Research On Mechanical Properties Of Prestressed Steel & Concrete Composite Beam

Recently, simply supported prestressed steel-concrete composite beams have been widely used in freeway and urban bridge construction, dueing to the steel's tensile strength and the concrete's compressive strength are been fully exerted, having the advantage of legerity and artistic of framework, bigger span , convenience and faster in construction, and little influence on traffic. However, domestic and international theoretical researches are not enough on aspect of prestressed steel-concrete composite structure and there are not respective provisions in the Chinese design specifications till now, so these aspects have a great influence on the application of this reasonable structure system.Based on comprehensive collection of the existing research documents home and abroad, this paper expounds the working principle of prestressed steel-concrete composite beams during construction and operation, discusses the influencing factors of mechanical properties of prestressed steel-concrete composite beams, describes several design methods of prestressed steel-concrete composite beams in detail, summarizes the practical calculating formula of prestressed steel-concrete composite beams in various functional states, this paper can provide a significative reference for the design and construction of the same kind of bridge.For the sake of analyzing the mechanical properties of prestressed steel-concrete composite beams, the paper combines the load test research of Xingguang linking route overpass in Inner Mongolia, testing the data of stress and deformation under design loads; uses 3D Finite Element Method (FEM) to carry through numerical simulation to load test, the results of the theoretical analysis are agreed well with the experimental data.Through the load test and finite element numerical simulation analysis, the paper provides bases for more studies of prestressed steel-concrete composite beams, provides theoretic basis and technical guide for overall extension and application of prestressed steel-concrete composite beams, and this dissertation has the certain theoretical meaning and practical value.