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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
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including
insurance mortgage, in our performance, in our
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decisions, actions, and results to make sure
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geotechnical contracting industry. Please
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http://www.rembco.com/.
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Footing Foundations
JULY
1997
CALTRANS FOUNDATION MANUAL
4-9
water and can therefore be neglected. When the water table is at or below the base of the
footing, the submerged unit weight,
.
sub
=
.
sat
-
.
w
, is used in the first term of the bearing
capacity equation. The result, when the water table is at the bottom of the footing, is to
reduce the first term of the equation by approximately 50%. If the water table is above the
bottom of the foundation, the surcharge unit weight is also affected, and the submerged
unit weight must be used in the third term of the equation.
Figure 4-8: Surcharge Load on Soil
Moisture reduces the apparent cohesion of clay and therefore, the shear strength. The unit
weight of clay is also reduced when submerged in water (saturated). In saturated clays in
undrained shear, the foundation width has little effect on bearing capacity.
It is apparent that bearing capacity of both cohesionless and cohesive soils will be reduced
by rising water tables. This can be seen in the general bearing capacity formula when the
lighter submerged unit weight of soil is substituted for the dry unit weight. Therefore, the
effects of a rising water table on the bearing capacity of the footing soil mass, at any time
during construction, must be considered.
Structure related factors affecting the bearing capacity are the depth of footing below
ground line (D
f
) and the footing shape.
The term D
f
is used in determining the overburden, or surcharge, load acting on the soil at
the plane of the bottom of footing (Figure 4-8). This surcharge load has the net effect of
increasing the bearing capacity of the soil by restraining the vertical movement of the soil
outside the footing limits.
Theoretical solutions for ultimate bearing capacity are limited to continuous footings
(LENGTH/WIDTH
=
10). Shape factors for footings other than continuous footings have
been determined primarily through semi-empirical methods. In general, the ultimate