Experimental Evaluation of Cyclically Loaded Reduced Beam Section Moment Connections
Publication: Journal of Structural Engineering
Volume 128, Issue 4
Abstract
This paper describes an experimental study on radius cut reduced beam section (RBS) moment connections for use in seismic resistant steel moment frames. The effects of panel zone strength, composite behavior with a concrete slab, and the beam web-to-column flange connection were specifically addressed in these tests. In total, eight double-sided specimens were designed, fabricated, and tested in this study, providing data for sixteen individual RBS connections. Each specimen was subjected to a standard quasi-static cyclic load pattern. Overall, the specimens performed well with seven of the eight achieving total (elastic plus plastic) story drift ratios of at least 0.04 radians in magnitude before experiencing 20% strength degradation. The other test was stopped due to out-of-plane instability after being loaded to 0.03 radians of total story drift. Comparison of the response of specimens with strong panel zones, balanced panel zones, and weak panel zones relative to beam strength led to the conclusion that weak panel zones allow for the most stable hysteretic response at large drift levels. Inclusion of a composite slab in these tests appeared to stabilize the beams against lateral torsional buckling with no consistently detectable increase in the strains in the bottom beam flange. Welding the beam web to the column flange seemed to decrease the likelihood of weld fracture in these specimens.
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References
AISC. (1994). Proc., AISC Special Task Committee on the Northridge Earthquake, Los Angeles, March 14–15, 1994, American Institute of Steel Construction, Inc., Chicago.
AISC. (1997). Seismic provisions for structural steel buildings, American Institute of Steel Construction, Chicago.
ASTM. (1994).
Bertero, V. V., Anderson, J. C., and Krawinkler, H. (1994). “Performance of steel building structures during the Northridge earthquake.” Rep. No. UCB/EERC - 94/09, Earthquake Engineering Research Center, Univ. of California at Berkeley, Berkeley, Calif.
Chen, S. J., Yeh, C. H., and Chu, J. M.(1996). “Ductile steel beam-to-column connections for seismic resistance.” J. Struct. Eng., 122(11), 1292–1299.
Chi, W.-M., Deierlein, G. G., and Ingraffea, A. R.(2000). “Fracture toughness demands in welded beam-column moment connections.” J. Struct. Eng., 126(1), 88–97.
Choi, J., Stojadinovic, B., and Goel, S. C. (2000). “Parametric tests on the free flange connections.” SAC/BD-00/02, SAC Joint Venture, Sacramento, Calif.
Clark, P. (1997). “Protocol for fabrication, inspection, testing, and documentation of beam-column connection tests and other experimental specimens.” Background Document No. 97/02, SAC Joint Venture, Sacramento, Calif.
El-Tawil, S., Mikesell, T., Vidarsson, E., and Kunnath, S. (1998). “Strength and ductility of FR welded-bolted connections.” Background Document No. 98/01, SAC Joint Venture, Sacramento, Calif.
Engelhardt, M. D. (1999). “The 1999 T. R. Higgins Lecture: Design of reduced beam section moment connections.” Proc., 1999 North American Steel Construction Conf., American Institute of Steel Construction, Toronto, January 1–29, 1999.
Engelhardt, M. D., Winneberger, T., Zekany, A. J., and Potyraj, T. J.(1998). “Experimental investigation of dogbone moment connections.” Eng. J., 35(4), 128–139.
Engelhardt, M. D., Fry, G. T., Jones, S., Venti, M., and Holliday, S. (2000). “Behavior and design of radius cut, reduced beam section connections.” SAC/BD-00/17, SAC Joint Venture, Sacramento, Calif.
FEMA (2000). “Recommended seismic design criteria for new steel moment-frame buildings.” FEMA-350, Federal Emergency Management Agency 〈http://www.fema.gov/library/fema350.htm〉.
Frank, K. H., Barsom, J. M., and Hamburger, R. O. (2000). “State of the Art Report on Base Metals and Fracture.” Rep. No. FEMA-355A, Federal Emergency Management Agency, Washington, D.C.
Gilton, C., Chi, B., and Uang, C. M. (2000a). “Cyclic testing of a free flange moment connection.” SAC/BD-00/19, SAC Joint Venture, Sacramento, Calif.
Gilton, C., Chi, B., and Uang, C. M. (2000b). “Cyclic response of RBS moment connections: weak axis configuration and deep column effects.” SAC/BD-00/23, SAC Joint Venture, Sacramento, Calif.
