Amendment -02 05500-081209.pdf

Modernization of the South Building US Department of Agriculture Contract No. 53-3142-4-6049

Addendum #2 August 12, 2009 Bid Set 05500- 1 Metal Fabrications

SECTION 05500

METAL FABRICATIONS

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. Description of Work: Work of this Section includes, but is not limited to, the following:

1. Metal fabrications made from iron and steel shapes, plates, bars, strips, tubes, pipes and castings which are not part of ornamental metal or other metal systems specified elsewhere.

2. Miscellaneous framing and supports.

3. Steel framing for precast concrete vault covers.

4. Steel stairs.

5. Steel stair gate and window guardrail.

6. Steel railings and handrails, including extensions of existing guardrails and newell posts.

7. Steel lintels.

8. Stair nosings.

9. Steel ladder.

10. Steel safety cages at existing steel ladders.

1.3 RELATED WORK SPECIFIED ELSEWHERE

A. See Section 01120 CONSTRUCTION IAQ MANAGEMENT for managing indoor air quality during construction.

B. See Section 01352 LEED REQUIREMENTS for sustainable design requirements and procedures, including submittal requirements.

C. See Section 01572 CONSTRUCTION WASTE MANAGEMENT for managing construction waste.

D. See Section 03310 CAST-IN-PLACE CONCRETE for precast concrete removable vault covers.

E. See Section 05120 STRUCTURAL STEEL.

F. See Section 05700 ORNAMENTAL METAL for ornamental fabrications.

Addendum #2 August 12, 2009 Bid Set 05500- 2 Metal Fabrications

G. See Section 05910 METAL CLEANING AND REFINISHING for treatment of existing ornamental metal.

H. See Section 07720 ROOF ACCESSORIES for roof hatch equipment.

I. See Section 09900 PAINTING AND FINISHING for field applied painting systems.

1.4 SUBMITTALS

A. Professional Certification: Provide Shop Drawings and engineering calculations prepared and sealed by a Registered Professional Engineer, licensed in Project jurisdiction, for guardrails and stairs.

B. Product Data: Submit manufacturer's specifications and installation instructions for products used in miscellaneous metal fabrications, including paint products and grout.

C. Shop Drawings:

1. Submit Shop Drawings for fabrication and erection of miscellaneous metal fabrications.

2. Include plans, elevations and details of sections and connections, including location of shop and field connections and locations and details of anchors and base plates.

3. Indicate welded connections with AWS A2.0 welding symbols. Indicate net weld lengths.

4. Show anchorage and accessory items.

5. Survey field conditions and verify dimensions before submitting.

D. Calculations: Submit, for information only, engineering calculations for guardrails and stairs.

E. Certificates: Provide welder's certificates for welders employed on Work, verifying AWS qualifications within previous 12 months.

F. Qualification Data: Submit fabricator and installer qualifications verifying years of experience; include list of completed projects having similar scope of work identified by name, location, date, reference names and phone numbers.

G. Design Modifications:

1. Submit for review any proposed variations in details or substitutions in materials required to meet specified performance requirement or to coordinate Work.

2. Design modifications must be prepared and sealed by a Registered Professional

Engineer, licensed in Project jurisdiction with calculations to support the proposed modification.

1.5 DEFINITIONS

A. Guardrail: A system of building components located near open sides of elevated walking surfaces for purpose of minimizing possibility of accidental fall from walking surface to lower level.

Addendum #2 August 12, 2009 Bid Set 05500- 3 Metal Fabrications

B. Handrail:

1. Horizontal or sloping rail grasped by hand for guidance or support, and for arresting falls on adjacent walking surface.

2. Handrails may form part of a guardrail system.

1.6 SYSTEM REQUIREMENTS

A. Design Requirements:

1. Use materials of size and thickness indicated or, if not indicated, as required to produce strength and durability in finished product for use intended.

2. Design and fabricate components to support loads indicated or required to comply with requirements of authorities having jurisdiction over Project.

