Characterization of shear behavior of discontinuities of brioverian schist
Résumé
In order to better characterize brioverian schist of Rennes Bassin (Brittanny) the mechanical behavior of the discontinuities (schistosity and/or stratification planes) extracted from different excavation sites was tested. A Casagrande shear box, rather adapted to characterize soils, was used which was a challenge due to the brittleness and the unmoldability of the material. Yet, the results demonstrate that this type of equipment, much more economical than a classic rock shear test installation, is adapted to characterize Hard Soil or Soft Rock (HSSR) such as brioverian schist. The experiments highlight the influence of the petrography of the specimen on the friction angle. Moreover, tests realized under two different water condition (dry and after immersing the joint) show the differentiated influence of the presence of water according to the nature of the rock. © 2018 Taylor and Francis Group, London, UK.