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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Engineering Services for GOll,ernment Infrastructure RFQ No. 07-03.0,1 2.3 Preliminary and Final Bridge Design .. ~ ~ The design of the proposed North Bay Road Pedestrian/Bike and Emergency Vehicle bridge will be in accordance with the current AASHTO Pedestrian and AASHTO LRFO design specifications, FDOT LRFD Structures Design Guidelines and in full compliance with the requirements of the RFP. Curved Steel superstructure will be designed using the latest FDOT Criteria for the Design of Horizontally Curved Steel Structures; for a bridge with curved steel members for part or all of its length, design the entire bridge, including substructure (with the exception of the traffic railings) in accordance with the 2003 AASHTO Guide Specifications for Horizontally Curved Steel Girder Highway Bridges and the AASHTO Standard Specifications for Highway Bridges, 17th Edition with a HS-25 live load. Also, the latest edition of the FOOT Structures Design Guidelines and Detailing Manual will be used. Where applicable, fracture critical member design considerations, details and fabrication will be in accordance with the latest AASHTO Guide Specifications for Fracture Critical Non- Redundant Steel Bridge Members and applicable Interims. Also, any temporary enhancements for the pedestrians like a canopy, etc. will be designed in accordance with the latest Florida Building Code (FBC) and supplements. Load rating of the bridge will be performed in accordance with the Manual for Condition Evaluation and Load and Resistance Factor Rating (LRFR) of Highway Bridges and latest FDOT Criteria. Our involvement with load rating bridges has a long history in Florida and Marlin Team members have performed load-ratings for numerous bridge structures BHA will use our in-house software and BSDI software for the design of curved steel girders; the BSDI software is a 3 dimensional, finite element program that accounts for all major stresses including torsion and warping. We have experience with this program having used it for the final deign and load rating of the S.R. 869 Sawgrass Expressway/Panther Arena Interchange, 1-95/1-595 Interchange in Broward county and most recent in S.R. 826 (Palmetto Expressway)-Section 2 for FOOT District 6 in Miami-Dade County. BHA will also use the latest technology in plans production; our in-house software "Geopak Rebar" is capable of detailing reinforcement bars, producing a bar schedule (length and bending), and calculating reinforcing steel quantities as well as automatically monitoring bar marks and shapes. Geopak Rebar will be used for the superstructure deck and substructure plans to accelerate plans production and in areas of congested reinforcing steel as shown in the 3-D Model. 3-D MODEL 2.4 Proposed Alignment The proposed North Bay Road Pedestrian/Bike and Emergency Vehicle bridge will connect the southern end of North Bay Road, just south of 174th Street, to the south bank of the canal, with a pedestrian section continuing south to 172nd Street. The ultimate design will be for a two- lane, two way facility with sidewalks for the entire project length. At this time the usage of the facility will be for pedestrians, bicycles and emergency vehicles; regular vehicular traffic is precluded due to a total available width of only 20' at the south end of the project where right of way is restricted to a 20' easement. Horizontal Alignment: Our proposed horizontal alignment consists of tangent sections at the north and south ends, connected with a set of reverse horizontal curves. We envision developing the horizontal curves with 175' radius which is consistent with a design speed of 25 MPH per FDOT. We propose a typical roadway/bridge section that consists of two 15' travel lanes with a crown in the center, then 2.5' shoulder on each side, next 1.5' concrete barrier wall each side, then 8' wide sidewalk ~~~~,