斜拉桥粘滞阻尼器设计方案及参数回归分析

Design Schemes and Parameter Regression Analysis of Viscous Dampers for Cable-Stayed Bridge

为优化粘滞阻尼器对双塔斜拉桥的减震效果,以淮安大桥(主跨为416m的双塔斜拉桥)为背景进行研究。采用有限元软件SAP2000建立全桥三维有限元模型,应用非线性动力时程方法对比分析了4种不同阻尼器布设方案(分别将粘滞阻尼器布设在塔支座、桥台、边墩和桥台、边墩位置)的减震效果。选择最优方案进行阻尼参数分析,应用最小二乘回归分析法建立关键截面参数与阻尼参数之间的数学模型,以控制截面内力和变形最小为原则,通过求解拟合方程的极值得到最优设计参数。结果表明:在桥台位置安装粘滞阻尼器能使其更好地发挥减震功能,且不改变辅助墩的受力;所提出的阻尼参数优化设计方法能有效地计算出最优阻尼参数,为设计提供方便。

To optimize the damping effect of the viscous dampers used for double-pylon cablestayed bridge, the Huai＇an Bridge （a double-pylon cable-stayed bridge with a main span of 416 m） was cited as an example for study. The software SAP2000 was used to establish the three-dimensional finite element model for the whole bridge of the bridge and the damping effect of 4 different layout schemes of the viscous dampers （the dampers were to be respectively laid out at the locations of the pylon bearings, abutment, side pier plus abutment and side pier） was comparatively analyzed by the nonlinear dynamic time-history method. The optimal layout scheme was chosen and the parameters of the viscous dampers were analyzed. By the least square regression analysis method, the mathematical model for the parameters of the critical sections and the damp- ers was created and on the principle of controlling the internal forces and deformation of the sec- tions to the minimum, the optimal design parameters were obtained through solving the extreme values of the fitting equations. The results of the study show that the scheme of installing the viscous dampers at the abutment of the bridge can result in better damping function of the dampers and will not change the stress of the auxiliary piers. The proposed optimal design method for the parameters of the dampers can be used to effectively calculate the optimal parameters of the dampers and will hence provide convenience for the design.