Concrete modification by using polymeric
materials has been studied since the nineteen
sixties. Some polymers are already used to
modify the properties of concrete. The materials
used currently to reinforce the concrete matrix
adhere only by physical interactions and not
by primary chemical bonds.
A new alternative that is being evaluated
is the use of gamma radiation to modify the
material surface. This increases the compatibility
with concrete matrix. The enhanced compatibility
would allow improving both modulus and compressive
strength. Typically PP fiber is first irradiated
to several dosages of gamma rays and then
incorporated in concrete. It is observed that
at about 1.5-2 % level of of irradiated PP
fiber improves the performance of concrete
in both modulus as well as compressive strength.
Typically radiation dosage of about 10 kGy
is adequate.
Thus performance of concrete can be improved
by the use of irradiated PP fiber.
