The Borger Plate Ballasted Track Bridge Transition Section Vertical Dynamic Response Analysis

With the rapid development of modern high-speed railway and passenger dedicated lines, ballastless track is being widely used, the form paved on the bridge is more universal. Since the engineering properties of embankments and bridges are so different that serious unevenness is prone to occur in the linking of embankments and bridges. Besides, this phenomenon is worsened with the increase of the train running speed and the axial load, quickens the distortion and destruction of the track, affects the comfort and stability, even endangers the safety of the train.Based on the research status of vehicle-track-bridge and the transitional section of the embankments and bridges at home and abroad, on the basis of comprehensive analysis, in this paper, the B(O|¨)gl slab ballastless track is used as the carrier. The track between every adjacency two fastener is treated as an element, in which the rail is simulated as continuity-point-suporting Euler beam, the cushion of the rail is simulated as line spring and dampers, the track slab is simulated as elastic plates, the mortar is simulated as line-distributed-diaphragm-flexure and dampers, the bridge is simulated as Euler beam. The vehicle is simulated as 6-freedom multi-body model. The equations describing the vertical vibration of the system are formulated on the basis of minimum potential theory and "sit in the right seat" principle, and simulating program is constructed accordingly with FORTRAN.On the basis of the vertical vibration model, the simply supported beam with 32m span to the qin-shen passenger dedicated line is set as an example, the vertical free vibration of the model is analyzed, the vertical free vibration frequency of the former six steps and some vibration mode are put forward. And the calculating results are proved to be correct and reliable. An analysis that contrasts the dynamic behavior of the train on the two common span used in the passenger dedicated lines is been done. The effect of the train formation, the spans with continuous arranged simply supported beams and the train running speed on the dynamic behavior of the vehicle is also been studied. In order to analyze and evaluate the dynamic properties of the transitional section between the embankments and bridges roundly, the distortion of the track is simulated as a cosine curve, with the vertical coupling vibration analysis model of the transitional section between the embankments and the bridges, the effect of the direction(get on or down the bridge),settlement diversity and the train running speed to the vehicle and the track construction of the transitional section between the embankments and the bridges are taken into account comprehensively, aiming at all kinds of condition, a mass of emulational calculation, comprehensive analysis and performance appraisement has been done, then the rule which all factors effect on the vehicle and the track is gained, the propositional value of the length of the transitional section between the embankments and bridges to different running speed is given, then some measure dealing with the problems about the transitional section between the embankments and bridges is summarized.