Abstract: To analyse the mechanical properties of cast-in-place prestressed concrete curvilinear box girder under load,this paper took the actual project as the background,with the establishment of finite element model of curvilinear box girders,analyzed the mechanical characteristics and deformation law of the structure under different loads,and summarized the corresponding characteristics.Through the finite element analysis of the cast-in-place prestressed concrete curved box girder,the results show that there is a big difference between the arc lengths of the inner and outer sides of curved box girder,and the stress of the inner and outer sides of the same section of box girder is different;the stress produced when the same load is applied to the outer side is greater than that produced when it is applied to the inner side;under the vertical normal load of curved box girder,the longitudinal stress of mid-span section is less than that of side-span section;the vertical bending of the bridge is accompanied by the transverse torque,but the vertical bending value is far greater than the transverse torque value.

Key words: prestressed concrete, curved box girder, finite element model, stress deformation