Structural Engineering Calculations & Stamp — Unistrut Zip Line Assembly (Therapeutic Clinic Installation) Ended

We are a specialty contractor installing a suspended Unistrut zip line assembly within a pediatric therapy clinic. The zip line will be attached to an existing pre-installed Unistrut framework (installed and certified by others). We are seeking a licensed structural engineer to review, calculate, and stamp the structural adequacy of our assembly only - the existing supporting framework is explicitly outside this scope.

Our Assembly - What Requires Engineering:
The zip line assembly consists of the following Unistrut components:

(1) Horizontal main beam — P1001T double-slotted strut channel @ 240" (20'-0")
(1) North end vertical drop — P1000T single strut @ 24"
(1) North end kicker brace — P1000T single strut @ 36"
(1) South end vertical drop — P1000T single strut @ 36"
(1) South end kicker brace — P1000T single strut @ 60"

The assembly hangs below and connects to the existing Unistrut framework via (4) 5/8" threaded rods, P1354 4-hole hinge fittings, P2484 gusseted 90° fittings, and standard Unistrut channel nuts and hardware throughout.
A wire rope zip line cable is tensioned between the bottom ends of the two vertical drop pieces, running diagonally from the South end (high point, 36" drop) to the North end (low point, 24" drop) across the 20'-0" horizontal span, creating approximately 12" of elevation change (5% grade) for rider travel.

Design Loading Requirements:
The assembly is intended for therapeutic pediatric use in a clinical environment. The engineer should design for appropriate live loads for this application, but at minimum we anticipate:

Dynamic rider load on the cable trolley
Cable tension forces transferred into the vertical drop pieces and kicker braces
All resulting loads transferred into the existing framework at the (4) threaded rod connection points

Scope of Engineering Services Requested:

Review of the assembly configuration as described and shown in the provided elevation drawing
Structural calculations confirming adequacy of all Unistrut members, connections, and hardware for the intended loading
Confirmation that the (4) 5/8" threaded rod connections to the existing frame are adequate to transfer loads (note: engineer is not certifying the existing frame itself, only the connection interface loads)
Stamped and signed drawings/calculations suitable for submission to the facility and/or local AHJ (Authority Having Jurisdiction) if required

What We Will Provide to the Engineer:

Elevation drawing (CAD) showing all member sizes, lengths, and geometry
Complete hardware/materials list with Unistrut part numbers
Photos of the existing framework at the new site
Photos of an identical installed assembly at an existing site for reference

Explicitly Outside Scope:

The existing Unistrut swing/therapy framework (installed by others, certified separately)
The zip line cable, trolley, and rider hardware (separate product, certified by manufacturer)
The building structure above the existing framework

Deliverables Expected:

Signed and stamped structural calculations
Stamped drawing(s) suitable for permitting/facility submission
Engineer must be licensed in MISSOURI read less