Finite deformations of thin anisotropic and composite shells and defining relations

Structure of nonlinear elastic relationships for the highly anisotropic layer of a nonthin shell

“…The method of deriving the simplified physical relations is based on employing the features of a unidirectionally reinforced material, namely high rigidity in the fiber direction as compared to the rigidity in the transverse direction and in shear [14][15][16]. Thus, for further analysis, we assume that C n >>C 22 , C44, C 55 , C66; C 22 >C44, C s5 , C66; C 44 >C 55, C si.…”

“…For example, in [ 13], the experimental results for CFRP beyond the range of linear strain diagram were given. A comparison of the results obtained from a polynomial elastic potential with the experimental data shows that such an approach, in some cases, leads to great distinctions, both quantitative and qualitative, between the predicted and actual strain diagrams.In [14][15][16], an asymptotic method for analyzing the constitutive relations was developed, their classification depending on the properties of CM was carried out, and different types of such relations containing functions of small number of argumants (one or two) were obtained.In the present study, this method is used to construct simplified models of deformation for a transversely isotropic CM for cases different from those considered in [16]. These models are then used to formulate the physical relations for the material of a shell calculated by one of the shear theories.…”