考虑剪切非线性的复合材料渐进损伤模型

A Damage Model Considering Shear Nonlinearity for Progressive Failure Analysis of Composite Laminates

针对具有明显剪切非线性的复合材料,提出了一种考虑剪切非线性影响、能够分析和预测复合材料层合板极限承载能力的损伤模型.采用Ramberg-Osgood方程描述层合板剪切非线性的应力与应变本构关系,基于连续介质损伤理论建立了分析复合材料结构渐进损伤的三维有限元模型,采用已有的应变描述的三维Hashin失效准则和Ye-分层失效准则预测其损伤起始,引入损伤状态变量来分析层合板的损伤扩展,通过UMAT子程序实现了损伤模型的模拟,并运用黏性正则化方法确保计算收敛.同时,将模型运用于AS4/PEEK复合材料开孔层合板渐进损伤实验的模拟分析.结果表明,模拟计算结果与实验结果较吻合,对比已有模型的预测结果,所提出的方法具有更高的准确性.

A damage model considering the effect of shear nonlinearity was proposed to predict the ultimate load of laminated composites which exhibited significant shear nonlinearity.Shear nonlinearity constitutive relations for the laminates were defined with the Ramberg-Osgood equation.Based on continuum damage mechanics,a three dimensional FE model for damage analysis of composite materials was established.The onset of the damage of composite laminates was modeled with 3DHashin＇s initiation criterion and Ye criterion.The damage index was applied to analyze the damage extension.The model was implemented with a UMAT subroutine.The convergence was improved by using the viscous regularization method.The model was applied to the progressive failure analysis of notched AS4/PEEK composite laminates.Simulation results agreed well with the experimental date,which indicated that the proposed model had a better accuracy than the model published.