scholarly journals The study of tensile deformations at the lower boundary of the package of asphalt concrete layers based on tests of the installation of shock loading

2018 ◽  
Vol 5 (4) ◽  
Author(s):  
Artem Tiraturyan ◽  
Akulov Vladimir ◽  
Ilya Bodrov ◽  
Anastasia Simakova ◽  
Marina Farnieva
Keyword(s):  
Mathematical Model ◽  
Russian Federation ◽  
Asphalt Concrete ◽  
Strain State ◽  
Shock Loading ◽  
Lower Boundary ◽  
Stress Strain ◽  
The Road ◽  
Stress Strain State ◽  
The Russian Federation

Currently, in the road sector of the Russian Federation, there has been a modernization of the system of operation of the road complex. In this regard, there is a tendency to introduce new technologies for monitoring the condition of road pavements. One of these is the high-performance FWD dynamic loading drum set, which allows you to measure pavement trough bowls. In this paper, examples and models are given to evaluate the reliability of the results from the FWD installation, as well as the dependence of the experimental and software data on the deflection bowl of the road structure. The relevance of the study is due to the fact that a significant reworking of methods for calculating non-rigid pavements and the creation of a new method for predicting fatigue damage is being carried out. Nevertheless, the application of this empirical dependence requires an assessment of its adequacy and the possibility of using layers for structures and materials used in the practice of the Russian Federation. It is possible to solve this problem by comparing the actual values of tensile deformations with the calculated values determined on the basis of the mechanical-mathematical model of the stress-strain state of the road structure. The sections of the M-4 “Don” and M-3 “Ukraine” federal highways were chosen as experimental constructions that were used to work out methods for calculating tensile deformations. Measurements at these sites were carried out by installing shock loading FWD every 100 m. At the same time, at each impact impact, the plates of the coating deflection were recorded. Based on the resulting bowls of the deflections, tensile deformations were calculated at the lower boundary of the package of asphalt concrete layers. Next, a statistical processing of the measurements of the deflection bowl was made. To assess the adequacy of the results obtained, the American mathematical model MnLayer was applied. During the calculation, the main parameters of the stress-strain state, including tensile deformations, were determined. Analyzing the data obtained from the calculation of tensile stresses in mathematical models of given road structures, a comparative graph was constructed illustrating the dependence of the actual deflection cup indicators with those obtained in the MnLayer program.

scholarly journals Mathematical Models and Evaluation Software for Stress-Strain State of the Earth’s Lithosphere

2019 ◽  
pp. 51-66
Author(s):  
Alexander O. Faddeev ◽  
Svetlana A. Pavlova ◽  
Tatiana M. Nevdakh
Keyword(s):  
Mathematical Model ◽  
Strain State ◽  
Uniform Grid ◽  
Shear Stresses ◽  
Stress Strain ◽  
Gravitation Field ◽  
Vertical Movements ◽  
Stress Strain State ◽  
The Earth ◽  
Viscous Shear

Introduction. For the purposes of this article, geodeformation processes mean processes associated with deformations arising from the movement of species and blocks of the lithosphere at various depths, including surfaces. The objective is to reconstruct geodynamic stress fields, which cause modern shifts and deformations in the Lithosphere. A mathematical model and software for estimating the stress-strain state of the Earth Lithosphere are considered. Materials and Methods.For mathematical modeling of stresses, isostatically reduced data on abnormal gravitation field were used. The methods of continuum mechanics and methods of the theory of differential equations were used to design a model for estimating the stressstrain state of the Earth Lithosphere. For processing input, intermediate and outcoming data, the Fourier transform method of spectral analysis for constructing grid functions and spectral-temporal method were used. To model for the stress-strain state of the Lithosphere globally, stress calculation was corrected on the basis of sputnik-derived velocity data at the surface of the earth crust. The data on the rates of horizontal and vertical movements at the surface of the Earth crust were processed to obtain a distribution of velocities in the uniform grid embracing longitudes and latitudes. The processing procedure was carried out on the basis of the Kraiging method. The software was developed in Borland Delphi 7.0 programming environment. Results. Based on the data on the abnormal gravitation field in isostatic reduction and information on the distribution of velocities of horizontal motions on the surface of the Earth crust, a mathematical model of the stress-strain state of the Lithosphere was constructed. With the help of the obtained mathematical model and software complex, the stress-strain state of the Lithosphere was calculated at various depth using elastic and elastic-viscous models, and maps of equipotential distribution of shear elastic-viscous deformations in the lithosphere at the depth of 10 km were constructed. Discussion and Conclusion. The presented mathematical model and software allow restoring fields of both elastic and elastic-viscous deformations that is fundamental for quantification of elastic-viscous shear stresses deep in the Earth Lithosphere.

