Центральноукраїнський науковий вісник. Технічні науки. Випуск 5. Частина 1. - 2022
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Item Експериментальне дослідження універсальної будівельної вібромашини широкого застосування(ЦНТУ, 2022) Яцун, В. В.; Яцун, В. В.; Данілов, В. Ю.; Yatsun, V.; Yatsun, V.; Danilov, V.В роботі проведені експериментальні дослідження працездатності способу збудження резонансних вібрацій пасивними автобалансирами для одномасної вібромашини з поступальним прямолінійним рухом віброплатформи. В результаті експериментальних досліджень встановлено, що у порівнянні зі звичайною інерційною вібромашиною нова машина має на 15-25% більшу продуктивність при меншому на 10-40% споживанні енергії. При цьому дебалансні маси у новому віброзбуднику менші у 4-6 разів дебалансних мас у звичайному інерційному віброзбуднику. Experimental studies of the efficiency of the method of excitation of resonant vibrations by passive autobalancers for a single-mass vibrating machine with translational rectilinear motion of the vibrating platform have been carried out. A vibrating machine with a platform size of 1000x600 mm has been designed, in which a ball balancer is used as a vibrating exciter. The vibrating machine can work in 2 two modes: the first - a vibrating sieve; the second is a vibrating table. The difference between the modes is the different amplitudes and frequencies of the working surface. According to the technical recommendations, Solidworks CAD created a 3D model of a single-mass vibrating machine with a vibrating exciter in the form of a ball autobalancer using the Cosmos Motion module. After checking the performance of the created 3D model, the optimal parameters were selected and an industrial design of the vibrating machine (an exact copy of the 3D model) was created. Before the experiments, a dynamic balancing of the shaft with the autobalancer assembly without balls in their own supports was performed. After checking the quality of balancing, the straightness of the platform was checked. Balls in the autobalancer were removed. 4 checkpoints were applied to the working surface of the platform. An electric motor with a speed of 25 Hz was started. Then with the help of the device "Beam 4" at each point simultaneously measured the value of vibration velocities. As a result of checking the straightness of the platform, it was found that the difference between the values of measurements at different points does not exceed 25%. This indicates the straightness of the movement of all points of the working surface of the platform and, accordingly, the sieve. An electric motor with a speed of 50 Hz was started. Using a vibrometer "Walcom" WM6360 were measured values of movement of the working surface of the table. Then the selection of the unbalanced mass was performed at which the oscillation range of the platform corresponded to the standard values of industrial vibrating machines. Then the platform was loaded with a load of 25 kg, 55 kg and the experiment was repeated. A series of experiments to determine the main characteristics of the developed design of the vibrating machine in the mode of vibrating table and vibrating screen. The energy efficiency of the proposed design of the vibrator was also tested. Measurements of electric energy consumption at different speeds and with different vibrators are performed. As a result of experimental studies, it was found that compared to a conventional inertial vibrating machine, the new machine has 15-25% higher productivity with 10-40% lower energy consumption. The unbalanced masses in the new vibrator are 4-6 times less than the unbalanced masses in the conventional inertial vibrator.Item Порівняння методів розрахунку плитних фундаментів з урахуванням результатів інженерно-геологічних вишукувань та геодезичних спостережень за процесом просідання(ЦНТУ, 2022) Пашинський, В. А.; Тихий, А. А.; Пашинський, М. В.; Карпушин, С. О.; Яцун, В. В.; Pashynskyi, V.; Tykhyi, A.; Pashynskyi, M.; Karpushyn, S.; Yatsun, V.На прикладі фундаменту під силос зерносховища у вигляді круглої залізобетонної плити діаметром 20,4 м виконане порівняння трьох методів розрахунку осідання суцільних плитних фундаментів. Розрахунки за моделлю плити на пружній основі та за моделлю об'ємних скінченних елементів дали середні значення осідання 2,15 см та 2,4 см, близькі до фактичної величини 1,75 см, отриманої за результатами натурних геодезичних спостережень, що велися з початку будівництва об'єкту. Регламентований чинними нормами проектування розрахунок за методом пошарового підсумовування дав різко завищений результат 13,7 см. Increasing the height of buildings and structures in combination with the development of areas with unfavorable geotechnical conditions cause the use of foundations in the form of solid reinforced concrete slabs. In complex geotechnical conditions and under high loads, the soils can work beyond linear deformation. This necessitates the calculation of the system "building-foundation-soil" based on the assumptions of nonlinear soil mechanics. The issue of designing foundations for cylindrical structures of the agro-industrial complex, in particular granaries, is especially relevant. The task of this study is a comparative analysis of different methods for calculating the subsidence of slab foundations to select a rational model of deformation of the soil. The comparison of calculation methods is carried out on the example of the foundation under the granary with a volume of 8841 m3. The foundation is made in the form of a round reinforced concrete slab with a diameter of 20.4 m. The characteristics of the soil are established by the results of geotechnical surveys. The calculation according to the Winkler model (elastic base plate with one coefficient of subgrade reaction) was performed in the "Cross" module of the SCAD Office software package. With a total load on the foundation of 2741 tf, its average subsidence is 2.15 cm. The calculation according to the model of three-dimensional finite elements of cubic shape was performed in the environment of the SCAD Office software package. The average subsidence of the foundation is 2.4 cm. The calculation by the method of layer-by-layer summation according to the instructions of DBN B.2.1-10: 2018 gave the subsidence of the foundation slab equal to 13.7 cm. The actual average subsidence of the foundation during the observation period in different areas of the foundation was 1.1… 2.4 cm and averaged 1.75 cm. The comparison of the analyzed methods for determining the subsidence of the foundation indicates the closeness of the results of calculations on the model of the slab on an elastic basis and the model of three-dimensional finite elements to the actual value of subsidence and the greatly higher result of the calculation by layer summation. The use of the latter method leads to excessive reliability in the design of foundations.