腹板开口对复合材料梁腹板剪切承载性能的影响

针对平面编织复合材料梁腹板结构剪切载荷作用下的面内剪切屈曲失稳和后屈承载能力问题，采用实验与有限元方法进行了研究。结合实验所得应变分布规律与有限元分析所得失稳模态分析了梁腹板结构剪切失稳特点。后屈曲承载分析中引入了平面织物复合材料Hashin失效准则，获得的结构主要失效模式包括纬向纤维压溃和经向纤维拉断，与实验结果符合良好。基于经实验结果验证的有限元模型进行了参数化研究，分析了腹板开口尺寸和开口形式对平面织物复合材料梁腹板剪切稳定性、承载能力和破坏模式的影响。研究结果可为复合材料结构设计和强度评估提供参考。 

Effects of web cutout on bearing performance of composite beam webs under shear load

The buckling unstability and post-buckling bearing capacity of plain woven composite beam webs under shear load were investigated through experiments and finite element method in this paper. Based on characteristics of the experimental strain results and numerical buckling mode of the finite element analysis, the buckling characteristics of the composite beam webs were analyzed. Hashin failure criteria for plain woven composite materials were imported in the post-buckling bearing analysis, and the main failure modes of the webs from the numerical results are fiber tensile failure in the warp direction and fiber compressive failure in the weft direction. The simulated failure behavior of the webs agrees well with the experimental results. A parametric study based on the experimentally validated finite element model was conducted to investigate the effects of web cutout size and form on the stability, bearing capacity and failure mode of plain woven composite beam web under shear load. The research results provide reference for the design and strength analysis of composite structures.