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10.0 FINISH <br />10.1 Blast Cleaning <br />Exposed surfaces of structural steel to be wipe cleaned in accordance with the Steel <br />Structures Painting Council (SSPC), Surface Preparation Specification No. 1, latest <br />edition, (SSPC-SP1), Wipe -Off Clean. Exposed surfaces of steel shall be defined as <br />those surfaces seen from the deck or from the outside and bottom of the structure. <br />11.0 BEARINGS <br />11.1 Bearing Plates <br />The Manufacturer shall supply two sets. Bearing plates shall be used under the stringers <br />at both ends of the bridge and shall be designed to support the anticipated reactions and <br />thermal movement. Bearing plate material shall be ASTM A572 Grade 50 or A588 for <br />painted, metallized and galvanized bridges or ASTM A588 for weathering steel bridges. <br />The Bridge Manufacturer should design the bearing plates such that one end of the <br />bridge is fixed and the other end allows for expansion. All bearing plates should have a <br />minimum of two holes to receive anchor rods (one on each side of the stringer). For the <br />expansion base plates, holes shall be slotted with a minimum of 3" in the slot to allow for <br />expansion and contraction. All bearing plates shall be shipped loose for field Installation <br />by others; field welded to the stringers by an AWS D1.5 certified welder. <br />If the longitudinal grade of the bridge Is equal to or greater than 1.50/c, then the bearing <br />plates shall be beveled across their width to provide a level bearing condition on the <br />elastomeric pads. <br />11.2 Elastomeric Pads <br />The Manufacturer shall supply adequate pads to support deployment of two separate <br />structures (30'160'). The Bearing plates will be placed on top of elastomeric pads. <br />Elastomedc pads shall be 60-Durometer Neoprene and are to be used only as leveling <br />pads and do not most AASHTO LRFD design criteria. <br />12.0 PRECAST CONCRETE SILLS & ANCHOR PLATES <br />Precast concrete sills shall be designed and supplied by the Bridge Manufacturer. The <br />precast concrete sills she be cast by a plant which carries the National Precast Concrete <br />Association (NPCA) certification. The precast concrete sill(s) shall be 1'-6" deep by 2'-6" <br />wide by 1 S' long. The precast concrete sill shall be reinforced with stirrups and <br />longitudinal reinforcing bars (minimum Grade 40), and have a minimum concrete strength <br />of 4000psi. A 2" minimum concrete cover shall be maintained for all reinforcing. Lifting <br />lugs shall be installed to aid in the unloading and placement of the precast concrete sills. <br />On top of the precast concrete sill, an ASTM A588 plate (112" thick by 6" wide and <br />running the entire length of the sill) shall be embedded into the concrete with shear studs. <br />This top plate will be used to attach the anchor plates via field welding by Kittitas County. <br />Comer embed angles shall be installed in the sills to allow for the field welding together of <br />the multiple sections prior to the installation of the full bridge superstructure. Anchor <br />plates will consist of two 1.25" diameter by 5" long fully -threaded zinc plated rods welded <br />to the surface and spaced to match the hole spacing in the bridge bearing plates and <br />slastomeric pads. Two nuts and one washer (all galvanized) shall be supplied with each <br />rod. <br />