Estimation of Joint Roughness Coefficient from Three-Dimensional Discontinuity Surface

Excerpt

This paper proposes a new method to account for the variation of roughness profiles in three-dimensional space in rock mass. Shear strength and hydro-mechanical behavior of discontinuities in rock masses are heavily influenced by the joint roughness properties (Tse and Cruden 1979; Maerz and Franklin 1990), and thus it must be defined accurately to avoid design errors. Pioneering work on this area was done by Barton who introduced the joint roughness coefficient (JRC) to define discontinuity roughness (Barton 1973). Since then, JRC has been widely used in rock engineering. It is well understood that JRC has directional dependency with which shear strength and hydro-mechanical properties vary significantly. Therefore, many researchers developed some models to estimate JRC accurately in two dimensions (e.g., Tse and Cruden 1979; Maerz and Franklin 1990; Kulatilake et al. 2006; Tatone and Grasselli 2010), which obviously lacks accounting the variation of roughness in three-dimensional (3D) surface. …