连续弯箱梁自行车桥地震响应分析

Seismic Response of Bicycle Bridges with Continuous Curved-Box Girder

为研究厦门市弯箱梁自行车桥的地震响应规律,采用SAP2000有限元软件建立自行车高架桥三维壳体模型,在考虑多遇地震和罕遇地震水准作用及不同加载方向的基础上,分别采用反应谱分析法和时程分析法进行该桥的动力响应分析。结果表明:自行车桥z方向位移分量最大,且z方向分量极值均发生在曲线分叉段;相对剪力而言,桥墩竖向支反力相对较小;E1和E2地震水准响应情况随时间的变化趋势基本一致,桥梁结构未进入塑形状态,抗震性能良好,安全性指标较高;反应谱法计算得到的响应包络值相对3条不同的地震时程结果的峰值大,在实际桥梁抗震分析过程中需要综合考虑两者的分析结果。文章研究结果对今后自行车桥设计和抗震性能分析具有指导意义,并可为研究者对该类桥的进一步研究提供借鉴。

To study the seismic response law of the curved-box-girder bicycle bridge in Xiamen city,we established a three-dimensional shell model of the bicycle viaduct using SAP2000 finite element software.We calculated the dynamic response of the bicycle viaduct using the response spectrum and time-history analysis methods after considering the effects of frequent and rare earthquakes and different loading directions.The results show that the Z-direction displacement component of the bicycle bridge is the largest,with the extreme value of the Z-direction component occurring in the curve bifurcation section.The vertical support reaction of the pier was found to be small relative to the shear force.The results also indicate that the variation trends of the seismic responses of E1 and E2 are basically the same with time,the bridge structure does not enter the plastic state,and the seismic performance is good.The envelope value calculated by the response spectrum method is larger than the peak value of the time-history results for three different seismic waves.In the actual seismic analysis process,it is necessary to consider the analysis results of both methods.The results of this study have great significance for guiding the future design and seismic performance analysis of bicycle bridges and as a reference for further research on this kind of bridge.