Full-scale test on weld-free building structure with knee brace dampers

This paper presents an innovative structural system, named weld-free system, developed to overcome the difficulty in quality assurance encountered in construction of steel moment resisting frames with conventional welded connections. The proposed structural system adopts a mechanical joint equipped with knee brace damper, which can be classified as a kind of buckling restrained braces. An experimental verification was conducted on a full-scale three-story weld-free building structure. The primary objective is to verify the constructability, seismic performance, and collapse mechanism of weld-free structures under bilateral loading. The test clearly reveals the efficiency of the weld-free system in enhancing large and stable hysteresis loops, while beams and columns above the base can be proportioned to remain elastic under the design earthquakes.