Unified Flexural Resistance Equations for Stability Design of Steel I-Section Members: Uniform Bending Tests
Publication: Journal of Structural Engineering
Volume 134, Issue 9
Abstract
The 2004 AASHTO and 2005 AISC provisions for flexural design of steel I-section members have been revised in their entirety relative to previous specifications to simplify their logic, organization, and application, while also improving their accuracy and generality. This paper evaluates the lateral-torsional and flange local buckling (LTB and FLB) predictions from these and previous specifications versus uniform bending experimental test results. A total of 154 rolled and 123 welded I-section member LTB tests, and 11 rolled and 36 welded I-section member FLB tests are considered. Reliability indices are estimated for load and resistance factor design (LRFD) of buildings based on the test statistics combined with established statistics for material and fabrication bias factors and the ASCE 7 load model. The notional reliability for LTB is found to be reasonably constant and consistent with the targeted level in the first AISC LRFD specification of 1986. The unified equations, combined with a design-oriented procedure for calculation of elastic LTB factors, are shown to capture the test results accurately throughout the inelastic and elastic LTB ranges, leading to substantial liberalization of the calculated resistances in certain cases. The mean resistances for inelastic LTB and FLB are captured accurately by a linear equation in the corresponding slenderness parameters. The reliability for FLB is found to be slightly higher than that for LTB.
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Acknowledgments
The writers express their sincere thanks to the members of AISC TC4 (Louis Geschwindner, Chair), the AISI LRFD Specification Task Force (Dennis Mertz, Chair), and the AASHTO T14 Technical Committee for Steel Design (Ed Wasserman, Chair) for their efforts in the updating of the AISC and AASHTO flexural strength provisions. Also, the NCHRP Project 12-38 (Dann Hall and Chai Yoo, co-PIs) and 12-52 (John Kulicki, PI) teams are thanked for providing substantial contributions. Special thanks are extended to Michael Grubb of Bridge Software Development International, Ltd. for extensive input on all attributes of the developments. Professors Ted Galambos of the University of Minnesota and Bruce Ellingwood of Georgia Institute of Technology provided valuable input. Professors Yuhshi Fukumoto and Masahiro Kubo of Nagoya University, Japan, catalogued a large number of LTB tests originally in Fukumoto and Kubo (1977). The research by these investigators greatly facilitated the data collection and analyses conducted in this study. Professor Richard Sause and Mr. Daming Yu of Lehigh University secured a number Lehigh reports for the writers. This research was funded by Professional Services Industries, Inc. and the Federal Highway Administration, and by the ASCE Structural Engineering Institute. The financial support from these organizations is gratefully acknowledged. The opinions, findings and conclusions expressed in this paper are the writers and do not necessarily reflect the views of the above-mentioned individuals, groups, and organizations.
References
AASHTO. (1998). AASHTO LRFD bridge design specifications, 2nd Ed. with 1999, 2000, 2001, 2002 and 2003 interim provisions, Washington, D.C.
AASHTO. (2004). AASHTO LRFD bridge design specifications, 3rd Ed. with 2005 interim provisions, Washington, D.C.
Abe, H., and Mizukoshi, N. (1973). “Buckling tests on plate girders under bending.” Annual Meeting of the Japanese Society of Civil Engineers, preprint, Japan Society of Civil Engineers, Tokyo.
Adams, P. F., Lay, M. G., and Galambos, T. V. (1964). “Experiments on high strength steel members.” Fritz Engineering Laboratory Rep. No. 297.8, Lehigh Univ., Bethlehem, Pa.
AISC. (1986). Load and resistance factor design specification for structural steel buildings, Chicago.
AISC. (1989). Specification for structural steel buildings, allowable stress design and plastic design, Chicago.
AISC. (1999). Load and resistance factor design specification for structural steel buildings, Chicago.
AISC. (2005). “Specification for structural steel buildings.” ANSI/AISC 360-05, Chicago.
American Iron and Steel Institute (AISI). (1974). The variation of product analysis and tensile properties of carbon steel plates and wide flange shapes, Washington, D.C.
ASCE. (2006). “Minimum design loads for buildings and other structures.” ASCE/SEI 7-05, Reston, Va.
ASTM. (1997). “Standard method for Young’s modulus, tangent modulus and chord modulus.” ASTM E111-97, Philadelphia.
ASTM. (2000). “Standard test methods for tension testing of metallic materials.” ASTM E8-00b, Philadelphia.
