THE SYSTEM OF EXTERNAL REINFORCEMENT OF REINFORCED CONCRETE BENDING ELEMENTS AND MODELINGT HER WORK

Abstract

Strengthening of reinforced concrete elements such as beams and slabs is widely used in construction practice. In recent years, reinforcement application has increased due to a significant increase in the share of reconstruction in construction. This is the result of changes in stress, physical deterioration of existing buildings because of their poor maintenance and other factors, which leads to bearing capacity loss; that is why structures need to be strengthened to ensure sufficient performance under normal maintenance and reliability.

The variety of methods mentioned can be divided into 3 groups: strengthening with a change in the constructive and design scheme of a reinforced concrete member; strengthening without changing the work pattern of structures by building up their cross-sections with additional external reinforcement; strengthening by prestressing beams with horizontal ties.

Tie bars can be of three types - horizontal, sprengel and combined ones. When applying prestressed tie bars, the strengthened elements change their original constructive scheme because they turn into a combined system. Due to this, conventional bending elements are compressed noncentrally, and at their supports additional bending moments are created, which in turn influence the initial span moments. In this case, in all the variants of reinforcing beams with tie bars there are still significant reserves of increasing their carrying capacity.

The results of  analysis behavior under the load of bended reinforced concrete elements reinforced by a self-regulating tightening with a conventional beam are given and the mathematical model of the amplification system calculation is considered.