01 July 1997
(a) The diameter and wall thickness must be at least the minimum values specified. Thicker
walls may be required to properly drive the piles without damage or to achieve adequate pile penetration.
Dimensions of steel piles are given in TM 5-809-7.
(b) Steel piles may corrode by reacting with oxygen and water to form the metal oxide.
Corrosion is minimized where oxygen is deficient such as in clays and clean, fresh water. The potential for
corrosion is often significant in swamps, peat bogs, caliche and coarse-grained soils, industrial and mine
waste areas, and sea water. Surface paint coatings and encasement in various materials such as concrete
are frequently applied to inhibit corrosion.
(c) Pipe piles may be ordered with machine-cut or flame-cut ends, or the ends may be
beveled if required for welding. Milled finishes are not required.
(d) Tip protection provided by steel shoes as shown in figure 1-2 is particularly important for
H-piles subject to hard driving to refusal in or on a hard layer.
c. General Installation Method. Driven piles are forced into the ground using a pile hammer resting or
clamped to the pile butt. A cap block assembly is fitted between the hammer and the pile. Alignment of the
pile with the hammer is provided by leads suspended by a crane, except when vibratory hammers are used.
(1) Impact Hammers. Impact hammers drive the pile into the ground by applying a dynamic force
to the pile butt. Several types of hammers are available depending on the energy requirement.
(2) Vibratory Drivers. Vibratory hammers drive the pile into the ground by a push and pull action of
counter-rotating weights. Vibratory action of the driver causes soil adjacent to the pile to be like a viscous