Stirrup

Stirrup

The transverse reinforcement used in reinforced concrete columns and beams is called stirrups.

It is a thin bar or mesh reinforcement bent in the form of rectangle, square, polygon and circle depending on the cross-section of the element. Stirrup, first of all, is a necessary and indispensable element in the assembly and placement of the reinforcement cage to ensure its stability in wet concrete. The stirrup is also required to increase the local buckling strength of the bending reinforcement. When the stirrup is used at frequent intervals, it increases the bending strength as well as the shear strength of the reinforced concrete element by acting as a banding.

It gives the elements greater plastic deformability; Increases element and structure continuity. It is necessary to provide the shear and shear-bending strength of the reinforced concrete element. It is a very important element in preserving the integrity of the structure, especially in the stresses of the reinforced concrete section close to the final limit state. Most of the earthquake damage is caused either by the lack of stirrups or by faulty and incompletely arranged stirrups.

Benefits of using stirrups as shear reinforcement

• Since the oblique tensile stresses are distributed along the beam axis, stirrups placed regularly at regular intervals are suitable for countering the effect.
• Stirrups that make a certain angle with the oblique tensile stresses are also suitable when the sign of the shear force changes.
• By attaching the longitudinal reinforcement of the beam to the concrete, stirrups increase the rivet effect in meeting the shear force.
• Together with the concrete pressure forces that occur in meeting the shear force, they create a cage system effect.
• By limiting the cracks that occur due to oblique tensile stresses, they allow some of the shear force to be carried by aggregate friction.
• They increase both the strength and durability of the concrete by limiting the lateral deformation of the concrete, especially in the case of stirrups that are frequently used.