 4.8 ( Lat 31.97
Long 35.55), 20 July ML 3.6 (32.46, 35.25), 2 December ML 2.8 (32.25,
35.37). They mainly felt in the northern part of West Bank especially in
Nablus City, although they are not closed to Nablus but because of some
site effects factors (geological formations, structures etc.). Based on
postearthquake investigations, many reinforced concrete buildings in
Palestine suffered slight non-structural damages (damage grade 1
according to European Macro seismic scale 1998 “EMS- 1998”), such as
hair-line cracks in very few walls, specially over frame members or in
walls at the base and fine cracks in partition walls. Three old schools
suffered moderate structural
damages and substantial non-structural damages (damage grade 3). The
Earthquake affected also many old masonry buildings in the Palestinian
old cities (Jerusalem, Nablus, Hebron, Bethlehem, ….etc), in Nablus city
few historical buildings have been affected with damages between grade 2
to grade 4. The damages that had been occurred had usually been at zone
of pre-existing weakness. In the light of the post-earthquake
investigations the effected masonry and old masonry buildings suffered
with many kinds of damages, such as: crack patterns in masonry pillars,
slippage between the block, corner detachment, a flat vault’s collapse,
detachment between few
perpendicular walls (in a corner) and crushing in masonry pillars.