In 3-D analyses of rock slopes there’re can be numerous sliding paths a long a coplanar nonpersistent discontinuity with a known strike. This paper describes an approach for the determination of a most probable sliding path. For this particular study, several blocks of gypsum with the dimensions of 15×15×15 cm containing coplanar non-persistent open joints were fabricated. The models have vario...

We here report on a detailed experimental study whose goal is to investigate spontaneous crack propagation in bonded and intact materials subjected to quasi-static far-field tensile loading. The cracks nucleate from a tiny circular hole and are triggered by an exploding wire. They subsequently propagate under the action of a constant far-field load. Dynamic photoelasticity in conjunction with h...

crack identification is a very important issue in mechanical systems, because it is a damage that if develops may cause catastrophic failure. in the first part of this research, modal analysis of a multi-cracked variable cross-section beam is done using finite element method. then, the obtained results are validated usingthe results of experimental modal analysis tests. in the next part, a nove...

The El Haddad equation permits to deal simply with both short and long cracks, and we have recently suggested a generalization for finite life, defining a “finite life intrinsic crack size”, as a power law of number of cycles to failure. Here, we derive the corresponding crack propagation law, finding that it shows features similar to Paris’ law in the limit of long cracks, but shows some depen...

When a femtosecond laser pulse is focused inside a LiF single crystal, four cracks are generated in the <100> directions from the photoexcited region. The time-resolved observation have elucidated that the tensile stress in the laser induced stress wave induces the generation and propagation of the cracks. In this study, to investigate the possibility of control of laser induced cracks inside s...

numerical methods such as boundary element and finite element methods are widely used for the stress analysis in solid mechanics. this study presents boundary element method based on the displacement discontinuity formulation to solve general problems of interaction between hydraulic fracturing and discontinuities. the crack tip element and a higher order boundary displacement collocation techn...

the problem of crack identification in continuous beam like structures is considered. the cracks’ locations and their depths are identified by employing experimental modal test results performed on the structure. the cracks are modeled using generic elements to include the coupling effects between shear forces and bending moments at the crack section. in the identification procedure eigen- sens...