多跨加筋板的动态裂纹扩展

提出了一种加筋板数值分析中筋条与板相互作用的计算模型,用有限差分法对多跨加筋板结构进行了动态裂纹扩展分析计算。当筋条位于板的边界时,筋条的作用可以作为边界力处理;当筋条位于板的内部时,其作用可作为局部作用的类似体积力进行分析。按照这种模型对多跨加筋裂纹板进行静态与动态断裂分析。计算结果表明:筋条具有降低裂纹尖端应力强度因子作用,在裂纹动态扩展情形还能降低裂纹扩展速度甚至止裂。

DYNAMIC FRACTURE ANALYSIS OF A MULTIPLE-STIFFENED PANEL WITH A CENTRAL CRACK

A model of the action and reaction of the center-cracked panel with the multiple-stiffeners has been proposed. The Finite Difference Method has been used for the dynamic fracture analysis. When the stiffeners are on the boundaries of the panel, the action of the stiffeners is treated as the boundary forces. On the other side, when the stiffeners are in the domain of the panel, the action of the stiffeners at every rivet on the panel is treated as an analogous local body force in the equations of motion. According to this model, the multiple-stiffened panel with a central crack can be analyzed in the static and dynamic cases. The computational results show that the stiffeners can be used for reducing the stress intensity factors in the static or dynamic cases. Furthermore, the stiffeners can be also used to reduce the crack velocity or arrest the crack propagation. The influence of the cross area and the position of the stiffeners has been investigated. When the stiffeners have large cross area (or large Young's modulus), and the internal stiffener lies close to the crack tip, the crack arresting effect will be more obvious.