scholarly journals A BEM-based mathematical model of the human cornea stress-strain state

2019 ◽  
Author(s):  
N. A. Babailov ◽  
A. E. Bogachev ◽  
S. A. Korotkih ◽  
O. A. Nefedova ◽  
L. F. Spevak
Keyword(s):  
Mathematical Model ◽  
Strain State ◽  
Human Cornea ◽  
Stress Strain ◽  
Stress Strain State

scholarly journals Stress-strain state of ship hull structures restored using polymer coating

2021 ◽  
pp. 12-17
Author(s):  
С.И. Корягин ◽  
О.В. Шарков ◽  
Н.Л. Великанов
Keyword(s):  
Mathematical Model ◽  
Polymer Coating ◽  
Strain State ◽  
Metal Layer ◽  
Adhesive Layer ◽  
Metal Structure ◽  
Polymer Coatings ◽  
Calculation Algorithm ◽  
Stress Strain ◽  
Stress Strain State

Применение полимерных покрытий для ремонта корпусных конструкций выдвигает как актуальную задачу определения прочностных характеристик конструкций с покрытиями. Наличие отверстий, сквозной коррозии, являющихся концентраторами напряжений, делает эти места наиболее опасными, с точки зрения потери прочности, герметичности. Чаще всего разрушение происходит по адгезионному слою. Представлена математическая модель, учитывающая сосредоточенные усилия на концах адгезионного слоя композиционной конструкции типа «металл-покрытие». Проведены расчеты нормальных и касательных напряжений. Наибольшие значения напряжений в полимерном покрытии получены на кромке отверстия в слое металла. В результате анализа установлено, что увеличение перекрытия полимерным покрытием контура отверстия и удаленность от контура отверстия приводят к существенному уменьшению величин напряжений. Разработанная математическая модель и алгоритм вычислений позволяют расчетным путем определить напряженно-деформированное состояние металлической конструкции с отверстием и полимерным покрытием. The use of polymer coatings for the repair of hull structures puts forward as an urgent task to determine the strength characteristics of structures with coatings. The presence of holes, through corrosion, which are stress concentrators, makes these places the most dangerous, in terms of loss of strength, tightness. Most often, the destruction occurs along the adhesive layer. A mathematical model is presented that takes into account the concentrated forces at the ends of the adhesive layer of a composite structure of the "metal-coating" type. Calculations of normal and tangential stresses are performed. The highest stress values in the polymer coating are obtained at the edge of the hole in the metal layer. As a result of the analysis, it was found that an increase in the overlap of the polymer coating of the hole contour and the distance from the hole contour lead to a significant decrease in stress values. The developed mathematical model and calculation algorithm allow calculating the stress-strain state of a metal structure with a hole and a polymer coating.

scholarly journals Mathematical model of the stress-strain state of a rod with an inhomogeneous layered structure

2021 ◽  
Vol 82 (4) ◽  
pp. 14-22
Author(s):  
S. M. Akhmetov ◽  
◽  
M. T. Userbayev ◽  
Zh. U. Iklasova ◽  
A. B. Bolatova ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Layered Structure ◽  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
Current State ◽  
Tension And Compression ◽  
The Difference ◽  
State Of Research ◽  
Wooden Structures

