Mixed-Mode Fracture Characterization of Rock using Strain Energy Release Rate Technique

Fracture mechanics can be applied to many engineering fields including civil and mining engineering, where drilling, excavation, explosion and cutting of rock are related to the strength, stability and fracture of rock materials and structures. Obviously the principles, methods and techniques of fracture mechanics can play an important role in the analysis, design and construction or production of many rock engineering projects. In this study, mixed- mode fracture of rock through numerical and experimental methods using strain energy release rate technique have been investigated. A modified version of the Arcan specimen was made for the mixed- mode fracture test of rock specimens, which allows mode-I, mode-II, and almost any combination of mode-I and mode-II loading to be tested with the same test specimen configuration. Therefore, disadvantages presented in the previous mixed-mode toughness test methods can be avoided. The strain energy release rate technique is useful for studying the mixed-mode and complicated loading conditions and especially for anisotropic materials like rock. In the present study, fracture behaviors of rock using strain energy release rate technique were investigated through experimental and numerical analysis.