This paper presents the results of an experimental verification on a full-scale three story 'weld-free' structure, which is proposed as an innovative steel frame adopting mechanical joints equipped with buckling-restrained type knee brace dampers for wide-flange moment frames. Major findings are as follows: (1) The weld-free structure exhibits stable hysteresis behavior under 0.04 radian drift angle in-plane, (2) The yield mechanism by plastification of dampers and column bases meet the target mechanism, (3) The structure collapses by overall buckling of dampers and lateral-torsional buckling of beams but the maximum drift angle attained 0.10 radian preserving sufficient lateral resistance.