Anchor bolts are commonly used in the construction industry. You might have already encountered them after walking past an ongoing construction project. For contractors, choosing the right type of bolt can make or break a concrete structure’s integrity and strength. Here’s what you need to know about it.

How Does an Anchor Bolt Work?

An anchor bolt is a type of heavy-duty fastener designed to attach objects to concrete or its surface. For instance, you need to mount steel poles on a concrete surface. Instead of drilling a hole to install the pole, using anchor bolts to connect it to the concrete is a faster, more efficient way. Embedding one end into the concrete offers stability and security by transferring the load to the surrounding area.

What Are Its Different Types & Why Do You Need Them?

Anchor bolts generally come in two forms—cast-in-place and post-installed. For the former, you have to drill a hole in the concrete to position the anchor bolt’s end. Pouring in wet concrete fills the space and prevents budging after hardening. Post-installed, on the other hand, don’t need casting to keep them in place. After being drilled inside, they compress first then expand mechanically. Some use epoxy or adhesives to impede unnecessary movement.

Apart from installation methods, anchor bolts also differ according to design, which affects their structural application.

• L-Shaped: An L-shaped or 90-degree design has a threaded end for the nut and washer to support an external load, while the bent portion creates resistance that prevents it from pulling out quickly. Its common applications include the installation of light poles and signage, as well as support for tooling and heavy equipment.

• Double End Rods With Plates: This variety is a straight rod with threads on both ends where a plate washer is added and either welded or tack welded to a concrete-embedded nut. It’s often used in structural columns and highway signage and sometimes bent for stronger fastening.

• Headed Anchor Bolt: This has a forged hexagonal, heavy hex, or square head on its non-threaded end, dissimilar to L-shaped bolts and anchor rods. By embedding the headed end, it can secure structures such as bridge rails, light poles, and steel columns.  

• Swedge Rods: Often used for highway work to connect piers, girders, and bridge bearings, a swedge anchor rod has multiple dimples or indentations for better resistance against sudden pullout. It contains a threaded end that protrudes when entrenched in concrete.  

For premium quality anchor bolts, contact Politte Ready Mix in Potosi, MO. They carry an extensive selection of construction materials, including snap tires, wire mesh, rebar, and concrete tubes. They also offer ready mixed concrete, sand, and gravel to contractors and residents throughout Washington County. Call (573) 438-5417 for more information or contact them via their website.