Seismic Performance of Eccentrically Braced Frames with Shear Link

Abstract:

The push-over nonlinear evaluation of four eccentrically braced frame performance was conducted to assess the plastic deformation and location of plastic hinges in buildings with six, nine, twelve and fifteen stories. The excessive plastification of out-of-beam members is revealed in the majority of these buildings while the AISC design provision allows the moderate plastification in these members. Therefore, the beams out of link might be in danger of fracture of web and flange. Likewise, this was controversial evidence in Chrischurch earthquakes. In order to modify this problem either using fixed connection of braced members or using the very short shear links which have less end moment force than out-of-link beams moment strength are recommended. By this modification, the response modification coefficients are calculated for these buildings which are almost equal to the provision value. The maximum plastic rotation of shear links recommended by provisions (0.08 radian) is the upper ultimate limit to prevent emerging of out-of-link member`s instability.

• Periodical: Advanced Engineering Forum (Volume 35)
• Pages: 55-68
• DOI: https://doi.org/10.4028/www.scientific.net/AEF.35.55
• Online since: February 2020
• Authors: Sara Ansari*, Javad Tashakori, Javad Razzaghi
• Keywords: Eccentrically Braced Frames, Push Over Analysis, Response Modification Coefficient, Shear Links

References

[1] Kasai, K. and E.P. Popov, General behavior of WF steel shear link beams. J. Struct. Eng., 1986. 112 (2): pp.362-382.

DOI: 10.1061/(asce)0733-9445(1986)112:2(362)

[2] AISC, Seismic provisions for structural steel buildings. American Institute of Steel Construction 2016. ANSI/AISC 341-16.

DOI: 10.1201/b11248-16

[3] Hjelmstad, K.D. and E.P. Popov, Cyclic behavior and design of link beams. J. Struct. Eng., 1983. 109(10): pp.2387-2403.

DOI: 10.1061/(asce)0733-9445(1983)109:10(2387)

[4] Kasai, K. and E.P. Popov, Cyclic web buckling control for shear link beams. J. Struct. Eng., 1986. 112 (3): pp.505-523.

DOI: 10.1061/(asce)0733-9445(1986)112:3(505)

[5] Malley, J.O. and E.P. Popov, Shear links in eccentrically braced frames. J. Struct. Eng., 1984. 110 (9): pp.2275-2295.

DOI: 10.1061/(asce)0733-9445(1984)110:9(2275)

[6] Ramadan, T. and A. Ghobarah, Analytical model for shear-link behavior. 1995. pp.1574-1580.

[7] Ricles, J.M. and E.P. Popov, Inelastic link element for EBF seismic analysis. 1994. pp.441-463.

[8] Richards, P.W., Cyclic stability and capacity design of steel eccentrically braced frames. 2004, Dept. of Structural Engineering, Univ. of California.

[9] ETABS(9.7.0), Extended 3D Analysis of Building Systems. Computers and Structures, Inc. 1995 University Ave. Berkeley, CA 94704.

[10] SAP2000(16.1.0), Structural Analysis Program. Computers and Structures, Inc. 1995 University Ave. Berkeley, CA 94704.

[11] FEMA-356, Prestandard and commentary for the seismic rehabilitation of buildings. Federal Emergency Managment Agency, (2000).

[12] FEMA-273, NEHRP guidlines for the seismic rehabilitation of buildings. Federal Emergency Managment Agency, (1997).

[13] Okazaki, T., et al., Experimental Study of Local Buckling, Overstrength, and Fracture of Links in Eccentrically Braced Frames. J. Struct. Eng., 2005. 131(10): pp.1526-1535.

DOI: 10.1061/(asce)0733-9445(2005)131:10(1526)

[14] Hjelmstad, K.D. and E.P. Popov, Seismic behavior of active beam links in eccentrically braced frames. 1983, Report No. UBCIEERC-83/15, Earthquake Engineering Research Center, University of California at Berkeley, Richmond, CA. p. iii, 161 leaves.

[15] Clifton, G.C., et al. Multistorey steel framed building damage from the Christchurch earthquake series of 2010/2011. in The 7th International Conference on Behaviour of Steel Structures in Seismic Areas. 2012. Santiagi, Chile: 2012 Taylor & Francis Group, London.

DOI: 10.1201/b11396-6

[16] ASCE/SEI(7-16), Minimum Design Loads and Associated Criteria for Buildings and Other Structures American Society of Civil Engineers, (2017).

DOI: 10.1061/9780784414248

[17] Richards, P.W., Cyclic stability and capacity design of steel eccentrically braced frames. 2004. p. xxiv, 222 leaves.