Determination of loads on the body of a boxcar with elastic elements in the center sill

The authors suggest elastic elements in the body of a centre sill being the basic carrying element of the frame to decrease the dynamic loads. This solution can transform the dynamic loads on the body into the work of the dry friction forces between the components of the centre sill. The authors substantiated the solution by means of mathematic modelling of the dynamic loads on the body of a boxcar in the vertical plane, including the bouncing oscillations. The differential equations of the motion were solved with the Runge–Kutta method under the zero initial conditions. This solution can decrease the accelerations on the body of a boxcar by about 20 % in comparison to that of the prototype car. The study presents the strength calculations and the design service life for the body of a boxcar. It was calculated that the design service life of a boxcar was longer than that of the prototype car by about 20 %. The research may be used by those who are concerned about higher efficiency of railway transportation

Studying the load of composite brake pads under high-temperature impact from the rolling surface of wheels

The object of the research is the processes of thermal stress, perception and redistribution of loads by the brake composite pad during braking of the car in operation. In the current conditions, wedge-dual wear of composite brake pads is observed in the braking systems of freight cars, the feature of which is the deterioration of the braking efficiency of freight trains. With this type of wear, both an increase in the load on the brake pad and an "underuse" of the amount of pressure on it can occur. A comprehensive thermal calculation was carried out for composite brake pads with uniform and wedge-dual wear. The results of the calculation showed that the amount of pressure on an abnormally worn pad is 23.3 % less than that acting on a pad with nominal values. It has been proven that the change in the pressure force on the composite pad with different values of the wear parameters during braking leads to a change in the braking force that occurs between the wheel and the rail during braking. The calculation of the strength of the composite brake pad with wedge-dual wear was carried out. The obtained results will make it possible to develop measures to modernize the elements of the brake lever transmission of freight cars. The field of practical use of the obtained results is car-building enterprises. The conditions for the practical use of the results are the brake lever transmissions of carriages of cars with a gauge of 1520 mm. The conducted studies prove the negative impact of wedge-dual wear not only on braking efficiency, but also on the strength of brake pads. This makes it necessary to create measures aimed at its elimination, which will contribute to increasing the level of train traffic safety and significantly reducing the operational costs of maintaining freight car

Influence of structural solutions of an improved brake cylinder of a freight car of railway transport on its load in operation

The object of research is the processes of occurrence, perception and redistribution of loads in the design of the car brake cylinder in operation. To compensate for angular shifts of the brake cylinder rod at its maximum exit from the housing, improvement measures are proposed. This improvement consists in the use of a safety element to limit the angular movements of the rod when leaving the body. The load of the brake cylinder rod during its angular displacements is determined. The condition for ensuring the strength of the rod is obtained. The optimal parameters of the pipe of the safety element (limiter) of the brake cylinder rod were determined by its allowable moment of resistance. For the possibility of moving the levers interacting with the stem, special windows are provided in the limiter. It is proposed to fix the limiter to the cover by welding. To determine the strength of the brake cylinder, a calculation was made using the finite element method. The results of a robust calculation showed that the maximum equivalent stresses occur in the brake cylinder cover and amount to 118.5 MPa. Therefore, the strength of the brake cylinder is ensured. A feature of the obtained results is that the proposed improvement can be applied not only at the stage of designing a brake cylinder, but also at the stage of modernization. The sphere of practical use of the obtained results is railway transport. The conditions for the practical use of the results are the absence of deformations of the brake cylinder rod. The research carried out will help to improve the efficiency of rolling stock brakes, ensure traffic safety, increase rolling stock speeds, deliver goods, etc. Also, the conducted research will contribute to the creation of developments to improve the reliability of the rolling stock brake

