Stability Analysis on Middle Steel Pylon of Taizhou Yangtze River Bridge

Stability of the steel middle pylon is a significant issue to be discussed for Taizhou Yangtze River Bridge. With consideration to the middle pylon initial deficiency and integration-region related bucking, a finite element analysis is performed to simulate the stability of the middle pylon. Firstly, a total bridge frame model is established for elastic and elastic-plastic analysis. Secondly, shell element is introduced for detailed simulation of the pylon and combined with beam element to establish the total bridge model. According to the analysis results, the initial deficiency has no significant impact on the analysis results. Elastic-plastic stability analysis of frame model shows the stability safety factor of middle pylon is 2.417 in the most unfavourable situation, much less than the result of elastic analysis. Analysis adopting hybrid model presents result consistent with the frame model, and demonstrates both the local and entire instability process clearly.