The ingress of air and moisture into the concrete can cause
corrosion of the steel reinforcement and lead to a deterioration in
concrete strength.
Therefore, a measure of the ease of movement of liquids and
gases through the surface layer of the concrete is a better method
of assessing the soundness and expected life of concrete than
strength alone.
Permeability is recognized as being the most important parameter in
assessing concrete durability.
The depth test is performed by drilling a hole 10 mm diameter x 40 mm
deep, and plugged with a silicone rubber plug.
A hypodermic needle is passed into the stopper; the water permeability
test is performed by measuring the time of absorption needed
by the water introduced into the void by pressure.
For the air permeability test, a vacuum pressure is created in the
void, and the time needed to rise this pressure is measured.
Surface permeability tests can be carried out by clamping a stainless
steel chamber on the smooth surface of the concrete.
SPARE
C375-11 Silicone rubber plugs. Pack of 25 pcs.
