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Lebanon is characterized by strong but rare earthquakes. Beirut's important urban density results in a high level of human vulnerability. A questionnaire survey performed on a sample of 176 people allows better understanding of the individual vulnerability of residents facing earthquakes. The survey questions the perceptions and the knowledge about seismic hazards, the behaviors in case of an earthquake, and the protection strategies. The results show a good perception of the seismic threat but dispersed knowledge. The residents know how efficient earthquake-resistant construction is, expect more information but remain skeptical about institutions. Among the variables explaining this, education has a key role, unlike classical factors such as gender, the presence of children, or the lessons drawn from past experience. A synthetic index built from the answers to the questionnaire confirms the role of education. [ABSTRACT FROM AUTHOR]

The city of Oran is exposed to a significant seismic hazard, as almost all the northern Algeria territory, where numerous casualties and severe damage occurred in the last decades due to several moderate to large earthquakes. A mitigation policy should include the establishment of priorities to reduce the vulnerability of existing buildings based on the knowledge of the actual urban fabrics. The complexity of vulnerability assessment requires a gradual approach from the urban scale to the building scale. The study reported in this paper corresponds to the first step of such an approach, i.e., a preliminary study of the seismic vulnerability and expected damage within an urban district of the city of Oran, based on a non-dedicated data base from a building survey previously performed for other purposes. The main goals of this study are twofold: (1) an assessment of the degree of uncertainty and robustness of such results through a comparison of the results derived from different urban vulnerability methods (GNDT 2; RISK-UE LM1; and VULNERALP 2.0) and (2) an assessment of the actual level of seismic risk in the city of Oran. Cross-method comparisons and correlations highlight a satisfactory agreement between mean damage estimates at the urban scale, despite significant scattering at the single building scale, and uncertainty levels which vary significantly from one method to the other. For a given scenario, the three methods provide damage estimates lying within half an EMS damage degree of one another, with some systematic positive bias for VULNERALP and negative bias for RISK-UE LM1, especially for masonry buildings. The expected mean damage is very important for intensities 9 and 10, with an average damage grade around 3-4 for intensity 9 and 4-5 for intensity 10. The spatial distribution of damage systematically exhibits larger values in the northern, older, commercial area, than in the southern, more recent and more residential area, in relation to the building typology and the existence of several aggravating factors. Some areas of higher vulnerability / damage can be distinguished, which should receive particular attention for retrofitting priorities or urban planning decisions, also taking into account their cultural heritage value. [ABSTRACT FROM AUTHOR]