6. Conclusion

The work carried out by the technical departments of the French Ministry of Ecology, Sustainable Development and Energy (notably Sétra and CETE Méditerranée, now part of Cerema) has led to the definition of a methodological framework for addressing the issue of seismic risk on existing bridges.

The approach we have developed consists in proceeding in successive stages, corresponding to different scales of analysis and associated with different levels of refinement:

• on a route or route section scale, by prioritizing structures so as to concentrate efforts on the most "at risk" bridges, i.e. those with a high strategic stakes, high exposure to the hazard (moderate to high seismicity or low seismicity but associated with unfavorable site conditions, etc.) and high presumed vulnerability;

• ...