Study On Longitudinal Force Of CWR On Special Structure Bridge

In recent years,due to the needs of China’s railway development,some special structure bridges began to appear in the construction of railway bridges,which benefited from the advantages of large span capacity,aesthetics and economy.Various special bridge types such as cable-stayed bridge and arch bridge have attracted the attention of railway builders because of their unique spanning capacity.Arch bridge is especially suitable for Long-span Railway Engineering because of its large span force and greater rigidity;Compared with other bridges,cable-stayed bridges have more changes and wide span.Thanks to the structural advantages of cable-stayed bridges,they can meet the requirements of economy and structural strength in the construction of many railway bridges,and their main span selection range is wider.Therefore,for the special structure bridge,the longitudinal stress and deformation law of CWR on the bridge must be studied on the basis of considering its structural characteristics.Based on the existing research and the characteristics of railway special structure bridge and track structure,this paper establishes the finite element spatial coupling model of railway cable-stayed bridge and arch bridge considering the main components such as track,bridge,pier and abutment,stay cable,arch rib and suspender by using the finite element software ANSYS,and studies the longitudinal force distribution law and structural influence of CWR on long-span double tower cable-stayed bridge and steel truss triple continuous arch bridge.The main research work is as follows:(1)Taking the main bridge(160 + 320 + 160)m of a long-span cable-stayed bridge as the research object and fully considering the structural characteristics of the cable-stayed bridge,a finite element model based on the integration of line bridge pier and considering the structures such as stay cable and main tower pier is established;Taking the(120 + 120 + 120)m continuous steel truss arch bridge of Xianyang Weihe River Bridge on Longhai Railway as the research object and fully considering the structural characteristics of the arch bridge,a finite element model based on the integration of line bridge pier and considering arch rib,column pier and abutment is established.(2)According to the basic principle of beam rail,the spatial coupling model of cable-stayed bridge including track,beam body,stay cable and column pier is established with the finite element software ANSYS.Considering the working conditions of temperature load,train load and braking load,the longitudinal additional force of CWR on the bridge is calculated and the law of stress and deformation is obtained.In addition,considering the influence of the unique cable structure on the longitudinal force of the cable-stayed bridge,the influence of the cable-stayed bridge structure on the longitudinal force of CWR is explored under different working conditions of cable stiffness and temperature difference.According to the characteristics of track structure,the stress of rail with small resistance fastener and constant resistance fastener on special structure bridge is analyzed.(3)According to the basic principle of beam rail,the spatial coupling model of arch bridge including track,beam body,arch rib,suspender and column pier is established with the finite element software ANSYS.Considering the working conditions of temperature load,train load and braking load,the longitudinal additional force of CWR on the bridge is calculated and the law of stress and deformation is obtained.Considering the influence of the unique arch rib,suspender and other structures on the longitudinal force of the arch bridge,the influence of the arch structure on the longitudinal force of CWR is explored under different working conditions such as arch rib stiffness and temperature difference.According to the characteristics of track structure,the stress and deformation characteristics of rail are analyzed for the small resistance fasteners and constant resistance fasteners laid on the arch bridge.(4)Based on the established longitudinal force calculation model of CWR on cable-stayed bridge and arch bridge,referring to the existing specifications,and taking the strength and stability of rail and the stability capacity of CWR as the check calculation index,the safety check calculation of CWR on special structure bridge is provided.The research results of CWR on special structure bridges provide reference and reference for the design of such bridges in the future,and improve the research of CWR on bridges in our country.