Relevant lessons learned from the earthquakes El Asnam, 10/10/1980 and Zemmouri, 05/21/2003 on the paraseismic prevention in Algeria

Yamina Ait-Meziane,Rania Souici,Farah Lazzali,A Diouri,L Bahi,N Khachani,J Aride,L Ait Brahim,A Nounah,A Boukhari,M Saadi

doi:10.1051/matecconf/201814902040

Abstract

In the field of seismic risk prevention in Algeria, the earthquake of El Asnam, 10/10/1980 is the triggering event and that of Zemmouri 21/05/2003 the accelerating element of the policy already in place. These two major events have been rich in information, as they are among the most studied internationally. The approaches and the development of methods for seismic risk reduction are based largely on feedback. The fundamental goal of seismic risk reduction is to avoid loss of life, which is mainly due to the partial or total collapse of structures. Exploiting lessons learned from past earthquakes is reflected in code requirements for new projects and approaches to vulnerability estimation for existing structures. In this paper, we give a description of the characteristics of the two events. The analysis of pathologies observed and the impact on the Algerian seismic code is discussed.

Highlights

Northern Algeria experienced several seismic events [1]
The two major earthquakes that have occurred in Algeria, El Asnam (1980) Ms=7.3 and Zemmouri (2003) Mw=6.8. accounted 3.500 deaths and 60.000 housing units destroyed for El Asnam region, 2.278 deaths and approximately 15.000 buildings destroyed for Algiers-Boumerdes region that is dense urban zone
The results of field investigations and statistical analyses show that a majority of the damaged buildings were masonry buildings and reinforced concrete frame buildings, in part those built without any consideration to the requirements of the seismic code

Summary

Expertise protocol

Northern Algeria experienced several seismic events [1]. The two major earthquakes that have occurred in Algeria, El Asnam (1980) Ms=7.3 and Zemmouri (2003) Mw=6.8. accounted 3.500 deaths and 60.000 housing units destroyed for El Asnam region, 2.278 deaths and approximately 15.000 buildings destroyed for Algiers-Boumerdes region that is dense urban zone. The results of the damage observed on the buildings during the two events were carried out using the same post seismic expertise by using the damage evaluation sheet related to buildings in the surveyed area (building address, building use, age, number of stories, soils rupture (fault, liquefaction, landslide and settlement), foundation type, resisting system type and observed damage on structural and non structural elements) is collected. Many Dairas and municipalities in Boumerdes and Algiers, are declared disaster zones by the central government decree of May 24, 2003

Characteristics of buildings and observed damage

Algerian Seismic codes

Damage Analysis and discussions

Conclusions