含冲击损伤复合材料加筋层板压缩剩余强度

 将复合材料加筋层板受低速冲击后的损伤区域描述为一个椭圆形弹性核，材料在核区的弹性模量下降由冲击表面的凹坑深度确定。利用含任意椭圆核各向异性板杂交应力有限元来模拟含损伤区域，杆单元来模拟筋条，钉单元模拟铆钉（胶层）和常规8节点等参单元模拟其余无损区域，建立起含低速冲击损伤复合材料加筋层板的力学响应分析方法。利用基于特征曲线概念的点应力判据、最大正应力判据和最大剪应力判据分别预测蒙皮的破坏、筋条的破坏和铆钉（胶层）的破坏，从而预测加筋层板在压缩载荷下的剩余强度，获得了与试验相吻合的结果。最后讨论了损伤尺寸、损伤形态、铺层比例等参数对加筋层板剩余强度的影响。

Residual Compressive Strength of Stiffened Composite Laminates with Impact Damage

By describing the damage zone of the impacted laminate as a soft elliptical inclusion of the material,the elastic modulus is determined by the dent depth on the impact face.By using the hybrid stress finite elements with an arbitrary elliptical inclusion for anisotropic plates to model the damage zone,the bar elements to model the stringers,the nail elements to model the rivets(or adhesives) and eight node equal-parametric elements to model other regions,an analytical method is established for the stress an...