多塔矮塔斜拉桥结构参数敏感性分析
Analysis of structural parameters of multi-span extra-dosed cable-stayed bridge

基于结构参数敏感性分析的摄动原理，通过选择合适的摄动值计算各参数对结构力学性能的敏感系数，研究多塔矮塔斜拉桥参数变化对结构内力、变形和自振特性的影响大小，为结构设计和施工监控提供参考。研究结果表明：边跨长、主梁刚度、桥墩刚度的变化对结构刚度和内力影响较大，拉索刚度、跨中无索区长度对结构内力的影响相对较小；塔跨比、拉索刚度、主梁刚度是影响索力的主要因素；主梁和桥墩刚度、边跨长度对主梁振型的影响较大；塔跨比、主塔刚度则对主塔的振型有较大影响。
Based on the perturbation principle, a Multi-tower extradosed cable-stayed bridge was conducted to study the influence of structure parameters on internal force, deflection and vibration characteristic by choosing the appropriate perturbation values and calculating the sensitivity coefficients. The calculation results show that the side span length, girder stiffness and pier stiffness largely affect the structural stiffness and internal force. The change of the cable stiffness and the length without cable in mid-span have little effect on structural internal force. The tower-span ratio, cable stiffness and girder stiffness are the main factors affecting the cable force. The girder and pier stiffness, side span length of the girder affect the vibration mode of the girder greatly. The tower-span ratio and the stiffness of pylon have great influence on the mode of pylon vibration. The conclusions of this paper can provide reference for structural design and construction monitoring