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

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Properties of Form Material 75
Size of Nail,
penny-weight
Length,
in.
Diameter,
in.
Bending Yield
Strength,
lb per sq in.
6d 2 0.113 100,000
8d 2½ 0.131 100,000
10d 3 0.148 90,000
12d 3¼ 0.148 90,000
16d 3½ 0.162 90,000
20d 4 0.192 80,000
30d 4½ 0.207 80,000
40d 5 0.225 80,000
50d 5½ 0.244 70,000
TABLE 4-22
Sizes and Properties of Common Wire Nails
the two resistances. The resistances of nails are discussed in the following
sections.
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Withdrawal Resistance of Nails
The resistance of a nail to direct withdrawal from wood is related
to the density or specific gravity of the wood, the diameter of the
nail, the depth of its penetration, and its surface condition. The NDS,
published by the American Forest & Paper Association (AF&PA), is a
comprehensive guide for the design of wood and its fastenings. The
association’s Technical Advisory Committee has continued to study
and evaluate new data and developments in wood design. The information
given in the following tables is from ref. [1].
Table 4-23 provides the nominal withdrawal design values for
nails and species of wood commonly used for formwork. Withdrawal
values are given only for nails driven in side grains [1]. Nails are not
to be loaded in withdrawal from the end grain of wood. The nominal
values are provided in pounds per inch of penetration for a single nail
driven in the side grain of the main member with the nail axis perpendicular
to the wood fibers. Tabulated values should be multiplied by
the applicable adjustment factors to obtain allowable design values.
Lateral Resistance of Nails
For wood-to-wood connections, the lateral resistance of nails depends
on the nail diameter and depth of penetration, the bending yield
strength of the nail, the thickness and species of the wood, and the
dowel bearing strength of the wood.
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