The stress-strain state (SSS) of a rod with an inhomogeneous layered structure is considered. On the basis of a brief review and analysis of the current state of research of rod systems, the relevance of the study of the SSS of layered-heterogeneous wooden structures is substantiated, taking into account the presence of different resistance of layers to tension and compression. On this basis, the authors solve the problem of determining the SSS of layered-heterogeneous wooden rods in creep conditions, where factors such as humidity and temperature, as well as the difference in the resistance of wood layers to stretching and compression are taken into account. When solving the problem, the mechanical-sorption creep of wood is also taken into account.

scholarly journals Visualization of the Stress-Strain State of Shell Structures Using Virtual and Augmented Reality Technologies

2020 ◽  
pp. paper13-1-paper13-12
Author(s):  
Alexey Semenov ◽  
Iurii Zgoda
Keyword(s):  
Mathematical Model ◽  
Thin Shell ◽  
Strain State ◽  
Interactive Visualization ◽  
Analysis Data ◽  
Shell Structures ◽  
Stress Strain ◽  
Heat Maps ◽  
Visualization Module ◽  
Stress Strain State

The paper describes a mathematical model of changes in the geometry of thin-shell structures for visualization of the analysis data on their stress-strain state (SSS). Based on this mathematical model, a visualization module for shell SSS visualization using VR and AR technologies was developed. The interactive visualization environment Unity 2019.3 and C# programming language were used. The interactive visualization module makes a 3D image of a shell structure and visualizes the SSS either through heat maps over the shell or through the changes in the shell geometry on the basis of the shell type, its geometric characteristics, and SSS analysis data (transferred to the visualization module by means of a JSON file). While working on the visualization module, the authors developed a system of components that makes it possible to visualize any 3D surface with coordinate axes (including numbers with a pitch determined automatically), visualize heat maps with a graduated scale, visualize a mesh over the graph to improve the perception of the surface deformations. The middle surface can also be deformed on the basis of SSS analysis data. This solution increases the efficiency of the work of specialists in civil engineering and architecture and can be used when training specialists in courses on thin-shell structures and procedural geometry.

scholarly journals Determination of the road surfaces stress-strain state by using of Global Navigation Satellite System

2019 ◽  
Vol 97 ◽  
pp. 04014
Author(s):  
Vitaly Baranchik ◽  
Anatoly Dotsenko
Keyword(s):  
Preventive Maintenance ◽  
Strain State ◽  
Base Stations ◽  
Intelligent Transport System ◽  
Navigation Satellite ◽  
Stress Strain ◽  
The Road ◽  
Stress Strain State ◽  
Repair Costs ◽  
Global Navigation

The reduction of the current road repair costs is possible to be ensured by reducing its labour intensity and increasing interrepair periods. To achieve these goals, it is proposed to create a system of the road planned preventive maintenance (RPPM) based on the automated road stress-strain state diagnostics with constant measurement of the surface deformation by using the GLONASS and GPS navigation satellite systems operating in real time mode. The RPPM system will be based on the Global Navigation Network of permanently operating base stations, which allow to continuously monitor the dynamics of changes in the stress-strain state of roads and effectively plan any repair works thereupon. A preliminary economic analysis showed that by using of permanent geonavigation base stations the road repair costs will be annually reduced by 18.57% for the first five years, and then by half in the following two years. In this case, the payback period will be 5.4 years. In order to adapt the existing geo-navigation control systems of road building machines to the Solution of the problem of road repairing it is necessary to make an appropriate experimental and design engineering development. The use of satellite measurements in the diagnosis of road conditions is the basis of the system of preventive maintenance in the road sector and the stage of development of the domestic intelligent transport system.

scholarly journals MATHEMATICAL MODEL OF THE SOIL STRESS-STRAIN STATE IN THE PROCESS OF ITS INTERACTION WITH THE WORKING BODIES OF THE DIGGING MACHINE

2019 ◽  
Vol 9 (2) ◽  
pp. 157-163
Author(s):  
Ольга Дорняк ◽  
Olga Dornyak ◽  
Михаил Драпалюк ◽  
Mikhail Drapalyuk ◽  
Игорь Казаков ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Strain State ◽  
Stress Strain ◽  
Stress Strain State ◽  
Soil Stress ◽  
Working Bodies
Sign in / Sign up

Export Citation Format

Share Document