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

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SPECIAL PROVISIONS FOR 4.25 -INCH STEEL BRIDGE DECKED MODULAR BEAM BRIDGE(S) 1.0 GENERAL 1.1 Scope These specifications are for fully engineered multi -piece modular bridge(s) of steel construction with 4.25 - Inch Steel Bridge Deck and shall be regarded as minimum standards for design and construction. The work included under this item shall consist of design, fabricating, finishing and delivering the steel modular beam bridge superstructure including bearings, attachment hardware, and safety rail and expansion joint plate. 1.2 Qualified of Bridge Manufacturer The Bridge Manufacturer shall utilize an engineer who is experienced in bridge design to perform all engineering related task and design. The engineer shall have a minimum of 10- years'experience in bridge design and be a currently licensed civil or structural engineer in the State of Washington. Qualified Bridge Manufacturers must have at least 5 -years' experience fabricating these types of structures and shall have an up to date certification by AISC as a Certified Bridge Fabrication Intermediate (Major) with Fracture Critical Endorsement. All suppliers shall fabricate their product, no brokers are allowed. Bridge Manufacturers shall provide Kittitas County documentation affirming the aforementioned qualifications prior to contract award. These documents will be evaluated by Kittitas County for accuracy and ability to provide a bridge(s) in accordance with these specifications prior to contract award. 1.3 Bridge Manufacturer's Design Professional and Submittals The Bridge Manufacturer shall have as a direct employee, an engineer who is experienced in bridge design to perform all engineering related task and design. The engineer shall have a minimum of 10 years experience in bridge design and be a currently licensed civil or structural engineer in the State of Washington. Engineering drawings, 11x17 format, shall be prepared and submitted to Kittitas County for review after receipt of the order. Submittal drawings shall be unique drawings, prepared to illustrate the specific portion of the bridge being fabricated. All relative design information such as member size, ASTMIAASHTO material specification, dimension necessary to fabricate and required welding shall be clearly shown on the drawings. Drawings shall have cross referenced details and sheet numbers. All drawings shall be stamped, signed and dated by the Bridge Manufacturer's Design Professional. Structural calculations for the design of the bridge superstructure shall be prepared and submitted to Kittitas County for their review after receipt of the order. Calculations shall include complete design, analysis and code checks for the controlling member, connectivity and support conditions, deck design, deflection checks, bearings and all splices. A signed and stamped load rating shall be submitted to Kittitas County prior to delivery of the bridge. The load rating shall be performed per WSDOT Bridge Design Manual and AASHTO Manual for Bridge Evaluation LRFR method requirements. The load rating shall include rating factors for the HL -93 design truck, AASHTO legal trucks, NRL, WSDOT OL -1 and OL -2 and EV -2 and EV -3 trucks.