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Micro Piles |
Pressure Grouting |
Rock Anchors |
Permeation Grouting
Soil Nailing |
Compaction Grouting |
Micropiles |
Injection Grouting |
Chemical Grouting
Our
techniques apply when adding new structures:
especially
rock anchor,
microfine cement,
soil nailing,
micropile
installations for
foundation support.
We
specialize in
slope stabilization,
anchors,
permeation grouting,
foundation repair
and support,
grouting,
soil nails,
rock drilling,
micropile installations, and
sinkholes. We
use a
problem-solving approach geotechnical
architecture of buildings, bridges,
water plants, sewage plants, tunnels,
sinkholes,
caisson,
shoring,
underpinning,
agriculture, and
roads
construction. We
are experienced in these applications:
micro piles,
sinkhole repair,
permeation grouting, pressure
grout,
soil nails,
chemical grouting,
micropiles,
compaction grout, and
rock anchors.
Our specialties are
rock anchor,
acrylamide and
compaction grouting,
mini piles,
sinkhole repair,
micropiles,
acrylamide grouting, and
soil nailing.
We will continue to
dedicate ourselves to
excellence,
including
insurance mortgage, in our performance, in our
integrity, and in our relationships with our
customers. We will carefully weigh our
decisions, actions, and results to make sure
that we remain the most trusted name in the
geotechnical contracting industry. Please
visit our website
http://www.rembco.com/.
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JULY
1997
Driven Piles
7-22
The diesel hammer is difficult to keep operating when driving piles in soft material. As most
of the energy is absorbed by movement of the pile downward, little remains to lift the ram
high enough to create sufficient compression in the next downstroke to ignite the fuel. To
resume operation, the ram must again be raised by the cable hoist.
It is generally accepted that the energy output of an open end diesel hammer is equal to the
ram weight times the length of stroke. This combination ignores any component of the
explosion which acts downward. In production pile driving, the stroke is a function of the
driving resistance, the pile rebound, and the combustion chamber pressure. The combus-
tion chamber pressure, in turn, will be affected by the general condition of the hammer as
well as the fuel timing and the efficiency of combustion. Accordingly, manufacturer’s
energy ratings are based upon the hammer operating at refusal with almost all the energy
of combustion developing the upward ram stroke.
Diesel hammers are very versatile. They may be connected to almost any leads. Since they
do not require an additional energy source, such as steam or air, the size of the pile crew
can be reduced. On occasion, piles are driven with as few as three workers, including the
crane operator.
These hammers typically operate within a speed of 40 to 60 blows per minute and have
strokes in excess of 10 feet. Although these hammers will drive any type of pile, their stroke
is dependent on soil conditions. Hard driving in harder soils results in increasing stroke
lengths, thus providing increasing hammer energies; while easy driving in softer soils
results in lower stroke lengths and lower hammer energies.
Diesel hammers are noisy and they tend to spew oil and grease throughout. They also emit
unsightly exhaust.
The Engineer should:
NO.
ITEM DESCRIPTION
1
Have the manufacturer’s current specifications for the type and model of
hammer being used.
2
Ensure all required parts of the hammer are intact and in good operating
condition.
3
Be aware of the actual stroke of the hammer during driving and that it will
vary depending on soil resistance.