并联式单向单颗粒阻尼器力学模型及优化分析

针对目前颗粒阻尼器的不足及土木工程减震的需求，提出并联式单向单颗粒阻尼器(Parallel Single-Dimensional Single Particle Damper, PSSPD)。在剖析PSSPD减振机理且全面考虑颗粒的受力状态的基础上，建立其力学模型并提出一种高效的变步长数值计算方法。针对简谐激励，获得PSSPD-单自由度结构系统处于稳定、对称、周期碰撞状态时的系统位移响应解析表达，并在该结果的基础上分析各参数对PSSPD性能的影响及颗粒运动最优间距的与其它参数的关系，对其准确性进行验证。提出PSSPD在地震动中的优化分析方法并对其合理性和准确性也进行验证，并研究在最优设计参数和不同场地地震动作用下PSSPD对结构的减震效果。结果表明:因PSSPD属于加速度(力)相关性阻尼器，只要颗粒发生碰撞就会转移受控结构的能量，而地震动频谱的丰富性和随机性增强了颗粒发生碰撞的概率，PSSPD对不同场地下的地震动均有良好的减震效果，且场地效应对其减震效果影响不明显，更加适用于中低层结构。

MECHANICAL MODEL AND OPTIMAL ANALYSIS OF PARALLEL SINGLE-DIMENSIONAL SINGLE PARTICLE DAMPER

Aiming at the shortcomings of current particle dampers and the need for seismic absorption in civil engineering, a parallel single-dimensional single particle damper (PSSPD) is proposed. Considering the damping mechanism and the stress state of particles, the mechanical model of PSSPD is established and its numerical analysis method is put forward. The analytical expression of displacement response of PSSPD-SDOF in stable, symmetrical and periodic collision state is obtained under harmonic excitation. Based on this result, the influence of each parameter on the performance of PSSPD and the relationship between the optimal distance of particle motion and other parameters are analyzed, and its accuracy is verified. Then, the optimization analysis method of PSSPD in ground motion is put forward, and its rationality and accuracy are verified. Immediately, the effect of PSSPD on the structure under the optimal design parameters and different ground motions is studied. The results show that as a PSSPD belongs to an acceleration (force)-dependent damper, the energy of a controlled structure will be transferred if the particle collides, and the randomness of seismic spectrum enhances the probability of particle collision. A PSSPD has a fine damping effect for ground motions of different site types, and the site effect on damping ration is not significant. A PSSPD is more suitable for a middle and low-rise structure.