Concrete
has a very high compressive strength compared to its tensile strength which is
very low. It is possible to increase this tensile strength by introducing rebar
in to concrete to make a reinforced concrete structure which can then take both
compressive and tensile stresses and make for structures that have strength and
durability.
Concrete
lends itself very easily to be molded into any shape that is desired, because
when it is first manufactured it is in a plastic state, which over a short
period of time hardens, while continually developing strength. CSI finds rebar etc in concrete to reinforced concrete needs to be put at very specific locations so that it
allows the structure to have the required tensile strength. This is done by
using spacers and other devices to lock rebar into the specific required
locations, which remain so, even when the fluid concrete is poured into the
formwork that makes up the shape of the desired structure. It can be in
columns, walls, beams, slabs or any shape desired. Building codes determine the
distance this rebar needs to be at from the surface of the concrete. Rebar is
made of steel which is vulnerable to rust from atmospheric conditions. This is
why rebar needs to be kept at a certain distance within the concrete to prevent
any rust formation. Rust formation can cause rebar to lose its form and
strength and thus affect the strength of the reinforced concrete structure.
When this
requires the concrete structure to be drilled through or partially, it is very
important to make sure that any such modification is not hampered by the
presence of the rebar. It then becomes very important to know the exact
position of the rebar, so that any drilling or breaking done does not come
across a rebar.
Technologies
are available that allow the location of the rebar in concrete to be
pinpointed, without any necessity for damaging the concrete to locate the
rebar. These concrete scanning operations use ground penetrating radar to
locate rebar. This allows the exact location for the rebar to be established so
that any subsequent operations can avoid damaging them. There are times, when a
structure is showing signs of distress, and at such times one of the first
things that engineers do is check on the position of the rebar, as any shift
from previously designed parameters can lead to weaker structures. Location of
rebar in concrete can help engineers to assess the soundness of a structure.
Rust
formation can cause rebar to lose its form and strength and thus affect the
strength of the reinforced concrete structure.
It then
becomes very important to know the exact position of the rebar, so that any
drilling or breaking done does not come across a rebar. Technologies are
available that allow the location of the rebar in concrete to be pinpointed,
without any necessity for damaging the concrete to locate the rebar.
C.S.I.
Concrete Scanning & Investigation
Broadbeach,
QLD
4218
Contact us: 0426 508 755
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