Road-building Machines Research Articles

Evaluation of the Operational Properties of the Adhesive—Melts Used during Repair of the Cooling Systems of Road-Building Machines

Results of strength (static and dynamic) tests of the adhesive—melts, data on their resistance under the long-term effect of water, oil, and antifreeze, as well as results of the structural analysis after the action of the investigated aggressive media, are presented. It was found that the adhesive—melts possess satisfactory resistance to water and antifreeze, as well as good resistance to semisynthetic oils. Evaluation of the strength of the adhesive—melts under dynamic conditions showed that the losses of strength after 10 days of holding in a vibration test rig did not exceed 1% for Teplax adhesive-melt and 1.8% for Letex adhesive.

•Оценка эксплуатационных свойств клеев-расплавов, используемых при ремонте систем охлаждения дорожно-строительных машин

•Оценка эксплуатационных свойств клеев-расплавов, используемых при ремонте систем охлаждения дорожно-строительных машин

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

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.

Service Properties of the Thermoplastic Polymer Materials Used for Repairing Road-Building Machines

The service properties of thermoplastic materials (molten adhesives) are studied to estimate the possibility of their application for repairing road-building machines. The swelling resistance of molten adhesives in working media, namely, water, motor oil, and antifreeze, is investigated. Dynamomechanical analysis is used to analyze the deformation properties of the molten adhesives. The adhesion strengths of the epoxy adhesives traditionally used in repairing machines and the thermoplastic molten adhesives are compared.

Effective equipment and technology for building highways

Modern road building machines at a high level of mechanization do not meet the increased quality indicators of building highways. One of the main reasons for such poor quality is the lack of compaction of all the structural layers of the road pavement. The existing technology of compacting road-building materials is based on compression deformations, a significant portion of the air remains in the volume of the compacted material and leads to the formation of uneven surfaces (wheel tracks, transverse waves). The new technology of the compaction of road-building materials is based on shear deformations and compression deformation, thus creating a dense, rigid and unchangeable material structure. The article considers the peculiarities of the technology of laying road-building materials and proposes a technical solution for obtaining high-density structures from composite materials. It presents a comparison of the existing and the new technology of compacting road-building materials. The technical solutions of the new devices of the machines’ working elements (new equipment and technology) provide a higher coefficient of compaction for various road-building materials.

Vehicle reliability and safety through simulation of the sequence of restoration of motor vehicle components

Abstract Road-building machines are high-tech equipment operating in special conditions related to particular characteristics of construction. Consequently, they are subject to specific requirements. This article pays attention to safety of road-building machines. Emphasis is placed on the sphere of safety of road-building machines, such as the broken part factor, the consequences of which create hazardous and harmful factors for people. Failure and breakdown of a part depend on the manufacturing and restoration technology of the part. It is established that most parts of road-building machines that go into breakdown are shaft-type parts. A new approach is proposed to optimize the very technology of restoration of road-building machine part. The paper sets forth main approaches of the zoning method under the principle of maintaining the hierarchic relation of probabilities of possible environmental conditions. As a result, it was revealed that the highest efficiency of the restoration workflow process of shaft-type parts of road-building machines can be achieved through integration of the zoning method under the principle of maintaining the relation of probabilities of possible conditions of the research environment into solution of the dynamic programming problem during determination of the optimal transition pattern of a part during restoration.

Восстановление деталей дорожно-строительных машин моделированием в многокритериальной постановке с применением коэффициентов относительной важности

Восстановление деталей дорожно-строительных машин моделированием в многокритериальной постановке с применением коэффициентов относительной важности

Оценка методов восстановления деталей дорожно-строительных машин в многокритериальной постановке

Оценка методов восстановления деталей дорожно-строительных машин в многокритериальной постановке

Application of hydraulic device as working bodies of the road-building machines

Application of hydraulic device as working bodies of the road-building machines

МНОГОМАСШТАБНОЕ МОДЕЛИРОВАНИЕ И АНАЛИЗ МЕХАНИЗМА ВОЗНИКНОВЕНИЯ ТЕХНОЛОГИЧЕСКИХ МЕЖСЛОЙНЫХ НАПРЯЖЕНИЙ В ТОЛСТОСТЕННЫХ КОЛЬЦАХ ИЗ СТЕКЛОПЛАСТИКА

