In this article on increasing the efficiency of steel combined structures, the tasks of rational design, regulation and control of structural parameters of elements, the use of steels with increased mechanical properties are considered. It is shown that for a six-span stiffening girder of a combined truss with elastic supports, which operates under a distributed load, the moment is 72 times smaller than the moment of a single-span beam. It is suggested to use high-strength steel for truss braces. Rationality criteria are proposed.
Wide spread of RC structures in construction projects indicates the necessity of their service life prolongation. Perspective possibility to increase strength of RC structures is use of external composite tapes. The article presents theoretical research on the effectiveness of strengthening of RC bended elements with the use of composite tapes. Work also includes comparative analysis on the basis of calculations, according to normative regulations.
Heat-resistant and high-alloy steels and alloys are difficult materials to machine. Optimizing the cutting parameters for such materials is a complex and multi-factorial technological process planning task. The paper describes the method of analysis of loading, thermodynamic and stress-strain state of a workpiece while cutting of typical representative of hard-to-cut materials (chromium-nickel alloy IN718) using finite element simulation. Influence of feed rate on cutting force and temperature in the zone of chip formation is given.
In order to obtain reliable information about the stress-strain state of the structure, subjected to loading, it is necessary to determine deformations` distribution. In some cases, it is almost impossible to assess stress-strain state with the traditional approaches. However, the DIC methods provide reliable information about the fields of displacement and deformation almost without limitations. Such approaches are rather effective for determination of the stress-strain state on smooth surfaces and in zones with stress concentrators.
The article is devoted to the regulation of the stress-strain state in the compressed elements of steel frames under full operating load. It is proposed to perform reinforcement of such elements with different end eccentricities of load application by rational regulation of the stress-strain state in the reinforcement elements. It is shown that the use of SDS adjustment for frame racks increases their bearing capacity and reduces deformability and welds. The new proposed technology of SDS regulation and possible constructive decisions are offered.
In the article, the algorithm for determination of stresses in anisotropic plates with elastic inclusions of another anisotropic material was developed on the basis of complex singular integral equations. The solving of integral equations has been carried out numerically using the method of mechanical quadratures. The strength analysis (calculation of strength) of composite plates with inclusions has been performed using the Hoffman criterion.
A method for estimating and predicting abnormal layer and pore pressure during drilling of oil and gas wells using finite element method is elaborated. Utilizing simulated stress-strain state of a real model of a massif it is shown the qualitative agreement of results with theoretical calculations. We identified evaluation and prediction of pore and layer pressures and reservoir in the rock massif.
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.
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.
The solving of the problem of horizontal deformation assessment by geodetic data based on the theory of quasiconformable reflections of surface has been disclosed