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Single and Multiple Tuned Liquid Column Dampers for Seismic Applications.


pdf icon Single and Multiple Tuned Liquid Column Dampers for Seismic Applications. (1727 K)
Sadek, F.; Mohraz, B.; Lew, H. S.

NISTIR 5920; 45 p. November 1996.

Earthquake Engineering and Structural Dynamics, Vol. 27, No. 5, 439-463, 1998.

Available from:

National Technical Information Service (NTIS), Technology Administration, U.S. Department of Commerce, Springfield, VA 22161.
Telephone: 1-800-553-6847 or 703-605-6000;
Fax: 703-605-6900.
Website: http://www.ntis.gov
Order number: PB97-132062

Keywords:

dampers; seismic loads; earthquakes; statistical analysis

Abstract:

The optimum parameters of single and multiple tuned liquid column dampers (TLCD) for reducing the response of structures to seismic loads are presented. A deterministic analysis is carried out using 72 earthquake ground motion records to determine the optimum tuning ratio, tube width to liquid length ratio, and head loss coefficient corresponding to a given mass ratio for single tuned liquid column dampers (STLCD). A similar analysis is performed to determine the optimum central tuning ratio, tuning bandwidth, and grouping of dampers for multiple tuned liquid column dampers (MTLCD). The optimum parameters are used to compute the response of several single-degree-of-freedom structures and one multi-degree-of-freedom structure with single and multiple TLCDs to different earthquake excitations. The study indicated that: (a) the use of the optimum parameters reduces the displacement and acceleration responses; (b) MTLCDs have a slight advantage over STLCDs in reducing the response; and (c) MTLCDs are robust to errors in estimating the structural parameters. The solution from an analysis using TLCDs is compared with that using tuned mass dampers where it is found that both devices result in comparable reductions in the response. Design examples using STLCDs and MTLCDs in a simple bridge model and in a ten-story structure are presented to illustrate how the parameters are selected and demonstrate the performance of the devices under different ground excitations.