A comparative study of passive control of structures

Abstract

Passive energy dissipation systems are described for the control of structures against earthquake vibrations. Classification of passive energy dissipation systems is made and discussion of the behaviour of individual passive devices and systems are provided. Hysteretic systems, viscoelastic systems, re-centering systems, dynamic vibration absorbers and base isolation system components are discussed. In order to investigate the effects of these systems on the response of structures, a typical model building is selected. Passive energy dissipation systems are applied to the model building and the results are then compared. First, in order to meet scientific objectives, a control theoretical four-story frame building was modelled without any passive energy dissipation systems. In a second model, isolators were used at the base level of the building. In a third, viscoelastic dampers are fixed at each storey. In the fourth model isolaters are at the base level together with viscoelastic dampers at each storey. In each scenario calculations have been carried out according to the equivalent seismic load method and linear time history analyses. Linear time history analyses have been carried out by simulating two earthquakes using 0.13sec. and 1.43sec. predominant periods and a 3.96m/sn² maximum acceleration. The different effects of the two periods are also presented. Results of base shears of the models, storey displacements, the bending moments at the top of the columns, and interstorey drift ratios are presented. Conclusions are drawn.