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11:27 PM
Page 150
Subgrade Preparations
150
Vibratory roller compaction of 4-inch maximum sand lift to complete a total of a 12-inch section.
P
roper subgrade preparation
the client, Shaw & Sons first installs
tions provided by the soil engineer(s).
is the first step to correctly
Mirafi 500 X Geotex fabric for soil sep-
Additional lifts are installed in the
forming a cast-in-place proj-
aration and stabilization. This prevents
same manner until the proper grade is
ect. The photos on these
additional cracking and displacement
achieved. Finally, equipment such as
pages show Shaw & Sons typical pro-
of concrete, keeping it securely and
vibrating rollers for large areas or walk-
cedure for installing based material and
evenly in place for the long term.
behind vibrating plates for pipe pene-
washed concrete sand. Although not
Next, sub-base or sand is installed in 4-
trations and edges should always be used.
specified and at no additional cost to
inch lifts and saturated to specifica-