Abstract:Aiming at the outstanding problem that the composite bridge is affected by the gradient temperature in the life cycle of the northwest alpine and large temperature difference area. Based on the new-model corrugated steel web (CSW) simply supported composite box girder on a highway in Gansu Province, an analytical calculation method of temperature effect of the composite box girder bridge was established by considering the effective stiffness of the composite bridge panel, the internal force balance of the micro-section of the sub-beam, the deformation coordination between the sub-beam and the shear deformation effect of the web.The reliability of the method was verified by fine finite element numerical simulation. The results showed that under the vertical temperature gradient, the bending moment, stress and interfacial shear of the composite box girder were hyperbolic cosine distribution along the beam axis, while the relative slip between layers was hyperbolic sine distribution. Whether the web shear deformation was considered or not had a great influence on the temperature response of the composite box girder, and the influence range along the beam axis was mainly related to the interlaminar slip stiffness. Ignoring the shear deformation effect of corrugated steel web could easily lead to the small calculation results of interlayer slip in the middle of the beam, but the problems of excessive interlayer shear force and relative slip value near the end of the beam should be paid more attention in the structural design. The influence of temperature difference between composite bridge slab and web interface and concrete line expansion coefficient on the temperature response of the structure cannot be ignored. In the design, the adverse effects of the above factors on the structure can be weakened or eliminated by optimizing the layout of shear connectors.