基于能量法的颗粒阻尼器减振机理研究及参数分析

Parameter analysis and research on the vibration damping mechanism of particle damper based on energy theory

颗粒阻尼技术因频带宽和鲁棒性强等优点在土木工程减振领域具有良好的应用前景,但由于颗粒的力学行为具有高度非线性特征且影响因素复杂,相关力学机理研究尚不深入,亟需改进.在阻尼颗粒未发生堆积的条件下,考虑阻尼颗粒与阻尼器腔体之间的碰撞过程和摩擦效应,构建一种颗粒阻尼器-单自由度结构系统力学模型.基于能量法对颗粒阻尼器-单自由度结构各组分能量进行求解,对结构系统各部分耗能规律进行分析,明晰减振机理,对颗粒阻尼器和TMD的减振效果进行对比并探究颗粒材料参数影响规律.通过单层钢框架电磁振动台试验验证基于能量法的结构动力分析的准确性.结果表明:在同等条件下,当结构发生共振时TMD的减振效果较优,非共振时颗粒阻尼器的减振效果较优;在非共振条件下,颗粒阻尼器的减振效果随碰撞恢复系数的减小或滚动摩擦系数的增大而增加,小粒径阻尼颗粒的减振效果更优.

Particle damping technology has many application prospects in the field of civil engineering due to its advantages of wide working frequency bands and strong robustness. However, the mechanical behaviors of the particles are highly nonlinear and their working mechanism is very complex, which is up to now not well revealed and need urgently to be improved. Consid-ering the collision process and friction effect between the damping particles and the damper cavity for the case that the damping particles do not accumulate, a mechanical model of particle damper is constructed. First, the energy method is used to solve the energy of each component of the SDOF system with particle damper. The energy consumption rule of each part of the structural system is analyzed carefully, and the damping mechanism is clarified. Then, the damping effect of the particle damper and TMD is compared, and the influence of the particle material parameters is explored. The accuracy of the structural dynamic a-nalysis based on energy method is verified through the electromagnetic shaking table test of a single-layer steel frame. The re-search results show that the damping effect of TMD is better when the structure resonance occurs, and the damping effect of the particle damper is better for non-resonant case. Under non-resonant conditions, the damping effect of the particle damper increases with the decrease of the impact recovery coefficient or with the increase of the rolling friction coefficient. It also shows that the damping particle with smaller radius has better damping effect.