Energy coefficient method for modeling nonlinear constitutive relations of lattice truss materials

作者：Chen, Xueyan; Tan, Huifeng^*; Wei, Jianzheng

来源：Archive of Applied Mechanics, 2018, 88(5): 805-817.

DOI：10.1007/s00419-018-1343-4

• Boundary coefficient
• Energy calculation
• Ramberg-Osgood relation
• Geometrical nonlinear coefficient
• Nonlinear constitutive relations

In this paper, an energy coefficient method is presented to predict the nonlinear constitutive relations of stretching dominated lattice materials. The proposed method adopts a process based on boundary coefficient and energy calculation to obtain the effective elastic stiffness of lattice truss materials. Furthermore, the Ramberg-Osgood relationship and the geometrical coefficient is introduced to establish the nonlinear relationship between macro-stress and macro-strain. The method is used to determine the stiffness matrix of the pyramid lattice material and the nonlinear constitutive relationships of the octet lattice material and the 3D Kagome core sandwich panels under uniaxial compression and pure shear, respectively. The obtained results agree well with the related experimental results. This agreement validates the energy coefficient method.

• 出版日期2018-5
• 单位哈尔滨工业大学