考虑摩擦效应的颗粒阻尼器力学模型研究及参数分析

颗粒阻尼具有高度非线性特性且影响因素复杂，在土木工程减振控制的研究和应用处于简单理论探究与实验阶段，尚未形成成熟可靠的理论对实际设计和应用进行指导。在阻尼颗粒未发生堆积时，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，并求得该力学模型在简谐激励下位移响应的解析解。该模型能够充分反映颗粒阻尼器的碰撞和非碰撞过程，其相轨迹可以体现颗粒阻尼器的复杂非线性特征。通过单层钢框架在简谐激励下的电磁振台试验对颗粒阻尼器的理论及运动特性进行验证，证明该理论模型的合理性和解析结果的正确性。最后对颗粒阻尼器进行颗粒质量、激振幅值、激振频率和阻尼颗粒运动间隙的参数分析，并与已有冲击阻尼器模型进行对比，结果表明所构建的力学模型能更加合理地评价颗粒阻尼器的减振性能。

MECHANICAL MODEL AND PARAMETER ANALYSIS OF PARTICLE DAMPER WITH CONSIDERING FRICTION EFFECT

The research and application of particle damper in civil engineering is simply in a theoretical and experimental stage because of the high nonlinear characteristics and complex factors, and no more mature and reliable theory has been formed to guide the design and application in actual civil engineering. When the damping particles are not accumulated, considering the collision process and friction effect between particles and chamber, a mechanical model of particle damper-SDOF system is constructed. The analytical solution of the displacement response of the theoretical model under harmonic excitation is obtained. The mechanical model could fully reflect the collision and non-collision process of particle dampers, and the phase trajectories could reflect the complex nonlinear characteristics of particle dampers. The rationality of the model and the correctness of the analytical results are proved by the verification of the hypothesis of the particle damper and the electromagnetic shaking table test of a single steel frame under simple harmonic excitation. Finally, the parameters of the particle dampers are analyzed in terms of particle size, excitation amplitude, excitation frequency and damping particle motion gap. Moreover, compared with the existing model of impact dampers, the results show that the mechanical model is more reasonable for evaluating the damping performance of particle damper.