Advanced Steel Construction

Vol. 7, No. 2, pp. 192-205 (2011)


EFFECT OF DAMPERS ON SEISMIC DEMAND OF SHORT PERIOD STRUCTURES IN DEEP COHESIONLESS SITES

 

N.S. Armouti

Associate Professor of Civil Engineering

University of Jordan, Amman 11942, Jordan

(Corresponding author: E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.)

Received: 18 October 2010; Revised: 26 December 2010; Accepted: 3 January 2011

 

DOI:10.18057/IJASC.2011.7.2.6

 

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ABSTRACT

Seismic behavior of short period structures with dampers founded on deep cohesionless soil is investigated. A Single bay frame with diagonal damper that represents short period structures is evaluated in response to the excitation of a set of earthquake records. The frame system is modeled as a Generalized Single Degree of Freedom System, and is subjected to five earthquake records representative of deep cohesionless site conditions. The relationship between the force modification factor and the global ductility demand for short period structures founded on deep cohesionless soil, in the presence of dampers, tends to approach those of long period ones. Compared with seismic demand under general site conditions, short period structures founded on deep cohesionless soil show less seismic demand and lower sensitivity to earthquake excitations. Similar to seismic demand in general site conditions, and except for period of 0.1 second, short period structures in deep cohesionless sites with dampers having damping ratios higher than 20% tend to keep the structural response in the elastic range even for high values of force reductions. Seismic code provisions should be revised to account for short period effect under seismic excitation.

 

KEYWORDS

Ductility demand, seismic demand, short period, dampers, deep cohesionless soil


REFERENCES

[1]       IBC., “International Building Code”, International Code Council, Washington, DC. 2006

[2]       Nassar, A. A. and Krawinkler H., “Seismic Demands for SDOF and MDOF systems”, The John A. Blume Earthquake Engineering Center, Stanford University, California, 1991, Report No. 95.

[3]       Armouti, N.S., “Response of Structures to Synthetic Earthquakes”, Proceeding of the 9th Arab Structural Engineering Conference, Abu Dhabi, UAE, 2003, Vol. 1, pp. 331-339.

[4]       Nagarajaiah, S. and Narasimhan, S., “Seismic Control of Smart Base Isolated Buildings with New Semiactive Variable Damper”, Earthquake Engineering and Structural Dynamics, 2007, Vol. 36, No. 6, pp. 729-749.

[5]       Madhekar, S. and Jangid, R., “Variable Dampers for Earthquake Protection of Benchmark Highway Bridges”, Smart Materials and Structures, 2009, Vol. 18, No. 11, pp. 115011, No. 18.

[6]       Malhorta, A., Carson, D., Gopal, P., Braimah, A., Giovanni, G. and Pall, R., “Friction Dampers for Seismic Upgrade of St. Vincent Hospital, Ottawa”, Proceeding of the 13th World Conference on Earthquake Engineering, Vancouver, B.C., Canada, 2004, Paper No. 1952.

[7]       Potty, N. and Nambissan, S., “Seismic Retrofit of Elevated Steel Water Tanks”, Proceeding of the International Conference on Construction and Building Technology, Kuala Lumpur, Malaysia, 2008, pp. 99-108.

[8]       Chandra, R., Masand, M., Nandi, S., Tripathi, C., Pall, R. and Pall, A., “Friction-dampers for Seismic Control of La Gardenia Towers South City, Gurgaon, India”, Proceeding of the 12th World Conference on Earthquake Engineering, Auckland, New Zealand, 2000, Paper 2008.

[9]       Raju, K., Prasad, A., Lakshmanan, N., Muthumani, K., Jagadish, D. and Amuthasheela, R., “Optimum Distribution of Viscous Fluid Dampers in Structural Systems”, Journal of The Institution of Engineers (India), 2005, Vol. 86, pp. 103-108.

[10]     Takewaki, I., Katsura, K. and Ku, N., “Earthquake Input Energy to Two Buildings Connected by Viscous Dampers”, Journal of Structural Engineering, ASCE, 2007, Vol. 133, No, 5, pp. 620-628.

[11]     Miyamoto, H.K, Gilani, A.S.J., Wada, A. and Ariyaratana, C., “Limit States and Failure Mechanisms of Viscous Dampers and the Implications for Large Earthquakes”, Earthquake Engineering and Structural Dynamics, 2010, Vol. 39, No. 11, pp. 1279-1297.

[12]     Armouti, N.S., “Effect of Dampers on Seismic Demand of Short Period Structures”, Jordan Journal of Civil Engineering, 2010, Vol. 4, No. 4, pp. 367-377.

[13]     Clough, R.W. and Penzien, J., “Dynamics of Structures”, 2nd Ed., McGraw Hill, New York, 1993.

[14]     CSI, “Structural Analysis Program, SAP2000 Nonlinear Version 12”, Computers and Structures, Inc., Berkeley, California, 2008.