2019-02-11-minutes-public-works-study-session

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5.5 Seismic Design Bridge shall be designed to transfer seismic lateral loads per AASHTO Bridge Design Specifications. 6.0 MATERIALS OF CONSTRUCTION 6.1 Structural Steel Bridge shall be weathering steel and all structural steel shall be ASTM A588. 6.2 Deck Material Decking to be 4 -Z6 -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 trough to top of the profile. Width of the plank shall be 12-13116" with one 13116" 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). 6.3 Wearing Surface Gravel Top of side dam shall be 3.5" above top of 4.25 -inch Steel Bridge Deck for gravel wearing surface. Gravel wearing surface to be provided by others. 6.4 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 orA490 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% in excess of 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 1" Zinc Plated Hex Washer Head Tek Screws. Power Actuated fasteners shall be Hilti sheet metal nail X -ENP -19 fastener. 6.5 Traffic Rail Rail to be galvanized steel Thrie Beam Rail, 10 -gage thickness, with flared ends at each end of bridge. Roadway approach guardrail to be provided by others. A 2 -sided crystal reflector tab shall be provided to be placed 6'-3" on center. 6.6 Expansion Joint Expansion joint steel galvanized angle shall be a minimum of 318" thick and shall be shop welded to girders. Damaged galvanizing and 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).