Multi-scale study on the deformation and fracture evolution of clay rock sample subjected to desiccation

摘要

The aim of this paper is to compare and discuss the values of strains and crack apertures associated with desiccation cracks measured in Tournemire clay rock at different scales (micrometer to decimeter). Experimental investigations in the laboratory were conducted on one clay rock sample subjected to a desiccation process. Two faces with dimensions of 20 x 20 mm(2) (i.e., macroscopic scale) and 5.1 x 4.1 mm(2) (i.e., mesoscopic scale) were analyzed. The induced hydric strains and desiccation cracking were monitored by digital image correlation combined with a new algorithm (H-DIC). The results were compared with the data of Hedan et al. (2014) at the gallery scale (decimeter) and those of Wang et al. (2013) at the microscopic scale (micrometer).