材料本构模拟的桁架模型和屈曲问题分析

Simulation of Material Constitution and Buckling Analysis Based on a Truss Model

摘要: 本文建立桁架模型模拟材料的力学行为，针对正交各向异性和各向同性材料，构建相应的框架模型，并依据材料的本构关系(胡克定律)确定模型参数。本文进一步讨论了材料泊松比对模型构造的影响，验证了模型的适用性和桁架模型模拟力学行为的合理性。对于各向同性材料，本文应用该桁架模型对材料曲屈行为进行了研究，将桁架模型的基本参数确定与材料杆件屈曲行为结合起来，建立框架模型曲屈失效的判据，探讨了杆件失效的材料细观机制。

Abstract: The mechanical behavior of the truss model is simulated, and the corresponding frame model is constructed for the orthogonal anisotropy and the isotropic material in this paper. The model parameters are determined according to the constitutive relation of the material (Hooke’s law). The influence of the Poisson’s ratio on the model structure validates the applicability of the model and the rationality of the truss model to simulate the mechanical behavior is also discussed. This paper uses the truss model to study the behavior of the material flexing for the isotropic material, the basic parameters of the truss model and the buckling behavior of the material bar are combined to establish the criterion of the flexion failure of the frame model. Failure of the material mesoscopic mechanism is finally discussed.