3. Design modifications:

a. May be proposed by manufacturer to satisfy performance requirements.

b. Must conform to design and specified durability and strength.

c. Must maintain profiles and alignments indicated.

B. Structural Requirements:

1. Treads, platforms, and gratings: Capable of withstanding uniform load of 4.8kPa, or concentrated load of 1.3kN applied at any point, whichever produces the greater stresses.

2. Handrails:

a. Capable of withstanding concentrated load of 200 lb-f (890 N) applied in any direction at any point along the top, and uniform load of 50 lb-f/lf (730 N/m) applied in any direction at the top, when tested according to ASTM E935.

b. Do not assume uniform and concentrated loads act concurrently.

3. Guardrails:

a. Toprails:

1) Capable of withstanding concentrated load of 200 lb-f (890 N) applied in any direction at any point along the top, and uniform load of 50 lb-f/lf (730 N/m) applied in any direction at the top, when tested according to ASTM E935..

2) Do not assume uniform and concentrated loads act concurrently.

b. Intermediate rails/infill area: Capable of withstanding horizontal concentrated load of 50 lb-f (220 N) applied on a 1 square foot (.09 square meters) area at any point, including intermediate rails or similar elements.

4. Ladders: Conform to OSHA requirements, and ANSI A17.1 for elevator pit ladders.

C. Visual Requirements: For metal fabrications exposed to view, use materials which are smooth and free of surface blemishes including pitting, seam marks, roller marks, rolled trade names and roughness.

D. Interface With Other Systems:

1. Coordinate and furnish anchorages, setting drawings, diagrams, templates, instructions and directions for installation of anchors.

2. Coordinate delivery of such items to Project site.

3. Coordinate primers with finish paint and touch-up fireproofing.

Addendum #2 August 12, 2009 Bid Set 05500- 4 Metal Fabrications

1.7 QUALITY ASSURANCE

A. Fabricator and Installer Qualifications: Not less than 5 years documented, successful experience with work comparable to Work of this Project.

B. Designer/Engineer Qualifications: Modifications designed under direct supervision of a Registered Professional Engineer, licensed in Project jurisdiction.

C. Welder Qualifications: AWS certified for type of welding required.

D. Regulatory Requirements: Conform to applicable requirements of authorities having jurisdiction over Project.

E. NAAMM Stair Standard: Comply with "Recommended Voluntary Minimum Standards for Fixed Metal Stairs" in NAAMM AMP 510, "Metal Stairs Manual," for class of stair designated, unless more stringent requirements are indicated.

1.8 PROJECT CONDITIONS

A. Field verify dimensions of supporting structure and other adjoining elements before submitting shop drawing. Government will not review or take responsibility for dimensions.

PART 2 - PRODUCTS

2.1 MATERIALS

A. Environmental Requirements:

1. Recycled Content: Give preference to products with maximum recycled content possible.

2. Regional Materials: Give preference to products that have been manufactured within

800 km (500 miles) of Project site from materials that have been extracted, harvested, or recovered, as well as manufactured, within 800 km (500 miles) of Project site.

3. See Section 01352 LEED REQUIREMENTS for VOC requirements for paints and primers.

B. Metal:

1. Where new Work is an extension of existing components, match existing material, profile and configuration.

2. Structural steel plates, shapes and bars: ASTM A36.

3. Steel tubing: Cold formed, ASTM A500, grade selected by fabricator to suit Project conditions; or hot rolled, ASTM A501.

4. Steel bars: ASTM A108, ASTM 29, ASTM A575 or ASTM A576, type and grade selected by fabricator to suit Project conditions.

5. Steel pipe: ASTM A53; type and grade selected by fabricator to suit Project conditions.

Addendum #2 August 12, 2009 Bid Set 05500- 5 Metal Fabrications

6. Brackets, flanges and anchors: Cut or formed metal of same material and finish as supported units, unless otherwise indicated.

7. See Section 01352 LEED REQUIREMENTS for recycled steel content requirements.

C. Primers:

1. Ferrous metal - typical painting systems: Universal shop primer; fast-curing, lead- and chromate-free, universal modified-alkyd primer complying with MPI#79.

