(Steel-Concrete) Shear Walls,
Astaneh-Asl, Ph.D., P.E. (Principal Investigator)
Department of Civil
and Environmental Engineering
Sponsor: National Science Foundation (www.nsf.gov)
Please send your comments to A. Astaneh-Asl at email@example.com
Copyright Regents of the University of California, 2002, All rights reserved.
Cyclic Behavior and Seismic Design of
an Innovative Composite Shear Walls
A. Astaneh-Asl and Q. Zhao
University of California, Berkeley, California, USA
In this research and development project, two composite shear wall specimens were subjected to realistic cyclic loads simulating the effects of strong earthquakes. The composite shear wall specimens consisted of a steel plate shear wall welded to a moment frame and a precast reinforced concrete wall bolted to the steel plate. The concrete wall and steel plate work together as composite element. The system is shown in Figure 1. Specimen One had the innovative concept of leaving a gap between the concrete wall and the boundary columns and beams. Specimen Two had a R/C wall completely covering the surface of steel plate shear wall and bearing against the boundary beams and columns. In the second specimen, (without the gap), the R/C wall participates in the lateral load resisting system from begining of seismic event while in the Innovative system, Specimen One, the role of R/C wall initially is only to provide bracing to steel shear wall and prevent it from premature buckling. Later, when drift values reach about 2% level, the gap around the R/C wall closes and the R/C wall also participates in providing stiffness and strength to the lateral force resisting system.
The main objectives were to establish cyclic stiffness, strength, ductility, energy dissipation characteristics and failure modes for these two composite shear wall specimens. An added objective was to use the test results and to develop design-oriented information on seismic design of systems similar to the specimens tested. Of particular interest was to compare behavior of the two specimens and to verify the Response Modification Factor, Over-strength Factor, and Displacement Magnification Factor which are cuurently given in seismic design codes such as IBC-2000 for composite shear walls.
Both specimens had a total height of 20 feet-4 inches (6.2 meters) and a center to center column distance of 7 feet. Specimen One had no gap around the concrete wall while Specimen Two had a gap of about 1.5 inches between the R/C wall and boundary beams and columns. Both specimens had three stories with two full story with two ½-stories above and below the two full stories. Both specimens were subjected to the same cyclic horizontal displacement time histories by applying a cyclic horizontal force at the top of specimens. The test results were used to establish shear-force drift hysteresis loops as well as other cyclic behavior parameters. More information on the project can be found in the Steel TIPS Report on this project.
05- Astaneh-Asl, A., and Qiuhong
Zhao, (2002) "Cyclic Behavior of Steel Shear Wall Systems", Proceedings,
2002 Annual Stability Conference, Structural Stability Research Council,
April 25-27, Seattle.
04-Astaneh-Asl, A., and Qiuhong Zhao, (200o) "Seismic Studies of an Innovative and Traditional Composite Shear Walls", Proceedings, 6th ASCCS Conference on Composite and Hybrid Structures, March 22-24, 2000, Los Angeles.
03- Astaneh-Asl, A., and Zhao, Q., (2002), "Cyclic Tests of Traditional and an Innovative Composite Shear Wall-Volume I-Experimental Results", Final Report to the Sponsor, Report Number UCB/CEE-STEEL-2002/03, Dept. of Civil and Env. Engineering, Univ. of California, Berkeley, September (Currently in progress). (To purchase a copy of this publication please see above note.)
02-Astaneh-Asl, A., (2002), " Seismic Behavior and Design of Composite Steel Plate Shear Walls, Steel TIPS Report, Structural Steel Educational Council, CA, May.( A copy of this report can be downloaded free, for personal use, by clicking on the underlined title of the report.)
01- Astaneh-Asl, A., and Zhao, Q., (2002), "Cyclic Tests of Traditional and an Innovative Composite Shear Wall-Vol. II-Appendices to Final Report-Experimental Results", Final Report to the Sponsor, Report Number UCB/CEE-STEEL-2002/03a, Dept. of Civil and Env. Engineering, Univ. of California, Berkeley, September. (This publication is not in public domain.)
00. Astaneh-Asl, A., (1998), "Seismic Studies of Traditional and an Innovative Composite Shear Wall", Proposal submitted to the Sponsor: National Science Foundation. (This publication can be found at www.nsf.gov).
The research reported herein was conducted in the Department of Civil and Environmental Engineering of the University of California, Berkeley and was sponsored by the National Science Foundation. The opinions expressed here are those of the authors and do not necessarily reflect the views of the University of California, Berkeley, the Sponsors or other agencies and individuals whose names appear here.
The information presented here
has been prepared in accordance with recognized engineering principles and
is for general information only. While it is believed to be accurate, this
information should not be used or relied upon for any specific application
without competent professional examination and verification of its accuracy,
suitability, and applicability by a licensed professional engineer, designer
or architect. The publication of the material contained herein is not intended
as a representation or warranty on the part of any person or agency named
herein, that this information is suitable for any general or particular
use or of freedom from infringement of any patent or patents. Anyone making
use of this information assumes all liability arising from such use. Caution
must be exercised when relying upon specifications and codes developed by
others and incorporated by reference herein since such material may be modified
or amended from time to time subsequent to the posting of this material.
The authors bear no responsibility for such material other than to refer
to it and incorporate it by reference at the time of the initial posting
of this document.
Astaneh-Asl, A., (2002), " Seismic Behavior and Design of Composite Steel Plate Shear Walls (PDF file: 4.3MB), Steel TIPS Report, Structural Steel Educational Council, CA, May.
( A copy of this report can
be downloaded free, for personal use, by clicking on the underlined title
of the report.)
Astaneh-Asl, A., and Zhao, Q., (2002), "Cyclic Tests of Traditional and an Innovative Composite Shear Wall-Volume I-Experimental Results", Final Report to the Sponsor, Report Number UCB/CEE-STEEL-2002/03, Dept. of Civil and Env. Engineering, Univ. of California, Berkeley, September (Currently in progress).