An Effective Method To Improve The Lower Arch Bridge

In recent years,Bridges tend to be multi-functional and heavy-duty.Many railway arch Bridges with dual-use,multi-lane and multi-fine railways have been built,and improving the bearing capacity of arch Bridges has become the key point in the design of large-span arch Bridges.In traditional concrete-filled flexible derrick arch bridge arch rib under the influence of live load and the characteristics of large deformation of main girder,especially for overloaded railway Bridges,limiting displacement deformation of the arch rib and girders to improve the overall structure stiffness and stability is must pay attention to the problem,and on this basis,this paper puts forward an improved concrete-filled flexible new bridge type derrick arch bridge to solve the above problems.The new bridge type is based on the traditional flexible hanger rod and six a-type supports are added.The main feature is that three a-type supports are added to the single arch rib,and the a-type supports are located at 1/4,1/2 and 3/4 of the arch rib respectively.The top of type A support is connected to the arch rib,and the two bottom ends are connected to the main beam,forming A triangular stable structure.This paper mainly introduces the structural form and mechanical principle of the new bridge.Through the finite element software Midas/civil,the structural strength,stiffness,stability,dynamic performance,temperature response and fatigue stress of the new arch bridge and the ordinary arch bridge were compared and analyzed,and the mechanical properties of the new arch bridge in different sagittal span ratio,type A bracing area and type A bracing Angle were studied.The research shows that,due to the addition of type A bracing,the force transfer path of its structure changes greatly,and the added 6 type A bracing have strong deformation resistance,effectively restricting the deformation of arch rib and main beam.A large number of examples show that the bridge has good mechanical properties and can be used to build Bridges with high requirements on stiffness and dynamic performance.