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Micro Piles |
Pressure Grouting |
Prestressed 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
Cofferdams and Seal Courses
12-8
Seal Course Inspection
In addition to the usual pre-pour matters, such as access and suitability or adequacy of
equipment, sufficient soundings should be taken to verify elevations. Particular care should
be given to the perimeter of the cofferdam and the pile locations. Soundings can be accom-
plished using a .at plate of suitable size and weight on the end of a rod or rag tape.
This device can be used to not only determine elevations, but, to some extent, can be used to
determine the nature of the material (soft or firm). During the pour, soundings are again
used to verify the elevation of the top surface of concrete. Because of the type of operation,
surface irregularities can be expected, particularly in pile footings. The important thing is
to check for proper thickness throughout and the absence of excessive low spots. The
Standard Specifications require a minimum cure period of 5 days before dewatering.
Thickness of Seal Course
A chart for determination of seal course thickness is included in Appendix I. Certain
safeguards or safety factors are built into this chart. For example, seal courses in pile
footings are constructed one foot thicker than required to allow for surface irregularities.
The bond friction between sheet piling and concrete is disregarded. The bond friction
between seal course concrete and foundation piles is limited to 10 Pounds per Square Inch
(PSI). Minimum thickness of seal course concrete is 2 feet. This subject is also covered in
Bridge Construction Memo 130-4.0 and Bridge Design Aid “Seal Course” included in
Appendix I.
Dewatering
Section 51-1.10 of the Standard Specifications requires a minimum cure period of 5 days
(at concrete temperatures of 45
°
F or more) before dewatering may begin. Dewatering can
present some anxious moments since the cofferdam and the seal course will be put to the
test.
Dewatering is sometimes conducted in stages for a moderately deep cofferdam. At each
stage intermediate bracing systems are installed before proceeding deeper. Depending on
the particular design, these internal braces restore the stability of the system.