An adhesive anchor is a reinforcing bar or threaded rod inserted into a drilled hole in hardened concrete with a structural adhesive acting as a bonding agent between the concrete and the steel. Typically, the hole diameter is only about 10-25% larger than the diameter of the reinforcing bar or threaded rod. Structural adhesives for this type of anchor are available prepackaged in glass capsules, in dual-cartridge injection systems, or as two component systems requiring user proportioning. The typical types of adhesive anchor systems and types of adhesive are shown in Figure 8.13.
A grouted anchor may be a headed bolt, threaded rod with a nut at the embedded end, or a deformed reinforcing bar with or without end anchorage installed in a preformed or drilled hole with a Portland cement and sand grout or a commercially available premixed grout [16]. Typically, the hole size for grouted anchors is about twice the diameter of the anchor. The details of grouted anchors are not described in this chapter.