Baker, K. A., and Kennedy, D. J. L. (1984). “Resistance factors for laterally unsupported steel beams and biaxially loaded steel beam columns.” Can. J. Civ. Eng., 11(4), 1008–1019.
Bansal, J. P. (1971). “The lateral instability of continuous steel beams.” Doctoral dissertation, Univ. of Texas, Austin, Tex.
Bartlett, F. M., Dexter, R. J., Graeser, M. D., Jelinek, J. J., Schmidt, B. J., and Galambos, T. V. (2003). “Updating standard shape material properties database for design and reliability.” Eng. J., 40(1), 2–14.
Basler, K., Yen, B. T., Mueller, J. A., and Thurlimann, B. (1960). “Web buckling tests on welded plate girders.” WRC Bulletin No. 64, Welding Research Council, New York.
Bradford, M. A., and Hancock, G. J. (1984). “Elastic interaction of local and lateral buckling in beams.” Thin-Walled Struct., 2(1), 1–25.
Canadian National Standards Association (CSA). (1984). “Steel structures for buildings—Limit states design.” National Standard of CanadaCAN3-S16.1-M84, Rexdale, Ont., Canada.
Carskaddan, P. S. (1968). “The bending behavior of slender-web girders with A514 steel flanges.” Applied Research, Rep. No. 57.019-904 (5) (AS-EA-23-ps), U.S. Steel Corporation, Pittsburgh.
Cherry, S. (1960). “The stability of beams with buckled compression flanges.” Struct. Eng., 38(9), 277–285.
Cooper, P. B. (1967). “Strength of longitudinally stiffened plate girders.” J. Struct. Div., 93(2), 419–451.
Cooper, P. B., Galambos, T. V., and Ravindra, M. K. (1978). “LRFD criteria for plate girders.” J. Struct. Div., 104(9), 1389–1407.
D’Apice, M. A., Fielding, D. J., and Cooper, P. B. (1966). “Static tests on longitudinally stiffened plate girders.” WRC Bulletin No. 117, Welding Research Council, New York.
Dibley, J. E. (1969). “Lateral torsional buckling of I-sections in Grade 55 steel.” Proc., Institution of Civil Engineers, Vol. 43, 599–627, Institution of Civil Engineers, London.
Dibley, J. E. (1970). “A preliminary investigation into the use of high-strength structural steel in structures designed plastically.” BIRSA Open Rep. No. EG/A/13/70, British Steel Corporation, London.
Dimitri, J. R., and Ostapenko, A. (1970). “Pilot tests on the static strength of unsymmetrical plate girders.” WRC Bulletin No. 156, Welding Research Council, New York.
Driscoll, G. C., and Beedle, L. S. (1957). “The plastic behavior of structural members and frames.” Weld. J. (Miami, FL, U.S.), 36(6), 275-s–286-s.
Dux, P. F., and Kitipornchai, S. (1983). “Inelastic beam buckling experiments.” J. Constr. Steel Res., 3(1), 3–9.
Ellingwood, B. E., Galambos, T. V., MacGregor, J. G., and Cornell, C. A. (1980). “Development of a probability based load criterion for American National Standard A58.” NBS Publication No. 577, Washington, D.C.
Ellingwood, B. E., MacGregor, J. G., Galambos, T. V., and Cornell, C. A. (1982). “Probability-based load criteria: Load factors and load combinations.” J. Struct. Div., 108(5), 978–997.
Frost, R. W., and Schilling, C. G. (1964). “Behavior of hybrid beams subjected to static loads.” J. Struct. Div., 90(3), 55–88.
Fukumoto, Y. (1976). “Lateral buckling of welded beams and girders in HT 80 steel.” Preliminary Rep. of 10th Congress, International Association for Bridge and Structural Engineering, Tokyo, 403–408.
Fukumoto, Y., Fujiwara, M., and Watanebe, N. (1971). “Inelastic lateral buckling tests on welded beams and girders.” Proc., Japan Society of Civil Engineers, Tokyo, Vol. 189, 39–51 (in Japanese).
Fukumoto, Y., Itoh, Y., and Kubo, M. (1980). “Strength variation of laterally unsupported beams.” J. Struct. Div., 106(1), 65–181.
Fukumoto, Y., and Kubo, M. (1971). “Inelastic lateral buckling strength of monosymmetrical I-beams.” Annual Meeting of the Japanese Society of Civil Engineers, preprint (in Japanese).
