finite element method

Exterior boundaries of the objects in modeling with finite element method

The problems of wave field modeling with finite element method in unbounded domains and methods to deal with them are analyzed. To obtain optimal solution, using of infinite elements is proposed on the boundaries of the modeled area combined with standard finite-element modeling inside the area. It is important however to choose the shape functions of infinite elements depended on the conditions of wave decay at infinity.

The strain-stress state modelling of the sedimentary complex in collision zone and dynamic conditions of early thrusts formation in the Ukrainian Carpathians

Series of the finite-element 2D-models of thrusts in the flysh basin on the base of elastoplasticity equations for piecewise-homogeneous medium are proposed. Using computer modelling the formation mechanism of thrusting in the Ukrainian Carpathians during Early Cretaceous is improved. Within the framework of the complex analysis the fields of calculated stresses and strains of the sedimentary rocks in the collision zone are studied. The place of first thrusts with general Carpathian orientation, the role of tectonic displacements and paleo-basin basement morphology are determined.

Problem of assessing of the earth’s surface strain state by geodetic data

Analysis of nature of estimation of the earth’s surface deformations by geodetic data and the methods to solve this problem has been done in recent geodynamical research. The necessity of improvement of existing methods of data processing has been substantiated. The alternative approach to solving the problem based on the theory of surface reflection and the ways of its implementations are suggested.

The stress-strain state modelling of the autochthonous sedimentary complex in the dynamic influence zone of the thrust wedge

Purpose. Computer modelling in the framework of continuum mechanics is a powerful tool to obtain qualitative and quantitative deformation parameters in the geological media. The purpose of this work was to study stress and strain fields of the sedimentary autochthonous complex owing to moving a thrust wedge. Subject of inquiry is layered rocks with different geometrical and mechanical properties bounded by the basement of the peleobasin and compressive thrust wedge taking into account the gravitational forces and contact frictions. Methodology.

Modeling elastic-dynamic effects of the crust under nuclear power plant (on the example of Chornobyl NPP)

Purpose. The aim of study is to create the method of seismic wave fields modeling for a broad class of vertically and horizontally inhomogeneous layered media. Simulation will make it possible to more precisely assess the characteristics of sedimentary strata in the study of the transmission characteristics of the environment under the engineering structures. Methodology. At modeling in engineering seismology should be used a wide frequency range (from 0 to 200 Hz) to study all possible effects on engineering structures.

Modeling stress-strain state bases of engineering constructions for evaluation of seismic hazard

Purpose. The aim of this work was to evaluate changes in the transfer characteristics of the seismic environment with additional loading of massive engineering structures. This analysis will help to more accurately assess the characteristics of sedimentary layer in the study of the transfer characteristics of environment under the engineering structures already at the design stage of construction. Methodology. Frequency characteristic of environment was obtained by solving the direct dynamic seismic problem.

Problems and prospects of estimating Earth deformation fields from geodetic data

Aim. Analysis of the current state of solving the problem the estimating of earth deformation fields based on continuum mechanics, improving traditional methods the estimating of horizontal deformations, definition an alternative approach and justification of ways and the algorithm of solving the problem based on it. Methodology and results. The analysis showed some shortcomings of traditional solving of the problem. In order to minimize their impact the improved method of mathematical and cartographic modeling of linear deformations is proposed.