B 70
[Subsidiary]
Saving.
L.N. 294/76.
(Cap. 123, sub. leg.)
Reinforcement.
Minimum cover of reinforcement. L.N. 294/76.
CAP. 123] Building (Construction) Regulations
[1985 Ed.
(6) During erection the work shall be securely bolted or otherwise fastened, and if necessary temporarily braced, so as to make adequate provision for all erection stresses and conditions, including those due to erection equipment and its operation. Neither riveting, permanent bolting nor welding shall be done until proper alignment has been obtained.
(7) All structural steel at the site shall be stored and handled so that members are not subjected to excessive stresses and damage.
113. (1) Notwithstanding the provisions of regulations 97, 98 and 100, steel framed structures may be designed and constructed in accordance with the relevant provisions of BS 449:Part 2:1969:
Provided that the structural details and calculations required by regulation 8(1)(i) of the Building (Administration) Regulations shall be prepared and signed by a registered structural engineer.
(2) The registered structural engineer appointed for such design or his successor under section 4(2) of the Ordinance shall be responsible for the supervision of the structural work.
PART XII
STRUCTURAL USE OF REINFORCED CONCRETE
114. (1) Reinforcement shall be free from loose mill scale, loose rust, oil and other matter which might affect adversely its proper function with concrete.
(2) The effective diameter of a bar whose cross-section is constant along its length shall be the diameter of a circle having the same area as the cross-section of the bar.
(3) The effective diameter of a bar whose cross-section varies along its length shall be the diameter of a circle having an area equal to the least area of the bar. An allowance not exceeding 3 per cent may be added to the least area of the cross-section for any non-continuous ribs.
(4) Only one grade of deformed bars may be used on a site.
(5) (a) Mild steel and high-tensile or medium high-tensile steel for main reinforcement shall not be used together in the same member.
(b) For the purpose of this paragraph, "member" means any column, simple beam, continuous beam or slab.
115. (1) Subject to the provisions of Part XVI (Fire Resisting Construction) the minimum thickness of concrete cover to reinforcement (exclusive of plaster rendering or other applied covering or decorative finish) shall be—
(a) for each end of a reinforcement, not less than 25 mm or 2 times the diameter of that reinforcement, whichever is the greater;
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