RESEARCH ABOUT THE INFLUENCING FACTORS ON THE MECHANICAL CHARACTERISTICS OF THE WELDED CROSSOVER ON BRIDGE FOR PASSENGER DEDICATED LINE UNDER TEMPERATURE AND VEHICLE LOAD

With the restrictions of environmental protection, geological and topographic conditions, elevated stations would appear in passenger dedicated lines. The single crossover is always laid in throat zone of the elevated stations and the welded crossover on bridge with bridge structure is formed. The mechanical characteristics of the welded crossover on bridge are complicated, which are necessary to be researched. In this paper, a longitudinal-lateral-vertical coupled spatial calculation model of No.18 ballastless track welded crossover on bridge is established by adopting finite element method. Some main factors that affect the mechanical characteristics of welded crossover on bridge are researched and analyzed, which include relative location of crossover, bridge format and span length of bridge. The results show that: (1) the welded crossover is suitable to be placed close to the fixed bearings of bridge, which is favorable for lowring force and displacement of structure; (2) to ensurue the integrity of structure, continuous beam bridge should be adapted in the arrangement of welded crossover; (3) the increase of span length is adverse for keeping the geometrical form and position of the welded crossover on bridge, therefore the span length of continuous beam bridge for laying welded crossover shouldn't be too large. According to the research results, suggestions on the design of welded crossover on bridge for passenger dedicated line are put forward.