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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
7-30
The manufacturers of these types of hammers claim the following:
NO.
ITEM DESCRIPTION
1
Hammer efficiencies in the range of 80% to 98%, while claiming diesel
hammers to have an efficiency in the range of 30% to 40%.
2
Due to the increased efficiency of the hammers and because more energy is
transmitted through the hammer, there is less internal stress of the pile, less
pile damage, etc.
3
They claim the operation to be quieter than the typical diesel hammer.
4
The typical exhaust of the diesel hammer is eliminated, since only the
motor driving the hydraulics is the source of exhaust.
5
Avoids diesel hammer problems of soft ground starting and operating in
extreme climates.
A hydraulic hammer has been tested on a Caltrans project. The hammer was tested in
conjunction with a single acting diesel hammer. Piles were driven with both hammers.
Bearing of the hydraulic driven piles were verified by means of a retap, using the diesel
hammer.
The results indicated that the diesel hammer required twice as much energy to move the
pile one foot when compared with the energy of the hydraulic hammer.
Currently the hydraulic hammer is not considered an approved impact hammer for
determining the bearing value of a driven pile. The problem with the use of such hammers
is the verification of energy induced. The question remaining is to the relationship of the
hydraulic hammer versus the Engineering News-Record (ENR) formula.
Although we do not allow the hydraulic hammer to be used with the ENR formula, the
Wave Equation Analysis has been used on this type of hammer successfully.
General Hammer Information
Section 49-1.05 of the Standard Specifications requires that the Contractor furnish an
approved hammer having sufficient energy to drive piles at a penetration rate of not less
than
1
/
8
-inch per blow at the required bearing value. In effect, this specification places a
lower limit on the hammer size because hammer size, in most cases, is related to energy. An
upper limit is not specified.