EXPERIMENTAL STUDIES OF WELL CONNECTING RINGS

A methodology for conducting experimental studies of the bearing capacity and crack resistance of well rings is proposed. Reinforced concrete elements of annular cross-section are used in many engineering structures, such as wells for various purposes, pressure and non-pressure pipes, power line supports, water towers, etc. There are a number of problems in the production and operation of such reinforced concrete structures. First of all, these are technological problems that arise during the manufacture of products due to the difficulties of installing the annular spatial reinforcement frame in the design position. And at the operation stage, especially when it comes to wells, the main problem is crack resistance and the associated moisture resistance. An effective way to solve these problems is dispersed reinforcement of concrete with steel fiber. Assessment of this effectiveness requires additional research, primarily experimental. Such researches are very few, primarily aimed at studying well rings. A special power platform design was developed and manufactured for testing. It was established that the nature of the ring deformation under the action of a load uniformly distributed along its perimeter can be divided into three stages. At the first stage, up to the load level corresponding to the beginning of crack formation, a linear dependence of the deformation of concrete fibers is observed. The magnitudes of relative deformations are practically the same. At the next two stages of loading, a sharp change in the rate of growth of deformations occurs. The load of the second stage increases by 35%, while the deformations due to the opening of cracks increase by 1.3 times. At the third stage ‒ the stage of destruction ‒ the load decreases (falls) by 4%, and the deformations increase almost twice, again due to the opening of already existing cracks. The results of the study provide an opportunity for further assessment of the influence of dispersed reinforcement of concrete with steel fibers on the bearing capacity and crack resistance of well rings.