Fracture toughness of different types of granite

摘要: The optimisation of processes such as drilling, cutting, grinding or polishing, demands understanding the in uence material related properties overall process [1]. For example, fracture mechanisms involved removal (and their dependence on microand macro-defects inevitably present) plays a decisive role practical rock engineering and fragmentation (as those referred above). As result, signi®cant number research studies is currently being undertaken order to further clarify certain parameters (such toughness stone material) mechanisms, well develop accurate methods for determination [2±4]. Fracture can be de®ned measure ability resist growth preexisting crack aw under stress, has been extensively used design safe structures. Using linear elastic mechanics (LEFM) it possible establish relationship between strength cracked structure material's toughness, size, geometry location. are therefore necessary failure analysis. Most these permit evaluation lower bound i.e. planestrain which extension resistance conditions crack-tip plane strain. In brittle materials, pure mode I loading (KIc) with critical value strain energy release rate (also termed force), Gc, according expression: KIc ˆ  EGc …1y u2† s