Abstract:When a viaduct is limited by a river, road, metro and underground pipeline, the overhanging crossbeam is an effective solution for use. Combined with the 4×28.9 m steel box beam bridge with overhanging crossbeam of the sixth left main line of Fenghuangshan Viaduct, the design, calculation and construction of the bridge are introduced, and the value of crossbeam height and the stability measures of crossbeam during construction are discussed, which can provide the reference for the design of the similar bridges at home and abroad.