2. Ferrous metal - polyurethane coating system:

a. Moisture-cure organic zinc-rich primer complying with SSPC-Paint 20 or SSPC-Paint 29 and compatible with topcoat.

b. Acceptable products and manufacturers:

1) Carbozinc 684 by Carboline Company.

2) Ganicin 2.8 MCZ by Dupont Company.

3) 90-97 Tneme-Zinc by Tnemec Company, Inc.

D. Galvanizing Repair Paint: High zinc-dust content paint complying with SSPC Paint 20.

E. Bituminous Paint: Cold-applied asphalt-mastic paint complying with SSPC-Paint 12 requirements except containing no asbestos, formulated for 30 mil thickness per coat.

F. Grout: Non-shrink grout; factory-packaged, non-staining, non-corrosive, non-gaseous grout complying with ASTM C1107; specifically recommended by manufacturer for both interior and exterior applications.

G. Concrete Fill: See Division 03 Section CAST-IN-PLACE CONCRETE.

2.2 ACCESSORIES

A. General:

1. Unless otherwise indicated, provide Type 304 stainless-steel fasteners for exterior use and zinc-plated fasteners with coating complying with ASTM B633, Class Fe/Zn 5, at exterior walls.

2. Provide stainless-steel fasteners for fastening aluminum.

3. Select fasteners for type, grade, and class required.

B. Fasteners and Anchors:

1. Select fasteners of type, grade and class required, unless otherwise noted.

2. Bolts: Regular hexagon head type, ASTM A307, Grade A.

3. Nuts: ASTM A563, Grade A.

4. High strength fasteners:

a. Bolts: ASTM A325, Type 1.

b. Nuts: ASTM A563, Grade C, heavy hex.

c. Washers: ASTM F436, hardened.

5. Lag bolts: Square head type, FS FF-B-561.

6. Machine screws: Cadmium plated steel, FS FF-S-92.

7. Plain washers: Round, carbon steel, FS FF-W-92.

Addendum #2 August 12, 2009 Bid Set 05500- 6 Metal Fabrications

8. Expansion bolts: Toothed steel or lead shield expansion devices of type and size indicated, with galvanized bolts; FS FF-S-325, Group II, Type 4, Class 1 for concrete expansion bolts. Do not use lead shield bolts for overhead installations.

9. Toggle bolts: Tumble-wing type, FS FF-B-588, type, class and style as required.

10. Lock washers: Helical spring type carbon steel, FS FF-W-84.

11. Powder driven anchors:

a. Type and size indicated or, if not indicated, comply with manufacturer's standards.

b. Use devices and tools which comply with ANSI A10.3.

c. Do not use powder driven anchors as suspension member anchors.

12. Heavy duty adhesive anchors: Anchoring system composed of bolt and threaded rod, internally threaded insert and adhesive capsules, sized as required and recommended for substrate and condition.

C. Welding Materials: AWS D1.1; type required for materials being welded.

2.3 FABRICATION

A. Assembly:

1. Pre-assemble items in shop to greatest extent possible.

2. Disassemble units as necessary for shipping and handling limitations.

3. Clearly mark units for re-assembly and coordinated installation.

B. Fabricate Work to dimensions indicated or accepted on Shop Drawings.

C. Forming:

1. Form exposed Work true to line and level with accurate angles and surfaces and straight sharp edges.

2. Ease exposed edges to radius of approximately 0.8 mm unless otherwise indicated.

3. Form bent-metal corners to smallest radius possible without causing grain separation or otherwise impairing Work.

4. Form exposed connections with hairline joints, flush and smooth, using concealed fasteners wherever possible.

D. Anchors and Fasteners:

1. Provide for required anchorage, coordinated with supporting structure.

2. Fabricate and space anchoring devices to provide adequate support for intended use.

3. Cut, reinforce, drill and tap metal fabrications as indicated to receive hardware and similar items.

4. Use exposed fasteners of type indicated or, if not indicated, Phillips flathead

(counter-sunk) screws or bolts.

