Evaluation of NSP to Estimate Seismic Deformation: SDF Systems
Publication: Journal of Structural Engineering
Volume 126, Issue 4
Abstract
Investigated in this paper is the approximation in the ATC-40 nonlinear static procedure (NSP) that the earthquake-induced deformation of an inelastic single-degree-of-freedom (SDF) system can be estimated by an iterative method requiring analysis of a sequence of equivalent linear systems. Several deficiencies in the ATC-40 Procedure A are demonstrated. This iterative procedure did not converge for some of the systems analyzed. It converged in many cases, but to a deformation much different than dynamic (nonlinear response history or inelastic design spectrum) analysis of the inelastic system. The ATC-40 Procedure B always gives a unique value of deformation, same as that determined by Procedure A if it converged. These approximate procedures underestimate significantly the deformation for a wide range of periods and ductility factors with errors approaching 50%, implying that the estimated deformation is about half the “exact” value. Surprisingly, the ATC-40 procedures are deficient relative to even the elastic design spectrum in the velocity-sensitive and displacement-sensitive regions of the spectrum. For systems with a period in these regions, the peak deformation of an inelastic system can be estimated from the elastic design spectrum using the well-known equal displacement rule. However, the approximate procedure requires analyses of several equivalent linear systems and still produces worse results.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
ATC. (1996). “Seismic evaluation and retrofit of concrete buildings.” Rep. ATC-40, Applied Technology Council, Redwood City, Calif.
2.
Chopra, A. K. (1995). Dynamics of structures: Theory and applications to earthquake engineering. Prentice-Hall, N.J.
3.
Chopra, A. K., and Goel, R. K. (1999). “Capacity-demand-diagram methods for estimating seismic deformation of inelastic structures: SDF systems.” Rep. No. PEER-1999/02, Pacific Earthquake Engrg. Res. Ctr., University of California, Berkeley, Calif.
4.
Deierlein, G. G., and Hsieh, S.-H. (1990). “Seismic response of steel frames with semi-rigid connections using the capacity spectrum method.” Proc., 4th U.S. Nat. Conf. on Earthquake Engrg., Vol. 2, 863–872.
5.
FEMA. (1997). “NEHRP commentary on the guidelines for the seismic rehabilitation of buildings.” FEMA-274, Federal Emergency Management Agency, Washington, D.C.
6.
Freeman, S. A. ( 1978). “Prediction of response of concrete buildings to severe earthquake motion.” Publ. SP-55, American Concrete Institute, Detroit, 589–605.
7.
Freeman, S. A., Nicoletti, J. P., and Tyrell, J. V. (1975). “Evaluations of existing buildings for seismic risk—A case study of Puget Sound Naval Shipyard, Bremerton, Washington.” Proc., 1st U.S. Nat. Conf. on Earthquake Engrg., 113–122.
8.
Hudson, D. E. (1965). “Equivalent viscous friction for hysteretic systems with earthquake-like excitations.” Proc., 3rd World Conf. on Earthquake Engrg., Vol. II, 185–202.
9.
Iwan, W. D., and Gates, N. C. (1979). “Estimating earthquake response of simple hysteretic structures.”J. Engrg. Mech. Div., ASCE, 105(3), 391–405.
10.
Jennings, P. C. (1968). “Equivalent viscous damping for yielding structures.”J. Engrg. Mech. Div., ASCE, 94(1), 103–116.
11.
Krawinkler, H. K., and Nassar, A. A. ( 1992). “Seismic design based on ductility and cumulative damage demands and capacities.” Nonlinear seismic analysis and design of reinforced concrete buildings, P. Fajfar and H. Krawinkler, eds., Elsevier Science, New York.
12.
Newmark, N. M., and Hall, W. J. ( 1982). Earthquake spectra and design. Earthquake Engineering Research Institute, Berkeley, Calif.
13.
Paret, T. F., Sasaki, K. K., Eilbekc, D. H., and Freeman, S. A. ( 1996). “Approximate inelastic procedures to identify failure mechanisms from higher mode effects.” 11th World Conf. on Earthquake Engrg.
14.
Reinhorn, A. M., Li, C., and Constantinou, M. C. (1995). “Experimental and analytical investigations of seismic retrofit of structures with supplemental damping.” Rep. No. NCEER-95-0001, State University of New York at Buffalo, Buffalo, N.Y.
15.
Veletsos, A. S., and Newmark, N. M. (1960). “Effects of inelastic behavior on the response of simple system to earthquake motions.” Proc., 2nd World Conf. on Earthquake Engrg., Vol. 2, 895–912.
16.
Vidic, T., Fajfar, P., and Fischinger, M. (1994). “Consistent inelastic design spectra: Strength and displacement.” Earthquake Engrg. and Struct. Dyn., 23(5), 507–521.
Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 126 • Issue 4 • April 2000
Pages: 482 - 490
History
Received: Apr 21, 1999
Published online: Apr 1, 2000
Published in print: Apr 2000
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.