Behavioral factor of Pall and Rotational dampers under far field and near field records

Nowadays, in order to reduce the damages of structures during earthquakes, the method of reducing earthquake forces with control tools is used. In this study, the effect of two types of Pall and Rotational frictional dampers in the same bracing frames on behavior factor to minimize the design force has been analyzed. The structures were first modeled and the designed sections for beam, column and bracing were taken and then nonlinear time history analysis for seven near field earthquakes and eight far field earthquakes has been used and it has been compared with nonlinear static analysis. In this study, a total of 9 nonlinear static analyses and 135 dynamic analysis of time history have been used. This behavior factor was 5.0 for the structure equipped with Pall damper and 4.5 for the structure equipped with Rotational damper. This indicates 42% increase in behavior factor for structures equipped with Pall damper and 28% increase in this coefficient for structures equipped with Rotational damper, which leads to less seismic responses, more resistant in structure and ultimately more economical design. The results also show an increase in behavior factor in lower height structures than high-rise structures.On the other hand, the results show an increase in behavior factor by 12% and 5% in Pall damper and Rotational structures under near field earthquakes compared to the far field. The behaviour factor for structure equipped with Pall damper subjected to near and far acceleration time history is equal to 5 and 4.5, respectively. This factor is calculated to be 4.5 and 4.25 for Rotational damper for near and far records, correspondingly. As a result, the use of Pall dampers in areas close to active faults is suggested.