复合材料脱层屈曲的摄动解

Perturbation Solution of the Delamination Buckling for Composite

用摄动法求解了 3 D复合材料中有纤维搭桥的圆形脱层的屈曲问题。搭桥纤维被视为连续分布于脱层面上的线性弹簧。给出了脱层屈曲临界载荷、挠度曲线与脱层半径、搭桥因子等的封闭关系式。根据脱层夹支边界条件以及脱层只能向一个方向挠曲的约束条件 ,导出了一个特征长度 a* ,当脱层半径超出 a*时 ,脱层屈曲时将发生靠近边界区域的接触现象 ;当脱层半径小于 a* 时 ,脱层屈曲将跨越整个脱层区域 ,并随着半径的减小 ,脱层屈曲的临界载荷将逐渐提高。

Axisymmetric buckling of a circular delamination bridged by linear fibers in 3D composites is studied by a perturbation method.The through thickness fibers are assumed to provide linear restoring traction resisting the deflection of the delaminated layer distributed continuously on the delamination surface.The closed form solutions of the critical load and the deflection contour of the delamination buckling decided by delamination radius,and the bridg ing factor are obtained.With the boundary condition that the ends of the delaminated layer are clamped and under the constraint condition that the deflection of delamination can occure in only one direction,there exists a characteristic length a * for delamination buckling:if the radius a of the delamination crack exceeds a *,the delamination buckling will be accompanied by the contact between delaminated layer and substrate within boundary region;if it does not exceeda ,the buckling will span the whole delamination region,and the critical load of delamination buckling will increase minotonically while a decrease.