CSA S474-04 pdf free download

CSA S474-04 pdf free download.Concrete structures.
11.2.2
Tolerances for the buoyancy and stability of the structure afloat shall be set with due regard to the safety of the structure during all stages of construction and installation. In setting these tolerances, attention shall be given to the following factors, which can affect the draft and stability of the structure:
(a) the unit weight of the concrete and its variation over time due to absorption;
(b) the accuracy of the dimensions, in particular the thickness of walls and slabs;
(c) control of the overall configuration, particularly the radii of curvature of cylinders and domes, and prevention of distortion during casting;
(d) the weight and distribution of any permanent or temporary ballast, construction equipment, mooring lines, and material;
(e) the proper functioning of the system for varying the ballast when the structure is floating and sinking, including control of effective free water planes inside the structure;
(f) any loads added during construction; and
(g) the relative density of water, including variations caused by tidal and tributary sources at the construction and installation sites.
11.2.3
Unless otherwise specified by the designer, tolerances for vertically formed structures shall be as follows:
(a) The maximum out-of-plumb of any point of the structure with respect to the projection of a corresponding point at the base of the structure shall be not more than 75 mm in any 30 m of height or more than 100 mm total for a height over 30 m.
(b) For circular structures, variations from prescribed diameter or from true circular cross-section shall be not more than ± 25 mm, or ± 12 mm per 3.0 m of the diameter, whichever is larger, but in no case more than ± 75 mm.
(c) The variation from the prescribed inside width dimensions for non-circular structures shall be not more than ± 12 mm per 3.0 m of width or ± 50 mm in total.
(d) The variation from the prescribed wall thickness shall not exceed ± 10 mm.
11.3 Forms
11.3.1
Formwork and falsework, including design, material, construction preparation, inspection, and removal, shall be in accordance with Clauses 11.3.2 and 11 .3.3 of this Standard and CSA A23.1.
11.3.2
Form ties shall permit complete consolidation of concrete in and around the units so that leakage voids and honeycombing in the walls are prevented at these locations. Metal form ties shall have a minimum cover of 35 mm to all concrete surfaces. Tie holes shall be filled with well-bonded, dense, non-shrinking mortar and sealed to permanently prevent water or oil from entering the voids.CSA S474-04 pdf free download.