Influence of quality on the stress-strain state of the road fence post assembly

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.

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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

Russian journal of transport engineering ◽

10.15862/14sats418 ◽

2018 ◽

Vol 5 (4) ◽

Cited By ~ 1

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.

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PREDICTION OF THE STRESS-STRAIN STATE OF A ROAD STRUCTURE WITH SHALLOW TRANSVERSE TUBULAR DRAINAGE

ScienceRise ◽

10.21303/2313-8416.2020.001396 ◽

2020 ◽

Vol 4 ◽

pp. 24-32

Author(s):

Olena Slavinska ◽

Andrii Bubela ◽

Oleksandr Davydenko

Keyword(s):

Strain State ◽

Research Result ◽

Experimental Studies ◽

The Body ◽

Innovative Technology ◽

Normal Stresses ◽

Stress Strain ◽

The Road ◽

Stress Strain State ◽

On The Road

The stress-strain state of a road structure with shallow tubular drainage, which is arranged on waterlogged sections of public highways, has been investigated. Three-dimensional models of the road structure with pipes made of various materials were built using the finite element method. Experimental studies on models were carried out for cases of normative and over-norm load on the basis of the SCAD Office software and calculation complex. The distribution of normal stresses, deformation values in the road structure and directly in the body of the tubular drain is obtained. The working conditions were determined and the expediency of using PVC pipes and concrete pipes on the road of III category was substantiated. Subject of research: stress-strain state of a road structure with shallow transverse tubular drainage. Investigated problem: determination of deformations in a road structure with tubular drains based on the distribution of normal stresses. Main scientific results: distribution of isopoles and isolines of normal stresses, deformation values in road structures with shallow transverse tubular drainage. The expediency of using the type of drainage pipes on waterlogged sections of roads under conditions of excess load has been determined. The area of practical use of the research result: design institutions and enterprises specializing in the road transport industry. An innovative technology product: stress and strain distribution in atypical road structures with tubular holes. Scope of application of the innovative technological product: for the design of atypical road structures with tubular holes on waterlogged road sections.

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RESEARCH OF INFLUENCE OF UNFINISHED CONSTRUCTION EXCAVATION ON STRESS-STRAIN STATE OF EXPLOITED BUILDING BEARING STRUCTURES

Building constructions. Theory and Practice ◽

10.32347/2522-4182.2.2018.3-12 ◽

2018 ◽

Vol 0 (2) ◽

pp. 3-12

Author(s):

A Banakh

Keyword(s):

Strain State ◽

Stress Strain ◽

Stress Strain State

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КОНСТРУКТИВНО-ТЕХНОЛОГІЧНІ ОСОБЛИВОСТІ ХВОСТО-ВИХ БАЛОК СІТЧАСТОГО ТИПУ З ПОЛІМЕРНИХ КОМПО-ЗИЦІЙНИХ МАТЕРІАЛІВ ВЕРТОЛЬОТІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ

Open Information and Computer Integrated Technologies ◽

10.32620/oikit.2020.88.02 ◽

2020 ◽

pp. 15-30

Author(s):

А. Г. Гребеников ◽

И. В. Малков ◽

В. А. Урбанович ◽

Н. И. Москаленко ◽

Д. С. Колодийчик

Keyword(s):

Finite Element ◽

Strain State ◽

Layer Structure ◽

Metal Structure ◽

Element Model ◽

Stress Strain ◽

Element Analysis ◽

Mesh Structure ◽

Stress Strain State ◽

Mesh Structures

The analysis of the design and technological features of the tail boom (ТB) of a helicopter made of polymer composite materials (PCM) is carried out.Three structural and technological concepts are distinguished - semi-monocoque (reinforced metal structure), monocoque (three-layer structure) and mesh-type structure. The high weight and economic efficiency of mesh structures is shown, which allows them to be used in aerospace engineering. The physicomechanical characteristics of the network structures are estimated and their uniqueness is shown. The use of mesh structures can reduce the weight of the product by a factor of two or more.The stress-strain state (SSS) of the proposed tail boom design is determined. The analysis of methods for calculating the characteristics of the total SSS of conical mesh shells is carried out. The design of the tail boom is presented, the design diagram of the tail boom of the transport category rotorcraft is developed. A finite element model was created using the Siemens NX 7.5 system. The calculation of the stress-strain state (SSS) of the HC of the helicopter was carried out on the basis of the developed structural scheme using the Advanced Simulation module of the Siemens NX 7.5 system. The main zones of probable fatigue failure of tail booms are determined. Finite Element Analysis (FEA) provides a theoretical basis for design decisions.Shown is the effect of the type of technological process selected for the production of the tail boom on the strength of the HB structure. The stability of the characteristics of the PCM tail boom largely depends on the extent to which its design is suitable for the use of mechanized and automated production processes.A method for the manufacture of a helicopter tail boom from PCM by the automated winding method is proposed. A variant of computer modeling of the tail boom of a mesh structure made of PCM is shown.The automated winding technology can be recommended for implementation in the design of the composite tail boom of the Mi-2 and Mi-8 helicopters.

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