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

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6.0 BRIDGE GEOMETRY 6.1 Span Length The bridge span length shall be 90'-0" (straight line dimension) and measured from end to end of the bridge structure. Bridge shall have an all -bolted splice (both flanges and web) located at the 30'160' location. No field welding splices will be allowed. Further, additional base plates are to be added at the splice location such that each section (30'/ 60') can be used independently as separate spans. Post blocks and posts shall be spaced such that each span can be used independently. Railing and wood running planks need to be spliced at this location. Further, additional leveling pads and railing flared ends need to be supplied so each span can be utilized independently. 6.2 Width The bridge width shall be 14'-0" and shall be as measured from the inside face to inside face of rail. 6.3 Lower Steel Clearance The bridge manufacturer shall determine the distance from the top of the deck (measured from the highest point of the deck) to the bottom of any steel member. 6.4 Rail Height Top of rail shall be 2'-7" above the top of the wearing surface for vehicular traffic only. The finished product shall have all necessary connections and be manufactured in a manner that the bridge and its rail sections can be deployed as one 90 foot unit or separately as one 30 foot unit and one 60 foot unit. 6.5 Camber A single simple -span bridge shall have a vertical camber dimension at the mid -span equal to 100% of the anticipated full dead load deflection. If beam mill camber is adequate to accommodate full dead load deflection, then indicate so on drawings. Note, the beams shall be cambered to offset full dead load deflection for the full 90'-0" span. That means that there will be permanent up camber in the 30' and 60' spans. 6.6 Elevation Difference The top of the decks shall be at the same elevation at each end of the bridge. 7.0 STRUCTURAL DESIGN LOADS 7.1 Dead Load The bridge structure shall be designed for the total bridge weight plus an additional allowance of 80 pounds per square foot total wearing surface.