Research on crack-propagation life for perforated ship stiffened plate

Perforated ship stiffened plate is the basic component in ship and ocean engineering and is of great importance to study the fatigue crack propagation life due to cyclic loading. To evaluate the safety of ship stiffened plate based on the fatigue crack propagation method, the key issue is to study the crack propagation rate for stiffened plate subjected to cyclic loading. In this paper, the fatigue crack propagation life has been calculated using elasto-plastic theory and Paris formula. The virtual crack closure technique (VCCT) was used to research crack propagation life of stiffened plate, by means of calculating the energy release rate and with the method of meshing division on crack propagation path to simulate crack propagation process. The finite element analysis software MSC. Marc was applied on fatigue crack propagation life for stiffened plate taken into account the influence of stiffener. It has been found that stiffener can significantly reduce the crack propagation life.