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在连续损伤力学和塑性力学框架内,建立一个同时考虑塑性效应和损伤累积导致材料属性退化的复合材料弹塑性损伤本构模型。基于最近点投影回映算法,开发本构模型的应变驱动隐式积分算法以更新应力及与解答相关的状态变量,并推导与所开发算法相应的数值一致性切线刚度矩阵,保证有限元分析采用NewtonRaphson迭代法解答非线性问题的计算效率。采用断裂带模型对已开发的本构模型软化段进行规则化,以减轻有限元分析结果的网格相关性问题。对损伤变量进行粘滞规则化,并推导出相应的粘滞规则化数值一致性切线刚度张量,解决了在有限元隐式计算程序中采用含应变软化段本构关系的数值分析由于计算困难而提前终止的问题。开发包含数值积分算法的用户材料子程序UMAT,并嵌于有限元程序Abaqus v6.14中。通过对力学行为展现显著塑性效应的AS4/3501-6V型开口复合材料层合板的渐进失效分析,验证本文提出的材料本构模型的有效性。结果显示,预测结果与已报道的试验结果吻合良好,并且预测精度高于其他已有弹性损伤模型。表明已建立的弹塑性损伤本构模型能够准确预测力学行为,展现显著塑性效应的复合材料层合板的破坏荷载,为其构件和结构设计提供一种有效的分析方法。
In the framework of continuous damage mechanics and plastic mechanics, a constitutive model of elastoplastic damage of composite material is established, which considers both plasticity and damage accumulation. Based on the nearest-neighbor projection-projection algorithm, a strain-driven implicit integration algorithm of the constitutive model is developed to update the stress and the state variables associated with the solution and to derive the numerical consistent tangent stiffness matrix corresponding to the developed algorithm to ensure that the finite element analysis NewtonRaphson Iterative Method to Solve the Computational Efficiency of Nonlinear Problems. The fractured zone model is used to regularize the softened section of the constitutive model developed to reduce the grid dependence of the finite element analysis results. The viscous regularization of damage variables is carried out and the tangential stiffness tensor is deduced. The numerical analysis of the constitutive relation of strain softening section in implicit finite element program is solved, which is due to the difficulty of calculation The problem of termination. The user material subroutine UMAT, which contains a numerical integration algorithm, is developed and embedded in the finite element program Abaqus v6.14. The asymptotic failure analysis of AS4 / 3501-6V open-ended composite laminates with significant plastic effect on mechanical behavior was carried out to verify the effectiveness of the proposed material constitutive model. The results show that the predicted results are in good agreement with the reported test results and the prediction accuracy is higher than other existing elastic injury models. It is shown that the established constitutive model of elasto-plastic damage can accurately predict the mechanical behavior and show the damage load of the composite plastic laminates with significant plastic effect, providing an effective analytical method for the structural and structural design of the composite.