DRILLING DATA LOGGING ON THE NEW TGV RAILWAY TO THE MEDITERRANEAN SEA

New techniques become available continually to geotechnical engineers, such as drilling data logging in real time. Principles and capabilities of the technique are first presented and then two typical examples of use are proposed which are taken on the new very high speed railway line between Valence and Marseilles. For the first one, the target was to more closely delineate layers interface and continuity of tertiary formation; for the second, to exactly detect the boundaries of a highly fractured zone in a sound rock. Combined parameters appear very helpful.