相邻结构减震体系参数随机性影响分析

Effects of Parameter Randomness on Adjacent Structures Linked by Viscous Dampers

根据黏滞阻尼器连接相邻结构减震体系的2-DOF模型,以平稳白噪声为地震激励,建立了结构振动能量表达式,分别以单体塔楼和整体结构的振动能量最小为控制目标,建立了优化连接阻尼参数理论表达式。分析了结构频率比和质量比的随机性对优化连接阻尼、结构减震效果的影响以及连接阻尼参数随机性对减震效果的影响。最后对某工程算例进行了位移反应分析,对比了减震效果。结果表明,依据简化模型得到的优化连接参数可以适用于多自由度体系,两结构频率比的随机性对优化连接参数及减震效果有一定影响,质量比的随机性对二者影响较小,而优化连接阻尼随机性对减震效果的影响则可以忽略不计。

Based on a 2-DOF model of adjacent structures connected by viscous dampers, the time-averaged total vibration energy was derived with the white noise as the earthquake excitation. The analytical formulas to determine the optimum parameters of viscous dampers that link adjacent structures were presented with the ob- jective of achieving the minimum vibration energy of the independent monomer tower or the integral structures. Effects of the structural vibration frequency ratio （VFR） randomness and mass ratio （MR） randomness on damping coefficient （LDC） optimization, seismic mitigation effectiveness were studied. The LDC randomness effects on seismic mitigation were also discussed. The tip displacement of the damper-connected adjacent structure was comparatively examined. It is found that the optimum connecting parameter derived from the sim- plified model is applicable for seismic reduction design. The results also indicate that the VFR randomness has obvious influence on the optimum LDC and seismic mitigation effectiveness but MR randomness has insignifi- cant influence. Moreover, the effects of optimum LDC randomness on seismic reduction effectiveness can be neglected.