基于数字图像相关法的复合材料结构失效分析

针对纤维增强复合材料失效机理复杂的问题,采用数字图像相关法对拉伸试验中的复合材料表面位移进行数字化处理,建立了基于Hashin改进准则的结构模型,对比试验和仿真结果,分析试件的失效过程和机理。运用蒙特卡洛方法和有限元法,讨论并分析影响结果精度的因素。结果表明,数字图像相关法能够用于观察和分析复合材料结构的失效过程;基于Hashin改进准则的仿真模型与试验结果一致,可以作为进一步细观力学分析的基础;相对于其他结构参数,纵向拉伸强度对结果精度的影响更大。该结果可为复合材料可靠性分析提供理论参考。

Failure analysis of fiber reinforced composite structures using a digital image correlation method

Aiming at the complicated mechanism for the failure problem of fiber reinforced composite,a digital image correlation ( DIC) method was used to obtain the evolution of strain field on specimen surface of the laminated sheet tensile test. A structural model was established as well based on improved Hashin criteria.The simulation results were compared with experimental ones to an-alyze the failure process and mechanism of the specimen.Based on Monte Carlo method and finite element method,the influence of Micro-parameters on the accuracy of the result was discussed and analyzed.The results indicate that the DIC is capable of analyzing and predicting the structural failure process.The established model based on improved Hashin criteria is in good agreement with the experimental results,which can be used as a basis for the further research on micromechanics.Compared with the other structural pa-rameters,longitudinal tensile strength has a greater impact on the accuracy of the results.The results can provide theoretical reference for reliability of the composite materials.