大跨度上承式钢桁拱桥的地震响应分析

Seismic response analysis of long-span steel braced deck-type arch bridge

对研究大跨度上承式钢桁拱桥在地震激励作用下的响应特性进行了研究。采用时程分析法计算了上承式钢桁拱桥在纵向、纵+竖、三维激励作用下的内力响应,分析了纵向、竖向、横向激励作用下上承式钢桁拱桥的响应特性,讨论了行波效应对钢桁拱肋地震响应的影响,对桥面系支座布置方式的影响进行了对比分析。结果表明:拱脚是上承式钢桁拱桥在地震作用下的危险截面,行波效应显著增大了拱肋内力,桥面支座的布置方式是影响拱肋内力响应的重要因素。

The seismic response behavior of long - span steel braced deck - type arch bridge was investigated. The interior force response of steel braced deck - type arch bridge subjected to longitudinal excitation, longitudinal ＆ vertical excitation, three- dimension exaction was calculated by time - history analysis method. The seismic response behavior of braced deck - type arch bridge subjected to longitudinal excitation, vertical excitation and lateral excitation was analyzed. The effect of travel wave was discussed. The influence of deck support manner was contrasted. The results show that arch end is critic section of steel braced arch bridge subjected to seismic excitation and the arch rib interior force increases obviously due to travel wave effect. The collocation of deck support is important to arch rib interior force.