Evolution of Joint Roughness Degradation from Cyclic Loading and Its Effect on the Elastic Wave Velocity

Excerpt

The application of stress to the rock joint has a significant impact on morphological and mechanical properties of the joint. In particular, the evolution of the joint condition is dramatic on the surface of the weathered rock whose material integrity is altered in a manner similar to the rock joint behavior from weathering effects (Resende et al. 2010). As indicated in Kabeya and Legge (1997), a significant change in the weathered rock joint surface can be induced by the modification of grain properties of the joint surface. The grain size distribution has been found to be strongly correlated with the shear behavior and the joint roughness coefficient (JRC). The open joint or gouge dominates in weathered joints of the rock mass structure, thereby providing access for weathering agents to increase the failure likelihood from a slickenside (Woo et al. 2010). This granular disintegration leads to surface flakes to transform the joint aperture into a wider opening. …