Shear processes in anisotropic anticlinal geostructures under the gravity action

Shear deformation and fracture of three-dimensional anisotropic anticlinal geostructures under gravitational loading was simulated to study the theoretical and practical aspects of natural and man-made gravitational shear deformations and fractures based on the variational finite element method for solving the elasticity problem for multilayer orthotropic shells of rotation taking into account shear stiffness. The shear deformation of anisotropic anticlinal geostructures under the action of gravity depends on the shapes, sizes, structure, and elastic properties of differently oriented rocks that make up these geostructures. The stiffer and more compact anticlinal geostructures are subjected to the smallest shear deformation. While maintaining the general shape and stiffness of anticlinal geostructures, the largest shear deformations are observed in the lower middle part of the anticlinal geostructure. To be resistant to gravitational failure, the internal bearing layers of an anticlinal geostructure cannot consist of rocks softer than semi-hard dispersed rocks. The most important elastic characteristics for maintaining the stability of geostructures are Young’s modulus in the longitudinal direction and Poisson’s ratios and shear moduli in arbitrary directions. A decrease in Young’s modulus in the longitudinal direction and shear moduli, as well as an increase in Poisson’s ratios, especially in the internal bearing layers, can lead to catastrophic changes and failures in anticlinal geostructures. A decrease in the geostructure’s outer layer’s elastic properties in different directions leads to noticeable quantitative and qualitative changes in the nature of shear deformation of anisotropic anticlinal geostructures under gravitational loading.