These piles should be spaced 6 to 10 feet apart center-to-center in one direction, and 5 feet apart center-to-
center in the other direction (d). Bearing piles support the wharf or pier framework or decking. The length varies
according to the depth of the water.
The decking should be at least 3 (c) inches thick and joined directly over the joists. The joints should be staggered
for greater strength.
If the decking is 3 inches thick, 60d nails or 6-inch (b) spikes should be used. If the decking is 4 inches, a 7- or 8-
inch spike should be used.
Timber carriers (a) are considered two-man tools. They are primarily used to pick up and carry timber.
Decay is caused by the action of low parasitic forms of plant life known as fungi (a). This decay facilitates the
action of termites and marine borers.
Caps are large timbers which are placed on top of the bearing piles. Pier girders (b) rest on the caps and are
secured to the caps with drift pins.
In wharf construction, the girders may rest directly on the bearing pies (a). They would be secured with drift
The bearing (a) piles support the pier framework and decking. They are spaced 6 to 10 feet apart in one direction
and 5 feet apart in the other direction, all center-to-center.
The piles are 60 to 80 feet in length; the length varies according to the depth of the water and condition of the
10. Joists are usually spaced from 16-24 inches on center. If planned spacings may not support the intended load you
should use heavier joists rather than reduce the spacings (c).
Soil and wood treatment, termite shields, and preservative treatment are some of the methods used to discourage
termite infiltration, but if termite colonies still accumulate, consult your entomologist (c).
Usually timber (a) is the most widely used because it is more economical, lighter, and easier to work.
serviceable life of timber, however, is shorter because it is subject to decay by fungi action.
13. Piers (b) are constructed perpendicular or approximately perpendicular to the shore line. Vessels can tie up on
Loading dock foundations in most cases are spaced from 6 to 10 feet (b) apart. They must be spaced according to
the weight they may carry.