Unreinforced Concrete Masonry Walls Strengthened with CFRP Sheets and Strips under Pendulum Impact
Publication: Journal of Composites for Construction
Volume 14, Issue 6
Abstract
Impact tests using drop-weight pendulum on nine 1.2-m-high full-scale concrete masonry block walls were conducted to investigate the out-of-plane impact behavior of unreinforced masonry (URM) walls externally strengthened with carbon-fiber-reinforced polymer (CFRP) composites. Three strengthening schemes on one side of the wall were studied: continuous unidirectional and continuous woven sheets, discrete strips in a vertical pattern, and discrete strips in orthogonal and diagonal patterns. All walls were vertically positioned resting on a knife-edge support with one face leaning against two steel rollers close to the upper and lower edges of the wall. The impact load was applied at the wall center through a drop-weight pendulum impact tester with various drop heights. Test results revealed that using composite laminates or strips could significantly improve the impact performance of URM walls. The wall strengthened with continuous woven sheets performed better than the one with unidirectional sheet. With the same amount of fiber-reinforced polymer strip material, the wall with narrower but more closely spaced strips performed slightly better than the one with wider strips.
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Acknowledgments
The writers would like to thank the technicians and undergraduate and graduate student researchers for their assistance on this project at the University of California, Davis. The FRP products are from Hexcel Reinforcements Corp., provided by their local supplier in Northern California.
References
Abrate, S. (1998). Impact on composite structures, Cambridge University Press, Cambridge, Mass.
Al-Charr, G. H., and Hasan, H. A. (2002). “Dynamic response and seismic testing of CMU walls rehabilitated with composite material applied to only one side.” Structures and Buildings, 152(2), 135–146.
Albert, M. L., Elwi, A. E., and Cheng, J. J. R. (2001). “Strengthening of unreinforced masonry walls using FRPs.” J. Compos. Constr., 5(2), 76–84.
Al-Salloum, Y. A., and Almusallam, T. H. (2005). “Load capacity of concrete masonry block walls strengthened with epoxy-bonded GFRP sheets.” J. Compos. Mater., 39(19), 1719–1729.
American Concrete Institute (ACI). (2009). “Guide for the design and construction of externally bonded fiber-reinforced polymer systems for strengthening unreinforced masonry structures.” ACI 440-XR, Detroit.
ASTM. (2005a). “Standard test method for compressive strength of masonry prisms.” ASTM C1314-03b, West Conshohocken, Pa.
ASTM. (2005b). “Standard test method for sampling and testing grout.” ASTM C1019-03, West Conshohocken, Pa.
Carney, P., and Myers, J. J. (2005). “Out-of-plane static and blast resistance of unreinforced masonry wall connections strengthened with FRP.” ACI Special Publication No. SP-230-14, Farmington Hills, Mich, 229–248.
Davidson, J. S., Fisher, J. W., Hammons, M. I., Porter, J. R., and Dinan, R. J. (2005). “Failure mechanisms of polymer-reinforced concrete masonry walls subjected to blast.” J. Struct. Eng., 131(8), 1194–1205.
Dennis, S. T., Baylot, J. T., and Woodson, S. C. (2002). “Response of 1/4-scale concrete masonry unit (CMU) walls to blast.” J. Eng. Mech., 128(2), 134–142.
Ehsani, M. R., Saadatmanesh, H., and Velazquez-Dimas, J. I. (1999). “Behavior of retrofitted URM walls under simulated earthquake loading.” J. Compos. Constr., 3(3), 134–142.
Erki, M. A., and Meier, U. (1999). “Impact loading of concrete beams externally strengthened with CFRP laminates.” J. Compos. Constr., 3(3), 117–124.
Galati, N., Garbin, E., Tumialan, J. G., and Nanni, A. (2005). “Design guidelines for masonry structures: Out of plane loads.” ACI Special Publication No. SP-230-16, Farmington Hills, Mich., 269–288.
Gilbert, M., Hobbs, B., and Molyneaux, T. C. K. (2002). “The performance of unreinforced masonry walls subjected to low-velocity impacts: Experiments.” Int. J. Impact Eng., 27(3), 231–251.
Hamed, E., and Rabinovitch, O. (2005). “Dynamic behavior of reinforced concrete beams strengthened with composite materials.” J. Compos. Constr., 9(5), 429–440.
Hamed, E., and Rabinovitch, O. (2008). “Nonlinear dynamic behavior of unreinforced masonry walls subjected to out-of-plane loads.” J. Struct. Eng., 134(11), 1743–1753.
Hamilton, H. R., III, and Dolan, C. W. (2001). “Flexural capacity of glass FRP strengthened concrete masonry walls.” J. Compos. Constr., 5(3), 170–178.
Hamoush, S., McGinley, M., Mlakar, P., Scott, D., and Murray, K. (2001). “Out-of-plane strengthening of masonry walls with reinforced composites.” J. Compos. Constr., 5(3), 139–145.
Korany, Y., and Drysdale, R. (2006). “Rehabilitation of masonry walls using unobtrusive FRP techniques for enhanced out-of-plane seismic resistance.” J. Compos. Constr., 10(3), 213–222.
Kuzik, M. D., Elwi, A. E., and Cheng, J. J. R. (2003). “Cyclic flexure tests of masonry walls reinforced with glass fiber reinforced polymer sheets.” J. Compos. Constr., 7(1), 20–181.
Panarese, W. C., Kosmatka, S. H., and Randall, F. A., Jr. (1991). Concrete masonry handbook: For architects, engineers, builders, 5th Ed., Portland Cement Association, Skokie, Ill.
Schmidt, M. E., and Cheng, L. (2009). “Impact response of externally strengthened unreinforced masonry walls using CFRP.” J. Compos. Constr., 13(4), 252–261.
Sun, C. T., and Yang, S. H. (1980). “Contact law and impact response of laminated composites.” NASACR-159884, Purdue University, West Lafayette, Ind.
Tan, K. H., and Patoary, M. K. H. (2004). “Strengthening of masonry walls against out-of-plane loads using fiber-reinforced polymer reinforcement.” J. Compos. Constr., 8(1), 79–87.
Tang, T., and Saadatmanesh, H. (2005). “Analytical and experimental studies of fiber-reinforced polymer strengthened concrete beams under impact loading.” ACI Struct. J., 102(1), 139–149.
Triantafillou, T. C. (1998). “Strengthening of masonry structures using epoxy-bonded FRP laminates.” J. Compos. Constr., 2(2), 96–104.
Tumialan, J. G., Galati, N., and Nanni, A. (2003). “Fiber-reinforced polymer strengthening of unreinforced masonry walls subject to out-of-plane loads.” ACI Struct. J., 100(3), 321–329.
Velazquez-Dimas, J. I., and Ehsani, M. R. (2000). “Modeling out-of-plane behavior of URM walls retrofitted with fiber composites.” J. Compos. Constr., 4(4), 172–181.
Information & Authors
Information
Published In
Journal of Composites for Construction
Volume 14 • Issue 6 • December 2010
Pages: 775 - 783
Copyright
© 2010 ASCE.
History
Received: Aug 19, 2009
Accepted: Apr 14, 2010
Published online: Apr 16, 2010
Published in print: Dec 2010
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