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COMPACTION
The process of construction relies heavily
on the compaction of the soil before any
building operation can commence. Soil
compaction is used for the support of struc-
tural entities such as building foundations,
roadways, walkways and earth retaining
structures, to name a few. For a given soil
type certain properties may deem it more
or less desirable to perform adequately
for a particular circumstance. In general,
the preselected soil should have adequate
strength, be relatively incompressible so
that future settlement is not significant,
be stable against volume change as wa-
ter content or other factors may vary, be
durable and safe against deterioration and
possess proper permeability.
To ensure adequate soil compaction is
achieved, project specifications will indi-
cate the required soil density or degree
of compaction that must be achieved. The
composition of the soil has a great influ-
ence on the maximum dry unit weight and
optimum moisture content. It also has a
great influence on how the materials should
be compacted in given situations.
Compaction is accomplished by use of
heavy equipment. In sands and gravels vi-
bratory type equipment is used. This caus-
es re-orientation of the soil particles into
a denser configuration. In silts and clays,
a pad foot roller is frequently used to cre-
ate small zones of intense shearing which
drives air out of the soil.
When selecting equipment for compaction
it is therefore essential to choose the most
effective type of machine for the job which
is determined by the soil type. There are
various types of equipment available such
as, the Rammer which gives high impact
forces, the Forward Plate Compactor de-
signed for mainly granular soils and Roll-
ers of various sizes and weights that are
normally employed in road construction
soil compression. Some of the most com-
mon types are the walk-behind and ride-
on rollers.
b
INTRODUCTION TO
COMPACTION
“The composition of the
soil has a great influence
on the maximum dry unit
weight and optimum
moisture content. It also
has a great influence on
how the materials should
be compacted in given
situations.”
CAPITAL EQUIPMENT NEWS
FEBRUARY 2015
6