Currently, two main families of methods exist to assess the vulnerability of buildings: empirical methods, for large scale applications only, are based on visual screening survey and observed damages; analytical methods, either used at large scale or for a particular building are based on simple modeling of the seismic behaviour of structures. Calvi (ISET, Vol. 43 (3), 2006) proposes an excellent review of the existing methods. In the frame of the VulneRAlp project, a simple empirical method, based on Italian methods, was proposed for France.

Research axes

In order to better reproduce the seismic response of existing structures, for which the characteristic are poorly known, my main research axis is to determine what could bring vibration recordings to vulnerability assessments.

Unreinforced masonry structures are of uppermost importance for countries like France and Switzerland since they constitute the greatest part of existing buildings. However, they can and deserve not to be all retrofitted. A better estimation of their seismic vulnerability is needed.

Another issue is the estimation of the seismic demand for inelastic structures: the equal displacement rule ensures that the displacement of an elastic and a plastic structure of the same elastic frequency will be the same. This is verified for long-period structures but this underestimates the displacement demand for stiff structures, i.e. a vast majority of existing structures, e.g. masonry structures.

Simple relationships to estimate the period of structures are also necessary for design and assessment.