Volume-IF - JantERmantER

DCPL-K4A02
c) In case the concrete at the joint has become so stiff that it cannot
be remoulded and mortar or slurry does not rise inspite of
extensive vibration, the joint will be left to harden for at least 12 - 24
hrs. It will then be treated as a regular construction joint, after
cutting the concrete to required shape and preparing the
surface as described under clause 3.12.
3.14 Repairs, Finishes and Treatment of Concrete surfaces
3.14.1 Adequate and sound concrete surfaces, whether formed or unformed, can
be obtained by employing a concrete mix of proper design, competent
formwork, appropriate methods of handling, placing and consolidation by
experienced workmen.
Unsound concrete resulting from improper mix design, incompetent
methods, equipment and formwork, poor workmanship and protection will
not be accepted and will have to be dismantled, removed and replaced by
sound concrete. The Engineer may, at his sole discretion, allow to retain
concrete with minor defects provided the Contractor is able to repair it by
approved methods. All concrete work shall be inspected by the
Contractor immediately after the forms are removed and he will promptly
report occurence of any defects to the Engineer. All repair works will be
carried out as per the instructions and in the presence of the Engineer or
his representative. Generally, repair work will consist of any or all of the
following operations :
a) Sack rubbing with mortar and stoning with carborundum stone.
b) Cutting away the defective concrete to the required depth and shape.
c) Cleaning of reinforcement and embedments. It may be necessary to
provide an anti-corrosive coating on the inforcement.
d) Roughening by sand blasting or chipping.
e) Installing additional reinforcement/welded mesh fabric.
f) Dry packing with stiff mortar.
g) Plastering, guniting, shotcreting etc.
h) Placing and compacting concrete in the void left bycutting out
defective concrete.
i) Groting with a cement sand slurry of 1:1 mix.
j) Repairing with a suitable mortar either cement or resin modified
mortar.
k) Polyer modified patching and adhesive repair mortar for beams &
columns.
(PCA.774.S034sca2) V.II-D2/S-III : 23