DESIGN AND STRESS ANALYSIS OF A NEW TYPE PRESTRESSED CONCRETE COMPOSITE BEAM

A new type of prestressed concrete composite beam( double prestressed composite beam)was introduced, its design feature was analyzed. The new type prestressed concrete composite beam was proposed to be applied to high-speed railway ballastless track bridge. Whose stresses in different construction stages were analyzed according to the design of an actual project and contrasted to conventional prestressed concrete beam. The results show double prestressed composite beam has a smaller stress gradient which is propitious to decrease the creep camber of prestressed concrete beam; about 10% of the tendon can be saved by the double prestressed composite beam, which has obvious economic advantages.