复合材料后压力框加筋元件双轴拉伸试验与模拟

试验针对应用在飞机后压力框上的碳纤维织物复合材料的力学特性和设计压力框壳体加强筋的刚度匹配问题,本文设计了十字形的试件,并开展了双轴拉伸试验,测试分析了试件中心位置含有不同尺寸加强筋时对刚度和强度的影响。依照试验条件,建立有限元模型,以中心位置未加筋试件为基准,探讨了两种尺寸筋条增强效果的差异。试验与模拟结果表明:在双轴拉伸载荷作用下,帽型加强筋明显提高了试件刚度和强度;两种筋条尺寸的差异对于试件刚度和强度的影响不明显;根据重量最小的原则,在同等条件下使用较小尺寸加强筋更为合适;有限元模拟与试验结果吻合良好,验证了本文提出的试验和模拟方法可用于复杂应力条件下织物复合材料结构的力学性能分析。

Biaxial Tensile Test and Simulation of Rear Pressure Bulkhead Reinforcement Components with Composite

In order to study the mechanical characteristics of carbon fiber composite material applied to plane rear pressure bulkhead and stiffener's stiffness matching in pressure bulkhead housing design, a cruciform specimen was designed and biaxial tensile experiment was carried out to test and analyze the effect of stiffeners mounted on centre position of specimen and with different sizes on the stiffness and strength. Based on experimental conditions, a finite element model was established to discuss the effect of cap-type stiffener with two different dimensions on performance enhancement, based on comparing with that of specimen without stiffener at centre position. Experimental and numerical results show that the cap-type stiffener obviously improves the stiffness and strength of specimen under the biaxial tensile loading, and the size difference of cap-type stiffeners doesn't influence the strength significantly. According to the principle of minimum weight, the smaller size of cap-type stiffener is more suitable. Results obtained from finite element simulation are in good agreement with that of experiments. Therefore, above proposed experimental and numerical methods can be used for mechanical characteristics analysis of fabric composite structure under complex stress condition.