连续刚构桥地震响应灰色关联参数敏感性分析

Parameter Sensitivity Analysis of Seismic Response of a Continuous Rigid Frame Bridge based on Grey Correlation Method

为进一步研究连续刚构桥的地震响应规律,以某连续刚构桥为例,建立了不同工况下连续刚构桥数值计算模型,充分考虑负相关因素,采用基准值误差与改进的灰色T型关联分析方法,以地震作用下某连续刚构桥墩顶顺桥向弯矩、墩底横桥向弯矩、墩底顺桥向弯矩和跨中横桥向弯矩为评价指标,进行了地震作用下连续刚构桥灰色关联参数敏感性分析。分析结果表明:高墩墩顶顺桥向弯矩对梁底曲线幂次的变化更敏感,矮墩墩顶顺桥向弯矩对根部梁高高跨比的变化更敏感,而墩底顺桥向弯矩则对墩高比的变化更敏感;高墩墩底横桥向弯矩对跨中梁高高跨比的变化更为敏感,矮墩墩底横桥向弯矩则对根部梁高高跨比相对更敏感;主梁跨中横桥向弯矩则对跨中梁高高跨比的变化更为敏感。该敏感性分析方法,可为连续刚构桥抗震设计及防灾减灾提供一定参考。

In order to further study the seismic response law of continuous rigid frame bridge,the numerical calculation models of continuous rigid frame bridge under different working conditions are established. To fully consider the negative correlation factors,the longitudinal bending moment at pier top and pier bottom and the transverse bending moment at pier bottom and middle span are selected as seismic response indexes to carry out parameter sensitivity analysis based on the fiducial error analysis method and modified T’s grey correlation analysis method. The computational results show that the longitudinal bending moment at the high pier top is more sensitive to the power curve of beam bottom,while the longitudinal bending moment at the low pier top is more sensitive to the high-span ratio at root of the beam,and the longitudinal bending moment at the pier bottom is more sensitive to the pier height ratio.Besides,the transverse bending moment at the high pier bottom is more sensitive to the high-span ratio of the beam at the middle span,while the transverse bending moment of the low pier bottom is more sensitive to the high-span ratio at root of the beam,and the transverse bending moment at midspan of the girder is more sensitive to the high-span ratio of midspan beam. The presented procedure of sensitivity analysis method can provide reference for seismic design of continuous rigid-frame bridges as well as disaster prevention and mitigation.