Flutter is a critical point of concern in the wind-resistant design of long-span suspension bridges. As a novel realization, the multi-tower suspension bridge is becoming more and more popular in engineering communities. The aeroelastic stability of this kind of bridge attracts intensive attentions. To better understand the flutter performance of multi-tower suspension bridges, a long-span quadruple-tower suspension bridge (QTSB) with three main spans is designed in this study by extension from Taizhou Bridge, which is a triple-tower suspension bridge (TTSB) with double main spans. Considering the role of some important structural parameters in flutter performance, a parametric analysis is carried out for the long-span QTSB with comparisons to the TTSB that has the same length in each main span. The parameters of focus include sag-to-span ratio of the main cable, vertical and torsional rigidities of the girder, mass of the girder as well as longitudinal rigidities of middle towers. The analytical results indicate that increasing the torsional rigidity of the girder and longitudinal rigidities of middle towers can effectively improve the critical wind velocities. Changing the sag-to-span ratio or the mass of girder would cause complicated results, in which the transition of the dominant mode is observed. The mode transition phenomenon can be reasonably utilized in the wind-resistant design of a long-span QTSB.

在大跨度悬索桥的抗风设计中，颤振是至关重要的问题。作为一种新颖的实现方式，多塔式悬索桥在工程界变得越来越受欢迎。这种桥梁的气动弹性稳定性引起了广泛的关注。为了更好地理解多塔悬索桥的颤振性能，本研究在台州桥的基础上设计了三跨度的大跨度四塔悬索桥（QTSB），该桥是三塔悬索桥（TTSB） ），并具有双主跨度。考虑到一些重要的结构参数在颤振性能中的作用，对大跨度QTSB进行了参数分析，并与每个主跨度中具有相同长度的TTSB进行了比较。焦点参数包括主缆的下垂比，梁的垂直和扭转刚度，梁的质量以及中塔的纵向刚度。分析结果表明，提高梁的抗扭刚度和中塔的纵向刚度可以有效地提高临界风速。改变下垂比或梁的质量会导致复杂的结果，其中观察到主导模式的转变。模式转换现象可以合理地用于大跨度QTSB的抗风设计中。分析结果表明，提高梁的抗扭刚度和中塔的纵向刚度可以有效地提高临界风速。改变下垂比或梁的质量会导致复杂的结果，其中观察到主导模式的转变。模式转换现象可以合理地用于大跨度QTSB的抗风设计中。分析结果表明，提高梁的抗扭刚度和中塔的纵向刚度可以有效地提高临界风速。改变下垂比或梁的质量会导致复杂的结果，其中观察到主导模式的转变。模式转换现象可以合理地用于大跨度QTSB的抗风设计中。