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PROFILES RHF
LLC
P O Box 656 - Sharjah - United Arab Emirates
Tel: +971 6 5342222 - Fax: +971 6 5342000
E-Mail : richard@profilesrhf.com
Web Site :http://www.profilesrhf.com
1. GENERAL
1.1 SCOPE:
1.1.1 The standard building scope of supply shall include the structural framing, metal roofing & sliding, bracing, doors, windows, insulation, hardware, fasteners, sealants and any other component parts for the metal building as specified or shown on the drawings.
1.1.2 All buildings shall have diagonal rod bracing in the roof, side walls, common walls between mail building and lean-to's, between interior columns under valley lines for multi span type buildings, unless othewise stated in PRH offer.
1.1.3 In the case of discrepancies, the provisions of the Final Order Acknowledgement Form shall govern unless agreed by Profiles RHF Ltd., in writing.
1.2 BUILDING NOMENCLATURE:
1.2.1 The building "width" and "length" shall be measured from inside to inside of wall covering.
1.2.2 The building eaveheight shall be measured from bottom of primary frame base plate to top of the eave strut. The top of the eave strut is the point of intersection between the inside surfaces of the wall and roof covering.
1.2.3 The bay spacing shall be measured as follows:
a. Interior bays from centre-line to centre-line of interior frames
b. End bays from inside of endwall sheets to centre-line of first interior frame.
1.3 DRAWINGS & CALCULATIONS:
The following shall be provided free of charge in 3 sets each after the receipt of the Final Order:
1.3.1 Anchor bolt setting plans will be provided by PRH or the franchised builder.
1.3.2 Erection drawings will be provided by PRH.
1.3.3 Preliminary drawings, design calculations and/or Letter of Certification for the structural framing and covering panels, signed by a Professional Engineer, may be submitted for client's approval upon request.
2. DESIGN
2.1 GENERAL:
2.1.1 All structural steel sections and welded plate members shall be designed in accordance with the applicable sections, relating to design requirements and allowable stresses, of the latest edition of the American Institute of Steel Construction "Specification for the Design, Fabrication and Erection of the Structural Steel for Buildings".
2.1.2 All light-gauge, cold formed, structural members and covering shall be designed in accorance with the applicable sections, relating to design requirements and allowable stresses, of the latest edition of the American Iron and Steel Institute "Specification for the Design of Cold Formed Steel Structural Members".
2.2 DESIGN LOADS:
2.2.1 Loads are applied as follows:
a. Live Load and Dead Load-applied to entire horizontal projection of the roof.
b. Wind Load-the wind load shall be applied in accordance with the Metal Building Manufacturers Association "Recommended Design Practices Manual". (Metal Building Manufacturers Association recommendations are based on the U.S.Department of the Navy publication, "NAVFAC DM-2 Design Manual"). Wind is applied to the primary members as either pressure or suction on the walls, and uplift or pressure on the roof. (Magnitude and direction is determined using factors based on shape coefficients times the basic wind pressure). The full specified wind pressure is applied to the secondary members as uplift on the roof, either pressure or suction on the walls; as well as on the wind bracing members.
2.2.2 Design load combinations:
a. Dead Load + Live Load
b. Dead Load + Wind Load
3. STRUCTURAL FRAMING
3.1 GENERAL:
3.1.1 All framing members shall be shop fabricated for bolted field assembly, unless otherwise noted on erection drawing.
3.1.2 All framing members shall be cleaned by power or hand-wire brushing to remove all dirt, grease, oil, loose mill scale, weld slag, flux deposit and other foreign matter, and given one shop coat of red oxide, air drying, phenol modified aikyd resin prime. Primer shall equal or exceed the end performance requirements of U.S. Federal Specification TTP-636.
3.2 PRIMARY MEMBERS:
3.2.1 Primary structural framing shall refer to the transverse rigid frames, lean-to rafters and columns, canopy rafters, interior columns (beam and column frames) bearing frame rafters and corner columns, and endwall wind columns.
a.. Members fabricated from plate or bar stock shall have flanges and webs joined on one side of the web by a continuous welding process. This plate or bar stock shall have a minimum yield strength of 290 MN1m2 (42,000 psi) and will conform to the physical specifcations of either:
1) 290 MN/m (42,000 psi) - ASTM A572 (Grade 42) or equivalent.
