01 July 1997
(1) Pile Preparation. Piles will be prepared for installation by splicing to required lengths,
attachment of fittings such as driving shoes and bands, and application of coatings. Coatings to protect the
pile from corrosion or to reduce negative skin friction may be required by the specifications.
(a) Timber Piles. Steel bands may be required at the top of the pile and at specified intervals
to maintain the integrity of the pile. The top of the pile will be cut square with the pile axis and chamfered
when necessary to fit the drive cap. A steel band may also be necessary at the top to prevent splitting. All
cuts should be chemically treated after driving if the pile had previously been treated. Driving shoes may
also be required at the pile tip.
(b) Steel Piles. Splices may be required to achieve the necessary lengths. Half of the splice
may be attached or welded to the section to be installed to minimize time required to splice the section to the
pile previously driven into the ground. Driving shoes will be attached or welded to the tip if required by the
(c) Concrete Piles. Sections of concrete piles will be attached with splice or joint fittings while
being cast by the manufacturer.
(2) Pre-excavation. The soil may require Pre-excavation to facilitate installation. Preboring and
prejetting or jetting while driving are the most common methods of facilitating the pile installation.
(a) Pre-excavation may be required to assist installation in hard or dense soils or to reduce or
eliminate soil heave.
(b) The type of Pre-excavation depends on the soils. Jetting is effective in granular soil, while
preboring is effective in cohesive soil. If jetting is permitted, restrictions will be required on the size of the jet,
volume and pressure of water, and the depth of jetting to minimize the loss of pile capacity after installation.
Jetting disturbs the soil around and below the pile. The pile should be seated with an impact hammer after
(3) Handling and Lofting Piles. Careful handling of the pile is required while the pile is being
aligned into the proper position for driving.
(a) Hollow piles will not be dragged along the ground with the open end first to prevent the pile
from picking up debris.
(b) Pointed tools will not be used with timber piles that could damage the wood.
(c) Concrete piles will be handled at designated contact points. The top slings for lifting
coated concrete piles should be attached to the bottom sling to prevent slippage and damage to the coating
and to provide safety while lifting. Coatings applied to reduce negative skin friction are usually not applied at
the bottom of the pile so that the bottom sling will hold in place. Coatings applied full length require special
provision for lifting such as boring lugs into the concrete.
(d) Holes can be cut in steel piles for attachment of lifting shackles if the portion of the pile with
the holes will later be cut off.
(4) Length of Piles in the Leader. If part or total payment for pile installation is based on the length
of pile raised in the leaders, then a record will be kept of the length for each pile in the leader. For piles
where length is added to the leader, the pile spliced, and some of the length cut from the pile, the length of
pile over which payment is made will be adjusted to avoid payment for pile length that is cut from the pile.
(5) Splicing. Splices are necessary if the length of the pile cannot be made long enough to reach