Ecological-Economic and Technical Advantages of Reinforced Concrete Girders with Combined Reinforcement

Don State Technical University, 344022 Sotsialisticheskaya str. 162, Rostov-on-Don, Russian Federation

^* Corresponding author: mailyan@rgsu.ru

Abstract

Changing of usual reinforcement, having, as a rule, welding joints with the pre-stressed joint-free steel has a significant ecological meaning, reducing harmful emissions. Decrease of the concrete consumption is also solving this important ecological issue, since the volume of concrete and concrete dust is reduced. In the compressed elements extreme compressing forces in the reinforcement upon concrete destruction reach 400-500 MPa due to limited concrete compression, which is why use of extra-strong reinforcement in such elements is not reasonable. With the purpose of increase of extreme compressing forces in the reinforcement of compressed elements it is suggested to pre-compress it. Increase of limits of stress in the reinforcement allows to efficiently using extra-strong reinforcement in the compressed zone which will lead to substantial reduction of its consumption. Effect from the pre-compression of the reinforcement is the higher, the bigger is the reinforcement percent. Degree of increase of strength of the elements upon pre-compression of reinforcement with decrease of concrete strength increases.