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4.0 STRUCTURAL DESIGN LOADS <br />4.1 Dead Load <br />The bridge structure shall be designed for the total bridge weight plus an additional allowance of 80 pounds <br />per square foot total wearing surface. <br />4.2 Vehicle Load (VL) <br />Bridge shall be designed for one lane of traffic, supporting HL -93 vehicle plus Dynamic Load Allowance. <br />The design ADTT (Average Daily Truck Traffic) shall be 100. <br />4.3 Wind Load (WS) <br />Bridge shall be designed for a 50 pounds per square foot wind load applied horizontally against the height of <br />the stringer plus the side dam. <br />4.4 Fatigue Load (FL) <br />The fatigue loading shall be as specified in AASHTO LRFD Bridge Design Specifications, current edition. <br />4.5 Railing Loads (RL) <br />Traffic rail shall be designed in accordance with AASHTO LRFD Bridge Design Specifications, current edition, <br />Appendix A13.2. Traffic rail has not been physically crash -tested. <br />Traffic rail shall meet the force requirements for a TL -2 rating.Traffic rail shall meet the force requirements for a <br />TL -2 rating.Traffic rail shall meet the force requirements for a TL -2 rating.Traffic rail shall meet the force <br />requirements for a TL -2 rating.Traffic rail shall meet the force requirements for a TL -2 rating. <br />4.6 Other Loads <br />The bridge shall be designed to accommodate a temperature range of -30 degrees to 120 degrees <br />Fahrenheit. <br />4.7 Combination of Loads <br />The load combinations and load factors to be used shall be as per specified in AASHTO LRFD Table 3.4.1-1. <br />5.0 STRUCTURAL DESIGN CRITERIA <br />5.1 Deflections <br />Per AASHTO LRFD Bridge Design Specifications, vehicle load deflection limits are not required. However the <br />Bridge Manufacturer will typically try to provide an anticipated vehicle load deflection of approximately <br />L1500, expressed as the ratio of span length to deflection. <br />5.2 Fracture <br />The main beams shall meet CVN values of 20 ft -lbs (minimum) @ 40 -degrees Fahrenheit. <br />5.3 Wheel Load Distribution <br />4.25 -inch Bridge deck shall be designed to support the maximum wheel load from the design vehicle. <br />5.4 Girder System <br />Bridge superstructure system shall have a minimum of three girder lines. <br />