Alternative Model of Isotropic Material with Different Modulus

The study suggests a model of isotropic heterogeneous material (isotropic material with different modulus of elasticity in different directions). In this model the defining relations are built by analogy with the different-modular theory of elasticity developed by S.A. Ambartsumyan. The approach is based on the generalized stiffness decomposition, which determines the presence of bonds between different directions of deformation. This makes it possible to deal with the uncertainty when choosing the coefficients in the equations relating stresses and deformations in the case of a complex stress-strain state. Signs of longitudinal deformations are taken as criteria. Some limitations on the technical characteristics of isotropic, different-modular materials --- elastic modulus and coefficients of transverse strain for tension and compression result from the proposed relationships. The given model helps process experimental data on graphites, and the study gives the results of the processing obtained for some types of stress-strain state under proportional loading

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