The Earthquake Engineering Online Archive

Experimental and analytical studies of steel connections and energy dissipators

Yang, Tzong-Shuoh; Popov, Egor P.

UCB/EERC-95/13, Earthquake Engineering Research Center, University of California, Berkeley, 1995-12, 191 pages (515/Y25/1995)

Nonlinear structural response spectra for strength, ductility, energy and number of yield reversals as a function of building period and structure strength for several strong motion earthquakes are presented. These results are compared with conventionally evaluated elastic response spectra and code criteria. The basic reasons for the fractures that occurred in steel moment-resisting connections during the 1994 Northridge earthquake are examined from a fundamental point of view. Three SAC pre-Northridge specimen tests subjected to cyclic loading are critically examined. Good comparisons are found using the above theory. Next, the beam strength is reduced by drilling holes in flanges to protect the steel connection. Experiments on eight W12X26 beams with different perforation patterns are reported. Two large size connections with perforated beam flanges are tested. The design methods of braced frames with Slotted Bolted Connections (SBCs) are reported. The advantages of using such frictional connections are demonstrated by comparing seismic structural responses. Finally, the Rotational Slotted Bolted Connection (RSBC), a new variety of SBC which is in essence a rotational friction damper, is designed for use in steel moment-resisting connections.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-95-13.pdf (11 MB)