Formwork for Concrete Structures by R.L.Peurifoy and G.D- By EasyEngineering.net

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Forms for Walls 243
FIGURE 9-9 Details of wall form.
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Forms for Walls with Pilasters and Wall Corners
Figure 9-9(a) illustrates a method of constructing forms for a wall
with a pilaster. The forms for the wall are erected first, followed
by the forms for the pilaster. This order is reversed in stripping
the forms.
Figure 9-9(b) illustrates a method of constructing forms for a wall
corner. Because nails alone may not provide sufficient strength to join
the two wales at Point A, two 2 × 6 ties, extending the full height of
the form, are attached as shown to provide additional strength.
Forms for Walls with Counterforts
Figure 9-10 illustrates a method of constructing forms for a wall with
a counterfort. The wall forms are erected first, and then the two sides
and top form for the counterfort are prefabricated and assembled in
position, as illustrated.
Because of the substantial pressure exerted by the fresh concrete
on the back sheathing of the counterfort, this form must be securely
fastened to the wall forms to prevent it from pulling away from the
wall forms. Also, the counterfort forms must be securely anchored to
prevent vertical uplift from the pressure on the underside of the back
sheathing.
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