The connection of the truss elements that would form the primary structure for the Table Top, to the concrete stair and elevator core, was achieved through special corner connectors. These large steel connectors were fabricated at the Walters shop and cast into the concrete core as it was going up. This would provide for significant moment resistance at the meeting of the steel truss and the concrete core, which was particularly important during erection as the truss elements were required to cantilever temporarily until the legs were erected to support the truss.

Image: Carruthers and Wallace

When you examine the back side of the corner connector you can see where the reinforcing steel from the concrete core will join with the structural steel of the connector.

Image: Carruthers and Wallace

A view looking at the interior of the corner pieces. These are designed to accommodate the thickness of the concrete core wall that gets poured "inside" the element.

Image: PCL Constructors

Not all of the corner steel pieces are fabricated in the same manner. It depends on what the piece is being designed to receive in terms of the truss attachments.

Image: PCL Constructors

Here you can see the ironworkers lowering a corner connector into position prior to the placement of the back side of the formwork for the core and of course prior to the pouring of the concrete. The steel reinforcing in the concrete core will be tied to the steel connector to provide moment (bending) resistance in the connection.

Image: Carruthers and Wallace

Here you can see one of the initial truss components that has been attached to one of the steel elements that has been cast into the corner of the concrete core.

Various steel connectors are visible that have been cast into the concrete in preparation for the attachment of the truss elements.

Image: PCL Constructors