3D geostructural modeling of rock faces Application to the SNCF earth works

摘要

Within the framework of a research project carried out in partnership with the Universities of Strasbourg and Savoy, ATT~1 and OTH ~2 divisions of the department "Study of Lines" of the SNCF Management of Engineering, carry out a study on the 3D geostructural modeling of rock faces. This project aims at a better knowledge of the rock cuttings along the national rail network. The rock faces diagnosis is a follow-up and check operation of the earth works, that requires a structural analysis (statement of various discontinuities of the rock mass and data processing). At the moment, this tiresome expert work is generally completed in a simplified way based on the specialist experiment. Limited on a specific part of the work (often the most fractured zone), the analysis remains empirical. Filling these gaps, the combined use of dense three-dimensional measurements techniques (photogrammetric and/or lasergrammetric) makes it possible to obtain a relatively exhaustive structural statement. The diagnosis is thus made reliable and the recommendations are optimized with the unfavourable sectors. The risk analysis can be targeted on the potential disorders zones and not on the whole studied sector. This article deals with the principal modeling techniques currently used as well as the results we obtained at the present state of the project.