Goel, S. C., Stojadinovic, B., and Lee, K.-H.(1997). “Truss analogy for steel moment connections.” Eng. J., 37(2), 43–53.
Hajjar, J. F., Leon, R. T., Gustafson, M. A., and Shield, C. K.(1998). “Seismic response of composite moment-resisting connections. II: Behavior.” J. Struct. Eng., 124(8), 877–885.
Iwankiw, N. R., and Carter, C.(1996). “The dogbone: a new idea to chew on.” Modern Steel Constr., 36(4), 18–23.
Jones, S. L., and Fry, G. T. (2000). “Tests of reduced beam section connections with composite floor diaphragms.” Composite and Hybrid Structures: Proc., 6th ASCCS Int. Conf. on Steel-Concrete Composite Structures, ASCCS-6 Secretariat, Dept. of Civil Engineering, Univ. of Southern California, Los Angeles, Vol. 2, 713–719.
Kim, T., Whittaker, A. S., Bertero, V. V., and Gilani, A. S. J. (2000). “Steel moment resisting connections reinforced with cover and flange plates.” SAC/BD-00/27, SAC Joint Venture, Sacramento, Calif.
Krawinkler, H., Bertero, V. V., and Popov, E. P. (1971). “Inelastic behavior of steel beam-to-column subassemblages.” Rep. No. UCB/EERC-71/07, Earthquake Engineering Research Center, Univ. of California at Berkeley, Berkeley, Calif.
Lee, K.-H., Stojadinovic, B., Goel, S. C., Margarian, A. G., Choi, J., Wongkaew, A., Reyher, B. P., and Lee, D.-Y. (2000). “Parametric tests on unreinforced connections.” SAC/BD-00/01, SAC Joint Venture, Sacramento, Calif.
Leon, R. T., Hajjar, J. F., and Gustafson, M. A.(1998). “Seismic response of composite moment-resisting connections. I: Performance.” J. Struct. Eng., 124(8), 868–876.
Plumier, A.(1997). “The dogbone: back to the future.” Eng. J., 34(2), 61–67.
Popov, E. P., Yang, T. S., and Chang, S. P.(1998). “Design of steel MRF connections before and after the 1994 Northridge Earthquake.” Eng. Struct., 20(12), 1030–1038.
Ricles, J. M., Mao, C., Lu, L. W., and Fisher, J. (2000). “Development and evaluation of improved details for ductile welded unreinforced flange connections.” SAC/BD-00/24, SAC Joint Venture, Sacramento, Calif.
Suita, K., Tamura, T., Morita, S., Nakashima, M., and Engelhardt, M. D.(1999). “Plastic rotation capacity of steel beam-to-column connections using a reduced beam section and no weld access hole design—full scale tests for improved steel beam-to-column subassemblies—Part 1.” Struct. J., Architect. Inst. Jpn., 526, 177–184.
Tremblay, R., Tchebotarev, N., and Filiatrault, A. (1997). “Seismic performance of RBS connections for steel moment resisting frames: Influence of loading rate and floor slab.” Proc., Stessa ’97, Kyoto, Japan, 664–671.
Tsai, K. C., Chen, W. Z., and Lin, K. C. (1999). “Experimental responses of steel reduced beam section to weak panel zone moment connections.” Proc., Workshop on Design Technologies of Earthquake-Resistant Moment-Resisting Connections in Steel Buildings, National Taiwan Univ., Taipei, Taiwan.
Uang, C., and Fan, C. (1999). “Cyclic instability of steel moment con-nections with reduced beam section.” SAC/BD-99/19, SAC Joint Venture, Sacramento, Calif.
Venti, M., and Engelhardt, M. (2000). “Test of a free flange connection with a composite floor slab.” SAC/BD-00/18, SAC Joint Venture, Sacramento, Calif.
Yu, Q. S., Gilton, C., and Uang, C. (2000). “Cyclic response of RBS moment connections: loading sequence and lateral bracing effects.” SAC/BD-00/22, SAC Joint Venture, Sacramento, Calif.
Zekioglu, A., Mozaffarian, H., and Uang, C. (1997). “Moment frame connection development and testing for the City of Hope National Medical Center.” Building to Last: Proc., Structures Congress XV, ASCE, Portland, Ore., 100–104.
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Information
Published In
Journal of Structural Engineering
Volume 128 • Issue 4 • April 2002
Pages: 441 - 451
Copyright
Copyright © 2002 American Society of Civil Engineers.
History
Received: Dec 6, 2000
Accepted: Aug 29, 2001
Published online: Apr 1, 2002
Published in print: Apr 2002
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