受弯脱层层板后屈曲有限元分析

脱层是复合材料层板结构中主要的缺陷形式之一。当脱层层板受到压力载荷的作用会造成脱层的局部屈曲和扩展，从而使结构的强度和刚度大为降低。含脱层层板的弯曲问题包含了脱层的压缩问题，却比压缩问题更加复杂。本文对含穿透脱层层板在纯弯载荷作用下的后屈曲问题进行了基于一阶剪切层板理论的几何非线性有限元分析，运用虚裂纹闭合技术求解了纯弯载荷作用下的脱层尖端的能量释放率各型分量，并用脱层扩展判据求解了脱层起始扩展载荷。

Finite Element Postbuckling Analysis of Delaminated Plate under Bending Loads

Delamination is one of the most frequently encountered types in structures of composite laminates. Local buckling and growth of delamination under compressive loads will decrease the strength and stiffness greatly. Bending problem of delamination includes compressive problem of delamination and it is more complicated than the later. In this paper, a finite element method is used to analyze the postbuckling problem of laminatien with through-width de-lamination under pure bending loads. The one-dimensional nonlinear geometric finite element model is developed based on the first-order shear deformation plate theory. The individual components of energy release rate are obtained according to virtual crack closure technique, and the critical initial growth loads are obtained from a certain delamination growth rule.