Description: Using vibration or vibrocompression technology for manufacturing small concrete products (e.g. blocks, curbs, paving flagstones) is a promising field in contemporary civil engineering. The equipment which is necessary for manufacturing small concrete products is cheaper and occupies less space than the equipment used for manufacturing prefabricated reinforced concrete. It also requires less energy to produce one item of production. The design of vibration machines for molding concrete products is continuously improved due to more advanced structural details, automation of working processes, and wider technological capabilities. Considering the production of small concrete products, the promising trend is to use molding machines with low carrying capacity, equipped with a new type of drive that would allow easy adjustment of the parameters of vibration if the composition of the concrete mix is changed or when the range of the produced items is expanded. To satisfy these conditions, a new vibration machine with a pneumohydraulic drive was designed, the dynamics of its pneumomechanical system was modeled, and the most cost-effective modes of manufacturing concrete products were defined. The findings of the analytical and experimental research provide a scientific basis for the calculation of the vibration machine with a pneumohydraulic drive that allows comprehensive consideration of the vibration mode, the parameters of the pneumomechanical system, as well as the properties of the material (concrete mix). For the production of small-scale concrete products, it is promising to create the formation of small load-carrying devices with new versions of the drive, allowing to easily change the vibration parameters when changing the composition of the concrete mixture, as well as expanding the range of products. Such requirements correspond to low-frequency vibrating machines with pneumatic and pneumohydraulic actuators, for the creation of which it is necessary to solve the question of the dynamics of vibration systems of machines, assessing the impact of the characteristics of concrete mix on the working bodies and development of calculation methods.
Keywords: small concrete product molding, vibrating machines with pneumohydraulic drives, dynamic system modeling