Abstract

Using the nonlinear dynamic analysis program DRAIN-2DX, a detailed investigation for a one-story single-degree-of-freedom steel moment-resistant frame and a ten-story multi-degree-of-freedom steel moment-resistant frame with and without added dampers is performed. Three types of dampers - friction damper, viscoelastic damper and fluid viscous damper - are investigated. Comparisons of each damper under far-fault and near-fault ground motions are carried out. It is found that, when subjected to the same peak acceleration of ground motion, the dynamic responses of all damped structures under near-fault earthquakes with high pulse-type velocity are generally stronger than those under far-fault earthquakes. Moreover, from the energy point of view, comparison of effectiveness of different dampers subjected to earthquakes is performed. It is found that the friction-damped structure is relatively more effective than the other two dampers when subjected to selected earthquake records. However, the difference in the effectiveness among the three dampers is not large, which shows that all three types of dampers can be used to mitigate structural dynamic response effectively.