三维编织复合材料矩形梁与T型梁准静态弯曲实验及有限元分析

Quasi-Static Bending Testing and Finite Element Simulation of 3D Braided Composite Rectangular Beam and T-beam

采用MTS 810.23型材料试验机,研究三维编织复合材料矩形梁与T型梁的准静态三点弯曲行为,分析得到两种梁的破坏失效机理存在一定差异,矩形梁在实验中位移达到最大而最终失效,T型梁在实验中筋高产生纤维断裂而最终失效.实验表明筋高可显著增强梁抗弯刚度.依据三维编织复合材料细观结构建立单胞模型,运用ABAQUS有限元软件与用户子程序交互作用,进一步分析在准静态三点弯曲实验过程中材料的应力分布情况,揭示材料破坏机理和最终失效模式的缘由.有限元分析所得结果与实验结果具有较好的一致性,说明所使用的有限元分析法有效,可以用于进一步研究三维编织复合材料的力学性能.

The MTS 810.23 material tester was employed to test the quasi-static bending behavior of 3D braided composite rectangular beam and T-beam. Some differences of the failure mechanism were found between these two beams. It was found that the rectangular beam failed as the largest deformation reached, compared with that of the T-beam was the fiber breakage of web. The test indicated that the web can significantly increase the flexural rigidity. Finite element method （FEM） based on unit-cell of the structure of 3D braided composite model and interaction between ABAQUS and user subroutine were used for further analysis of stress distribution, the cause of damage mechanism and failure mode was revealed. The FEM result was good agreement with experimental result, which proved the validity of FEM and it could be extended to study the mechanical properties of 3D braided composites.