薄壁渡槽结构的整体稳定性分析

Overall stability analysis of aqueduct structure

根据矩形薄壁渡槽整体扭转屈曲的变形特点,提出了矩形薄壁渡槽整体扭转屈曲的计算方法。考虑了屈曲前预应力和竖向变形的影响,采用伽辽金法推导了矩形薄壁渡槽的扭转屈曲临界荷载。对于矩形薄壁渡槽,在传统渡槽断面尺寸和跨径下,其侧向扭转屈曲临界应力大于混凝土抗压强度设计值cf,因此,在一般渡槽中不会发生侧向扭转屈曲。如果采用高屈服极限钢材,必须进行稳定性验算,所得结果和结论可为薄壁渡槽整体稳定性设计提供参考。

According to the characteristics of torsional buckling of rectangular thin-walled aqueduct, a method for calculating the torsional buckling of rectangular thin-walled aqueduct is proposed. Considering the influence of pre-buckling prestress and vertical deformation, the critical torsional buckling load of rectangular thin-walled aqueduct is derived by Galerkin method. For rectangular thin-walled aqueducts, the critical stress of lateral torsional buckling is larger than the design value of concrete compressive strength CF under the traditional section size and span, so lateral torsional buckling will not occur in general aqueducts. If high yield limit steel is used, stability checking must be carried out. The results and conclusions obtained can provide reference for the overall stability design of thin-walled aqueduct.