On the transformation of the passive deformation area in a nonlinear elastic anisotropic body with crack

1Kaminsky, AA
1Kurchakov, EE
1S.P. Timoshenko Institute of Mechanics of the NAS of Ukraine, Kyiv
Dopov. Nac. akad. nauk Ukr. 2019, 9:20-33
https://doi.org/10.15407/dopovidi2019.09.020
Section: Mechanics
Language: Russian
Abstract: 

The deformation of a nonlinear elastic orthotropic thin plate with a crack of normal separation is considered. It is assumed that there is a prefracture zone in the crack tip. It is assumed that the plane stress conditions are applicable. The boundary-value problem for the plate is stated in terms of the displacement vector. Governing equations are stated to describe the dependence between the stress and the strain tensors. Constitutive equations are used as an interlink between components of the stress vector at the points on the opposite faces of the prefracture zone and components of the mutual displacement vector for these points. The partial derivatives in the equations are transformed into the finite differences using the mesh discretization. Terms “active” and “passive” are introduced for the deformation according to its action on the nonlinear elastic anisotropic body. The problem is solved using the additional stress method that was earlier proposed by the authors of this work. The boundary-value problem solution allows concluding that a passive deformation area appears around the prefracture zone. Stresses in this area diminish, as the loading parameter grows. An analysis is given for the extents of the passive deformation area. In particular, it is investigated how it changes its dimensions and form depending on the loading parameter. A comparison is made between the passive deformation area and the nonlinearity area around the crack tip. It is shown that there are some differences between them.

Keywords: constitutive equations, crack of normal separation, nonlinear elastic orthotropic body, passive deformation area, prefracture zone
References: 

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