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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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Driven Piles
JULY
1997
7-27
Vibratory Driver/Extractor
Because there is no way to determine the amount of energy delivered to the pile, Section 49-
1.05 of the Standard Specifications prohibits the use of the vibratory hammer for driving
permanent contract piles. However, it is frequently used by contractors for items of a
temporary nature (i.e. placing and extracting sheet piles, etc.). They are also typically used
as a means of extracting piles.
Vibratory pile drivers/extractors could be likened to ministroke, high blow rate hammers.
However, the familiar vibratory pile drivers in standard use today do not contain linearly
reciprocating weights or rams. Instead, they employ two balanced rotating weight sets,
which are eccentric from their centers of rotation. Moving in opposite directions, they
impart a vibration that is entirely vertical. This motion is transmitted to the pile through
the hydraulic clamps of the driving head. The pile in turn transmits the vibratory action to
the soil allowing the soil granules to be more readily displaced by the pile tip. The same
action works even more effectively for extracting piles. Refer to Figure 7-16.
The effectiveness of a vibratory unit is dependent upon the interrelationship of the perfor-
mance factors inherent to the unit. The larger the eccentric moment, the more potential
vibratory force the driver possesses. In order to realize this potential force, the driver must
operate with the proper frequency and amplitude.
Heavier piles mean higher vibratory weight which tends to reduce amplitude. So as piles get
larger, it is necessary to use drivers with larger eccentric moments. The nonvibratory weight
has the effect of extra weight pushing the pile downward.
Vibratory drivers are most effective in granular soil conditions, but recent developments and
new techniques have also made them effective in more cohesive soils. They can handle a
variety of piling, including steel sheets, steel pipe, concrete, timber, wide flange sections,
“H” piles, as well as caissons. They do not create as much ground vibration as normal pile
driving, thereby making the vibratory hammer desirable when possible damage to adjacent
structures could occur.
The vibratory hammer has been permitted to drive a bearing pile to a point which would be
a specified distance from expected final penetration. An accepted impact hammer has then
been placed upon the pile to take it to acceptable bearing and final penetration in the
normal fashion. Situations where this is of some use is where alignment of a pile is critical.
The vibratory hammer allows the operator to minimize the rate of penetration of a pile,
thereby allowing for more precise alignment of a pile as it gets started into the ground.