Thick-walled GFRP rings are widely used in high-loaded friction units of working elements of road-building machines as sliding bearings. They must endure high radial loads and work in the condition of a limited lubrication by using the lubricant which is located only in the open pores of the bushing. In large structures of sliding bearings (bearing elements of road-building machines) the thickness of a bushing might be dozens of millimeters. The reality is that it is necessary to use bushings with a rather big thickness to reduce the dynamic load for road-building machines. However, if the thickness of a composite ring increases, it often results in the inter-laminar failure which is caused by high technological (inter-layer) and stretching stresses due to the anisotropic thermal expansion and shrinkage of fabric composites. Furthermore, these stresses can also cause a significant distortion of a thick-walled GFRP ring after machining. In this work, it is assumed that the tension winding of the pre-impregnated fabric on a rigid mandrel leads to a heterogeneous compression of the internal layers and a distortion of the original composite woven structure through the thickness. The threads of the inner layers are curved more than the threads of the outer layers. For this reason, the coefficients of thermal expansion (CTE) of the inner layers happen to be larger than the CTE of the outer layers. Irregular distribution of the CTE gives rise to residual tensile stresses in the transverse (radial) direction. This paper presents the results of dilatometric studies of distributing of the CTE in the thickness of the hoop and axial directions. To determine the volume fraction of filaments and matrix into the threads of GFRP, we used the burn-out method. The observation of slices in the optical microscope allowed us to determine the degree of the curvature of fibres and the thickening of inner ring layers for further 3D modelling. The structure of the woven composite ring was modelled by using impregnated unidirectional (UD microplastic) threads and repeated unit cell. Modulus of elasticity, Poisson's ratios and coefficients of thermal expansion at microscale, macroscale and mesoscale were calculated by FEA (ANSYS Workbench). Thermomechanical properties were used to evaluate the residual technological interlayer stresses in the GFRP sliding bearing busing at the macroscale.

Conceptual Designing of Mould Board’s Surface by Geometrical Modeling

In article are considering design-projects of: conceptual mould-board of plough, with decision of task in view by a combination of several constructions; conceptual model of mould-board, with functional useable variations in several agricultural, meliorative and road-building machines; construction of plough’s mould-board, with concept selection method by several criteria’s. The problems are executed by using constructive geometrical modeling methods, industrial design principles and CAD technologies.

Оптимизация восстановления деталей дорожно-строительных машин с использованием метода районирования

Оптимизация восстановления деталей дорожно-строительных машин с использованием метода районирования

METHODS OF INVESTIGATION AND SIMULATION OF HYDROPNEUMEROUS MECHANISMS APPLIED IN THE DESTRUCTION OF FROZEN AND SCALING SOILS BY MINING AND CONSTRUCTION MACHINES

The article contains information on the identification of the main directions in the study and design of hydraulic shock mechanisms used in the destruction of strong and rocky soils by mining and construction machines. The program and algorithm for calculating and modeling the basic parameters of hammers are presented, and also the dependencies of the parameters of hydrostatic devices used as working bodies of road-building machines are given, depending on the parameters of the developed soil and the parameters of the base machine built in the Maple program.

Management concepts of mobile road-builder machinery

The work objective is to define the properties of the mobile road-building machinery (MRBM) traffic flows for the control effectiveness improvement. The results of the system analysis of the MRBM control tasks are presented. Their solution concept is presented; the traffic control problem formalization for the mobile road-building machines under the ever-changing conditions of movement is performed. For the first time, system and structural status assessment criteria for MRBM are formulated; the control concepts of the mobile objects groups are analyzed; recommendations for selecting the type of control are given. Mathematical models of the traffic flows establishing the dependence of the motion speed on the traffic density, and a mathematical model of the traffic route optimization for the mobile road-building machinery are presented. Strategies of the adaptive and intelligent control of the mobile objects groups of different numbers, as well as the results of the regression analysis of the mobility objects motion model are presented.

