Seismic Behavior of Steel Frames Equipped with Comb-Teeth Metallic Yielding Dampers

Comb-teeth damper (CTD), is a new type of metallic yielding damper, which is made of steel plates and includes a number of teeth that dissipate energy through in-plane flexural yielding. The behavior of individual samples of CTD have been previously studied numerically and experimentally and it has been shown that this damper has excellent energy dissipating capacity and large ductility ratio. In this paper, application of this type of damper to steel frames is studied. Sample steel frames are constructed and equipped with CTDs and tested under cyclic loading. The results show that these dampers can serve their intended duties and dissipate considerable amount of energy. Numerical modelling of the frames confirms the experimental results and shows that by correct proportioning of the members, frame members i.e. beams, columns and braces remain elastic during lateral loading. This allows using the CTDs as a replaceable energy dissipating device. Finally CTDs are included in a reference frame and their effects on reducing seismic demand are studied using non-linear time history analysis. The results show that by using a smaller volume of steel in CTD dampers compared to traditional TADAS, the same level of response reduction may be achieved, while utilizing economic advantage of this type of damper.