【摘要】 为研究竖向地震作用下大跨径碳素纤维复合材料(CFRP)悬索的水平张力增量随跨径和垂跨比的变化,基于线性自由振动理论推导了悬索强迫振动方程,进一步得到了用于近似求解张力增量的振动参数αn,采用极限设计原则计算两种桥型的CFRP悬索静力参数,通过αn研究水平张力增量的变化。研究表明:CFRP悬索跨径变化对αn几乎不影响,而垂跨比对αn影响非常大。当不考虑背索时,二阶振型所产生的张力增量为悬索张力增量的主要贡献;当考虑背索时,主要由一、二阶振型控制悬索张力增量的变化。更多还原

【Abstract】 In order to study the variation of the horizontal additional tension of the large-span CFRP cable under the ver-tical seismic action with the change of the span and sag-span ratio, aforced vibration equation for a suspended cable isderived based on the linear free vibration theory. Further more, a vibration mode parameterαnis obtained for the approx-imate analysis of the additional tension. The calculation of the parameterαnwhich is used to research the variation of thehorizontal additional tension is based on the static parameter, calculated by limit design principle, of the CFRP suspen-ded cable for two kinds of suspension bridge. The result demonstrateed that the change of the span of CFRP cable hadhardly influence on the parameterαnand a small change of the sag-span ratio obviously affectsαn, The second vibrationmode was the main mode contributing to additional tension of suspended cable for the situation without the backstay. Inaddition, with the increase of the sag, the third mode should be considered also for its contribution to the additional ten-sion. When the suspended cable had the backstay, the first two modes contributed the majority of the additional tension.However the contributions were affected by the sag ratios.更多还原