基于IDA的套箍加固拱上立柱抗震性能评估

Seismic performance of spandrel columns strengthened by jackets based on the incremental dynamic analysis

以德阳金花大桥为工程实例,结合拱上立柱的实际震害,利用地震作用下的非线性计算模型,建立基于IDA的钢筋混凝土套箍加固拱上立柱抗震性能评估分析方法。通过分析表明,剪跨比对拱上立柱的抗震性能影响显著,高剪跨比立柱抗震性能相对较差,在地震作用下拱上立柱为易损构件;套箍加固拱上立柱的抗震性能提高明显,易损性显著降低,延性亦有一定程度改善。分析结果与震害调查具有一致性,可为拱上立柱抗震评估提供参考。

The Jinhua Bridge in Deyang City was taken as an example to analyze the actual seismic damage of spandrel columns,then using the nonlinear calculation model under the action of earthquake,an IDA-based method for evaluating the seismic performance of spandrel columns strengthened by reinforced concrete jackets was established.The analysis results showed that the shear-span ratio has a significant effect on the seismic performance of spandrel columns.The column with high shear-span ratio is relatively poor in seismic performance,and the spandrel column is a vulnerable component under earthquake action.The seismic performance of spandrel columns strengthened by jackets is improved obviously:the vulnerability is significantly reduced,and the ductility is improved to a certain extent.The analysis results are consistent with those of seismic damage survey,which can provide a reference for the seismic evaluation of spandrel columns.