ABSTRACT
This paper aims to compare two different approaches for fracture assessment on rocks containing U-shaped notches and subjected to Mode I loading conditions. First, the Strain Energy Density (SED) criterion has been considered, which is based on an energetic continuum approach for rock fracture predictions. Likewise, the Theory of the Critical Distances (TCD) has also been applied, which can be considered as a local failure criterion based on the stress field near the notch tip. Both methods properly describe the rock fracture behaviour and provide relatively accurate and reliable estimations. Thus, the rock fracture predictions provided by these two methods have been analysed and compared in this paper, trying to focus on the particularities of each one. The research is based on the results obtained from an exhaustive experimental program comprising 78 fracture specimens of a Moleano Limestone. This program includes 12 Brasilian tests, 12 simple compression tests and 54 parallelepiped specimens tested in 4-point bending conditions with 8 different notch radii varying from 0.15 mm up to 15 mm in order to consider the possible notch effects.
