Bazhenov, V. A.Pogorelova, O. S.Postnikova, T. G.2024-03-202024-03-202020Bazhenov V. A. Creation of mathematical model of platformvibrator with shock, designed for concrete products compaction and molding / V. A. Bazhenov, O. S. Pogorelova, T. G. Postnikova // Опір матеріалів і теорія споруд : зб. наук. праць / Київ. нац. ун-т буд-ва і архіт. ; гол. ред. П. П. Лізунов. - Київ : КНУБА, 2020. - Вип. 204. - С. 103 - 116. - Бібліогр. : 13 назв.2410-2547https://repositary.knuba.edu.ua/handle/123456789/12699Platform-vibrators are the main molding equipment in the production of precast concrete elements. Shock-vibration technology for the precast concrete production on low-frequency resonant platform-vibrators significantly improves the quality of the products front surfaces and the degree of their factory readiness. This technology is used to produce large elements. We describe the creation of a mathematical model for platform-vibrator that uses shock to produce asymmetric oscillations. The values of the upper and lower accelerations of the mold with concrete have different values with shock-vibration technology. The created mathematical model corresponds to the two-body 2-DOF vibro-impact system. It is strongly nonlinear non-smooth discontinuous system. It has some peculiar properties, namely: the upper body with very large mass breaks away from the lower body during vibrational motion; both bodies move separately; the upper body falls down onto the soft constraint; the impact that occurs is soft one due to the softness and flexibility of the constraint. The soft impact simulation requires special discussion. In this paper, we simulate a soft impact by a nonlinear contact force in accordance with the Hertz quasistatic contact law. The numerical parameters for this system were chosen in such a way that: firstly they provide the fulfillment of requirements for real machine, and secondly they allow analyzing its dynamic behavior by nonlinear dynamics tools. The created model is well enough to fulfill a number of requirements, namely: T-periodic steady-state movement after passing the transient process; the appropriate value of mold oscillations amplitude; the satisfactory value of the asymmetry coefficient that is the ratio of lower acceleration to the upper acceleration. We believe that the created model meets all the necessary requirements.enударно-вібраційний майданчиквібро-ударна системаформа з бетономверхнє та нижнє прискоренняplatform-vibratorshockvibro-impactmold with concreteupper and lower accelerationsArticle