Hollow Anchor Rod: A rod that is inserted deep into the rock and soil interior to control their deformation, including components such as washers and nuts.

Grout Anchor: A rod that uses cement mortar for anchoring, this anchor is cost-effective, with relatively weak holding power, easy to install, and is more commonly used in rock structures with intact slopes or temporary anchoring. Grout anchors are mainly used in tunnel construction and are not often seen underground.

Theoretically, hollow grouting anchor bolts are more effective than mortar anchor bolts. If not grouted, both hollow and mortar anchor bolts have very limited effects. Hollow anchor bolts are hollow, and their strength is slightly weaker than that of mortar anchor bolts.