Seismic Behaviour and Capacity Demand Analysis of a Double Deck Bridge

摘要

This paper presents a comprehensive analysis on the seismic response of a doubledeckrnbridge in China. A 3-D model was developed for a curved double-deck bridge,rnand a linear dynamic analysis (response spectrum analysis) has been used tornevaluate the seismic vulnerability of this bridge through the capacity/demand (C/D)rnratio analysis of the structural elements. Then a further parametric study wasrnconducted to investigate the effect of different structural irregularities in terms of thernnon-uniform foundation conditions, the length of the lower columns of the bents,rnand also the irregular column length within the same bent. Three series of modelsrnincluding the regular, semi-regular, and irregular ones were employed for this study.rnThe results indicate that the seismic response of the double-deck bridge, in a largerncontent, depends on the foundation conditions, the shape of the bridge, the length ofrnthe pier bent’s columns, and the degree of the column’s length irregularity.