Based on the traditional calculation method of shear stress of box girder with variable cross section,the concept of prestress diffusion was put forward by considering the additional shear stress caused by the change of axial force.By introducing the prestress diffusion function and solving it by u-sing the wedge elastic body theory,the calculation method of shear stress of variable cross-section box girder based on prestress diffusion was established.Taking the mid-span cantilever casting section of a super-large bridge as an example,the comparison between the traditional calculation method and the calculation method in this paper shows that the change of axial force has great influence on the shear stress near the root,but little influence near the free end of the cantilever.In the construction stage,the traditional calculation method will greatly underestimate the shear stress and principal tensile stress in the section,so the influence of axial force change on shear stress cannot be ignored.
关键词
剪应力/预应力扩散/变截面梁/轴力变化
Key words
shear stress/prestress diffusion/beam with variable section/change of axial force
维普
万方数据