Standards for Fracture Toughness Testing of Rock and Manufactured Ceramics: What Can We Learn for Concrete?

Abstract

AbstractThis paper presents a review of the American Society for Testing and Materials (ASTM) and the International Society for Rock Mechanics (ISRM) standards for determining the plane-strain fracture toughness of cemented carbides and rocks, respectively, with an eye toward applicability to concrete. The evolution of the chevron-notched test specimen used in these standards is briefly reviewed. A discussion of a particular chevron-notched configuration, the short rod test specimen, and associated test methods follows. The ASTM and ISRM standards are then described. The paper evaluates the potential for learning from, modifying, or adapting these standards for use on a standard fracture toughness test for concrete. The potential advantages and disadvantages of using the short rod geometry and testing methods on concrete are discussed, taking into account fracture response, shape, volume, preparation, precracking, symmetry, and subsize specimen effects. Preliminary research into the applicability of the short rod geometry and testing procedures on concrete is discussed.