Characterization of Shear Behaviour of Rock Joints Using Fractals

摘要

Among the diverse approaches available for the representation of shear strength of jointed rock masses, that using JRC is noteworthy. But the subjectivity associated with the determination of JRC has led to the search for a more representative parameter. During the past decade fractal dimension has emerged as a possible alternative. In this study on use of fractals there are three stages. First deals with studies on plaster of paris model joints of predetermined and known JRC and correlating their roughnesses with ultrasonic wave velocities. Second, these are then used to predict roughnesses of jointed rock cores. The roughness is expressed in terms of both JRC and Fractal Dimension. The predictions are validated by direct measurement of the roughnesses with the help of a digital Perthometer. Third, these are extended to evolve an alternative equation for shear strength of jointed rock. The results are compared with other published data.