Evaluating Seismic Performance of Existing School Buildings in Gaza Strip

Abstract

This research work introduces a new approach for assessment of existing school buildings in Gaza Strip against seismic hazards. The proposed approach is simple, straightforward and based on studies that deal with seismic requirements for school building in terms of resisting expected seismic action. Although it can be implemented by a small team from various technical construction backgrounds, it complies with the latest developments in seismic evaluation standards. The approach has been developed based on EMS-98 scale and previous local/regional related studies. The proposed approach depends mainly on rapid survey of architectural and structural elements of existing concrete buildings that should satisfy minimum seismic requirements. The results led to classifying buildings to vulnerability classes based on EMS-98 scale and damage degree. The research covers evaluating three samples of the dominant structural systems of school buildings in Gaza Strip using ASCE03-31 and carrying out a comparative study with the results obtained from the proposed approach. Studying all existing school buildings in Gaza Strip (420 buildings) would consume a lot of time and effort. Therefore, the researcher suggests using Arc GIS software to select representative school buildings for application of the new approach. After verifying the validity of using the proposed approach by applying it on more than 64 case studies based on EMS-98, the results showed that 70% of surveyed schools are Classified as seismically vulnerable (50% class “B”, 20% class” A”) . The major educational governorates of Gaza Strip might expect full or partial damages (31 % of Gaza, 34% for Middle Area, 37.5% for Rafah, 27% for KhanYounis , 25% for North Gaza) at low damage degree (damage three) defined by EMS-98 scale. Applying ASCE 03/31 standard on selected structural system of existing school in Gaza Strip, show that these systems are vulnerable to “captive column” phenomena, which reflect low performance against seismic action. The proposed approach results have been verified using the ‘probability matrix damage’ equation and showed convergence in the results. Different scenarios have been prepared for the expected damage based on earthquake damages defined in EMS-98. The results are expected to shed the light on the importance of carrying out similar studies on public buildings as well as essential facilities in Gaza Strip.