Integration of extended reality (XR) in non-native undergraduate programmes

This paper presents the use of XR technologies in teaching CAD. Immersive experience generated by XR technologies have traditionally found a quicker uptake in visualization industry especially in arts, entertainment and gaming. Current undergraduate (UG) modules in computer science and game development programme provide underpinning modules for learning XR technology. Other non-native UG Programmes such as architecture, engineering (mechanical, aerospace, automotive, Computer Aided Design (CAD)) and construction do not provide these modules as a part of the programme. However, use of XR technology has been widely exploited in such application areas as its use cases are exponentially growing. The proposed study explored the potential benefits of utilizing XR technology in the BSc CAD, BEng (Mechanical and Aircraft) program. The paper presents a review of the current state of the XR use in various industries and XR related pedagogy, followed by a pilot study of introducing Virtual Reality (VR) application to current programme modules at the University of the West of Scotland. This use case is particularly important to collaborative design review using XR technology. The study captures students' and staffs' perception on adapting to this new technology. This paper provides an academic feasibility scenario for integrating XR/VR subject area in non-native UG programmes. The paper also provides an use-case for implementing VR assisted collaborative product review for evaluating a product design and development progress

Визначення навантаженості довгобазної конструкції вагона-платформи з пружними елементами в повздовжніх балках

This paper reports a study into the dynamic loading and strength of an improved carrying structure of the platform car. A special feature of the car is the presence of elastic elements in the main longitudinal beams of the frame. This could improve the fatigue strength of the carrying structure of the platform car under operational modes. Mathematical modeling was carried out to determine the dynamic load on the carrying structure of the platform car. The fluctuations of bouncing were taken into consideration. It has been established that the vertical acceleration of the carrying structure of the platform car without cargo is about 2.0 m/s2 (0.2 g). In this case, the vertical accelerations that act on the carrying structure of the platform car are lower by 15 % as compared to the prototype wagon. The main indicators of strength of the bearing structure of the platform car have been determined. The calculation was carried out using a method of finite elements employing the software suite SolidWorks Simulation (France). When compiling the estimation scheme, it was taken into consideration that the carrying structure of the platform car was loaded with four containers the size of 1SS. In this case, the maximum equivalent stresses occur in the region of interaction between a pivot beam and spreads and are 254.0 MPa. That warrants the strength of the carrying structure of the platform car. The numerical values of acceleration of the carrying structure of the platform car have been determined, as well as the fields of their location, by applying computer simulation. The fatigue strength and oscillation eigenfrequencies in the carrying structure of the platform car have been investigated; their designed service time has been estimated. The reported research would contribute to building innovative structures of platform cars, as well as to improving the efficiency of combined transportation.Проведено исследование динамической нагруженности и прочности усовершенствованной несущей конструкции вагона-платформы. Особенностью вагона является наличие в основных продольных балках рамы упругих элементов. Это позволит повысить усталостную прочность несущей конструкции вагона-платформы при эксплуатационных режимах. Для определения динамической нагруженности несущей конструкции вагона-платформы проведено математическое моделирование. Ко вниманию приняты колебания подпрыгивания. Установлено, что вертикальные ускорения несущей конструкции вагона-платформы в порожнем состоянии составляют около 4,0 м/с2 (0,4g). При этом вертикальные ускорения, действующие на несущую конструкцию вагона-платформы ниже на 15% по сравнению с вагоном-прототипом. Определены основные показатели прочности несущей конструкции вагона-платформы. Расчет проведен по методу конечных элементов в программном комплексе SolidWorks Simulation (Франция). При составлении расчетной схемы учтено, что несущая конструкция вагона-платформы загружена четырьмя контейнерами типоразмера 1СС. Максимальные эквивалентные напряжения при этом возникают в зоне взаимодействия шкворневой балки с раскосами и составляют 254,0 МПа. То есть прочность несущей конструкции вагона-платформы обеспечивается. Определены численные значения ускорений несущей конструкции вагона-платформы и поля их дислокации путем компьютерного моделирования.   Исследованы усталостная прочность и собственные частоты колебаний несущей конструкции вагона-платформы, а также проектный срок ее службы. Проведенные исследования будут способствовать созданию инновационных конструкций вагонов-платформ, а также повышению эффективности эксплуатации комбинированных перевозокПроведено дослідження динамічної навантаженості та міцності удосконаленої несучої конструкції вагона-платформи. Особливістю вагона є наявність в основних повздовжніх балках рами пружних елементів. Це дозволить підвищити втомну міцність несучої конструкції вагона-платформи при експлуатаційних режимах. Для визначення динамічної навантаженості несучої конструкції вагона-платформи проведено математичне моделювання. До уваги прийняті коливання підскакування. Встановлено, що вертикальне прискорення несучої конструкції вагона-платформи у порожньому стані складає близько 2,0 м/с2 (0,2 g). При цьому вертикальні прискорення, які діють на несучу конструкцію вагона-платформи, нижчі на 15 % у порівнянні з вагоном-прототипом. Визначено основні показники міцності несучої конструкції вагона-платформи. Розрахунок проведений за методом скінчених елементів в програмному комплексі SolidWorks Simulation (Франція). При складанні розрахункової схеми враховано, що несуча конструкція вагона-платформи завантажена чотирма контейнерами типорозміру 1СС. Максимальні еквівалентні напруження при цьому виникають у зоні взаємодії шворневої балки з розкосами та складають 254,0 МПа. Тобто міцність несучої конструкції вагона-платформи забезпечується. Визначено чисельні значення прискорень несучої конструкції вагона-платформи та поля їх дислокації шляхом комп’ютерного моделювання. Досліджено втомну міцність та власні частоти коливань несучої конструкції вагона-платформи, а також розраховано проектний строк її служби. Проведені дослідження сприятимуть створенню інноваційних конструкцій вагонів-платформ, а також підвищенню ефективності експлуатації комбінованих перевезен

