Experimental investigation of shop welded link-to-column connections in eccentrically braced frames

The link-to-column connection is a critical element affecting the safety and performance of seismic-resistant steel eccentrically braced frames (EBFs). In the US, the AISC Seismic Provisions for Structural Steel Buildings requires that satisfactory performance of link-to-column connections be verified by testing under a prescribed loading protocol. To-date, very few link-to-column connection details have passed these testing criteria. Consequently, the availability of link-to-column connection details with demonstrated satisfactory performance remains a largely unsolved problem for construction of EBFs in the US. The writers recently completed a program of pilot tests on link-to-column connections, using welded details that are intended for shop welding. These tests have shown excellent connection performance, satisfying the performance requirements of the AISC Seismic Provisions. This paper will describe the development of these connection details, provide a summary of test results, and discuss the design implications of this research program.