2017-06-26-minutes-public-works-study-session

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9.0 MATERIALS OF CONSTRUCTION 9.1 Structural Steel For weathering steel bridges, all structural steel shall be ASTM A588. 9.2 Deck Material Decking to be 4.25 -inch Steel Bridge Deck, 9 -gage, placed transverse across the width of the bridge. The height of the deck shall be 4.25" from top of the lower through to top of the profile. Width of the plank shall be 12-13116" with one 13/16" overlapping leg. Decking shall be manufactured from pre -galvanized steel, ASTM A653 Grade 50 Class with a minimum 2 oz. galvanized coating, Fy--50 ksi. Decking is to be welded to top flange of stringers and to adjoining sheets. Welds to be treated with organic zinc -rich coating meeting the material and performance requirements of ASTM A 780 (Standard Practice for Repair of Damaged and Uncoated Areas of Hot -Dip Galvanized Coatings). 9.3 Wearing Surface Timber (Treated) - Running (Ribbon) Top of side dam shall be 3.5" above top of 4.25 -inch Steel Bridge Deck for timber wearing surface. Timber wearing surface shall be two ribbons of tour planks each of 3x12 No. 2 or better, rough sawn, West Coast Region Douglas Fir, pressure treated ACQ or equal to 0.4 pct or refusal. Timber shall be attached to the 4.25 -inch Steel Bridge Deck utilizing'/" diameter galvanized carriage bolts, two at each end of the planks and one alternating every 4'-0" along the length of the planks. Some planks will be shipped loose to allow access to the lifting lugs and the bolted stitch connection. 9.4 Fasteners Structural bolts used to field splice, or connect; all main members shall be ASTM A325, in accordance with the Specification for Structural Joints using ASTM A325 or A4S0 Bolts. The nuts for these structural bolts shall be ASTM A563. One flat hardened washer meeting ASTM F436 shall be supplied with all bolts. All bolts, nuts and washers shall be galvanized and shall be furnished in an amount of 5% more than the number required for each size and length. Non-structural bolts shall be ASTM A307,1/4' diameter carriage bolts, zinc plated or galvanized. Self -drilling fasteners shall be #14 x t"Zinc Plated Hex Washer Head Tek Screws Power Actuated fasteners shall be Hilti sheet metal nail X -ENP -19 fastener. 9.5 Traffic Rail Rail to be galvanized steel Thrie-Beam Rail, 10 -gage thickness, with flared ends at each end of bridge. A 2 -sided crystal reflector tab shall be provided to be placed 6'-3" on center.