Pre-cast concrete wall structures, and methods for manufacturing and installing the same

A wall segment for constructing a foundation wall of a building, the wall segment comprising:

• a pre-cast concrete monolithic body including a ground-engaging footer and a vertical wall supported by the footer and extending upwardly from the footer;
• wherein the monolithic body is freestanding;
• wherein the monolithic body includes a first end and a second end spaced from one another in a longitudinal direction of the monolithic body, wherein the vertical wall extends longitudinally beyond the footer at the first end and the footer extends longitudinally beyond the vertical wall at the second end;
• wherein the vertical wall includes a tongue at one of the first and second ends of the monolithic body, and the vertical wall includes a groove at the other of the first and second ends of the monolithic body;
• and
• a pair of identical connection brackets, wherein a portion of each connection bracket is embedded in the monolithic body, the pair of connection brackets including a first connection bracket having an outer face flush with an outer surface of the tongue and a second connection bracket having an outer face flush with an inner face of the groove.