NEHRP Clearinghouse
- Title
- Behavior of Long Links in Eccentrically Braced Frames.
- File
- PB92143056.pdf
- Author(s)
- Engelhardt, M. D.; Popov, E. P.
- Source
- National Science Foundation, Washington, DC.; American Iron and Steel Inst., Washington, DC., January 1989, 415 p.
- Identifying Number(s)
- UCB/EERC-89/01
- Abstract
- The report describes an experimental investigation and associated studies on long, flexural yielding links in seismic-resistant EBFs. EBFs provide ductile behavior under severe earthquake loads by restricting yielding to beam segments called links. Although short, shear yielding links are preferred because of their demonstrated excellent plastic rotation and energy dissipation capacities, longer, flexural yielding links can offer important architectural advantages. The central focus of the report is an experimental investigation on fourteen 2/3 scale subassemblages subject to cyclic loads. The subassemblages model a portion of a single-diagonal EBF with the links attached to the columns. The testing program showed that the dominant failure mode for long links attached to columns is fracture of the link flange at the link-to-column connection. The recommendation is made that long links attached to columns not be used in EBFs. The test results suggest, however, that long links located between two braces can provide acceptable performance, although short links are still preferred for best overall performance. Preliminary design recommendations are provided for the use of long links not attached to columns. Included are recommendations on the design yield strength, ultimate strength, plastic rotation capacity and stiffening requirements for long links.
- Keywords
- ; Seismic design; Earthquake resistant structures; Dynamic loads; Beams (Supports); Structural vibration; Steel structures; Deformation; Test facilities; Frames; Dynamic response; Earthquake engineering; Shear stress; Bending moments; Cyclic loads; Plastic analysis; Loads (Forces); Structural members