Structural Analysis In Design Of Urban Cable-Stayed Bridge With Inclined Pylon And Hybrid Girder

Recently, the cable-stayed bridge with inclined pylon stands out from urban bridges in the condition of small span and wide deck because of its original pylon and graceful modeling. The bridge with hybrid girder attracts more and more attention of designers because of its strong spanning capacity, full use of material and short construction period.WenboLu Reservoir Bridge was chosen as the study case. Space bar FEM model of whole bridge was established with MidasCivil software to analyze the static and stable performance of the bridge. It was indicated that temperature gradient along cross section of the beam has a significant effect on the stress of concrete beam in such bridge. The pylon was designed quite thick because of the large moment on the inclined pylon, so the pylon is difficult to lose its stability. Meanwhile the stability safety coefficient of the beam is large. Therefore, the use of hybrid girder and inclined pylon can effectively improve the stability of cable-stayed bridge.The seismic performance can be improved by using hybrid girder, but the use of inclined pylon make against the seismic behavior of the structure. The seismic response of the bridge was analyzed on the basis of response spectrum theory and time-history method. The pylon can be considered as the weak link in the seismic design of structure. The bottom of pylon is at risk of damage when E2 earthquake occurs.The local model of the steel box girder was established with ANSYS software to analyze the second and third system stress of orthotropic steel deck. In ord to confirm the most unfavorable loading scheme of the wheel, an evaluation system based on the influence rating coefficient was put forward. Discrete comparison analysis was studied by considering different parameters on the most unfavorable loading scheme. Such parameters included thicknesses of upper plate, longitudinal rib and diaphragm. The significance of transverse effect in urban cable-stayed bridge with wide deck was revealed in the study. Transverse stress of the steel deck can be efficiently reduced by thickening the diaphragm properly.