Vibrations in engineering systems

Abstract

The value of vibration, defined as the oscillatory phenomenon of a solid subjected to the action of force, appeared relatively recently. In fact, mechanical vibration became real only after the industrial revolution. Mechanical oscillatory phenomena, for example, due to working equipment and train movement, began to emerge only by the second half of the eighteenth century. The intensive use of new machines and mechanisms suddenly filled the world, until then, quiet and silent, with new intense noises and vibrations. Different ways of calculating the estimated oscillations of engineering structures, methods of reducing vibrations to the level allowed or their complete isolation, determine the purpose and main problems of the applied theory of mechanical vibrations. In engineering practice, we are almost always interested in predicting the response of a structure or mechanical system to an external effect. For example, we may need to predict the response of a bridge or high-rise building to wind loads, earthquakes, or ground motion. In mechanics and construction, resonant catastrophe describes the destruction of a building or a technical mechanism by induced vibrations at the resonant frequency of a system, which causes its oscillation. Periodic excitation optimally transfers vibration energy to the system and stores it there. Because of this repeated and additional energy input, the system sways more and more until its load limit is exceeded. Frequent reason for these disasters were periodic oscillations of bridges. Periodic fluctuations can be described as a body movement that regularly goes through an equilibrium position. Any oscillatory movement of a mechanical system relative to its equilibrium position is called vibration.