Interaction Between Long-Span Curved Continuous Bridge And Track

Abstract:Long-span curved continuous girder bridges could adopted to topography, water conservancy and transportation conditions. It became widely used in high speed railways. Interaction between tracks and bridges was one of the important control factors to the safety and design of curved long-span continuous girder bridges and long welded rails. This thesis focused on long-span curved continuous girder bridges, the interaction between tracks and bridges were researched systematically. The main content included: Researches conducted on the interaction between simply supported beams of high speed railway and CRTS Ⅱ slab ballastless track in this dissertation. The main contents included:(1) A2lines high speed (48+7x80+48)m bridge was cited as the example and studied. A rail-fastener-sleeper-ballast-grid-pier integrated spatial finite element model(FEM) was established. The longitudinal resistance, transverse resistance and vertical stiffness of the lines were simulated. It reflected the relations between tracks, sleepers, bridge deck and piers more accurately.(2) The stress characteristics and deformation laws of ballast tracks under braking loads, temperature and vertical train load were researched; values and distribution principles of expansion and contraction additional forces, bending additional forces and braking additional forces of long-span curved continuous girder bridges were explored.(3) FEM results showed the combination layout of small resistance fasteners and expansion joints was required, it could decrease the stress in rails to a great extent. Besides, the improvement methods of longitudinal stiffness, constraint conditions between piers and girders and braking pier’s locations were discussed. The conception of braking span was proposed that change the constraint conditions between piers and girders could reduce rail stress.