Abstract:Research purposes: As the tie -arch bridge uses tie bar to bear the push force of the arch, so it is one of reasonable bridge types under the condition the bridge height is limited or the bridge site lies in the unfavorable geological area. The supermajoroverpass on the 3rd ring road in Chengdu is the first and largest large -span double track railway prestressed concrete tied arch bridge inChina. In thispaper, the research isdonemainly on the structural features and the characteristics of force bearing capacity of such tied arch bridge for instructing the construction.
Research conclusions:The the static and dynamic analysesof the supermajoroverpasson the 3rd ring road in Chengdu show that all indexes of the bridge meet the code requirements. As the bearing force at joint point of arch beam is complicated, the three -dimensional prestressed structure should be designed, the beam end ofmain beam should be widened and heightened, andwebs should be thickened. The stress concentration happens in some partsbecause of the complicated structure. Based the research and calculation, the applicable range of tied arch structure in construction of railway bridge iswidened by adopting new scientific research achievements and theories athome and abroad and it can provide the reference to the similar works.