Types of Stirrups Used in Construction and Their Applications

Stirrups are the structural elements which help to provide support to the reinforced concrete beams and columns in the construction structures including buildings, bridges, and other structures. Stirrups can be made of steel and are able to resist tensile forces that have occurred in the construction structure. The stirrup can bent to a rectangular or U shape and can be placed vertically at fixed intervals. The structural integrity of the concrete elements can be ensured in case the space between the Stirrups does not exceed a certain limit. The size and shapes of the Stirrups depend upon the load-bearing capacity and other requirement of the construction structures.

The purposes of Stirrups

➢ The main purpose of Stirrups is to hold the primary reinforcement bars as well as prevent columns and beams from buckling.
➢ In addition, Stirrups are used to improve the comprehensive strength of the columns as well as increase the column’s ductility.

➢ Another purpose of using Stirrups is to inhibit the primary reinforcement movement during the concreting process of the construction structure.
➢ For the same purpose as in columns for the calculation of lumpsum, Stirrups have been employed in the beams.
➢ It is also used in producing the longitudinal bars along with the lateral confinements.
➢ This is also used to keep the longitudinal bars in place during the construction process.
➢ Stirrups are also used to keep the concrete in the core thus helping to make the concrete more ductile and strong.

Design and installation of Stirrups

The effectiveness of stirrups on the construction site depends upon the proper design and installation procedure. Several factors that should be considered while designing and installing Stirrups are:

Size

The size and diameter of stirrups should be selected on the basis of the structural requirements.

Spacing

There should be properly spaced between the Stirrups to provide adequate shear resistance.

Cover

Concrete cover helps to protect Stirrups from fire damage and corrosion.

Anchorage

Anchorage helps to ensure that Stirrups can develop their full strength.

Advantages of using Stirrups in construction sites

Stability improvement

Stirrup helps to keep the structure of the reinforced concrete at its desired shape and provides stability. This stability improvement helps to make the building structure resistant to outside forces.

Enhanced strength

With the help of Stirrups, the reinforced concrete can stay strong and stable under heavy loads. Additional strength has been provided by Stirrups which helps to prevent cracking and fragmentation of the building structures.

Improving the resistance of crack

With Stirrups, the reinforced concerts are resistant to cracks as Stirrups help to distribute the stress equally throughout the structure of the buildings. This stress distribution helps to prevent stress in the concreted areas that lead to cracking. This is also useful to keep the concrete in its shape which is less likely to crack.

Distribution of the load

Stirrup helps to distribute the loads of the building evenly throughout the building structure thus helping to reduce the stress concentrations.

Confinement of the concrete

Stirrup helps to confine the concrete core in columns which helps to enhance the comprehensive strength and ductility of the columns.

Durability

Stirrup helps to contribute to the long-term durability of the buildings by controlling the cracks and increasing the overall structural performance of the buildings.

Different types of Stirrups

There are various types of Stirrups which have different types of applications in construction sites. These types include:

Single-Legged Stirrups

This is the lightest type of stirrup which is used in low-intensity construction works.

These single-legged stirrups comprise one bar bent in a U-shape which is tied to the primary reinforcement bar. In the case of a building with less shear stress, this type of stirrups can be used.

Double-Legged Stirrups

This is the most common type of stirrup used in the construction works. This type of stirrup has been utilized for the construction of columns as well as the construction of beams due to having excellent shear resistance capacity.

Four-Legged Stirrups

This type of stirrup consists of four bends which helps to give additional resistance and strength to the shear forces. In the case of high-rise buildings or bridges where the loads are higher, these types of stirrups can be used.

Six-Legged Stirrups

This type of stirrup is used to support the eight-rod configurations. The extra rods in this six-legged stirrup help to provide additional support to the construction structure. The extra legs of this stirrup have been positioned between the two rods which are nearby.

Circular Stirrups

This type of stirrup is designed for circular or spiral columns which are used in bridges, foundations or in cylindrical structures.

In this case, the load of the construction structures are uniformly distributed which helps to provide resistance to the shear forces.

Helical Stirrups

This is also known as spiral stirrups which are similar to circular stirrups. Through these stirrups, better confinement and strength to the concrete have been added which helps to provide load-bearing capacity and flexibility to the columns.

To learn more, watch the following video tutorial.

Video Source: Civil Engineers

Torsion Stirrups

This type of stirrup is designed to resist the torsion forces and is applied in those structures which have the tendency to have heavy torsional loads including beams and slabs in industrial buildings.

Combined Stirrups

This is the hybrid version of some stirrup designs which involves multiple forces such as torsion forces, shear forces, and other axial forces. This type of stirrup helps to deliver maximum reinforcement. These combined stirrups are applied in industrial and infrastructure projects.