High-Performance Steel Bridge Design and Cost Comparisons

High-performance steel (HPS) is a relatively new and promising material for steel girder bridges. Several studies have been conducted regarding HPS, its properties, and its potential future use. The many benefits of HPS include its increased strength, the lighter structures that can be built with HPS, the possibly lower cost of bridges built with HPS, the ease of fabrication of bridges with HPS because of better weldability, and the significantly greater ductility and toughness of HPS compared with those of conventional steels of similar strength. Several bridges that have been completed with HPS are now in service and have met or exceeded expectations. Six alternative designs and cost comparisons for a two-span steel girder bridge are presented. The design alternatives include three homogeneous designs with HPS 485W (HPS 70W) girders, two conventional designs with 345W (50W) girders, and a design with a hybrid 345W/HPS 485W (50W/HPS 70W) girder. The results show that although the homogeneous HPS girder designs reduce the steel weight significantly, the additional cost of the HPS material tends to outweigh the benefits of the reduced steel weight. However, the hybrid design demonstrates considerable and definite savings in terms of both steel weight and total costs.