PILE DRIVING ANSWERS AND QUESTIONS SET A+
✔✔Convertible Diesel Pile Hammer - ✔✔A diesel hammer which can be operated either
open-end (single-acting) or closed-end (double-acting).
✔✔Cored Pile - ✔✔A pile formed by removing earth prior to pile installation.
✔✔Cushion - ✔✔Material inserted between the ram of the pile hammer and the driving
cap and also between the driving cap and the pile. This material provides a uniform
distribution of impact forces. Typical materials used for cushioning include steel,
aluminum, coiled cable, and wood.
✔✔Cutoff - ✔✔The prescribed elevation at which the top of a driven pile is cut. Also, the
portion of pile removed from the upper end of the pile after driving.
✔✔Cylinder Pile - ✔✔Hollow circular pile constructed of concrete or steel.
✔✔Density - ✔✔The weight or mass per unit of volume. In reference to soil, the term
usually indicates weight per unit volume and is synonymous with unit weight.
✔✔Design Load - ✔✔The load which the pile is intended to carry without excessive
movement and with an acceptable factor of safety against plunging failure.
✔✔Diesel Hammer - ✔✔A pile hammer, which carries its own diesel fuel to generate
power internally.
✔✔Differential-Acting Hammer - ✔✔A fluid-powered hammer in which fluid lifts the ram
in the upstroke and is exhausted into and combined with addition fluid entering over the
piston to take advantage of differential piston areas to accelerate the ram and to act in
concert with gravity on the down stroke
✔✔Double-Acting Hammer - ✔✔A closed pile hammer in which steam/air/diesel
explosion/etc. is used both to lift the ram and to accelerate the down stroke.
, ✔✔Down Drag - ✔✔The negative friction of soil gripping a pile in the case of settling
soils. This condition adds load to the installed pile.
✔✔Drive Cap (Helmet) - ✔✔A steel cap placed over the pile butt to prevent damage to
the pile during driving. It is formed to accept a specific-shaped pile, along with its
cushion, if used.
✔✔Drive Sleeve - ✔✔A type of pile splice used at the joints of pipe pile to splice two
sections together.
✔✔Drive-Fit Collar - ✔✔A steel collar used for splicing pipe piles. Both pieces of pipe fit
inside the collar and after the first blow of the hammer, the fit is tight due to the taper of
the inside of the collar. Does not normally require welding; pipe is held by friction
✔✔Driving Criteria - ✔✔The requirement for a resistance of a pile to penetration stated
in blows per increment of depth OR required tip elevation of the pile.
✔✔Driving Head Attachments - ✔✔The attachment that holds the pile firmly in place
during the upstroke of the ram and prevents distortion to the top of the pile.
✔✔Driving Log - ✔✔Field record of each driven pile including location, hammer model,
pile type, blow count per unit (e.g., foot) of penetration, final resistance, driven length,
etc.
✔✔Driving Plan - ✔✔A written plan that describes the step-by-step procedure of the
entire pile driving operation from pile manufacturing, arrival, storage, hoisting, driving,
releasing from safety line and post driving with an emphasis on safety
✔✔Driving Theatre - ✔✔The entire area where, in the event of a pile accident resulting
in the collapse of the crane and leads system, personnel on the ground could be struck
by falling equipment or objects dynamically affected by falling equipment such as stored
piles, towers, other standing equipment.
✔✔Drop/Gravity Hammer - ✔✔A weight configured to slide in pile hammer leads or
within a hollow pile which has a formed bale or swivel at its top by which it can be
mechanically lifted and dropped to drive pile.
✔✔Eccentric Moment - ✔✔A basic measure or indication of the size of a vibratory
driver. It is the product of the weight of the eccentricities multiplied by the distance from
the center of rotation of the shafts to the center of gravity of the eccentrics.
✔✔Embedment - ✔✔The length of pile from the ground surface, or from the cutoff
below the ground, to the tip of the pile.