Fukumoto, Y., and Kubo, M. (1972). “Lateral buckling strength of girders with bracing systems.” Preliminary Rep. of 9th Congress, International Association for Bridge and Structural Engineering, Amsterdam, The Netherlands, 299–304.
Fukumoto, Y., and Kubo, M. (1977). “An experimental review of lateral buckling of beams and girders.” International Colloquium on Stability of Structures Under Static and Dynamic Loads, ASCE, New York, 541–562.
Galambos, T. V. (1998). Guide to stability design criteria for metal structures, T. V. Galambos, ed., Structural Stability Research Council, Wiley Interscience, New York.
Galambos, T. V. (2004). “Reliability of the member stability criteria in the 2005 AISC Specification.” Int. J. Steel Struct., 4(4), 223–230.
Galambos, T. V., Ellingwood, B. E., MacGregor, J. G., and Cornell, C. A. (1982). “Probability-based load criteria: Assessment of current design practice.” J. Struct. Div., 108(5), 959–977.
Galambos, T. V., and Ravindra, M. K. (1976). “Load and resistance factor design criteria for steel beams.” Research Rep. No. 27, Structural Division, Civil and Environmental Engineering Dept., Washington Univ., St. Louis.
Galambos, T. V., and Ravindra, M. K. (1978). “Properties of steel for use in LRFD.” J. Struct. Div., 104(9), 1459–1468.
Green, P. S. (2000). “The inelastic behavior of flexural members fabricated from high performance steel.” Doctoral dissertation, Lehigh Univ., Bethlehem, Pa.
Hasham, A. S., and Rasmussen, K. J. R. (2002). “Interaction curves for locally buckled I-section beam-columns.” J. Constr. Steel Res., 58(2), 213–241.
Hisamitu, S., and Okuto, K. (1971). “Lateral buckling tests on beams with residual stresses.” Annual Meeting of AIJ, Architectural Institute of Japan, Tokyo, preprint (in Japanese).
Holtz, N. M., and Kulak, G. L. (1973). “Web slenderness limits for compact beams.” Structural Engineering Rep. No. 43, Univ. of Alberta, Alta., Canada.
Holtz, N. M., and Kulak, G. L. (1975). “Web slenderness limits for noncompact beams.” Structural Engineering Rep. No. 51, Univ. of Alberta, Alta., Canada.
Iyengar, S. N. S., Lu, L.-W., and Beedle, L. S. (1969). “Experiments on A512 Grade 65 steel beams.” Fritz Engineering Laboratory Rep. No. 343.4, Lehigh Univ., Bethlehem, Pa.
Janss, J., and Massonnet, C. (1967). “The extension of plastic design to steel A52.” Publications of the IABSE, 27, 15–30.
Johnson, D. L. (1985). “An investigation into the interaction of flanges and webs in wide flange shapes.” Proc., Annual Technical Session, Structural Stability Research Council, Univ. of Missouri-Rolla, Rolla, Mo., 395–405.
Kennedy, D. J. L., and Baker, K. A. (1984). “Resistance factors for steel highway bridges.” Can. J. Civ. Eng., 11(2), 324–334.
Kennedy, D. J. L., and Gad Aly, M. (1980). “Limit states design of steel structures—Performance factors.” Can. J. Civ. Eng., 7(1), 45–77.
Lee, G. C., Ferrara, A. T., and Galambos, T. V. (1964). “Experiments on braced wide-flange beams.” Welding Research Council Bulletin No. 99, Welding Research Council, New York.
Lee, G. C., and Galambos, T. V. (1962). “Post-buckling strength of wide-flange beams.” J. Engrg. Mech. Div., 88(1), 59–75.
Lew, H. S., and Toprac, A. A. (1968). “The static strength of hybrid plate girders.” S.F.R.L. Technical Rep. No. P550-11, Structures Fatigue Research Laboratory, Dept. of Civil Engineering, Univ. of Texas, Austin, Tex.
McDermott, J. F. (1969). “Plastic bending of A514 steel beams.” J. Struct. Div., 95(9), 1851–1871.
Mirza, S. A., and MacGregor, J. G. (1982). “Probabilistic study of strength of reinforced concrete members.” Can. J. Civ. Eng., 9(3), 431–448.
Morikawi, N., and Fujino, S. (1971). “Ultimate bending strength of plate girders.” Annual Meeting of the Japanese Society of Civil Engineers, preprint (in Japanese).
Nethercot, D. A., and Trahair, N. S. (1976). “Lateral buckling approximations for elastic beams.” Struct. Eng., 54(6), 197–204.
