Seismic Analysis Of High-pier And Long-span Continuous Rigid Bridge

With the large size and varied topography of our country, many rigid frame bridges have been built with high piers and long spans. Furthermore, as railways and roads being built rapidly in the northwest and southwest regions, the heights of bridge piers constantly break the record level. As a result, the problem of the bridge seismic resistance design has aroused great concern among experts home and abroad for a long time. For the reason, this study intends to analyze the seismic response of some high-pier and long-span continuous rigid frame bridge with the finite element model created by means of MIDAS/CIVIL. It is hoped that the study results can be presented as a reference for the design of this kind of bridge. The main contents are as follows.Firstly, the study employs the orthogonality analysis method not only to analyze dynamic characteristics of variable parameters in some high-pier and long-span continuous rigid frame bridge, including the continuous length, the section flexural rigidity, the soil-pile effect and the pier height, but also to analyze the representative mode of vibrant. In addition, the study also uses the range analysis and the variance analysis to find the key parameters and to discuss the effect trend of various parameters on the mode of vibrant.Secondly, with the orthogonality analysis method, the study analyzes the responses of the bridge under uniform earthquake excitation. And based on the influence degree in the seismic response, four key parameters are sorted and their degree extent is discussed as well by means of the range analysis and the variance analysis.At last, the study analyzes the effect of middle seismic isolation technique on the seisic performance of continuous rigid-frame bridges as well, mainly focusing on three parameters. That is, the number of middle seismic isolation bearing in the pier, partion location and the curvature radius of friction pendulum bearing.