Rapid Application of the RISK-UE LM2 Method for the Seismic Vulnerability Analysis of the Algerian Masonry Buildings

ABSTRACT

The building stock in most historical urban areas in Algeria consists of old masonry buildings which are characterized by the rather high vulnerability. In that respect, to reduce the seismic risk there is a requirement for strategic urban planning and urban management policies. This paper focuses on the assessment of the seismic vulnerability using the RISK-UE methodology, namely the mechanical method LM2, which is adopted and applied to fit the Algerian urban features. In order to implement the RISK-UE LM2 methodology, an old urban center in Annaba city is chosen as a pilot area. Almost, the majority of the structures are unreinforced masonry buildings. In total 226 buildings were assessed, which are typical not only for this region but can be found in many other medium-sized Algerian urban environments. Three scenarios that take into account various values of the peak ground accelerations (PGA) are elaborated. Two scenarios use PGAs issued from an existing probabilistic seismic hazard analysis (PSHA) of Annaba city for 100 and 475 return periods. The third PGA for the last scenario is taken from the Algerian seismic code (RPA99/2003). In order to highlight the degree of vulnerability and risk of the studied masonry buildings, a comparison between the three seismic scenarios is presented in detail for each building’s typology. The obtained seismic vulnerability outcomes offer a great prospect to provide recommendations for making correct decisions to reduce the seismic risk and conduct adequate emergency planning in Algerian urban areas.

KEYWORDS:

• Algeria
• large scale analysis
• LM2 method
• masonry buildings
• peak ground acceleration
• performance point
• RISK-UE approach
• seismic scenarios

Acknowledgments

The authors would like to thank both the technical organism in charge of the Technical Control of Construction in Annaba city (CTC) and the Direction of Urban planning and Construction of Habitation (DUCH) for providing the technical files on the buildings’ diagnoses.

Disclosure statement

No potential conflict of interest was reported by the authors.