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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
Slurry Displacement Piles
9-20
Usually, in order for the mineral slurry to meet the physical property requirements of the
contract specifications, the mineral slurry will require recirculation and cleaning during
and after the drilling operation. Occasionally without any action on the part of the Contrac-
tor, the mineral slurry will meet the physical property requirements of the contract specifi-
cations during and after the drilling operation, in which case continuous agitation of the
mineral slurry in the drilled hole is acceptable. However, the contract specifications also
require that any mineral slurry which is continuously agitated in the drilled hole and
exceeds the physical property requirements must be recirculated and cleaned.
Should the mineral slurry’s properties change dramatically during the drilling operation,
there are many chemical additives available that can reduce the filter cake thickness, lower
the mineral slurry’s pH, and increase the mineral slurry’s viscosity. Additives that reduce the
filter cake thickness and increase the mineral slurry’s viscosity include organic colloids and
lignosulfonates. Additives that lower the mineral slurry’s pH include soda ash and pyro-
phosphate acid. Additives that decrease the mineral slurry’s viscosity include tanins and
polyphosphates. Caltrans has little experience with chemical additives and their use should
be discussed with the Office of Structural Foundations and the Office of Structure Construc-
tion in Sacramento. In general, modifying the pH of the mineral slurry with chemical
additives is not a problem.
Mineral slurries may be used in most types of ground formations. They work best in
cohesionless sands and open gravels. Caution must be taken when using mineral slurries in
cohesive materials because they may contain clays that can be incorporated into the
mineral slurry and rapidly change the mineral slurry’s physical properties. In addition,
cohesive materials can reduce filtration and filter cakes may not form.
Disposal of mineral slurries can be difficult. Due to their particulate nature, they are
hazardous to aquatic life and cannot be disposed of on site or at locations where they can
enter State waters. The contract specifications require that any materials resulting from the
placement of piles under mineral slurry be disposed of outside the highway right-of-way in
accordance with Section 7-1.13 of the Standard Specifications. Because they often contain
chemical additives, mineral slurries can be considered to be hazardous materials which
must be disposed of in landfills. This can be very expensive and can defeat the economic
advantage of using the slurry displacement method over other means of construction of
CIDH piles.