中文摘要：

为研究大跨径三塔自锚式悬索桥结构各主要设计参数对动力特性的影响,以滨河黄河大桥为背景,采用MIDAS/Civil建立动力有限元模型,分析了垂跨比、恒载集度及构件刚度等参数对结构动力特性的影响规律.分析结果表明：结构的振型排列非常密集,抗震分析时应考虑高阶振型的影响;采用叠合梁形式的加劲梁有利于结构的抗风稳定性;增加垂跨比有利于提高结构的抗风稳定性;恒载集度的提高会降低加劲梁的纵飘、竖弯及扭转振型频率;主缆抗拉刚度主要对加劲梁的竖向振动产生影响;增大边塔纵向抗弯刚度能够有效减小加劲梁的纵向地震位移响应;而中塔纵向抗弯刚度、垂跨比及加劲梁的抗弯、抗扭刚度对加劲梁纵飘振型频率影响甚小.

英文摘要：

To study the influences of the main design parameters on the dynamic characteristics of of a long span triple-tower self-anchored suspension bridge, the main bridge of Binhe Yellow River Bridge is taken as an example and a dynamic finite element model for the bridge is established based on the software MIDAS/Civil The influences of the parametric variations of the rise-span ratios, dead load intensity and structural, stiffness on the dynamic performance of the bridge are analyzed. The results demonstrate that the vibration modes of the bridge are densely arrayed. The effect of high-order modes on the seismic response of the bridge should be taken into account. It is beneficial to improving the wind resistance stability of the structure by using stiffening girder of composite beam. Increasing the vertical span ratio is beneficial to improving the stability of the wind resistance of the structure. Increasing the rise-span ratios contributes to the improvement of the wind stability of the structure. The increase of the dead-load will reduce vibration frequency of the longitudinal drift, vertical bending and torsional of the stiffening girder. The tensile stiffness of the main cable mainly affects the vertical vibration of stiffening girder. Increasing the longitudinal bending stiffness of the side tower can effec- tively reduce the longitudinal displacement of the stiffening girder seismic response. The longitudinal bending stiffness of the mid-tower, the rise-span ratios, the bending and torsional stiffness of stiffe ning girder have barely influence on the longitudinal drift of stiffening girder.