连续梁桥施工阶段地震响应及抗震性能评估

Seismic Response and Performance Assessment of Continuous Girder Bridge

采用桥梁专用分析软件,基于悬臂施工理论,结合一座多跨连续-刚构组合桥梁,选取变化比较复杂的施工阶段为研究对象,进行地震响应及抗震性能计算.结果表明,刚构梁段受力性能优于连续梁段,连续-刚构过渡梁段内力变化特殊;刚构梁段顺桥向、连续梁段横桥向抗震性能较好;结构横桥向塑性发展快于顺桥向,成桥时顺桥向、横桥向塑性区域发展最快.研究认为,同类结构设计时,需重视过渡梁段的受力变化,加强刚构梁段的横桥向、连续梁段的顺桥向抗震设计,避免桥墩基础过早的出现塑性区域;施工时需要注意刚构桥横桥向荷载作用,加强对边跨合龙阶段的观测.

Based on theory of cantilever construction, combined with a three cross continuous rigid frame bridge, with finite element analysis software, we select some complex construction phase as the research ob- ject, making calculation of seismic response and seismic performance. The results show that, when earthquake effects, rigid-framed girders＇ stress performance is better than that of continuous beam and the transition sec- tion is special; along the rigid-framed girder and transverse to the continuous girder, the seismic performance is good ; development of plastic transverse to the bridge is rapid, development of plastic of the complete bridge stage is rapid. Research suggests that, we need to strengthen the transition force changes of beam section, strengthen seismic design of transverse to rigid-framed bridge and along continuous beam bridge. During con- struction, we need to pay attention to loads of rigid-frame bridge, strengthen the observation of side span closure phase.