2.4 SHOP FINISHING

A. Galvanizing:

1. Complete shop fabrication prior to application of coating.

2. Remove mill scale and rust, clean and pickle units as required.

Addendum #2 August 12, 2009 Bid Set 05500- 7 Metal Fabrications

3. Apply galvanized coating in accordance with the following:

a. ASTM A153 for galvanizing iron and steel hardware.

b. ASTM A123 for galvanizing rolled, pressed and forged steel shapes, plates, bars and strip 3 mm thick and heavier.

c. ASTM A653 for galvanizing steel sheet, G90 coating.

4. Coating weight: Conform with Table 1 of ASTM A153, as appropriate.

5. Provide post-galvanizing treatments as recommended by AGA for conditions applicable to Work. Do not quench or apply post galvanizing treatments that might interfere with paint adhesion.

B. Shop Painting:

1. Clean, treat and paint metal fabrications in shop prior to delivery to site.

2. Prepare all surfaces, inside and out, whether exposed or concealed in Work.

3. Shop prime structural steel members except areas or surfaces of members that will be field welded.

4. Fully concealed items:

a. Clean Work by SSPC-SP1 "Solvent Cleaning", followed by SSPC-SP2 "Hand Tool Cleaning".

b. Apply prime coat as soon as possible after cleaning. Provide smooth, uniform dry film thickness of 2.0 mils.

5. Exposed interior items: Clean and treat as specified for "Fully Concealed Items", except remove mill scale and rust that would result in visible surface roughness to provide smooth surface.

2.5 COMPONENTS

A. Miscellaneous Framing and Supports, and Structural Steel Framing and Reinforcing:

1. Provide miscellaneous steel and structural steel framing and supports, as required to complete Work.

2. Fabricate from structural steel shapes and plates and steel bars, of welded construction using mitered joints for field connection, unless otherwise indicated.

3. Cut, drill and tap units to receive hardware and similar items.

4. Space anchors at 600mm on center. Provide minimum anchor units of 30 mm x 6 mm x 200mm steel straps, unless otherwise indicated.

5. Where required by details or conditions, and not otherwise indicated, provide welded or bolted structural steel assemblies above suspended ceilings and connect to structure to provide rigid assembly.

6. Finish: Prime painted.

B. Steel Lintels:

1. Furnish loose structural steel lintels for openings in masonry walls as indicated on

Drawings.

2. Size to provide not less than 200mm bearing on each side, unless otherwise indicated.

Fabricate lintels in single lengths over each opening; do not locate end joints in lintels over openings.

3. Finishes:

a. Exterior walls: Galvanized.

b. Interior walls: Prime painted.

Addendum #2 August 12, 2009 Bid Set 05500- 8 Metal Fabrications

C. Steel Framed Stairs:

1. Construct stairs to sizes and arrangements indicated. Pre-engineered stairs are not acceptable.

2. Join pieces by welding, unless otherwise indicated.

3. Provide complete stair assemblies, designed to support stairs and platforms and capable of anchoring and containing stairs on supporting structure and conforming to structural requirements.

4. Stair framing - Typical:

a. Stringers: Structural steel channels as indicated and as specified in Section 05120

STRUCTURAL STEEL. Provide closures for exposed ends of stringers.

b. Platforms: Structural steel channel headers and framing members indicated.

c. Risers, subtreads and subplatforms: Structural steel sheet shaped to conform to profiles indicated with thickness sufficient to support design loading; minimum 1.9mm thick.

d. Metal pans: Cold-rolled carbon sheet steel, minimum 1.9mm thick.

5. Connections:

a. Bolt or weld headers to stringers and framing members.

b. If bolts are used, fabricate and join so that they do not appear on finish surfaces.

c. Directly weld risers and treads to steel angle supports and stringers. Grind welds smooth.

6. Finishes:

a. Typical: Prime painted.

D. Steel Pipe Railings and Handrails:

1. Conform to design, dimensions and details indicated.

2. Material: Steel pipe of sizes and wall thicknesses indicated, or if not indicated, as required to support design loading.

