Tensile crack propagation in artificial specimens with two slits

The aim of this study was the development and fine-tuning of an effective methodology for the experimental and numerical investigation of the mechanical behaviour of rock bridges. The results of a series of uniaxial compressive tests are illustrated. At this preliminary stage of the research, the tests were performed on prisms manufactured from a mixture of cement and fine sand with two parallel slits in their central part. The problems associated with the choice of the material, the shape and size of the specimens are discussed. A computer code, BEMCOM, based on the Displacement Discontinuity Method and fracture mechanics was used to simulate the laboratory tests. The load levels triggering crack propagation and the crack trajectories were seen to be in good agreement with the experimental findings, confirming the validity of a fracture mechanics approach to the analysis of the mechanical behaviour of the material between systems of cracks.