超大跨径变截面钢筋混凝土拱式渡槽抗震分析

Aseismic Analysis of Long Span Reinforced Concrete Arched Flume with Variable Cross Section

结合跨径200m的超大跨径变截面拱式渡槽的结构设计方案,通过建立有限元模型,对渡槽进行了动力特性和地震响应分析。结果表明,设计方案拱轴系数的取值合理,拱脚偏心弯矩引起的拉应力在允许范围内;变截面的做法增大了拱脚截面刚度,增强了拱圈的稳定性,有效地减小了起控制作用的拱脚处的轴向拉应力,可满足渡槽抗震要求。

Combining the structural design scheme of 200 m span arched flume with variable cross section, FEM is established to analyze dynamic characteristic and seismic response. The results show that the value of arch axis coefficient is reasonable for the current design scheme; the tensile stress caused by eccentric bending moment of springing is in the al- lowable range; the variable cross section increases the stiffness of springing section and enhances the stability of arch ring, which reduces the axial tensile stress of springing effectively. Therefore, it can meet the aseismic requirements of flume.