考虑剪切非线性的复合材料层合板渐进损伤数值模拟

Numerical simulation of progressive damage of composite laminates considering shear nonlinearity

基于连续损伤力学的基本原理,建立了考虑剪切非线性的三维渐进损伤模型,分析预测复合材料层合板的力学行为、失效载荷以及失效机理。选用高阶指数函数描述复合材料的剪切非线性行为,考虑复合材料刚度渐进和突然折减的组合方式来表征损伤过程中材料的刚度变化,编制了UMAT子程序,采用ABAQUS软件对带孔AS4/PEEK复合材料层合板进行渐进损伤失效分析。本文提出的模型与传统不考虑剪切非线性的模型相比,仿真结果精度更高,与已报道试验对比误差值小于4%。模拟结果显示,孔径越大,损伤发生前,圆孔附近的应力极限值越大,应力分布梯度越大,层合板承载能力越小。当采取[±45]_(2S)铺层方式时,仿真应力与试验结果具有很好的一致性,也进一步验证了模型的适用性和准确性。

Based on the basic principle of continuous damage mechanics,a three-dimensional progressive damage model considering shear nonlinearity is established to analyze and predict the mechanical behavior,failure load and failure mechanism of composite laminates.The high-order exponential function is used to describe the shear nonlinear behavior of composite materials.Considering the combination of progressive and sudden reduction of composite stiffness to characterize the stiffness change of materials in the damage process,a UMAT subroutine is compiled,and ABAQUS software is used to analyze the progressive damage failure of perforated AS4/PEEK composite laminates.The model proposed in this paper has higher accuracy than the traditional model simulation results without considering shear nonlinearity,and the error value is less than 4%compared with the reported experiments.The simulation results show that the larger the aperture,the greater the stress limit around the inner hole before the damage occurs,the greater the stress distribution gradient,and the smaller the bearing capacity of the laminated plate.When the[±45]2S ply is adopted,the simulated stress is in good agreement with the experimental results,which further verifies the applicability and accuracy of the model.