3. Forming:

a. Form bends by use of prefabricated elbow fittings and radius bends or by bending pipe.

b. Form simple and compound curves by bending pipe in jigs to produce uniform curvature for each repetitive configuration required; maintain cylindrical cross-section of pipe throughout entire bend without buckling, twisting or otherwise deforming exposed surfaces of pipe.

4. Connect pipe with prefabricated elbow fittings or flush radius bends.

5. Provide wall returns at ends of wall-mounted handrails, unless otherwise indicated.

6. Close exposed ends of pipe by welding 4.5 mm thick steel plate in place or by use of prefabricated fittings.

7. Brackets, flanges, fittings and anchors:

a. Provide wall brackets, end closures, flanges, miscellaneous fittings and anchors for interconnections of pipe and attachment of railings and handrails to other Work.

b. Furnish inserts and other anchorage devices for connecting railings and handrails to concrete or masonry Work.

c. Pipe sleeves: Galvanized steel pipe not less than 150 mm long with inside diameter not less than 12mm greater than outside diameter of insert.

Addendum #2 August 12, 2009 Bid Set 05500- 9 Metal Fabrications

d. Toe boards: Provide toe boards at railings around openings and at edges of open-sided floors and platforms, minimum 100mm high, unless otherwise indicated.

8. Finish:

a. Interior railings - Typical: Prime painted.

b. Exterior railings: Galvanized.

E. Handrail Brackets and Post Caps:

1. Fabrication: Cast from malleable iron.

F. Stair Gates:

1. Fabricate from steel pipe to dimensions and details indicated with smooth bends and welded joints ground smooth and flush.

2. Hardware:

a. Hinges: Provide minimum three cam-type self-closing hinges; number as required to support gate. Spring hinges are not acceptable.

b. Stop: Steel plate stop with bumper silencer.

3. Anchor assembly to steel tube, anchored to steel anchor plate concealed in wall assembly.

4. Finish: Prime painted.

G. Window Guardrail:

1. Fabricate from steel components indicated to dimensions and details indicated with smooth bends and welded joints ground smooth and flush.

2. Finish: Prime painted.

H. Stair Nosings:

1. Cast iron units of size indicated, with anchorage required for secure attachment to the substrate flush with adjacent floor or tread surfaces.

2. Wearing surface: Diamond pattern with aluminum oxide grains integrally cast into surface.

3. Metal color: Black shop-applied paint by manufacturer.

I. Aluminum Traction Treads: Clear finish.

J. Steel Ladders:

1. Comply with requirements of ANSI A14.3 and fabricate as follows, unless otherwise indicated.

2. Side rails: Continuous structural steel flat bars with eased edges. Provide profiles, sizes and spacings as indicated.

3. Rungs:

a. Solid structural steel bars. Provide profiles, sizes and spacings as indicated.

b. Fit rungs in centerline of side rails, plug weld and grind smooth on outer rail faces.

4. Supports:

a. Support each ladder at top and bottom and at intermediate points spaced not more than 1.5 m on center.

Addendum #2 August 12, 2009 Bid Set 05500- 10 Metal Fabrications

b. Use welded or bolted steel brackets, designed for adequate support and anchorage, and to hold ladder minimum 175 mm clear from wall to centerline of rungs.

c. Extend rails 1070 mm above top rung, and return rails to wall or structure unless secure handholds are provided.

5. Provide non-slip surface on top rung, either by coating rung with aluminum oxide granules set in epoxy resin adhesive or by using type of manufactured rung filled with aluminum oxide grout.

6. Finish: Prime painted.

K. Safety Cages:

1. Provide for at existing steel ladders with greater than 6080 mm run as follows:

a. Fabricate from welded steel bars.

b. Top, bottom and intermediate hoops: 7.8 mm x 100 mm bars at 6080 mm on center maximum.

c. Vertical bars: 7.8 mm x 50 mm bars at 225 mm on center maximum, secured to hoops.

d. Additional horizontal hoops: 7.8 mm x 50 mm bars at maximum 1200 mm on center.

e. Fasten safety cage to ladder rails and adjacent construction.

