Figure 7-17.-Typical beam and girder form.
stripped and the bottom left in place until the concrete
has hardened enough to permit removal of the
shoring. The latter type of form is preferred, and
details for this type are shown in figure 7-17.
Although beam and girder forms are subjected to very
little bursting pressure, they must be shored up at
frequent intervals to prevent sagging under the weight
of fresh concrete.
The bottom of the form should be the same width
as the beam and should be in one piece for the full
width. The sides of the form should be 1-inch-thick
tongue-and-groove sheathing and should lap over the
bottom as shown in figure 7-17. The sheathing is
nailed to 2-by-4-inch studs placed on 3-foot centers.
A 1-by-4-inch piece is nailed along the studs. These
pieces support the joist for the floor panel, as shown
in figure 7-18, detail E. The beam sides of the form
are not nailed to the bottom. They are held in position
by continuous strips, as shown in detail E. The
Figure 7-18.-Assembly of beam and floor forms.