Patent ID: 8297023

Claim:
In a stackable steel column assembly comprising rectangular steel upper and lower hollow columns and a rectangular steel coupler sized to receive the upper end of the lower column and the lower end of the upper column with the column load of said upper column being transferred to said lower column in compression, where the coupler has at least one beam connector extending laterally outwardly from a lateral side thereof on which a floor load is imposed in shear, and including means for limiting the vertical movement of said coupler relative to said lower column and for transferring any floor load imposed on the coupler to the lower column in shear, the improvement: wherein the column load of said upper column is supported in compression by said lower column without abutment of said columns and without through-column apertures, and wherein the vertical movement of said coupler relative to said lower column is limited and the transfer of any floor load from said coupler to said lower column is effected without through-column apertures or the welding of said coupler to said lower column, wherein said coupler includes a flat steel plate extending through horizontal slots at the same height in opposing lateral sides of the coupler near the vertical midpoint thereof, the lower end of said upper column abutting said plate to transfer the column load thereto in compression and said plate abutting the upper end of said lower column to transfer thereto in compression any column load applied to said plate so that the column load is transferred from said upper column to said lower column through said plate in compression, said plate obviating the need for registration of the walls of said upper column with the walls of said lower column, the abutment of said plate with the upper end of said lower column limiting the downward movement of said coupler relative to said lower column and effecting transfer of any floor load from said coupler to said lower column in compression.