基于复阻尼理论求解等效粘滞阻尼比,以近似描述非经典阻尼体系的阻尼耗能特性,提出了考虑实测阻尼值修正的具有非经典阻尼特性的双链式悬索桥地震响应分析方法。结合一双链式悬索桥,对比分析经典阻尼及非经典阻尼对双链式悬索桥地震响应的影响。研究结果表明:非经典阻尼对双链式悬索桥的地震响应有明显的影响,用经典阻尼模型得不出可靠的解,双链式悬索桥的地震响应分析,应当使用非经典阻尼模型;在初步分析时,纵、竖向地震下非经典阻尼体系的地震响应可分别按全桥混凝土桥塔阻尼比、钢加劲梁阻尼比计算结果代替,以简化计算。
Based on the complex damping theory to get the equivalent viscous damping ratio, which was used to describe energy dissipation characteristics of non - classical damping system approximately, a method was proposed to analyze seismic response of double chains suspension bridge considering non- classical damping modified by measured value. Through an example of double chains suspension bridge, the influence of different damping forms on seismic response of double chains suspension bridge was analyzed, which considering classical damping and non - classical damping respectively. The results show that non - classical damping has a significant effect on the seismic response of double chains suspension bridge, and response based on the classical damping model is not reliable. Non - classical damping model should be used in seismic analysis of double chains suspension bridge, however, the seismic response of non - classical damping system under the longitudi- nal or vertical seismic wave can be substituted approximately by the seismic response calculated according to damping ratio of concrete tower and steel stiffening girder respectively, which can simplify the calculation during preliminary analysis.