Abstract:The prestress introduction characteristics of new type steel-concrete composite beam with corrugated web and internal prestress was investigated in this work. A new type of steel encased concrete member was developed to introduce the prestress into the lower flange of the steel-concrete composite beam, and due to the corrugated web, the prestress could be introduced to the lower and upper flange more efficiently. Compared with the conventional composite beam with corrugated web, the mechanical behavior of the new structure can be greatly improved and the weight of beam can be remarkably reduced, so that the frequent replacement of extra-tendons can be avoided. Based on the theorem of Castigliano and thecoordination characteristics of cross-sectional stiffness of composite beam with corrugated steel webs, the method of calculating the efficiency of prestress introduction into composite beam with corrugated web was derived in this work. By comparing the theoretical calculation results with the finite element results, the coefficients of prestress introduction efficiency of composite beam with corrugated web had the consistent variations, validating the rationality of the calculation method proposed in this study.