The present invention relates to an improved system for connecting beams of a building structure that is highly resistant to shear and moment forces as well as relatively strong, stiff and ductile and complies with the standard building codes. The system comprises a primary beam stub comprising a beam slot and a support fin respectively disposed in a web portion and a flange portion thereof; a secondary beam stub configured for extending orthogonally through the beam slot of the primary beam stub; and a tubular column comprising a set of opposing beam slots formed and spaced circumferentially along a surface thereof configured for receiving the primary beam stub and the secondary beam stub passing through the set of opposing beam slots, wherein the primary beam stub and the secondary beam stub are coupled to the beams.