For installing anchor bolts in existing concrete, which type of anchor bolt is most commonly used?

When installing anchor bolts in existing concrete, mechanical expansion anchors are commonly used due to their reliability and straightforward installation process. These anchors work by expanding against the sides of the drilled hole in the concrete as a bolt is tightened. This creates a secure hold, which is crucial for applications where the anchor must bear heavy loads or withstand vibration.

Mechanical expansion anchors provide immediate holding strength upon installation, making them suitable for both temporary and permanent applications. They are also versatile as they can be used for various materials and conditions, adjusting well to the nuances of different concrete surfaces.

The other types of anchors have specific uses or conditions where they are most effective. Resin anchors, for instance, utilize epoxy adhesive to provide a bond between the anchor and the concrete. While they can offer strong bonds, they often require a curing period and are typically chosen in situations where the load conditions are not as immediate or where environmental factors such as moisture may be a concern. Hydraulic expansion anchors, while also providing strong holding power, tend to be used more in heavy-duty applications and often require more complex installation techniques. Cementitious anchors are specialized for particular applications and are less common in general use for installing anchor bolts in existing concrete structures.