25.1.1. Minimum 16'- 0" clear/useable travel width between face of steel rails. 25.1.2. 40' overall/nominal bridge length. 25.1.3. Bridge shall be designedperthe AASHTO 2012 LRFDBridgeDesign Specificationsforthe following load criteria: 25.1.3.1. HL93 loading. 25.1.3.2. Six-axle/150-kip combination vehicle consisting of a 1Ok steer axle, two drive axles with 28k each, and three trailer axles with 28k each. Axle spacing shall be as follows: 0 - 14.25' - 4' - 35' - 5' - 5'. 25.1.3.3. Stringersshall be designed with no speed restriction [full impact loading]. 25.1.3.4. Design shall incorporate the dead load of a potential/future 3" asphaltoverlay. 25.1.4. P.E. stamped design letter of certification, drawings, and stringer/deck calculations shall be provided. Design shall be stamped by a PE licensedeitherin the state of bridge manufacture or the state of delivery. 25.1.4.1. The firm that seals the plans/calculations shall have an insurance policy in effect providing professional liability coverage for errors and omissions. 25.1.5. Allsteelshall be new, of domestic origin, and of minimum strength asindicatedin stringer calculations. 25.1.6. Welding procedures and personnel shall be qualified per AWS D1.5. 25.1.7. Full-dimension steel end plates [back-walls] of minimum 3/8" thick steel, provided at both ends to eliminate the need for a back wall on the abutments. 25.1.8. The guardrail system shall meet AASHTO requirements for pedestrian guardrails, except that railing height shall be increased to54". 25.1.8.1. Railing system shall consist of longitudinal steel rails. 25.1.8.2. The lowermost rail shall be capped with a treated timber rub-rail, with the interior face of the timber to be inside of the edge of the timberdeck. 25.1.9. Finish shall consist of two coats of epoxy primer with a urethane topcoat applied per the paint manufacturer's recommendations. Color will be Architectural Brown. 25.1.10. A 56-mil waterproofing membrane on 4-mil carrier film, slit to overhang the top flanges of the stringers by ¼" - ½" on either side, shall be pre-installed on the top flanges of all stringers.
