Evaluating Equivalent Damping and Response Modification Factors of Frames Equipped by Pall Friction Dampers

Document Type : Regular Paper


1 Assistant Professor, Department of Civil Engineering, Shahid Rajai Teacher Training University, Tehran, Iran

2 M.Sc. Student, Department of Civil Engineering, Shahid Rajai Teacher Training University, Tehran, Iran

3 Department of Civil Engineering, Shahid Rajai Teacher Training University, Tehran, Iran


A study on the evaluating equivalent damping and response modification factors of frames equipped by Pall Friction Dampers is presented. To do so, buildings with various stories were considered. Nonlinear and linear dynamic time history analysis has been performed to evaluate equivalent damping for Pall Friction Dampers. Ground motions with various frequency characteristics scaled with Iranian earthquake resistant design code. In addition, nonlinear incremental dynamic analysis has been performed to evaluate the response modification factors. In this article, equivalent damping and seismic response modification factor for moment resisting frames with and without Pall Friction Dampers have been determined separately. The governing parameters were identified and their influence was traced and summarized along with implications for practical design. The results show that the equivalent damping of these frames using damper is higher than frames without it. Also we have this result for the response modification factors. It was also found that the number of stories have a great effect on these two characteristics of the buildings.


[1] Pall, A., Pall, R.T. (2004). “Performance-based design using pall friction dampers-an economical design solution”. Proceedings of the 13th World Conference on Earthquake Engineering, Vancouver, BC, Canada.
[2] Pall, A.S., Marsh, C. (1982). “Response of friction damped braced frames”. J Structure Div, ASCE, Vol. 108, pp. 1313–23.
[3] Aiken, I., Kelly, S. (1990). “Earthquake simulator testing and analytical studies of two energy absorbing systems for multi-storey structures”. Report No. UCB/EERC-90/03, EERC, Berkeley.
[4] Fitzgerald, T.F., Anagnos, T., Goodson, M., Zsutty, T. (1989). “Slotted bolted connections in a seismic design of concentrically braced connections”. Earthquake Spectra, EERI, Vol. 5, No. 2, pp. 383–91.
[5] Imad, H., Mualla, a. Borislav B. (2002). “Performance of steel frames with a new friction damper device under earthquake excitation”. Engineering Structures, Vol. 24, pp. 365–371.
[6] Grigorian, C.E., Popov, E.P., (1993). “Slotted bolted connection energy dissipaters”. Earthquake Spectra, EERI, Vol. 9, No. 3, pp. 491-504.
[7] Nims, D.K., Richter, P.J., Bachman, R.E. (1993). “The use of the energy dissipation restraint for seismic hazard mitigation”. Earthquake Spectra, EERI, Vol. 9, No. 3, pp. 467–87.
[8] Jalali, (2002). “Retrofitting of reinforced concrete structures using dampers”. Master's thesis, International Institute of Earthquake Engineering & Seismology.
[9]Kheirolahi, (2006). Therole of friction dampers on Seismic Retrofit of a 5-storey building of steel”, Master's thesis.
[10] Shariatmadar, H., Sadeghi, Z., (2008). “The evaluation of the slip load spectrum and approach on the modeling of the pall friction damper based linear and nonlinear analysis”. Proceedings of the 4th Civil Engineering National Conference, Tehran, Iran.
[11] Abedini, Sh. (2010)., “Parametric evaluation of the seismic behavior of the energy dissipation mechanism in dampers equipped structures”, Master's thesis.
[12] Asgarian, B., Shokrgozar, H.R. (2009). “BRBF Response modification factor”. Journal of Construction Steel Research, Vol. 65, No. 2, pp. 290-298.
[13] Mahmoudi, Abdi, (2011). “Evaluating response modification factors of TADAS frames”.
[14] BHRC, (2005). “Iranian code of particle for seismic resistance design of buildings”. Standard No. 2800 (3rd edition), Building and Housing Research Center, Tehran, Iran.
[15] MHUD, (2006). “Iranian national building code, part 10, steel structure design”. Ministry of Housing and Urban Development, Tehran, Iran.
[16] Mazzolani, F.M., Piluso, V. (1996). “Theory and design of seismic resistant steel frames”. Spon, London.
[17] Fajfar, P. (2002). “Structural analysis in earthquake engineering- a breakthough of simplified nonlinear methods”. Proceedings of the 12th European conference on earthquake engineering, Barbican Centre, London, UK.
[18] Mahmoudi, M., Zaree, M. (2010). “Evaluating response modification factors of concentrically braced steel frames”. Journal of Constructional Steel Research, Vol. 66, No. 10, pp. 1196-1204.
[19] Mahmoudi, M. (2003). “The relationship between over-strength and members ductility of RC moment resisting frames”. Proceedings of the 7th Pacific Conference on Earthquake Engineering, University of Canterbury, Christchurch.
[20] Schmidt, B.J., Bartlett, F.M. (2002). “Review of resistance factor for steel: Resistance distribution and resistance factor calibration”. Canadian Journal of Civil Engineering, Vol. 29, pp. 109-18.
[21] FEMA-356, (2000). “Pre-standard and commentary for the seismic rehabilitation of building”. Federal Emergency Management Agency, Washington DC.
[22] Filiatrault, A., Cherry, S. (1986). “Seismic tests of friction-damped steel frames”. Proceedings of the Third Conference on Dynamic Response of Structures, ASCE, Los Angeles, USA.
[23] Kelly, J.M., Aiken, I.D., Pall, A.S. (1988). “Seismic response of a nine-story steel frame with friction-damped cross-bracing”. Report No. UCB / EERC, 88/17, Earthquake Engineering Research Center, University of California at Berkeley, pp. 1-7.
[24] Constantinou, M.C., Reinhorn, A.M., Mokha, A.S., Watson, R. (1991). “Displacement control device for base isolated bridges”. Earthquake Spectra, EERI, Vol. 7, No. 2, pp. 179–200.