Determination of the loading on a hopper container transported by sea

The efficiency of freight transportation can be improved by the use of hopper containers. If required they can be equipped with lift-off roofs, which makes it possible to transport the freight requiring protection from weather. The possibility to transport these containers by sea was studied through. The research conducted will promote the designing of containers with better technical and operational characteristics that will improve the efficiency of container transportation

Experimental research into the stress-strain state of the center sill of a box wagon with filler

The loading on the bearing structures of wagons in operation can be reduced by applying closed profiles filled with energy-absorbing material in wagon frame components. The results of the research demonstrated that with filler in the rod the stresses were reduced by 5% in comparison with stresses in the rod without filler. The difference between the experimental and theoretical strength calculations for the rods was about 3%. The results obtained can be used by those concerned about the development of innovative structures of wagons with better operational characteristic

ВИЗНАЧЕННЯ ЧАСТОТ І ФОРМ ВІЛЬНИХ КОЛИВАНЬ ПІШОХІДНОГО МОСТА

In the paper the issues of obtaining the rational structure of statically indeterminate steel concrete trussed beam of a foot bridge are described. The tie rod insertion is very efficient in increasing of the structure’s carrying capacity, rigidity and (in many cases) economy.В настоящей работе излагаются вопросы рационализации конструкции статически неопределимой сталебетонной шпренгельной балки пешеходного моста. Включение шпренгеля в работу конструкций является эффективным способом повышения ее несущей способности, жесткости и, во многих случаях, экономичности. У роботі, що пропонується до розгляду, висвітлено питання раціоналізації конструкції статично невизначеної сталебетонної шпренгельної балки пішохідного моста. Включення шпренгеля в роботу балки є ефективним засобом для збільшення її несучої здатності, жорсткості та, у багатьох випадках, економічності

DEFINITION OF FREQUENCY AND FORMS OF FREE VIBRATIONS OF THE FOOTBRIDE

In the paper the issues of obtaining the rational structure of statically indeterminate steel concrete trussed beam of a foot bridge are described. The tie rod insertion is very efficient in increasing of the structure’s carrying capacity, rigidity and (in many cases) economy