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37-R-5 Heavy Duty Riveted Carbon Steel Galvanized GratingsModel Specification for type 37-R-5 Carbon Steel Galvanized Grating as Manufactured by Direct Metals®, 3775 Cobb International Blvd. Kennesaw, GA 30152-4390 or approved equal. NOTE: The specifier will need to edit this specification to reflect the options in this document shown in Red. Some editing can be accomplished by deleting unnecessary requirements. For Heavy Duty Riveted Bridge Deck please contact Direct Metals for grating type recommendation based on the specific application SECTION 05 53 00 Metal Fabrications – Metal Gratings Part 1: General 1.1 Section Includes A. Prefabricated heavy duty riveted carbon steel bar gratings.B. Prefabricated Support Frames for gratings.C. Miscellaneous installation hardware and accessories.1.2 References A. ASTM A-36 Carbon SteelB. ASTM A-1011 CS Type B Steel Strip Hot-Rolled CarbonC. ASTM A-575 Carbon Steel RivetsD. ANSI/NAAMM- MBG-532-09 Heavy Duty Metal Bar Grating Manual1.3 Action Submittals A. Product Data: The contractor shall submit the manufacturer’s catalog pagesincluding load tables, anchor details and standard installation details.B. Shop drawings: The contractor shall submit for approval shop drawings for thefabrication and erection of all gratings, based on construction drawings of currentissue. Include plans, elevations, and details of sections and connections asrequired. Show type and location of all fasteners.C. Samples of Grating and Anchorage system shall be submitted for approval.1.4 Quality Assurance A. Manufacturer Qualification: A company specializing in the manufacture ofmetal bar gratings with not less than 10 years of documented experience.

B. Fabrication tolerances shall be in accordance with applicable provisions andrecommendations of ANSI/NAAMM 532-09 Metal Bar Grating Manual.Part 2: Products 2.1 Source Requirements: Design is based upon use of gratings as manufactured by Direct Metals® and terminology used herein may include reference to the specific performance or product of this manufacturer. Such reference shall be construed only as establishing the quality of materials, operational features and workmanship to be used under this Section and shall not, in any way, be construed as limiting competition. 2.2 Manufacturers: Acceptable Manufacturers include Direct Metals®, 3775 Cobb International Blvd. Kennesaw, GA 30152-4390, 800-711-4939, www.directmetals.com, or approved equal. 2.3 Manufactured Units: A. Description: Grating: Type 37-R-5 Heavy Duty Riveted Carbon Steel Gratingwith Galvanized finish. Manufactured by hydraulic compression of 3/8” diarivets to join heavy duty connecting bars 1-1/2” deep x 3/16” thick inreticuline fashion to heavy duty main bearing bars. Connecting bars areformed and punched for rivets 2-1/2” on center. Bearing bars are alsopunched to receive rivets 5” on center.1. Main Bearing Bar Spacing: 2-5/16” face to face.2. Bearing bar thickness: 1/4” (or 5/16” or 3/8”) as shown on thedrawings.3. Main Bearing Bar depth is to be based on loading requirementsand the clear span shown on the drawings.4. Connecting Bar 1-1/2” x 3/16” serrated and raised 1/8” above topsurface of main bars.5. Top of main bearing bars are to be smooth.6. Rivets 3/8” diameter and spaced 5” on center along main bearingbars.B. Fabrication: Load Band ends of grating with bars of same thickness as themain bearing bars. Weld banding flush with the top surface of the grating.Depth of banding to be ½” less than the depth of the main bearing bars asshown on the drawings. Include welded anchor blocks ¼” from the bottomsurface with hole to accept the specified attachment bolts with washers andnuts.C. Steel Frames: Carbon Steel ASTM A-36 frames shall be provided as shownon the contract drawings to support and attach the gratings. Include anchorsas shown for locking frame into concrete as shown on the plans. Galvanizeframes after fabrication per ASTM A123.

D. Design Criteria: 1. Loading: Unless shown otherwise on the contract drawings, gratings shall be designed and manufactured to meet the live load conditions of AASHTO HS 20 with 30% impact factor. Main Bearing bar depth shall be as shown on the contract drawings or as recommended by the manufacturer to meet the loading requirements, and clear span conditions. E. Materials: Main Bearing bars are to be ASTM A-36 Carbon Steel. Connecting bars are to be per ASTM A-1011 CS type B. Rivets are to be per ASTM A-575. Banding is to be Carbon Steel per ASTM A-36. F. Fabrication Tolerances shall be in accordance with ANSI/NAAMM MBG 532-09 Metal Bar Grating Manual. G. Finish: Gratings and frames shall be Hot-Dip Galvanized per ASTM A123 (or powder coat painted black as shown on the drawings). 2.4 Accessories: Provide appropriate fasteners for type, grade, and class required for the approved anchorage system. Part 3: Execution 3.1 Field Verification: Contractor is to provide field measurements prior to preparation of final shop drawings and fabrication where required to ensure proper fitting of the work. 3.2 Installation A. Prior to grating installation, contractor shall inspect supports for correct alignment and conditions for proper attachment and support of the gratings. Any inconsistencies between contract drawings and supporting structure deemed detrimental to grating placement shall be reported in writing to the Engineer, Architect or owner’s agent prior to placement. B. Install grating in accordance with shop drawings and standard installation clearances as recommended by ANSI/NAAMM MBG-532-09 Metal Bar Grating Manual. 3.3 Grating Attachment: Use approved attachment system and fasteners to secure grating to supporting members as shown on plans.