Types of Concrete Anchor Bolts
If you are searching for what type of concrete anchor bolt is the right fit for your job, you came to the right place. There are many types of anchor bolts that function differently and are designed for a wide variety of applications. Continue reading to learn about the different types of anchor bolts, common applications they are used for, and the factors to consider when choosing the correct bolt.
Article Contents:
What is an Anchor Bolt?
Anchor bolts are mechanical fasteners that attach and secure objects to concrete surfaces. One end of the anchor bolt is installed into the concrete and the other end is visible above the concrete. The end that is exposed is typically threaded for attaching equipment.
Anchor Bolt Uses
Anchor bolts are designed to make your life easier by securing structures in place. This includes structural and nonstructural equipment. These versatile bolts are used in many industries. Common applications include:
- Chemical, petrochemical, and oil & gas equipment supports
- Power and steel industry
- Construction industry
- Rail and aviation infrastructure
- Pharmaceutical and food processing plants
- Nuclear industry
Types of Anchor Bolts
Anchor bolts are categorized into two types:
- Cast-in-place anchor bolts: Set into wet concrete and cured in place. Common examples include L bolts and J bolts.
- Drop-in anchor bolts: Installed into pre-cured concrete using a drilled pilot hole. Common examples include wedge anchors and sleeve anchors.
1. Wedge Anchor Bolts
Wedge anchors are widely used for their strength, corrosion resistance, and ease of installation. They expand against the concrete when tightened, making them ideal for heavy loads and shear force applications. Available in zinc, galvanized, and stainless steel.
2. Drop-in Anchor Bolts
Drop-in anchors are female-style anchors that are placed into pre-drilled holes and set with a setting tool. Ideal for use with threaded rod to suspend equipment such as ductwork, cable trays, and fire sprinkler heads.
3. L Bolts and J Bolts
L bolts and J bolts are bent-bar anchor bolts set into wet concrete. Commonly used for structural applications such as signposts, shafts, heavy hardware, and tooling. They’re designed to be used with compatible nuts and washers.
4. Sleeve Anchor Bolts
Sleeve anchors consist of a threaded bolt with an expander sleeve. When the nut is tightened, the sleeve expands to grip the concrete. Available in a variety of sizes and head styles, perfect for versatile fastening applications.
5. Strike Anchor Bolts
Strike anchors (hammer drive anchors) are impact-set fasteners ideal for lightweight fixtures. Insert into pre-drilled holes and strike the pin to expand the anchor. Not typically removable once installed.
6. Split Drive Anchor Bolts
Split drive anchors feature a split base that expands as it is driven into concrete. Ideal for light-duty applications in concrete, brick, or block.
7. Lag Shield Anchors
Lag shield anchors are female anchors with ribbed sleeves and used in conjunction with lag bolts. Insert into pre-drilled holes and expand by threading in a lag screw. Ideal where vibration or movement could affect the connection.
Which Anchor Bolt is Right for You?
To select the proper anchor bolt, consider the following factors:
- Hole diameter (larger holes = greater load capacity)
- Embedment depth (deeper = stronger)
- Base material of the fixture
- Environmental exposure (e.g., moisture, corrosion risk)
- Load type (shear, tension, vibration)
- Concrete strength and type
- Spacing and edge distance requirements
