Analysis of Rigidity of Multi-Pylon Cable-Stayed Bridges

With the growing construction of multi-pylon cable-stayed bridges at home and abroad,the numbers of the pylons used for such type of the bridges and the spacing distances among the pylons constantly increase.The way of how to ensure the global rigidity of the bridges becomes a critical issue confronted in development of the structural systems.On the basis of analysis of the structural characteristics and mechanical behavior of the bridges,the factors having influences on the global rigidity of the bridges having 3 pylons,4 pylons and more than 4 pylons are analyzed from three aspects of the rigidity of pylon,stay cable and girder,setting of auxiliary structure and utilization of extradosed bridge.The measures for improving the rigidity of the bridges having been completed and being constructed at home and abroad are compared and summarized and the effective method for improving the rigidity of the bridges having different numbers of the pylons is obtained.The method herewith may provide technical reference for design and construction of the multi-pylon cable-stayed bridges in the future.