Природничі науки, математика, статистика

Permanent URI for this collection

https://dr.csbc.edu.ua/handle/123456789/44

Browse

Browsing Природничі науки, математика, статистика by Subject "FORESTRY, AGRICULTURAL SCIENCES and LANDSCAPE PLANNING::Area technology"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Development of technological principles of technical control of bus bodies during operation based on passive safety conditions
    (Державний університет "Житомирська політехніка", 2022) Рубан, Дмитро Петрович; Ruban, Dmytro; Крайник, Любомир Васильович; Kraynyk, Lubomyr; Рубан, Ганна Яківна; Ruban, Hanna; Грубель, Михайло Григорович; Hrubel, Mykhailo; Дужий, Роман Володимирович; Duzhyi, Roman; Бабарига, Андрій Святославович; Babaryha, Andrii
    The object of this study is the permissible limits of aging of bus bodies during operation and the formation of appropriate recommendations to control them based on the conditions of compliance of the body with passive safety rules. According to the current method, the new model of the bus is checked for compliance with passive safety by a destructive method. However, during operation, the physical and mechanical properties of the body deteriorate until the moment of non-compliance with the requirements of passive safety. Therefore, the principles of technical control of bus bodies under the conditions of passive safety by non-destructive methods, the implementation of which became possible during the operation of buses, have been developed. 3 implementation options have been proposed. In the first variant, visual control is complemented by a measuring tool – an ultrasonic thickness gauge for measuring the thickness of the frame pipes. This method has not previously been used in the certification of vehicles. The second option involves checking the mechanical properties during repairs on a breaking machine. It is proved that during the restoration repairs of buses, the endurance limit of the steel elements of the body frame is reduced by 1.14–3.33 times. In the third variant, the methodology for modeling and calculating the stressed-strained state of the body was improved based on the method of finite elements, taking into account the effects of corrosion and fatigue strength of the metal of the frame. When modeling, the deformation of the body racks exceeded the permissible values by 1.5–2.0 times. This non-destructive method makes it possible to check the bus for compliance with passive safety requirements during operation, which was previously impossible. The scope of practical application is the introduction of research results into the real practice of operating buses at the legislative level. The results are suitable for monitoring the technical condition of buses by non-destructive methods during operation.
  • Thumbnail Image
    Item
    Forecasting the Durability of Public Transport Bus Bodies Depending on Operating Conditions
    (ПП «ТЕХНОЛОГІЧНИЙ ЦЕНТР», 2021) Рубан, Дмитро Петрович; Ruban, Dmytro; Крайник, Любомир Васильович; Kraynyk, Lubomir; Рубан, Ганна Яківна; Ruban, Hanna; Сосик, Андрій Юрійович; Sosyk, Andrii; Сосик, Андрій Юрійович; Shcherbyna, Andriy; Щербина, Андрій Васильович; Dudarenko, Olga; Артюх, Олександр Миколайович; Artyukh, Alexander
    This paper addresses the issue related to forecasting the durability indicators of public transport buses under operational conditions. It has been established that when buses are operated to transport passengers the bus bodies wear at different intensities. During operation, the strength of the body frame weakens under the influence of corrosion in combination with sites of fatigue destruction. As it was established, the intensity of corrosion of the bus body depends on the number of residents in the city where the bus is operated. The earlier established dependences were taken into consideration; the current study has identified two conditional variants of corrosion evolution based on the number of inhabitants: up to 1 million and exceeding 1 million. The expediency of repairs and their impact on the bus passive safety has been analyzed. It was found that the elements of the body frame, without external characteristic damage, no longer meet the specified conditions of strength as a result of sign-alternating loads and during long-term operation. Determining the durability of the bus body was made possible through the construction of a mathematical model. The model’s adequacy was confirmed by road tests of the bus. The devised model describes the movement of the bus over a road surface with different micro profiles, with different corrosion penetration, different loading by passengers, and bus speeds. It was established that the reason for the evolution of structural corrosion is the influence of salt mixtures preventing the icing of roads, as well as ignoring the washing of buses after such trips. It is recommended to use new software for the in-depth study into this issue addressing the combination of various factors of destruction: cyclic loads at variable bus speeds and the corrosion progress. The study results could make it possible to predict a life cycle of the body frame under factors that correspond to actual operating conditions.
  • Thumbnail Image
    Item
    Вдосконалення системи технічного контролю та допуску до експлуатації автобусів громадського транспорту
    (Харківський національний автомобільно-дорожній університет, 2019) Рубан, Дмитро Петрович; Крайник, Любомир Васильович; Рубан, Ганна Яківна
    Проведено аналіз європейського обов’язкового технічного контролю (TÜV) та порівняно з технічним контролем в Україні. Встановлено, що чинне законодавство щодо обов’язкового технічного контролю в Україні потребує доопрацювання. Запропоновані доопрацювання дозволять підвищити пасивну безпеку автобусів та стимулюватимуть ефективне оновлення парку автобусів громадського транспорту України.
  • Thumbnail Image
    Item
    Оцінка впливу введення площадок низького входу «low-entry» в структуру несівного кузова на ресурсні характеристики автобуса в експлуатації
    (Харківський національний автомобільно-дорожній університет, 2018) Рубан, Дмитро Петрович; Крайник, Любомир Васильович; Рубан, Ганна Яківна
    Проведено оцінку впливу введення площадок низького входу в структуру несівного кузова на ресурсні характеристики автобуса. Наведено реальні приклади пошкоджень кузова та елементів підвіски. Запропоновано перегляд та уточнення граничних умов для розрахунку МКЕ каркасу кузова та вдосконалення структури та сортаменту труб.