2. Finish: Galvanized.

L. Manhole Cover:

1. Description: Provide hinged aluminum manhole cover assembly.

2. Cover: Aluminum tread plate, 6 mm thick.

3. Cover Reinforcement: As required by product manufacturer.

4. Frame: Extruded aluminum alloy 6061-T6 heat treated, all welded construction.

5. Safety features:

a. Flush mounted hinges.

b. Flush mounted padlock cover.

c. Recessed padlock pocket.

d. Door brace rod.

6. Mountings: Flush.

7. Door Size: 610 mm x 610 mm square.

8. Frame size: 768 mm x 768 mm square (outside dimension)

9. Finish: mill finished aluminum.

M. Precast Concrete Vault Covers:

1. Provide continuous steel channel framing for precast concrete fixed and removable vault covers.

2. Sizes and profiles: As indicated.

3. Frame corners: Mitered and fully welded.

4. Finish: Galvanized (after installation of headed studs).

5. See Section 03310 CAST-IN-PLACE CONCRETE for precast concrete vault covers.

Addendum #2 August 12, 2009 Bid Set 05500- 11 Metal Fabrications

PART 3 - EXECUTION

3.1 EXAMINATION

A. Examine substrates and adjoining construction, and conditions under which Work is to be installed. Do not proceed with Work until unsatisfactory conditions are corrected.

3.2 PREPARATION

A. Temporary Shoring and Bracing:

1. Provide temporary shoring and bracing members with connections of sufficient strength to bear imposed loads.

2. Do not remove temporary members and connections until permanent members are in place and final connections are made.

3.3 INSTALLATION

A. Install components in accordance with manufacturer's instructions and final Shop Drawings.

B. Cutting, Fitting and Placement:

1. Cut, drill and fit metal fabrications as required.

2. Set Work accurately in location, alignment and elevation, plumb, level, true and free of rack, measured from established lines and levels.

3. Fit exposed connections accurately together to form tight hairline joints.

4. Do not field cut or alter structural members without approval of Government.

C. Fastening:

1. Secure metal fabrications to in-place construction by using threaded fasteners for concrete and masonry inserts, toggle bolts, through-bolts, lag bolts, wood screws and other connectors as required.

2. Anchor securely as required for intended use, using concealed anchors wherever possible.

3. Do not use powder driven anchors if safety hazard exists.

4. Complete field connections before load is applied.

D. Welding:

1. Comply with AWS Code for procedures of manual shielded metal-arc welding, appearance and quality of welds made, and methods used in correcting welds.

2. Field weld components indicated on final Shop Drawings.

3. Grind exposed joints smooth and touch-up shop paint coat.

E. Setting Loose Lintels: See Section 04210 UNIT MASONRY.

F. Steel Pipe Handrails:

1. Adjust railings prior to anchoring to ensure matching alignment at abutting joints.

2. Weld or otherwise attach newel post extensions and guardrails to existing components so that new Work matches existing.

3. Posts anchored to steel: Provide welded connections, unless otherwise indicated.

4. Rails: Unless otherwise indicated, weld rails to posts.

Addendum #2 August 12, 2009 Bid Set 05500- 12 Metal Fabrications

5. Wall brackets and flanges:

a. Connect brackets and flanges to rails.

b. Anchor wall brackets and flanges to concrete and masonry with bolts and expansion shields.

c. Anchor brackets and flanges in drywall by means of toggle bolts.

d. Build extended brackets into masonry and bolt bearing plate to concrete masonry.

3.4 ADJUST AND CLEAN

A. Touch-Up Painting:

1. Immediately after erection, clean field welds, bolted connections and abraded areas of shop paint.

2. Paint exposed areas with same material used for shop painting, except provide different color.

3. Provide minimum dry film thickness of 2.0 mils.

B. For Galvanized Surfaces: Clean field welds, bolted connections and abraded areas and repair in accordance with ASTM A780.

END OF SECTION