Active Standard ASTM C956 | Developed by Subcommittee: C11.03
Book of Standards Volume: 04.01
Historical (view previous versions of standard)
This specification covers the minimum requirements for the installation of cast-in-place reinforced gypsum concrete over permanent formboard. Subpurlins shall be designed to support live and dead loads of the roof deck. Got-rolled and cold-rolled steel shapes other than bulb trees or truss tees shall meet the requirements of this specification. Mineral fiber formborad shall be tested in accordance with the transverse loading test. Hexagonal reinforcing mesh, rectangular reinforcing fabric, gypsum concrete, and expansion filler strip shall be fabricated in accordance to the specification. The subpurlins shall be placed transversely to the purlins and primary framing and shall be spaced to suit the size of the formboards. Cross tees shall be provided where formboard ends are supported by purlins or the primary framing. Formboards shall be located face down on the flanges of the supporting members and with the ends on top of the purlins. The mesh of wire fabric shall be located with the main longitudinal wires at right angles to the subpurlins and adjacent to the formboard at midspan between the purlins. Expansion filler strips shall be placed continuously against the walls, curbs, nailers, or other rigid surfaces that gypsum concrete will abut. Gypsum concrete mixing and placement shall be performed. Mixing shall be thorough but not overmixed.
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1.1 This specification covers the minimum requirements for the installation of cast-in-place reinforced gypsum concrete over permanent formboard.
1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered requirements of the standard.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
A82/A82M Specification for Steel Wire, Plain, for Concrete Reinforcement
A185/A185M Specification for Steel Welded Wire Reinforcement, Plain, for Concrete
A568/A568M Specification for Steel, Sheet, Carbon, Structural, and High-Strength, Low-Alloy, Hot-Rolled and Cold-Rolled, General Requirements for
A653/A653M Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process
C11 Terminology Relating to Gypsum and Related Building Materials and Systems
C317/C317M Specification for Gypsum Concrete
C726 Specification for Mineral Wool Roof Insulation Board
E72 Test Methods of Conducting Strength Tests of Panels for Building Construction
American Concrete Institute StandardACI318 Building Code Requirements for Reinforced Concrete Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http://www.concrete.org.
American Welding Society StandardD1.1 Structural Welding Code Steel Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126, http://www.aws.org.
ICS Number Code 91.100.10 (Cement. Gypsum. Lime. Mortar); 91.100.30 (Concrete and concrete products)
UNSPSC Code 30111500(Concrete and mortars)