1-11. Anchors. Fastening wood or other materials to concrete or other
materials has always been a task for carpenter's. Anchors
(fasteners) for such work can be divided into three general
categories. The first group includes anchors installed during the
initial construction. The second group includes anchors installed in
solid concrete or masonry after construction is completed. The third
group includes anchors installed in masonry, plastic, or drywall that
has a hollow space behind it.
a. Anchor Bolts. Anchor bolts (Figure 143) a used to fasten
sills to masonry foundations. These bolts are used to fasten the
sill to the footers. Anchor bolts are installed when placing the
footer while the concrete is still wet.
Anchor bolt installation
b. Expansion Anchor Bolts. Lead screws, plastic anchors, and lag
expansion shields all work with the same basic idea. Drill a proper
size hole and insert the expansion shield into the hole. The
insertion of the screw or lag bolt expands the fastener to provide a
secure hold. Figure 144 shows how expansion anchors work.