大跨悬索桥塔顶位移控制值分析

Analysis of Tower Top Displacement Control Values of Long-Span Suspension Bridge

为了分析某悬索桥上部结构施工过程中塔顶纵向抗推刚度和允许位移,采用通用有限元程序ANSYS建立了3种不同单元形式的桥塔有限元空间模型,利用这3种模型分别计算了桥塔的抗推刚度和抗扭刚度,得到了比较一致的结果。提出用2种混凝土应力水平来控制塔顶允许位移,分别采用线性和非线性方法,计算了某悬索桥塔在2种荷载工况下,按不同应力水平条件控制下塔顶允许位移值和塔身的混凝土最大应力。

To analyze the tower top longitudinal anti-push rigidity and allowable displacement of a suspension bridge while its superstructure was being constructed, the finite element spatial models of 3 kinds of different elements for the bridge tower are established, using the general finite element program ANSYS. With these 3 models, the anti-push and anti-torsion rigidity of the tower are respectively calculated and fairly agreeable results are obtained. Two kinds of concrete stress levels are proposed for use of controlling the tower top allowable displacement. The allowable displacement values of the tower top and maximum concrete stress of tower shaft of a suspension bridge controlled with different stress levels under two kinds of loading cases are calculated, respectively using linear and non-linear methods.