Practical Calculation of the Lateral Destabilization of Double Rib Cable-stayed Arch Bridge

The cable-stayed arch bridge is a new form of bridge structure,which combines characteristis of the cable-stayed bridge and the arch bridge.The stability of arch is different from the normal arch bridge because the cable shares the load with the arch rib.On the basis of the energy principle,the text deduces a practical method for calculation of the lateral destabilization critical loading of the double rib cable-stayed arch under the premise of considering the factors of the stiffness of bridge floor and non-oriented conservative loadings of hanger and cable.The precision of the method is verified via an example.Analysis on the influence of parameters of the cable-stayed arch bridge on its lateral destabilization critical loading is made with the practical method.The parameters include the pretension stress,the inclination of cable,the scope of cables arranged on the arch and the distance between bridge tower and arch.