EFFECTS OF ADAS DAMPERS ON PLASTIC HINGE ROTATION OF DUAL STEEL FRAMES SUBJECTED TO NEAR-FIELD AND FAR-FIELD EARTHQUAKES

In this investigation, the effects of Added Damping and Stiffness (ADAS) yielding dampers on plastic hinge rotation of dual seismic-resistance steel frame subjected to far-field and near-field earthquakes are discussed. ADAS dampers increase energy absorption capacity of structures against earthquakes. A weak moment frame is considered to study the effects of these dampers. Then, two approaches are employed to strengthen the frame: either by concentrically inverted V braces (Chevron) or the same bracing but equipped with ADAS dampers. This two-dimensional frame is 8 stories high with three spans. The seismic loading and structural steel design codes used in this research are Iranian Standard 2800 and Topic 10, respectively. The first component of FEMA P-695 accelerograms, including four far-field and three near-field records, were considered for this study. The nonlinear Time History analyses carried out by using a finite element method program, OpenSees. The results showed that using ADAS dampers in concentrically braced frames reduces the base shear and beam plastic hinge rotations. Additionally, these dampers reduce the stiffness of frame as well.

Keywords:

Structural Control , ADAS Dampers , Plastic Hinge Rotation , Energy Dissipation , Dual Steel Frame