Impact Damage in Curved Laminated Composites

对纤维增强层合复合材料的冲击损伤及其曲率和铺层方向对损伤的影响进行了分析和实验研究。该分析将能够预测平板和弯曲复合材料结构在瞬时动力冲击下的损伤程度和类型。在考虑材料和几何非线性的情况下，采用基于暂态动力分析的有限元方法计算层合板的应力和应变。通过建议的失效分析，将预测失效并模拟损伤进程。失效分析将包括用于面内损伤的连续介质力学方法和用于分层、生长和停滞的动态断裂模型。在本次调查过程中，将编制一个基于分析的用户友好的计算机代码。该程序可以作为一种设计工具，用于评估给定复合材料结构的抗冲击性能，并为给定的应用选择复合材料结构的最优配置。还将进行平板和曲面组合结构的实验测试，以评估模型和计算机模拟的有效性。

An analytical and experimental investigation will be performed to study the impact damage in fiber-reinforced laminated composites and the effects of their curvature and ply orientation on the damage. The analysis will be able to predict the extent and the types of damage in flat and curved composite structures due to transient dynamic impact. Stresses and strains in laminates will be calculated by a proposed finite element method which is based on transient dynamic analysis with the consideration of material and geometric nonlinearities. Failure will be predicted and damage progression will be simulated by the proposed failure analysis. The failure analysis will include a continuum mechanics approach for in-plane damage and a dynamic fracture model for delamination growth and arrest. A user friendly computer code based on the analysis will be developed during the course of this investigation. The code could serve as a design tool to evaluate the impact resistance of given composite structures and to select optimal configurations of composite structures for a given application. Experimental tests of flat and curved composite structures will also be performed to assess the validity of the model and the computer simulations.