悬索桥重力刚度法及主缆水平拉力计算

对于大跨度悬索桥,加劲梁的抗弯刚度远远小于具备强大拉力储备的主缆的重力刚度,加劲梁的抗弯刚度的大小对全桥结构行为的影响只是处于次要地位。忽略加劲梁的抗弯刚度而将悬索桥当成一个单纯的索结构来分析它的内力和变形的方法就是重力刚度法。通过与悬索同跨简支梁的剪力和弯矩来明确重力刚度的概念,并揭示该剪力和主缆水平拉力、该弯矩和主缆挠度之间的关系。分别采用重力刚度法和通用软件ANSYS来计算悬索桥的内力和变形,其结果接近,说明采用重力刚度法计算的结果也是具有参考价值的。

The Gravity Stiffness Method of Suspension Bridge and Calculation of Horizontal Axial Force of Cable

For the long-span suspension bridge,the vertical deflection resistance stiffness of stiffening girder is far less than the gravity stiffness of suspension cable in the whole suspension bridge structure.If the stiffness of stiffening girder is ignored and the suspension bridge is considered as a pure cable structure,the way we calculate the internal force and the deformation is known as gravity stiffness method.The paper will clarify the concept of gravity stiffness by the shear force and the bending moment of the simple-supported beam that has the same span as the suspension cable,and note the relation of the shear force and horizontal axial force of cable as well as the bending moment and the deformation of cable.What is more,the author will check the results of gravity stiffness method by ANSYS in order to clear that the results of gravity stiffness method are meaningful.