ОСОБЕННОСТИ УСЛОВИЙ ЭКСПЛУАТАЦИИ РАБОЧИХ ОРГАНОВ СТРОИТЕЛЬНО-ДОРОЖНЫХ МАШИН И ФАКТОРЫ, ВЛИЯЮЩИЕ НА ИХ РЕСУРС

The article considers the peculiarities of the conditions of the working bod-ies of road-building machines that determine their reliability and durability

THE INFLUENCE OF OXIDATION ON TRIBOLOGICAL PROPERTIES OF RAPESEED OIL / OKSIDACIJOS ĮTAKA RAPSŲ ALIEJAUS TRIBOLOGINĖMS SAVYBĖMS / ВЛИЯНИЕ ОКСИДАЦИИ РАПСОВОГО МАСЛА НА ЕГО ТРИБОЛОГИЧЕСКИЕ СВОЙСТВА

Approximately a half of all consumed lubricants, in one or another way, end up in the environment. Some countries put forward recommendations or even requirements for the use of environmentally friendly bio-lubricants the purpose of which is to reduce a negative influence of lubricants. The priority areas of using environmentally friendly lubricants cover water transport, hydraulic systems in forestry machinery, railway applications, road building machines etc. Particularly it is the case when an increased possibility of putting a lubricant in the environment occurs. Regarding good lubricity and excellent biodegradability, vegetable oils are widely used as environmentally friendly lubricants. The biggest disadvantage of vegetable oils as base stock for lubricants is pure oxidation stability. This article deals with the influence of thermal oxidation on tribological properties of rapeseed oil. The obtained results show that oxidation decreases lubrication ability due to structural changes in oil. The greatest negative influence of oxidation is obtained at the end of the induction period. Santrauka Gerai žinomas faktas, jog apie pusė visų šiuo metu naudojamų alyvų vienokiu ar kitokiu būdu patenka į aplinką. Siekiant sumažinti tepamųjų medžiagų neigiamą įtaką aplinkai, tam tikrose srityse rekomenduojama, o kai kuriose šalyse net reikalaujama naudoti aplinkai nekenkiančias biologines tepamąsias medžiagas. Susidaro didesnė galimybė šioms medžiagoms tiesiogiai patekti į aplinką ir prioritetinėmis šių medžiagų naudojimo sritimis yra laikomas vandens transportas, miškų ūkio mašinų hidraulinės sistemos, geležinkelio mechanizmai, kelių tiesimo mašinos ir kt. Dėl gerų tepamųjų savybių ir gero biologinio suirstamumo augaliniai aliejai yra gana plačiai naudojami gaminant aplinkai nekenkiančias alyvas. Didžiausias tokių bazinių tepamųjų medžiagų trūkumas yra palyginti mažas atsparumas oksidacijai. Šiame straipsnyje nagrinėjama rapsų aliejaus oksidacijos įtaka jo tribologinėms savybėms. Gauti rezultatai rodo, jog aliejaus oksidacija dėl jame vykstančių struktūrinių pokyčių padidina trinties nuostolius ir paviršių nusidėvėjimą, didžiausią įtaką šiems parametrams darydama pasibaigus alyvos oksidacijos indukciniam periodui. Резюме Хорошо известен факт, что около половины применяемого масла попадает в окружающую среду. С целью сократить вред, наносимый окружающей среде от этих выбросов, рекомендуется, а в некото рых странах и требуется применение в некоторых областях биологических смазочных материалов. Приоритетными областями для применения этих материалов являются водный транспорт, гидравлические системы машин лесного хозяйства, механизмы железной дороги, машины для строительства дорог и др., т. е. те, в которых имеется повышенная возможность попадания смазочных материалов в окружающую среду. Растительные масла из-за хороших смазочных свойств и быстрого биологического распада широко применяются при производстве биологических масел. Наибольшим недостатком таких базовых масел является их относительно небольшая стойкость к оксидации. В представляемой статье приведены результаты исследований влияния оксидации рапсового масла на его трибологические свойства. Полученные результаты показывают, что оксидация масла из-за происходящих в нем структурных изменений увеличивает потери на трение и изнашивание поверхности, наибольшее влияние проявляется при окончании индукционного периода оксидации масла.

Repair of construction and road-building machines during construction of the Dnepr-donbass canal

Repair of construction and road-building machines during construction of the Dnepr-donbass canal