✔✔Convertible Diesel Pile Hammer - ✔✔A diesel hammer which can be operated either
open-end (single-acting) or closed-end (double-acting).
✔✔Cored Pile - ✔✔A pile formed by removing earth prior to pile installation.
✔✔Cushion - ✔✔Material inserted between the ram of the pile hammer and the driving
cap and also between the driving cap and the pile. This material provides a uniform
distribution of impact forces. Typical materials used for cushioning include steel,
aluminum, coiled cable, and wood.
✔✔Cutoff - ✔✔The prescribed elevation at which the top of a driven pile is cut. Also, the
portion of pile removed from the upper end of the pile after driving.
✔✔Cylinder Pile - ✔✔Hollow circular pile constructed of concrete or steel.
✔✔Density - ✔✔The weight or mass per unit of volume. In reference to soil, the term
usually indicates weight per unit volume and is synonymous with unit weight.
✔✔Design Load - ✔✔The load which the pile is intended to carry without excessive
movement and with an acceptable factor of safety against plunging failure.
✔✔Diesel Hammer - ✔✔A pile hammer, which carries its own diesel fuel to generate
power internally.
✔✔Differential-Acting Hammer - ✔✔A fluid-powered hammer in which fluid lifts the ram
in the upstroke and is exhausted into and combined with addition fluid entering over the
piston to take advantage of differential piston areas to accelerate the ram and to act in
concert with gravity on the down stroke
✔✔Double-Acting Hammer - ✔✔A closed pile hammer in which steam/air/diesel
explosion/etc. is used both to lift the ram and to accelerate the down stroke.
, ✔✔Down Drag - ✔✔The negative friction of soil gripping a pile in the case of settling
soils. This condition adds load to the installed pile.
✔✔Drive Cap (Helmet) - ✔✔A steel cap placed over the pile butt to prevent damage to
the pile during driving. It is formed to accept a specific-shaped pile, along with its
cushion, if used.
✔✔Drive Sleeve - ✔✔A type of pile splice used at the joints of pipe pile to splice two
sections together.
✔✔Drive-Fit Collar - ✔✔A steel collar used for splicing pipe piles. Both pieces of pipe fit
inside the collar and after the first blow of the hammer, the fit is tight due to the taper of
the inside of the collar. Does not normally require welding; pipe is held by friction
✔✔Driving Criteria - ✔✔The requirement for a resistance of a pile to penetration stated
in blows per increment of depth OR required tip elevation of the pile.
✔✔Driving Head Attachments - ✔✔The attachment that holds the pile firmly in place
during the upstroke of the ram and prevents distortion to the top of the pile.
✔✔Driving Log - ✔✔Field record of each driven pile including location, hammer model,
pile type, blow count per unit (e.g., foot) of penetration, final resistance, driven length,
etc.
✔✔Driving Plan - ✔✔A written plan that describes the step-by-step procedure of the
entire pile driving operation from pile manufacturing, arrival, storage, hoisting, driving,
releasing from safety line and post driving with an emphasis on safety
✔✔Driving Theatre - ✔✔The entire area where, in the event of a pile accident resulting
in the collapse of the crane and leads system, personnel on the ground could be struck
by falling equipment or objects dynamically affected by falling equipment such as stored
piles, towers, other standing equipment.
✔✔Drop/Gravity Hammer - ✔✔A weight configured to slide in pile hammer leads or
within a hollow pile which has a formed bale or swivel at its top by which it can be
mechanically lifted and dropped to drive pile.
✔✔Eccentric Moment - ✔✔A basic measure or indication of the size of a vibratory
driver. It is the product of the weight of the eccentricities multiplied by the distance from
the center of rotation of the shafts to the center of gravity of the eccentrics.
✔✔Embedment - ✔✔The length of pile from the ground surface, or from the cutoff
below the ground, to the tip of the pile.
