In this paper, an innovative post-Northridge steel special moment frame (SMF) connection that has undergone a comprehensive full-scale testing program in the last three years is presented. The connection requires only field bolting thus significantly reducing field erection time and resulting in more economical design and better performance. The connection utilizes the SidePlate load transfer technology by using two interconnecting parallel plates that sandwich and connect the beam to the column and features a physical separation, or gap, between the face of the column and the beam that plays a crucial role in reducing triaxial stress and ensuring large energy dissipation capacity. Seven full-scale SMF connection specimens with beams sizes ranging from W21×73 to W40×397 and column sections ranging from W36×231 to W36×395; HSS14xl4x7/8 to HSS18×l8×3/4 and built-up Box 30"×30"×2" were physically tested in accordance with AISC-341 prequalification requirements at the University of California San Diego. The HSS and build-up columns did not use any interior continuity plate to transfer the load. Prior to testing, substantial finite element analyses were conducted to develop and design the details of the proposed configuration to ensure desirable ductile behavior and large energy dissipation capacity. The average performance of the connection was 7% total story drift exceeding AISC-341 requirement of 4% by a large margin. This paper will give insight into some of the techniques that have been used to develop a connection with significant inelastic deformation capacity and energy dissipation including weld directionality, triaxial stress reduction and panel zone strengthening that could be educational for the development and refinement of the post-Northridge connections. The paper will also briefly report on another full-scale resiliency testing program conducted by SidePlate at the University of California San Diego. The test specimens utilized the same column and connection assembly and replaced the hinged beam that were subjected to the code level earthquakes via AISC-341's loading protocol with a new beam. The column and connection assembly were reused and no degradation in the performance observed. It proved that the developed system is resilient enough to be used after experiencing code level earthquake without replacing the whole frame.
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