2) 345 MN/m2 (50,000 psi) - ASTM A572 (Grade 50) or equivalent.
b. Members fabricated by cold forming process shall have a minimum yield strength of 345 MN/m2 (50,000 psi) and will conform to the physical specifications of ASTM A-607 (Grade 50) or equivalent.
c. Members fabricated from hot rolled structural shapes shall have a minimum yield strength of 250 MN/m2 (36,000 psi)
3.3 SECONDARY MEMBERS:
3.3.1 Secondary structural framing shall refer to purlins, girts, eave struts, wind bracing, flange brading, base angles, clips and other miscellaneous structural parts:
a. Purlins, girts and eave struts shall be cold formed from steel which has a minimum yield strength of 345 MN/m2 (50,000 psi) and will conform to the physical specifications of ASTM A-607 (Grade 50) or equivalent.
b. Rod bracing shall have a minimum yield strength of 250 MN/m2 (36,000 psi) and will conform to the physical specifications of ASTM A-36 or equivalent.
c. All other miscellaneous secondary members shall have a minimum yield strength of 250 MN/m2 (36,000 psi)
3.4 CONNECTIONS:
3.4.1 All field connections shall be bolted (unless otherwise noted)
a. All primary based connections, as shown on drawings, shall be furnished with high strength bolts conforming to the physical specifications of ASTM A-325 (or equivalent). All high strength bolts, nuts and washers shall be zinc plated.
b. All secondary bolted connections, as shown on drawings, shall be furnished with machine bolts conforming to the physical specifications of ASTM A-307 (or equivalent). Machine bolts, nuts and washers will be zinc plated.
3.4.2 All shop connections shall be welded using either submerged or shielded are process, and welding shall be in accordance with the applicable sections, relating to design requirements and allowable stresses, of the latest editions of the American Welding Society "Structural Welding Code".
4. ROOF AND WALL COVERING
4.1 GENERAL:
4.1.1 Typical roof, wall and liner panels shall be color coated, 26 gauge, galvanised steel, ribbed panels (Other materials and thickness available upon request).
4.2 PANEL MATERIALS:
4.2.1 Base material for color coated galvanised steel panels shall have a minimum yield strength of 265 MN/m and will conform to the physical specifications of ASTM A-527 or equivalent.
4.2.2. The zinc coating is a hot dip galvanisation process conforming to ASTM Specification A-525 with a coating class of G-60 or its equivalent.
4.2.3 The painting shall be baked enamel polyester (white) with a film thickness of 20 microns. The reverse side shall be white with 10microns film thickness.
4.3 FASTENERS:
4.3.1 Standard fasteners shall be No.14, Type A, self tapping sheet metal screws with metal and neoprene washers, which conform to American Standards Associatin Specifications. All screws shall have hex heads, be colour coated to match roof or wall panels and shall be plated steel.
4.4 SEALER:
4.4.1 Sealer for sidelaps, endlaps and self-flashing windows shall be 9mm wide x 2.5 mm thick, blend of cross-linked butyl and inert fillers extruded into strip or bead to form a roll, with paper backing.The sealer shall be non-hardening, permanently flexible, no fumes, solvent free have superior adhesion to metals, plastics and painted surfaces at temperatures from -40 deg.C to +90 deg.C.
4.5 FLASHING, TRIM AND CLOSURES:
4.5.1 Flashing and/or trim shall be furnished at the rake, corners, eaves, framed openings, and wherever necessary provide weather tightness and finished appearance. Colour shall be selected from PRH, standard colours, with the exception of the corner trim, which matches the building wall colour.
4.5.2 Colour coated, galvanised steel for flashing, metal closure, trim and other miscellaneous uses shall be 26 gauge of the same specification as the roof and walls covering material.
4.5.3 A formed peak panel matching the slope and profile of adjoining panels shall be provided along the building ridge.
4.5.4 Fully closed cell cross linked polythylene foam closure matching the profile of the panel shall be installed along the eave, rake and other locations specified on PRH drawings.
4.6 COLOUR FINISH:
4.6.1 Unless specified otherwise, all wall and roof panels, flashing, trim and other exposed galvanised steel surfaces shall be colour coated.
a. Colour of panels and corner trim shall be selected by the customer from PRH standard colours.
b. The gutters, downspouts, rake trim, eave trim and door flashing shall be white unless otherwise selected from PRH standard colours.
