Abstract
At present oil and petroleum products are one of the main fuels in the world and a major source of income for many countries' budgets. It is clear that significant resources will be devoted to the restoration of the bearing capacity of existing steel cylindrical tanks. In this connection, they are considered to be particularly responsible structures, the design and construction of which should be based on strictly justified scientific provisions and technically possible, fundamentally new constructive developments, as well as optimal and cost-effective design solutions. One of such solution is prestress. Taking into account this fact, the aim of this work is a comprehensive study of seismic resistance of vertical steel tanks with the application of prestress method. It was found that the frequency of oscillations increases from 8.5% to 24.9% with an increase in the level of liquid filling, respectively with an increase in the hydrostatic pressure on the tank wall, as a result of theoretical research in the ANSYS software complex. Compared to the container without winding, the frequency of prestress container oscillation is significantly reduced regardless of the level of liquid filling in the container. Furthermore, the experimental study results of without winding tank oscillations frequency depending on the winding step and liquid filling level in the tank decreased by 6% to 18% compared with tank without winding. The results of the analysis of the experimental results show a satisfactory convergence between the values of frequencies (ranging from 1.5% to 10.1%) obtained in the design experiment and the tests of models of tank without winding and prestress winding tank. This fact indicates the reliability of the selected calculation models and obtained by theoretical value of frequency oscillations, and also justifies the proposed method of engineering calculation of frequencies and forms of oscillations of prestress winding tank