Economy of Corrosion-Resistant Steel in Highway Bridges

Cost studies indicate that corrosion-resistant high strength low alloy steels have definite economic possibilities for use in short and medium length highway bridges. A nickle-copper type of high strength low alloy steel should be used due to its better resistance to atmospheric corrosion. Analytical cost comparisons are made of the superstructures of typical short span concrete slab and rolled wide flange steel stringer highway bridges fabricated from nickel-copper high strength low alloy steel with those fabricated from ASTM A7 and A373 steels. Cost comparisons are made for welded I-section stringers with concrete deck for short and medium length highway bridges. These structures are designed in accordance with standard practice and specifications. Cost comparisons are made of the use of high strength steels in forms for highway bridges independent of standard design specifications. A precast high strength concrete deck is designed to act integrally with a one or a three cell steel box girder. A design procedure is presented for the composite box superstructure.