5. BUILDING ANCHORAGE AND FOUNDATIONS
5.1 ANCHORAGE
5.1.1 The building anchor bolts shall be designed to resist the column reactions resulting from the specified load (combined shown in sectin 2). The bolt sizes shall be as specified on the drawings, but shall not be furnished PRH.
5.1.2 The building foundation and related anchorage shall be designed by a qualified engineer (not by PRH) to support the building's reactions, in addition to other loads imposed by the building's use or occupancy. This design shall be based on actual jobsite conditions.
6. REFERENCES
6.1 Following are specifications, and/or codes, to which PRH buildings are designed and/or fabricated (See specifications for particular sections of each to which buildings or products conform).
6.1.1 American Institute of Steel Construction (AISC) "Steel Constructiion Manual".
6.1.2 American Iron and Steel Institute (AISI) "Specification for the Design of Cold Formed Steel Structural Members".
6.1.3 Metal Building Manufacturers Association (MBMA) "Recommended Design Practices Manual".
6.1.4 U.S.Department of Navy Publications "NAVFAC DM-2 Design Manual".
6.1.5 American Society for Testing and Materials (ASTM)
6.1.6 American Standards Association Specification (ASA)
6.1.7 American Aluminiukm Manufacturer's Association (AAMA)
DATA SHEET - PROFILED ALUMINIUM PANELS
Aluminium alloy, used in the production of profiled roof and wall cladding panels, is AA 3105, which conforms to BS 4300/6 Alloy NS31, and DIN 1725 Alloy AL Mn 0.50 mg 0.50.
Material Properties Ultimate Strength: Min 200 N/mm2 yield strength: Min 180 N/mm2 Modules of elasticity : 70000 N/mm2 Coef. of thermal expansion : 24 x 10-6
Durability When exposed to the atmosphere natural aluminium forms a thin layer of protective oxide coating on tis surface. Thanks to this composition, the roofing element is adequately protected against corrosion undeer normal conditions of exposure to atmospheric conditions, especially in coastal and industrial area.
Fire: Aluminium is classified as a non-combustible material, as defined by BS 476:part 4:1970. Roof coverings of aluminium alloy are rated EXT AA when tested in accordance with BS 476: part 3:1958.
Combining with other material, these roof coverings can come into direct contact with plastics, galvanized steel, high-grade and pre-painted steel and zinc sheets.
Direct contact with ordinary steel, copper, brass and lead should be avoided by introducing a continuous seperating element such as PVC tape, or bitumen felt strips, or, alternatively, painting with zinc chromate or aluminium paint. This also applies to direct contact with mortar and concrete.
Timber parts which come into contact with aluminium should be treated with impregnating agents which do not contain copper salts, mercury salts, phenol compounds or fluorine compounds.
Finishes Mill Finish:This is the natural untreated surface of the metal as it leaves the rolling mill.
Stucco-embossed aluminium is mill-finished aluminium. This is roller-embossed to produce an irregular raised pattern finish. The advantage of embossing is that direct reflections and sun glaze are diffused, without reduction in the total reflectivity.
Polyester colour-coated an economical, long-life coating, factory applied polyester on the exposed side, and a lacquer coating on the reverse side. This is available in RAL as well as BS colour shades.
PVF2 colour-coated excellent U.V.resistance, long-life coating of 2 coats of factory applied PVF2 on the exposed side and a lacquer coating on the reverse side. Available in RAL as well as BS colour shades.
DATA SHEET - PROFILED STEEL PANELS
Alloy the base material shall conform to ASTM A527 (Lock Forming Quality) or structural quality ASTM A446 Grade D (Yield stress of 345 N/mm2)
Finishes Plain Galvanized the base steel material is hot dipped galvanized Zinc coating thickness as per ASTM A525-G90 or G60 (Zinc coating 275 g/m2 or 180 grs/m2 total both sides).
AL-Zn coated the base material is coated in AN150 (150g/m2 of Aluminium Zinc coating). This coating offers superiod corrosion resistance as compared to galvanized sheet.
Paint Finishes (Applies for galvanized as well as Alu-Zinc).
Polyester an economical long life coating. External side coated in 20 microns polyester and internal side coated in 10 microns primer. Available in BS and RAL colour shades.
PVF2 this coating has high resistance to fading due to excellent UV resistance. Available in BS and RAL colour shades.
PVC Plastisol this coating has an excellent resistance to mechanical damage and has good enough anti-fading properties. This coating is used in a thickness of 200 microns.