Uses of Anchor Bolts of Various Types for Securing Structures

Bolts are essential fastener units that find a use in making huge machines or structures. It is used in the fabrication industry for giving stability to the structure. Here we discuss one prominent bolt - the anchor bolt. We use the anchor bolt to fasten non-structural and structural components to concrete. All anchor bolts need stiffeners and steel plates to function.

What is a J Bolt?

First type of anchor bolt is cast-in-place bolt. This is the simplest and strongest. For fastening a wall to concrete we make use of such a bolt called a J bolt. It is shaped like the letter J and has threadings on its non-curved portion. It has a nut and washer to fasten each element to concrete. You can get more details from the J Bolt Manufacturers.

Types of Anchor Bolts and Uses

Anchor bolts play an important role in giving stability to a structure. When cast-in-situ, the embedded part has a hex head, a forged flange, or a 90 degree bend. It finds a use in concrete-steel composite structure as shear connectors. This is also used to connect machines to concrete floors and buildings to their concrete foundations. The various types of cast-in-place anchor bolts are as follows:

Anchor channels: These channels are set into precast concrete channels. It may be a cold formed steel shape or a hot rolled one. A T-shaped screw is placed in it to transfer the load to the base material.
Lifting inserts: This is used in pre-stressed or plain RC beams. It finds use for lifting operations. The insert can be a threaded rod or a plain bolt.
Threaded sleeves: This is made of a tube with internal threads that gets fixed back into concrete.
Headed stud: It is a steel plate with headed studs that are welded on it.
For all these, the mechanical interlock mechanism provides the means of load transfer. The load transfer takes place through the contact area alone.

Post-installed Bolts in Structures

We can install post installed bolts after drilling through the concrete structures. We classify them according to what they do in the structure.

Mechanical expansion anchors: Here the force transfer is through friction interlock mechanism. This is guaranteed by mechanical expansion. We use two kinds of mechanical expansion anchors.
Displacement controlled: This has a conical expansion plug and an expansion sleeve. The sleeve is internally threaded to accept a threaded element.
Undercut anchors: Here the force transfer is through mechanical interlock. You can see this type of bolt at the website of the Anchor Bolt Manufacturers. The contact surface is created by drilling to bring the contact head in touch with the hole in the wall.
Bonded anchors: Binding organic materials are used here to provide the bond. Force transfer takes place through this bond. Threaded or ribbed rods can be used and we can experiment with the change in the local bond. In ribbed bars, the resistance of the ribs with the concrete whereas in threaded rods, it is mainly friction.
In the first instance of bolt heads, all were square heads. The shaft withstands rotation when torque is applied. Now, it has given way to hex heads.