大跨桥梁结构地震反应分析及优化阻尼控制

对大跨桥梁结构进行地震反应分析及优化阻尼控制。考虑中间支承的弹性对桥梁结构地震反应的影响,提出在桥墩处设置集中旋转阻尼器,对阻尼参数优化,并给出一种新的旋转摩擦阻尼器的基本构造。采用离散元法将桥梁结构离散为具有n个刚杆且由(n+1)个弹性点元相连接的离散系统,并由Lagrange方程推导离散结构的运动方程。实例分析了一三跨等跨的连续桥梁结构,结果表明中间支承的弹性对地震反应有显著影响,施加优化阻尼控制后,其地震反应显著降低。

SEISMIC RESPONSE ANALYSIS AND OPTIMAL DAMPER CONTROL FOR LONG-SPAN BRIDGE STRUCTURES

In this paper the seismic response analysis and the optimal damper control for long-span bridge structures are performed, in which the influence of the elasticity of the middle supports on the seismic response of the structures is considered. The concentrated rotational dampers are proposed and placed at the supports, and their damping parameters are optimized. The fundamental construction of a new and efficient rotational friction damper is given. In the structural analysis, the Cell Discretization Method (henceforth C. D. M.) proposed recently is used, in which a bridge structure is reduced to a discrete system with n rigid bars connected by (n+1) elastic cells, and the equations of motion of the discrete system are deduced from the well-known Lagrange equation. Finally, a three-span bridge structure is numerically analyzed, and the results show that the elasticity of the middle supports notably affects the seismic response of the bridge, and the seismic response of the bridge can be significantly decreased under the optimal damper control.