Nuclear logging in the Laboratoires des Ponts et Chaussees

Over the past fifteen years, the laboratories des Ponts et Chaussees have developed, in the context of research programmes, nuclear logging for civil engineering applications. After briefly reviewing the physical principles of nuclear logging, the authors describe the techniques involved. The calibration facility installed in the Laboratoire Regional des Ponts et Chaussees de l'Ouest Parisien (near Paris) is used to take into account the effects of: the chemical composition and humidity of material, the diameter of the borehole. The authors give different examples of the application of nuclear logging to study of large structures, roads and rail infrastructures and various development projects, which sometimes involve public safety. In conclusion, reference is made to the financial advantage and the yield of these nuclear logging in general reconnaissance work or detailed surveys, by comparison with traditional methods. (authors). 10 figs., 1 tab., 11 refs