INVESTIGATION OF THE EFFECT OF CLAPS ON THE STRESS-STRAIN STATE OF TANK STRUCTURES

Abstract

The need to study the problems of reliable operation of the reservoir system is relevant. Special attention should be paid to the specifics of the operation of oil storage tanks and their equipment. The Russian tank farm was formed in the 1970s, a significant part of it has a service life of more than 50 years. The experience of examining such structures with a long service life indicates the presence, in most cases, of the physical aging of their structural elements. The article presents the results of processing a cloud of points created using a ground laser scanner to determine the actual geometric deviations of the reservoir and their combined effect on the reliability of the reservoir. During the survey, a method of work was used that differs from the standard. In the field, a laser scanner was used instead of a theodolite; in office processing, software systems were used that simplify the tasks. In the process of research in the 3DR software package, a triangulation mesh model was created from a cloud of points from a set of finite elements to identify defects located on the wall. The data obtained can be compared with previous and future survey results. Also, the model can be used to create a calculation scheme in PC LIRA 10. We set the actual characteristics of the tank wall to the finite elements (the thickness of the first belt is 12 mm, the next ones 10 mm). The main load combinations were applied to the tank. The calculations were carried out for a combination of loads, including the own weight of the structures, the pressure of the stored product and the overpressure in the gas space. Circular and equivalent stresses according to the 4 (energy) theory of strength were analyzed. The use of a laser scanner and software systems reduces labor costs for tank inspection, improves the quality of work performed, makes it possible to see the real surface of the tank and take into account defects in the aggregate. This method is of practical importance and is currently used by the Department of Inspection of Buildings and Structures.