Earthquake Damage Assessment Using GIS

Author: Aymen Aly Solyman
Organization: Regional Observation Center

129 SHOUBRA STREET - CAIRO - EGYPT
Cairo, 129 Shoubra street - Cairo - E

Phone: 00202-4305804
Fax: 00202-2673008
asolyman@idsc.gov.eg

On Monday, October 12, 1992, at 13:09:56.3 UT, Cairo and northeastern Egypt experienced a rare, damaging earthquake. The earthquake, which measured (Mb = 5.9), was centered near the village of Dahshure, about 20 km south of Cairo. This earthquake caused extensive nonstructural and moderate structural damage. According to official sources, the City of Cairo and the neighboring towns suffered 556 deaths and 6,500 injuries as a result of this earthquake. About 350 building structures collapsed (mainly old reinforced masonry buildings) and 8,000 were damaged. An estimated 3,500 adobe-type buildings in the surrounding villages also collapsed. It was estimated that monetary losses directly attributable to this earthquake were about $300 million. Using geographic information systems to assess the damage after the earthquake allowed integration of different types of data layers. Most of these data layers had geographic distribution.

A GIS was developed to evaluate the damage of buildings in greater Cairo and to review the performance of structures during the October earthquake. This system was developed by integrating spatial data and attribute data. The spatial data consisted of a number of data layers that had geographic distribution such as the administrative boundaries of greater Cairo, soil type classification layer, peak ground acceleration layer, intensity distribution layer, groundwater levels layer, and location of the epicenter of the earthquake layer. The attribute data consisted of information obtained from the investigation reports after the earthquake. A detailed spatial database for Al-Haram district was also established to enable more understanding of the different structures in hazardous areas.