【摘要】 建立了薄壁箱型梁桥在任意荷载作用下考虑剪力滞剪切变形影响的振动分析理论体系,为分析薄壁箱型桥梁等结构振动时的剪力滞剪切变形效应提供了计算手段。采用变分原理,推导了考虑剪力滞剪切变形效应的薄壁箱梁振动控制微分方程、边界及初始条件,探讨了方程的解法,建立了方程解的差分格式,并论证了差分格式的稳定性、收敛性,最后提供了简支梁算例,计算结果验证了方法体系的可行性。同时表明:在薄壁箱梁振动时,剪力滞效应和剪切变形使跨中位移明显增大,应力集中现象明显,且剪力滞的影响比剪切变形的影响要大。更多还原

【Abstract】 The article attempts to build vibration analysis system of thin-wall box-girder bridges subjected to any dynamic load including shear lag and shear deformation,and provide mathematic means to vibration analysis of thin-wall box-girder bridges considering shear lag and shear deformation.By usingcalculus of variation,for the first time vibration controlling differential equation,boundary and initial conditions of thin-wall box-girder is deduced including shear lag and shear deformation,and after equation solution is discussed,difference scheme of the equation is set up,then,stability and convergence property of difference scheme is demonstrated.Lastly,mathematic example of simply supported beam is provided,which confirm the feasibility of means system.In addition,the calculating results shows that shear lag and shear deformation make displacement response of thin-wall box-girder distinctly larger and stress concentration more evcdent.The effect of shear lag is also larger than that of shear deformation.更多还原