The estimation of load-carrying capacity of forest machine roll-over protective structure from the point of fracture mechanics
This paper deals with the application of main fracture mechanics equations for estimation of cracklike defects influence over forest machine roll-over protective structure survival. The definition of breaking points in protective structure was done by finite elements method. Stress intensity factor was defined as the estimation criterion. It relate the local mechanical state near the crack tip to macroscopic characteristics such as the geometry of a body and loading, and enable to give simple description of crack growth process. The stress intensity was estimated by finite element method. Breaking lengths were calculated for different types of cracks: through, edge and semielliptic. As shown, the presence of cracklike defects, even small length, rather reduces the level of breakdown load.