斜拉桥拉索地震响应分析

Study on cable response of cable-stayed bridge due to earthquakes

为了研究斜拉桥拉索在地震作用下的动力响应,以某斜拉桥为工程背景,采用MIDAS CIVIL软件,建立了全桥有限元模型,输入3条E2水平下的安评地震波,通过时程分析方法探讨了粘滞阻尼器对斜拉索地震响应的影响,讨论了最不利索梁锚固位置和最不利拉索位置。结果表明:与水平面的夹角约为33°的拉索为最大拉力索、其为最不利锚固索,研究结论与已有震害相符;与水平面夹角约为38°的拉索为最大拉应力索、其为最不利受力索。研究成果可供斜拉索抗震设计时参考。

In order to study the cable response of cable-stayed bridges under the action of earthquakes,a finite element model of a cablestayed bridge is established by MIDAS CIVIL software as the engineering background.The effect of dampers on seismic response of cables is discussed by time history analysis method using three E2 level seismic waves as input ground motions.The most unfavorable cable-girder anchorage position and the most unfavorable cable position are discussed.The results show that the cable with an angle of about 33°to the horizontal plane is the maximum tension cable and the most unfavorable anchorage cable under the action of earthquake.The conclusion of the study is consistent with the existing earthquake damage.The cable with a horizontal angle of about 38°is the maximum tensile stress cable,which is the most unfavorable stress cable under the action of earthquake.The research results can be used as reference for the anti-seismic design of stay cables.