Abstract
This paper deals with effect of friction dampers on seismic response of 2D steel frames in comparison with structures stiffened by large sections and centrally braced. For the present study three structures with six storeys are subjected to a time history analysis. To study the effect of dampers in structures in comparison with structures stiffened by large sections and centrally braced, are analysed the relative level displacements, maximum displacement on the top, variation of lateral acceleration at the last level and variation of the maximum seismic base shear force depending on the lateral rigidity. The results indicate that placement of friction dampers improve the response of structures in all analyzed terms.