Studu On Longitudinal Force Of Cwe On Long-span Concrete Cable-stayed Bridge

With the development of bridge technology and the in-depth study of CWR on the bridge,cable-stayed bridges are increasingly used in the railway,especially when crossing wide canyons,rivers and straits.The shape and axis of the structure and components of the cable-stayed bridge have great changes before and after the load is applied.At the same time,the cable-stayed bridge is a high-order statically indeterminate structure,which is a "tower cable beam" spatial structure combination system.The interaction mechanism of beam rail on the cable-stayed bridge is complex,and the excessive interaction of beam rail will cause rail fracture or even endanger the driving safety on the bridge.Therefore,it is necessary to fully consider the characteristics of the cable-stayed bridge structure system and study the longitudinal stress and deformation law of the CWR on the long-span cable-stayed bridge.Based on the comprehensive analysis of the current situation of research,according to the characteristics of long-span cable-stayed bridge and track structure,this paper establishes a more complete spatial coupling model which can reflect the characteristics of cable-stayed bridge and the interaction between beam and track,and comprehensively analyzes the longitudinal force distribution and its influencing factors of the CWR on the long-span cable-stayed bridge.The main research contents are as follows:1.Taking the prestressed concrete cable-stayed bridge of a long-span cable-stayed bridge as an example,considering the interaction among rails,ballastless track(or track bed),beams,main towers,stay cables and piers,the spatial coupling model of ballasted track and ballastless track CWR on the four long-span cable-stayed bridge is established.2.Based on the spatial coupling model,taking the expansion force,deflection force,braking force and rail breaking force as examples,the paper analyzes the single-layer spring resistance model,double-layer spring resistance model and the longitudinal force distribution rule of the CWR on the cable-stayed bridge under the condition of ballastless track.According to the longitudinal stress and deformation characteristics of track and bridge structure,the stress and deformation characteristics of two kinds of track structure laid on cable-stayed bridge are compared.3.Considering the main tower temperature,different temperature difference load,small resistance fastener laying scheme and other factors,this paper analyzes the influencing factors of the longitudinal force of the jointless track on the long-span cable-stayed bridge,and from the point of view of reducing the longitudinal force and displacement of the structure,puts forward reasonable suggestions for the small resistance fastener laying.4.Based on the proposed longitudinal force calculation model of CWR on ballastless track and ballasted track cable-stayed bridge,taking the rail strength,CWR stability and rail fracture value as the calculation index,the safety of CWR on long-span cable-stayed bridge is checked,which provides theoretical guidance for the long-term service safety of long-span cable-stayed bridge track structure.