基于膨胀混凝土约束作用下悬索桥索塔力学性能研究

Mechanical Properties' Study on Expansive Concrete Filled Steel Tube Pylon of Suspension Bridge

为了研究大型悬索桥索塔在使用膨胀混凝土时的力学性能,本文以甘肃某大型单跨简支钢桁加劲梁悬索桥为研究对象,就钢管膨胀混凝土下的索塔各构件及整体力学性能进行了分析。结果表明:索塔格栅处应力集中区出现在顶面的加载区域;横梁最大剪应力出现在与左塔接触的顶部及右塔接触的底部区域;索塔塔柱钢管最大竖向应力出现在靠近横梁上下端及第二层塔基上部区域。同时得出,相较于上部荷载作用,膨胀混凝土的约束作用对钢管轴向应力作用更大。

In order to study the mechanical properties of large suspension bridge’s pylon with expansive concrete,one large single span simply supported steel truss stiffening girder of suspension bridge in Gansu province was studied in this paper,and the component and whole mechanical behavior of the pylon with expansive concrete filled steel tube were analyzed.The results showed that the stress concentration regions of pylon grid appeared at the top of the load area,the beam’s maximum shear stress appeared at the top of left pylon and the bottom of right pylon which contacted with beam,the maximum vertical stress appeared at the pylon steel columns’top and bottom which contacted with beam,and it also appeared at the top of the tower foundation’s second layer.We also drew the conclusion that the expansive action played a major role to steel pipe’s axial stress compared with the upper load.