大跨度钢桁架拱桥的空间地震响应分析-中南大学学报.PDF

41 4 ( ) Vol.41 No.4 2010 8 Journal of Central South University (Science and Technology) Aug. 2010 (410075) 1/4 U448.224 A 1672−7207(2010)04−1590−07 Spatial seismic response analysis of long-span steel truss arch bridge CHEN Dai-hai, GUO Wen-hua (School of Civil and Architectural Engineering, Central South University, Changsha 410075, China) Abstract: Based on the analysis theory of seismic response for multi-freedom space system, a seismic response analysis procedure of long-span bridges was obtained and programmed with linear elastic finite element method. The procedures included finite element modeling, selection of ground motions and dynamic time-history analysis of the bridge and so on. A 3-span semi-supported continuous steel truss arch bridge, namely the Chongqing Chaotianmen Yangtze River Bridge, was taken as an example, the seismic characteristics of the bridge was investigated during uniform excitation and traveling wave excitation, respectively. The analysis results show that the maximal peak value of longitudinal displacement appears around the 1/4 of the center span for the arch rib of this bridge during uniform excitation, and the peak value of element internal force, which is around the left foot arch of the underlying arch rib, is maximal. The vertical earthquake ground motion and the tr