PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

The contractor shall ensure that all reinforcing bars are thoroughly wire brushed and
cleaned free of loose mill scale, loose rust, coats and paints, oils, mud or other
coating.
Mesh reinforcement, where specified shall conform to IS:1566-1982.
Binding wire shall be annealed wire conforming to IS:280.
9.9 Cover.
Unless indicated otherwise, clear concrete cover for reinforcement (exclusive of
plaster or other decorative finish) shall be as follows:
(i) At each end of a reinforcement bar, not less than 25mm nor less than twice
the diameter of the bar.
(ii) For a longitudinal reinforcing bar in a column not less than 40mm, nor less
than the diameter of the bar. In case of columns of minimum dimension of
20cm or under with reinforcing bars of 12mm and less in dia. a cover of
25mm may be used.
(iii) For longitudinal reinforcing bars in a beam, not less than 25mm nor less than
the diameter of the bar.
(iv) For tensile, compressive, shear or other reinforcement in a slab, or wall, not
less than 15mm, nor less than the diameter of such reinforcement.
(v) For any other reinforcement, not less than 15mm, nor less than the diameter
of such reinforcement.
(vi) For footing and other principal structural members in which the concrete is
poured on a layer of lean concrete, the bottom cover shall be minimum of
50mm.
(vii) For concrete surfaces exposed to the weather or the ground after removal of
forms, such as retaining walls, grade beams, footing sides and tops, etc. not
less than 50mm for bars larger than 16mm diameter and not less than 40mm
for bars 16mm diameter or smaller.
GTS : General Technical Specification. Page 74