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    ASTM C956 - 04(2019)

    Standard Specification for Installation of Cast-In-Place Reinforced Gypsum Concrete

    Active Standard ASTM C956 | Developed by Subcommittee: C11.03

    Book of Standards Volume: 04.01

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    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.

    This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

    1. Scope

    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.

    1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    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 Standard

    ACI 318 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.

    ICS Code

    ICS Number Code 91.100.10 (Cement. Gypsum. Lime. Mortar); 91.100.30 (Concrete and concrete products)

    UNSPSC Code

    UNSPSC Code 11111601(Gypsum)

    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/C0956-04R19

    Citation Format

    ASTM C956-04(2019), Standard Specification for Installation of Cast-In-Place Reinforced Gypsum Concrete, ASTM International, West Conshohocken, PA, 2019, www.astm.org

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