Anchor bolts are designed to attach structural elements to concrete. In our industry, anchor bolts are typically used to attach steel to concrete. One end is embedded into the concrete, while the opposite end is threaded to attach structural support. There are four main types of anchor bolts: L-shaped, double end rods with plate, headed, and swedge. Each type has their own uses, sizes, and advantages.

All anchor bolts are designed to connect objects to concrete, but the way in which they perform this task varies depending on the type. The most common type of anchor bolt is cast in place. It’s called “cast in place” because it’s literally cast with concrete. To install a cast in place anchor bolt, you first drill an appropriately sized hole into the concrete surface. Next, you position the bolt into the hole. Finally, you pour wet concrete into the remaining space. The wet concrete will naturally surround the bolt, and once it hardens, the anchor bolt shouldn’t budge.

There are also drilled in place anchor bolts. Also known as post-installed anchor bolts, they don’t require the use of wet concrete. You simply drill them into hardened concrete. How do drilled in place anchor bolts work exactly? Some drilled in place anchor bolts rely on the properties of mechanical expansion. When you drill them into concrete, they’ll compress and/or expand. Other types of drilled in place anchor bolts require the use of adhesives, such as epoxy, to stabilize and prevent movement.