Comprehensive data for stress intensity factor and critical crack length in chevron notched semi-circular bend specimen subjected to tensile type fracture mode

Abstract

Semi-circular bend (SCB) specimen is one of the test specimens for determining the fracture toughness of brittle and quasi brittle materials such as rocks. Two types of initial notch geometries can be introduced in this specimen: straight notch and chevron notch. To determine the fracture toughness of materials by means of these two SCB configurations, the dimensionless stress intensity factor is a key fundamental parameter that is determined by theoretical or numerical methods. This paper provides comprehensive data for determining the normalized critical crack length of SCB specimen with chevron notch and under pure mode I loading. The minimum dimensionless stress intensity factor and the normalized critical crack length for the chevron notched SCB specimens are presented based on extensive finite element analyses for a wide range of geometric and loading parameters, including SCB thickness, initial notch length, chevron angle, and bottom loading support distance. For evaluating the accuracy, the results obtained from FE analysis are compared with those obtained from a semi-analytical procedure, i.e., slice synthesis method. The comparison shows quite good agreement that confirms the accuracy of FE results.