Long-period pulses in near-field earthquakes lead to large displacements in the base of isolated structures.To dissipate energy in isolated structures using semi-active control,piezoelectric friction dampers（PFD） ca...Long-period pulses in near-field earthquakes lead to large displacements in the base of isolated structures.To dissipate energy in isolated structures using semi-active control,piezoelectric friction dampers（PFD） can be employed.The performance of a PFD is highly dependent on the strategy applied to adjust its contact force.In this paper,the seismic control of a benchmark isolated building equipped with PFD using PD/PID controllers is developed.Using genetic algorithms,these controllers are optimized to create a balance between the performance and robustness of the closed-loop structural system.One advantage of this technique is that the controller forces can easily be estimated.In addition,the structure is equipped with only a single sensor at the base floor to measure the base displacement.Considering seven pairs of earthquakes and nine performance indices,the performance of the closed-loop system is evaluated.Then,the results are compared with those given by two well-known methods：the maximum possive operation of piezoelectric friction dampers and LQG controllers.The simulation results show that the proposed controllers perform better than the others in terms of simultaneous reduction of floor acceleration and maximum displacement of the isolator.Moreover,they are able to reduce the displacement of the isolator systems for different earthquakes without losing the advantages of isolation.展开更多
摩擦阻尼器结构简单、安装容易、性能稳定,具有广泛的应用领域。传统摩擦阻尼器,因阻尼力不具备调节能力,而只能对结构的振动产生有限的控制效果。压电材料和磁致伸缩材料分别具有在电场或磁场激励作用下的快速变形能力,是两类重要的智...摩擦阻尼器结构简单、安装容易、性能稳定,具有广泛的应用领域。传统摩擦阻尼器,因阻尼力不具备调节能力,而只能对结构的振动产生有限的控制效果。压电材料和磁致伸缩材料分别具有在电场或磁场激励作用下的快速变形能力,是两类重要的智能材料。利用以上两类智能材料制成的驱动器,调节摩擦阻尼器摩擦面的正压力,进而达到调节摩擦力的目的,是实现摩擦阻尼器智能化的重要途径。利用三个形状基本相同,材质分别为Terfenol-D金属、树脂基磁致伸缩复合材料以及压电陶瓷制成的驱动器,与同一参数的摩擦阻尼器复合,制成了三个阻尼力可调的智能摩擦阻尼器,并完成了它们的阻尼力及响应时间测试。结果表明,利用Terfenol-D驱动器复合的阻尼器(GMM摩擦阻尼器)具有最大的绝对出力和可调范围,利用树脂基磁致伸缩驱动器复合的阻尼器(GMPC摩擦阻尼器)次之,利用压电陶瓷驱动器复合的阻尼器(PZT摩擦阻尼器)最弱。GMM阻尼器和PZT阻尼器的响应时间分别在60 m s-80 m s以及30 m s左右。展开更多
文摘Long-period pulses in near-field earthquakes lead to large displacements in the base of isolated structures.To dissipate energy in isolated structures using semi-active control,piezoelectric friction dampers（PFD） can be employed.The performance of a PFD is highly dependent on the strategy applied to adjust its contact force.In this paper,the seismic control of a benchmark isolated building equipped with PFD using PD/PID controllers is developed.Using genetic algorithms,these controllers are optimized to create a balance between the performance and robustness of the closed-loop structural system.One advantage of this technique is that the controller forces can easily be estimated.In addition,the structure is equipped with only a single sensor at the base floor to measure the base displacement.Considering seven pairs of earthquakes and nine performance indices,the performance of the closed-loop system is evaluated.Then,the results are compared with those given by two well-known methods：the maximum possive operation of piezoelectric friction dampers and LQG controllers.The simulation results show that the proposed controllers perform better than the others in terms of simultaneous reduction of floor acceleration and maximum displacement of the isolator.Moreover,they are able to reduce the displacement of the isolator systems for different earthquakes without losing the advantages of isolation.
文摘摩擦阻尼器结构简单、安装容易、性能稳定,具有广泛的应用领域。传统摩擦阻尼器,因阻尼力不具备调节能力,而只能对结构的振动产生有限的控制效果。压电材料和磁致伸缩材料分别具有在电场或磁场激励作用下的快速变形能力,是两类重要的智能材料。利用以上两类智能材料制成的驱动器,调节摩擦阻尼器摩擦面的正压力,进而达到调节摩擦力的目的,是实现摩擦阻尼器智能化的重要途径。利用三个形状基本相同,材质分别为Terfenol-D金属、树脂基磁致伸缩复合材料以及压电陶瓷制成的驱动器,与同一参数的摩擦阻尼器复合,制成了三个阻尼力可调的智能摩擦阻尼器,并完成了它们的阻尼力及响应时间测试。结果表明,利用Terfenol-D驱动器复合的阻尼器(GMM摩擦阻尼器)具有最大的绝对出力和可调范围,利用树脂基磁致伸缩驱动器复合的阻尼器(GMPC摩擦阻尼器)次之,利用压电陶瓷驱动器复合的阻尼器(PZT摩擦阻尼器)最弱。GMM阻尼器和PZT阻尼器的响应时间分别在60 m s-80 m s以及30 m s左右。