Owen, D. R. J., Rockey, K. C., and Skaloud, M. (1970). “Ultimate load behavior of longitudinally reinforced webplates subjected to pure bending.” IABSE Publ., 30(1), 113–148.
Prasad, J., and Galambos, T. V. (1963). “The influence of the adjacent spans on the rotation capacity of beams.” Fritz Engineering Laboratory Rep. No. 205H.12, Lehigh Univ., Bethlehem, Pa.
Richter, J. F. (1998). “Flexural capacity of splender web plate girders.” M.S. thesis, Univ. of Texas, Austin, Tex.
Suzuki, T., and Kubodera, M. (1973). “Inelastic lateral buckling of steel beams.” Annual Meeting of Architectural Institute of Japan, Architectural Institute of Japan, Tokyo, preprint (in Japanese).
Suzuki, T., and Ono, T. (1970). “Experimental study of inelastic beams. 1: Beam under uniform moment.” Transactions of the Architectural Institute of Japan, Architectural Institute of Japan, Tokyo, Vol. 168, 77–84 (in Japanese).
Suzuki, T., and Ono, T. (1973). “Inelastic lateral buckling of steel beams.” Annual Meeting of Architectural Institute of Japan, Architectural Institute of Japan, Tokyo, preprint (in Japanese).
Suzuki, T., and Ono, T. (1976). “Deformation capacity of high-strength steel members.” Preliminary Rep., 10th Congress of the International Association for Bridge and Structural Engineering, preprint.
Udagawa, K., Saisho, M., Takanashi, K., and Tanaka, H. (1973). “Experiments on lateral buckling of H-shaped beams subjected to monotonic loadings.” Transactions of the Architectural Institute of Japan, Vol. 48(212), 22–33.
Wakabayashi, M., Nakamura, T., Okamura, N. (1970). “Studies on lateral buckling of wide flange beams (1).” Disaster Prevention Research Institute Annuals, Vol. 14A, Kyoto Univ., Kyoto, Japan (in Japanese).
White, D. W. (2008a). “Structural behavior of steel.” Chap. 6, Steel bridge design handbook, National Steel Bridge Alliance, Chicago.
White, D. W. (2008b). “Unified flexural resistance equations for stability design of steel I-section members—Overview.” J. Struct. Eng., 134(9), 1405–1424.
White, D. W., Barker, M., and Azizinamini, A. (2008). “Shear strength and moment-shear interaction transversely-stiffened steel I-girders.” J. Struct. Eng., 134(9), 1437–1449.
White, D. W., and Jung, S.-K. (2003a). “Simplified lateral-torsional buckling equations for I-and channel-section members.” Structural Engineering, Mechanics and Materials Rep. No. 24a, School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta.
White, D. W., and Jung, S.-K. (2003b). “Simplified lateral-torsional buckling equations for singly-symmetric I-section members.” Structural Engineering, Mechanics and Materials Rep. No. 24b, School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta.
White, D. W., and Jung, S.-K. (2004). “Unified flexural resistance equations for stability design of steel I-section members—Uniform bending tests.” Structural Engineering, Mechanics and Materials Rep. No. 28, School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta.
White, D. W., and Jung, S.-K. (2007). “Effect of web distortion on the buckling strength of noncomposite discretely-braced I-beams.” Eng. Struct., 29(8), 1872–1888.
White, D. W., and Kim, Y. D. (2008). “Unified resistance equations for stability design of steel I-section members—Moment gradient tests.” J. Struct. Eng., 134(9), 1471–1486.
Wong-Chung, A. D., and Kitipornchai, S. (1987). “Partially braced inelastic beam buckling experiments.” J. Constr. Steel Res., 7(3), 189–211.
Yu, D., and Sause, R. (2002). “Regression study on the inelastic lateral torsional buckling strength of I-beams.” ATLSS Center, Lehigh Univ., Bethlehem, Pa.
Yura, J. A., Galambos, T. V., and Ravindra, M. K. (1978). “The bending resistance of steel beams.” J. Struct. Div., 104(9), 1355–1369.
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Published In
Journal of Structural Engineering
Volume 134 • Issue 9 • September 2008
Pages: 1450 - 1470
Copyright
© 2008 ASCE.
History
Received: Aug 24, 2005
Accepted: May 16, 2006
Published online: Sep 1, 2008
Published in print: Sep 2008
Notes
Note. Associate Editor: Scott A. Civjan
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