多联连续梁桥横桥向多模态推倒分析方法

Modal Pushover Analysis Method in Transverse Direction of Multi-span Continuous Bridges

研究多联连续梁桥横桥向的多模态推倒分析(MPA)方法,用于初步设计阶段的抗震性能评估,并进一步对比分析了Luca折线简化方法与FEMA 356中折线简化方法应用于多模态推倒分析方法中的效果.以某三联主线桥为研究对象,进行多模态推倒分析和非线性动力时程分析.结果表明:多模态推倒分析方法可以对多联连续梁桥的抗震性能做出有效评估,Luca折线简化方法与FEMA 356中的折线简化方法相比优越性不明显.

Modal pushover analysis method in transverse direction of multi-span continuous bridges is studied for seismic performance evaluation of bridges in preliminary design stage. Moreover, effects of near-optimal piecewise linear fits and FEMA-356 fits in modal pushover analyses are compared. Modal pushover analyses with the two fits and nonlinear time-history analysis of 3 continuous units of a constructing bridge are conducted. The conclusions are drawn that the modal pushover analysis method reasonably predicts the seismic performance of multi-span continuous bridges; no obvious advantages of near-optimal piecewise linear fits are shown in comparison with FEMA-356 fits.