Abstract:The long-span flat-arch structure is used in the footbridge project of Juxing Bridge. There are great difficulties in its construction on the soft soil subgrade. In order to solve the problem of horizontal thrust of the flat-arch structure, the variable force state of V-pier structure is designed from hinged rotation, to tension release of arch pressure, and then to rigid joint non-rotation. Through the rigorous calculations and analysis, the arch system is partially converted into a beam system, which realizes the remarkable reduction of horizontal thrust. In the monitoring of the construction process of the actual structure, the collected data give a good support for the theoretical analysis. The method of "rear axle rod to control horizontal thrust" explores a new possibility for the realization of large-span flat-arch structures built on the soft soil subgrade.
