Figure 7. Shear stress-shear displacement diagrams under cyclic loading for ff = 0.75 N/mm2; (a) dry specimens; (b) saturated specimens.
grains against other rock-forming minerals could provide the stick-slip on the surface of granite. When an analysis of the normal displacement-shear displacement diagrams is carried out, it is possible to observe a more visible tendency for compaction associated to the wearing of the joint surface.
From the normal-shear displacement diagrams, it is possible to conclude that the values of dilation/compaction are not greater than ±0.06 mm, which shows good agreement with the values reported by Lourengo & Ramos (2004) for dilation obtained on sandstone smooth dry joints and with the results pointed out by Homand et al. (2001) for hammered granitic joints. In both cases, the degradation mechanism is dominant over the phenomenon of dilatancy. Therefore, it is reasonable to assume that this type of smooth rock joints is non-dilatant. This result is also enlarged to the shear behavior of saturated specimens. In fact, it is well known that the dilatant behavior
Was this article helpful?