Full moment connection collar systems

A full-moment column collar, comprising:

• four collar flange assemblies, each collar flange assembly including an upper transverse element, a lower transverse element, and a bridging component connecting the upper and lower transverse elements, and
• four collar corner assemblies, each collar corner assembly including first and second expanses defining a corner and a standoff portion extending from the corner, the standoff portion having a distal T-shaped structure,
• wherein:
• each collar corner assembly is configured to connect two adjacent collar flange assemblies,
• each collar corner assembly has a multi-axis alignment structure extending from the first expanse for vertically positioning a lower transverse element of a respective collar flange assembly, and
• the alignment structure has a positioning surface, each lower transverse element having a surface shaped inversely to the positioning surface of a respective alignment structure.