Southern Steel Engineers provided delegated steel design engineering for this five-story Amazon Sortation Facility located in Frankfort Square, Illinois. The large-scale distribution center required extensive connection and miscellaneous steel design to support the demanding structural and operational needs of a modern sortation hub.

Connection Scope
The project featured a wide variety of connection types, including standard and non-standard shear connections, axial beam connections, vertical bracing, hollow structural section (HSS) framing at stairs, moment connections, and composite joist shear connections.
The building’s main force-resisting system consisted of heavily loaded wide-flange moment frames and vertical bracing. These elements posed challenges for maintaining bolted connections under high loads, but Southern Steel Engineers successfully achieved fully bolted connections at all primary bracing points in accordance with the client’s request.

Given the large number of composite joist connections, our team collaborated closely with the fabricator and erector to develop fully bolted composite joist details. This approach simplified erection, improved efficiency, and reduced field labor during construction.

Miscellaneous Steel Scope
The miscellaneous steel scope included the design of fifteen multi-story checkered plate infill tower stairs. The tower stairs were primarily post-supported down to the floor level, utilizing slip connections to upper floor levels for lateral stability.
Additional elements included fourteen mezzanine access stairs with checkered plate infill, two exterior roof access fall arrest ladders, one mezzanine access ramp, a roof access ladder, seventeen dock stairs, and barrier rails at vertical bracing locations.
The scope also included ARS stair and guardrail systems, chute railings, barrier rails, and shaft guardrails.