As a Builder, you will coordinate and direct
pile-driving operation crews. Piles include many
different types and materials. The more common types
are covered next.
TIMBER BEARING PILES are usually straight
tree trunks with the limbs and bark removed, and all
timber will be PRESSURE-TREATED. These piles, if
kept continuously wet, will last for centuries; however,
they are used for low-design loads because of their
vulnerability to damage while they are being driven into
the ground. The small end of the pile is called the tip;
the larger end is called the butt. Timber piles range from
16 to 90 feet in length with a tip diameter of at least 6
inches. The butt diameter is seldom less than 12 inches.
STEEL BEARING PILES are usually H-pile
(having an H-shaped cross section). These piles are
usually used for driving through bedrock or until
refusal. A steel pile can also be a pipe pile with a
circular cross section.
A pipe pile can be either an
open-end pile or a closed-end pile, depending on
whether the bottom end is open or closed.
CONCRETE PILES, as shown in figure 8-12, may
be either precast or cast in place. Most precast piles
used today are pretensioned and are manufactured in
established plants. These piles are made in square,
cylindrical, or octagonal shapes. When driven into soil
or mucky soil, they are usually tapered. Cast-in-place
piles are cast on the jobsite and are classified as shell
type or shell-less type. The shell type is formed when
the hollow steel tube (shell) with a closed end is driven
into the ground and it is filled with concrete. The
shell-less type is formed when first a casing and core
are driven to the required depth. The core is removed,
and the casing is filled with concrete. The casing is then
removed, leaving the concrete in contact with the earth.
Sheet piles, made of wood, steel, or concrete, are
equipped or constructed for edge-joining, so they can
Figure 8-12.Types of concrete piles.
be driven edge-to-edge to form a continuous wall or
bulkhead. A few common uses of sheet piles are as
1. To resist lateral soil pressure as part of a
temporary or permanent structure, such as a retaining
2. To construct cofferdams or structures built to
exclude water from a construction area
3. To prevent slides and cave-ins in trenches or
The edges of steel sheetpiling are called
INTERLOCKS (fig. 8-10), because they are shaped for
locking the piles together edge-to-edge. The part of the
pile between the interlocks is called the WEB.