Chapas dobradas a frio - Especificação

REFERENCE SECTION 5400, COLD-FORMED STEEL FRAMING

PART 1 - GENERAL

1.1 DESCRIPTION OF WORK

Furnish and install all cold-formed structural framing studs, tracks, joists, trusses, bracing, angles, plates, and related accessories indicated in the construction documents.

1.2 RELATED WORK SPECIFIED ELSEWHERE

Exterior sheathing per Division 7 “Exterior Insulation and Finish Systems” and Interior sheathing per Division 9 “Gypsum Sheathing”.

1.3 SUBMITTALS

The framing contractor shall be responsible for submitting part or all of the following items, as required by the construction documents:

1.3.1  Manufacturers technical literature covering product.

1.3.2  Manufacturers certification of product compliance with codes and standards.

1.3.3  Cold-formed structural framing calculations, as required.

1.3.4  Connection details, as required.

1.3.5  Shop drawings, as required.

1.3.6  Certification of the calculations, connections and or drawings by a registered professional engineer in the state where the project will be built, as required.

1.4 QUALITY ASSURANCE

The structural framing and its installation shall meet the following standards:

1.4.1  American Iron and Steel Institute (AISI) “Specification For The Design of Cold-Formed Steel Structural Members”, latest edition.

1.4.2  American Society for Testing and Materials (ASTM) Standard C 955 - Standard Specification for Load Bearing (Transverse and Axial) Steel Studs, Runners (Tracks), and Bracing or Bridging for Screw Application of Gypsum Board and Metal Plaster Bases.

1.4.3  ASTM Standard C 1007 - Standard Specification for Installation of Load Bearing (Transverse and Axial) Steel Studs and Related Accessories.

1.5  DELIVERY STORAGE & HANDLING

Upon delivery, the structural framing materials shall be protected from the elements by storing them in a sheltered area or using protective covers.

PART 2 - PRODUCTS

2.1 MANUFACTURERS

 

The cold-formed structural framing shall be called for in the contract documents and as furnished by Clark Steel Framing. Manufacturers submitting published data showing their product values to be equal to those published by Clark Steel Framing shall also be acceptable.

2.2 STRUCTURAL PROPERTIES

Structural framing stud, joist and track properties shall be as published by Clark Steel Framing. Equivalency shall be determined by published dimensional and structural properties including, but not limited to, section depth, flange size, lip size, design steel thickness, Cross sectional Area, effective Ix, and effective Sx.

2.3 MATERIALS

2.3.1  The cold-formed structural framing shall be manufactured from structural quality steel having minimum yield strength of 33 KSI (230 Mpa), for all gauges, or optional 50 KSI (345 Mpa) for 16 GA and heavier and have minimum protection coating equal to G-60 galvanized finish. The steel shall conform to one of the following ASTM Standards: ASTM A 653, ASTM A 875, ASTM A 792 or ASTM A 463.

2.3.2  The structural framing shall meet ASTM C 955, have engineering properties calculated in conformance with the AISI “ Specification for the Design of Cold-formed Structural Steel Members” and have minimum properties as published by Clark Steel Framing.

2.3.3  All structural framing accessories shall be formed from structural quality steel with minimum yield strength of 33 KSI (230 Mpa) and have minimum protective coating equal to G-60 galvanized finish.

2.4 FASTENING

2.4.1  Structural framing shall be properly spaced, plumbed, leveled, squared, fit properly against abutting members and held securely in place until permanently fastened. Wire tying of structural framing components is not permitted.

2.4.2  Fastening of the cold-formed structural framing system shall be accomplished by screwing, power actuated fasteners, welding or a combination of methods. The type, size and spacing of the fasteners shall be required by the contract documents or approved connection details.

2.4.3  Structural framing may be fastened in a shop or in the field.

2.4.4  Structural framing have protective coating removed by welding shall have the coating repaired, at the welds, by painting with a zinc rich primer.

PART 3 - EXECUTION

3.1 INSPECTION

Inspect supporting substrates and structure for compliance of proper conditions for installation and performance of the cold-formed structural framing.

3.2 PREPARATION

Prepare attachment surfaces so that they are plumb, level, and in proper alignment for accepting the cold-formed structural framing.

 

3.3 WALL FRAMING

3.3.1  Cold-formed structural framing may be shop or field fabricated into assemblies, prior to erection, or stick built in the field.

3.3.2  The structural framing members shall be sized, spaced and erected in accordance with the contract  documents or approved shop drawings.

3.3.3 The structural framing shall have ends squarely cut by shearing or sawing, be installed plumb, square, true to line and securely fastened per the contract documents or approved connection details.  Torch cutting is not permitted.

3.3.4  Fabrication, handling, and erection of the structural framing and assemblies shall be done in a manner to prevent any damage or distortion of the framing.

3.3.5  Cold-formed tracks, when set to adjacent structures, shall have web contact with a uniform and  level bearing surface and be securely anchored with fasteners, sized and spaced per the contract documents or approved connection details.