This paper discusses how the shape and preparation of the notch affect crack propagation in ceramic materials with heterogeneous microstructures and, as a result, the maximum load and fracture energy when these materials are subjected to loads using the wedge splitting test. Mortars were prepared with Portland cement, sand and water, which were mixed, molded, and cured at 25 ºC for seven days. After curing, the samples were dried at 55 ºC for 48 h. Two mortar compositions were prepared with proportions of sand:cement of 3:1 and 2:1. Two types of notches were tested: one with a square-tipped profile and the other V-shaped with a 60º angle. The square shaped notches were prepared in two ways: one mechanically with a diamond disc tool and the other using blades as cores during the molding of the mortars. A PVC mold equipped with internal steel blades was created to produce samples notched and grooved in the mortar molding process. Stable conditions of crack propagation were established based on preliminary tests. The crack was found to propagate along an imaginary plane defined by the lateral grooves in the sample. The results indicated that the notch providing the best conditions of crack propagation stability is the V-shaped notch produced in the molding of the sample.
wedge splitting method; stable crack propagation; fracture energy; notch; mortar
