Behavior of Retrofitted URM Walls under Simulated Earthquake Loading
Publication: Journal of Composites for Construction
Volume 3, Issue 3
Abstract
Unreinforced masonry (URM) buildings perform poorly under seismic forces and have been identified as the main cause of loss of life in recent earthquakes. Many of these structures fail in out-of-plane bending due to the lack of reinforcement. In this study, the experimental results from three half-scale unreinforced brick walls retrofitted with vertical composite strips are presented. The specimens were subjected to cyclic out-of-plane loading. Five reinforcement ratios and two different glass fabric composite densities were investigated. The mode of failure is controlled by tensile failure when wider and lighter composite fabrics are used and by delamination when stronger ones are used. The tested specimens were capable of supporting a lateral load up to 32 times the weight of the wall. A deflection as much as 2% of the wall height was measured. Although both URM walls and composite strips behave in a brittle manner, the combination resulted in a system capable of dissipating some energy. Retrofitting URM walls with composite strips proved to be a good and reliable strengthening alternative.
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References
1.
Abboud, B. E., Hamid, A. A., and Harris, H. G. (1990). “Small-scale modeling of concrete block masonry structures.” ACI Struct. J., 87(2).
2.
Abrams, D. P., Angel, R., and Uzanski, J. (1993). “Transverse strength of damaged URM infills.” Proc., ASCE Struct. Congr., ASCE, Reston, Va.
3.
Abrams, D. P., and Costley, A. C. (1996). “Seismic evaluation of unreinforced masonry buildings.” 11th World Conf. on Earthquake Engrg., Paper No. 976.
4.
Bennedetti, D., and Benzoni, G. M. (1984). “A numerical model for seismic analysis of masonry buildings: Experiments and correlations.” Earthquake Engrg. & Struct. Dyn., 12.
5.
Bhende, D., and Ovadia, D. (1994). “Out-of-plane strengthening scheme for reinforced masonry walls.” Concrete Int., April, 30–34.
6.
Bruneau, M. (1994). “Seismic evaluation of unreinforced masonry buildings: A state-of-the-art report.” Can J. Civ. Engrg., Ottawa, 21, 512–539.
7.
Dawe, J. L., and Seah, C. K. (1989). “Out-of-plane of concrete masonry infilled panels.” Can J. Civ. Engrg., Ottawa, 16, 854–864.
8.
Deppe, K. (1988). “The Whittier Narrows, California earthquake of October 1, 1987—Evaluation of strengthened unreinforced masonry in Los Angeles City.” Earthquake Spectra 4(1), 157–179.
9.
Drysdale, R. D., Hamid, A. A., and Bake, R. L. (1994). Masonry structures behavior and design. Prentice-Hall, Englewood Cliffs, N.J.
10.
Ehsani, M. R., and Saadatmanesh, H. (1994). “Out-of-plane strength of unreinforced brickwork retrofitted with fiber composites.” Proc., NCEER Workshop on Seismic Response of Masonry Infills, National Center for Earthquake Engineering Research, State University of New York at Buffalo.
11.
Ehsani, M. R., and Saadatmanesh, H. (1996). “Seismic retrofitting of URM walls with fiber composites.” Masonry Soc. J., 14(2), 63–72.
12.
Ehsani, M. R., and Saadatmanesh, H. (1997). “Fiber composites: An economical alternative for retrofitting earthquake-damaged precast-concrete walls.” Earthquake Spectra, 13(2), 225–241.
13.
Essaway, A. M. ( 1986). “Strength of hallow Concrete block masonry walls subjected to lateral (out-of-plane) loading,” PhD thesis, McMaster University, Canada.
14.
Expected seismic performance of buildings. (1994). Earthquake Engineering Research Institute Ad Hoc Committee on Seismic Performance, El Cerrito, Calif.
15.
Flanagan, R. D., Bennett, R. M., and Beavers, J. E. (1993). “Seismic behavior of unreinforced hallow clay tile infilled frames.” Masonry design and construction problems and repair, ASTM STP 1180, ASTM, West Conshohoken, Pa.
16.
Hamid, A. A., Chia-Calabria, C., and Harris, G. H. (1992). “Flexural behavior of joint reinforced block masonry walls.” ACI Struct. J., 89(1), 20–26.
17.
Handbook for seismic rehabilitation of existing buildings. (1992). FEMA-127, Federal Emergency Management Agency, Washington, D.C.
18.
Hendry, A. W. (1973). “The lateral strength of unreinforced brickwork.” Struct. Engrg. J., 51, 42–50.
19.
Kehoe, B. E. (1996). “Performance of retrofitted unreinforced masonry buildings.” 11th World Conf. on Earthquake Engrg., Paper No. 1417.
20.
Laursen, P. T., Seible, F., Hegemier, G. A., and Innamorato, D. ( 1995). “Seismic retrofit and repair of masonry walls with carbon overlays.” Non-metallic (FRP) reinforcement for concrete structures. Reunion Internationale des Laboratoires d'Essais et de Recherches sur les Materiaux et les Constructions.
21.
Lester, J. (1998). “Staking your claim.” Civ. Engrg., ASCE, July, 65–67.
22.
Lizundia, B., Holmes, W. T., Longstreth, M., and Kren, A. (1997). “Development of procedures to enhance the performance of rehabilitated URM buildings.” NIST GCR 97-724-1, National Institute of Standards and Technology, Building and Fire Research Laboratory, Gaithersburg, Md.
23.
“Methodology for mitigation of seismic hazard in existing unreinforced masonry buildings: Wall testing out-of-plane.” (1981). ABK-TR-04. El Segundo, Calif.
24.
Schwegler, G. (1995). “Masonry construction strengthened with fiber composites in seismically endangered zones.” 10th Eur. Conf. on Earthquake Engrg., 2299–2303.
25.
Schwegler, G., and Kelterborn, P. (1996). “Earthquake resistance of masonry structures strengthened with fiber composites.” 11th World Conf. on Earthquake Engrg., Paper No. 1460.
26.
Siegel, H. I., and Fowler, L. W. (1994). “Jackson Brewery: Upgrading historic unreinforced brick buildings.” Earthquake Spectra, 10(1).
27.
Sucuoglu, H., and McNiven, H. D. (1991). “Seismic shear capacity of reinforced masonry piers.”J. Struct. Engrg., ASCE 117(7), 2166–2186.
28.
Tobriner, S. M. (1984). “At earthquakes: 1755–1907.” Earthquake Spectra, 1(1), 125–149.
29.
Tomazevic, M. (1996). “Recent advances in earthquake-resistant design of masonry buildings: European prospective.” 11th World Conf. on Earthquake Engrg., Paper No. 2012.
30.
Uniform code for building conservation. (1994). International Conference of Building Officials, Whittier, Calif.
31.
Velazquez-Dimas, J. I. ( 1998). “Out-of-plane cyclic behavior of URM walls retrofitted with fiber composites,” PhD dissertation, Department of Civil Engineering and Engineering Mechanics, University of Arizona, Tucson.
32.
Velazquez-Dimas, J. I., Ehsani, M. R., and Saadatmanesh, H. (1999). “Out-of-plane behavior of brick masonry walls strengthened with fiber composites.” Earthquake Spectra, in press.
33.
Weeks, J., Seible, F., Hegemier, G., and Pristley, M. J. N. (1994). “The U.S.-TCCMAR full-scale five-story masonry research building test.” University of California, San Diego.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 3 • Issue 3 • August 1999
Pages: 134 - 142
History
Received: Jan 26, 1998
Published online: Aug 1, 1999
Published in print: Aug 1999
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