THE NEBRASKA HIGH PERFORMANCE STEEL TWO-BOX GIRDER SYSTEM

The Nebraska High Performance Steel (HPS) Two Box Girder project has been developed as a prototype structure for the replacement or new construction of typical grade separation bridges. These bridges represent a large market potential. The objectives for this prototype design are to simplify and accelerate construction, reduce cost, and increase life expectancy. This paper describes the prototype bridge design currently underway for a new two-span grade separation bridge near Omaha, Nebraska. The superstructure consists of twin box girders erected span-by-span without field splices. The design utilizes ASTM A709 HPS Grade 70W material. The deck is a full depth composite slab, precast, and posttensioned, designed for zero tension, with a wearing surface. Time dependent effects are fully accounted for. This paper describes the bridge analysis, design, and various constructibility issues. It is expected that the bridge will be constructed in 2002. Testing of various components will occur during design, and monitoring of the bridge performance will be provided in-service.