Results of the study of vibrations of concrete structures of the hydropower plant building

Abstract

The paper considers the results of studying vibrations of certain components of the hydropower plant building and their influence on the structure of the building as a whole. Vibration loads on various elements of the hydropower plant building which can cause damage to the building, thereby reducing the operational reliability of the whole structure and doing potential harm to the environment and human life support, is analyzed. The necessity for vibration monitoring of structures which should be conducted constantly or periodically to determine the present condition of structures is reasoned. Vibrations of the section concrete parts and vibrations of hydroelectric power plant units are considered. To detect the vibrational movements of the section as a solid body on an elastic base Section № 2of the hydropower plant building has been chosen. The recording of vibrations has been conducted for all three components: Z (vertical), H II (horizontal, parallel to the flow) and H ⊥ (horizontal, perpendicular to the flow) and the obtained data are given in this paper. The intervals of observed and dominant periods of vibrations are estimated. The research provides the data on amplitudes and accelerations of vibrations, as well as on the maximum recorded peak-to-peak swing. Based on the analysis of the received vibrograms, it is stated that the recorded vibrations are non-periodic and have a relatively narrow range of periods. In conclusion it is underlined that in order to determine the maximum possible amplitudes of section vibrations as well as to calculate the corresponding dynamic stresses in ceiling trusses it is necessary to observe vibrations when hydraulic units are operated simultaneously and the flow passes through the fully open bottom spillways of the inspected section.