Role of reinforcement in concrete structure

 

The important role of reinforcement in construction engineering is reflected through reinforced concrete.

 

 

Reinforced concrete is composed of two materials with different mechanical properties: reinforcement and concrete. We know that concrete is a kind of artificial stone. Its compressive strength is high, but its tensile strength is very low, while the tensile strength of reinforcement is very high. In order to make full use of the mechanical properties of materials, we add reinforcement in concrete to make them work together, so that the concrete mainly bears pressure and the reinforcement mainly bears tension, so as to meet the different requirements of engineering structures.

 

In engineering structures, there are many types of reinforced concrete structures, and their stress and function are also different, so the composition and function of reinforcement in the structure are also different.

 

(1) Composition and function of reinforcement in reinforced concrete beam. The reinforced concrete beam is mainly equipped with four kinds of reinforcement: longitudinal stress reinforcement, bending reinforcement, erection reinforcement and stirrup, as shown in Figure 2-1.

① Action of longitudinal stressed reinforcement. The function of longitudinal stressed reinforcement is to bear the tensile stress generated by external force in the beam, so this reinforcement should be placed on the tensile side of the beam
② The role of bent reinforcement. The bent reinforcement is formed by the bending of longitudinal stressed reinforcement. Its function is not only to bear the tensile stress generated by bending moment in the middle of the span, but also to bear the shear stress in the bent section near the support.

 

 

③ Function of erection reinforcement. The main function of the erection reinforcement is to fix the correct position of the reinforcement and form a reinforcement skeleton with a certain height. In addition, the erection reinforcement can also bear the stress caused by temperature change and concrete shrinkage to prevent cracks. This reinforcement is generally arranged on both sides of the edge of the compression area of the steel beam and parallel to the longitudinal stressed reinforcement.

 

(2) Composition and function of reinforcement in reinforced concrete slab. The reinforced concrete slab is mainly equipped with stress reinforcement, distribution reinforcement or erection reinforcement.

 

① Action of stressed reinforcement. The stressed reinforcement of the slab has the same function as the longitudinal stressed reinforcement of the beam, and mainly bears the tensile stress generated by the bending moment. It is usually arranged in the tensile area along the span direction of the slab.

② The role of distributed reinforcement or erection reinforcement the role of distributed reinforcement is to more effectively transfer the external force on the slab to the stressed reinforcement, prevent cracks caused by temperature change and concrete shrinkage, and fix the correct position of the stressed reinforcement.

 

 

(3) Composition and function of reinforcement in reinforced concrete column. Reinforced concrete column can be divided into axial compression column, compression column and eccentric compression column according to different action modes of external force. The column is equipped with symmetrical and longitudinal stressed reinforcement and stirrup.

 

 

① The function of the longitudinal stressed reinforcement is to bear the central load and the compressive stress in the section together with the concrete. When the column is subjected to the eccentric load, the longitudinal stressed reinforcement also bears the tensile stress caused by the eccentric load.

 

 

② The function of stirrup is to ensure the position of longitudinal stressed reinforcement, correctly prevent longitudinal stressed reinforcement from being pressed and bent, and improve the bearing capacity of columns. In columns and other compression members, stirrup is closed.

 

(4) Composition and function of reinforcement in reinforced concrete wall. According to the design requirements, single-layer or double-layer reinforcement mesh can be configured in reinforced concrete wall, which is mainly composed of tree reinforcement and transverse reinforcement. When double-layer reinforcement mesh is adopted, tie bars are also set between the two layers of reinforcement mesh, as shown in Figure 2-4

 

 

The function of vertical reinforcement is to bear the tensile stress caused by horizontal load on the wall, and the function of horizontal reinforcement is to fix the position of beam reinforcement and bear a certain shear force.