Méthode H/V en géotechnique. Application à un modèle bicouche

Abstract

H/V method in geotechnical engineering. Application to a two layers model AbstractThe implementation of the Eurocodes which have the status of European standards for the constructive rules for buildings and civil engineering, led to the writing or to the revision of the national standards. Since 2010, the standard EN 1998 or Eurocode 8 engendered a revision of the French regulations in seismic hazard mapping as well as the values of the parameters occurring in the design of normal and special seismic risk projects. The shear wave velocity values V5 is the more important criteria for ground type definition and so for the elastic spectrum. Building project needs representative ground type definition based on investigations. That's the reason why the horizontal to vertical spectral ratio seismic ambient noise method was tested to estimate the ground fundamental period T0 in a geotechnical purpose, by virtue of its ease of use. The method exists since about twenty years and was concerned with a significant development these last years at instigation of the seismological research SESAME project in Europe. Some of the SESAME conclusions were used as theoretical support to this article. In conditions of restrictive use, as for two soil layers models with a net acoustic impedance contrast it is possible to pre-characterize the ground type in the sense of the standard EN 1998.