Soon after the 21 May 2003 Zemmouri (Algeria) earthquake that had stricken mainly Boumerdes and Algiers prefectures, inventory investigations were conducted on the existing constructions and facilities in order to evaluate losses and damages that affected these areas. This paper presents observations and analyses concerning a locality judged to be typical and might be considered as a case for the entire affected prefectures. A recently urbanized small zone of approximately 4 km
2 located in Algiers Prefecture and near the border of Boumerdes Prefecture was investigated in detail. A total of 725 buildings were evaluated. Analysis of the collected data showed that damage was randomly distributed in the area. This result strengthens the assumption of low-quality materials and inadequate design, in relation to other assumptions, such as the effect of soil conditions. Reinforced concrete constructions were the most affected among the various other types, with approximately 18% of constructions of this type having suffered moderate to heavy damage. Data analyses showed that the most affected constructions were those in the range from 5 to 6 stories while buildings with only one story did not suffer any damage. Typical observed damages were, for the most part due to poor longitudinal and/or transversal reinforcements in the columns, very poor concrete quality, lack of shear reinforcements at beamcolumn joints, soft stories, pounding and the formation of short columns. Restoration of facilities and retrofitting practice on damaged buildings are reviewed in some cases.
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