Presenting a Suitable Method for Protecting Electromagnetic Field on Rebars of RC Foundation
AbstractElectrical reactors used in the power industry are equipment that typically includes multiple coils, and a high electric current passes through to about a few kilo amperes. In accordance with the technical specifications, dimensions, structure and physical shape of the equipment, magnetic fields are formed around them. The magnetic field of this equipment can affect the steel structure of the foundation and its retaining reinforcement concrete structures and cause the induction of the voltage of the rotary and stray electrical currents in the rebar mesh and the heat losses and metal components of the reactor foundation. Mechanical stresses caused by generated heat in steel rebars can cause failure, cracks and reduction of reinforced concrete durability. In this research, the reinforced concrete foundation of Tyristor Controlled Reactors by exposed to a low-frequency magnetic field and a relatively large flux density is simulated and analyzed using the ANSYS Workbench software. The amount and distribution of temperature and mechanical stress in the foundation were obtained and the results of software output were compared with the scientific criteria of fraction and failure. Then, four methods were evaluated for constructing a reactor foundation include the use of fiber reinforced polymer rebars, the use of steel rebars by insulation of their contact points with electrical insulating materials, such as polyvinyl chloride, the use of non-magnetic rebar type 304 and the use of Fiber Concrete with cost criteria, time and quality. Based on the results, the method of using steel rebar along with insulating their contact points and considering the electrical and thermal clearance of the reactor is economically feasible and is applicable at a shorter time and is technically acceptable.