Pre-engineered industrial shed design — 60 m clear span.
Case study: ASTCAD delivered the structural design and detailing for a 60 m clear-span pre-engineered industrial shed in tropical-cyclone Region D — including portal frames, purlins, girts, mezzanine and crane runway beams to AS 4100 and AS/NZS 1170.2.
Project overview
A Darwin-based industrial fabricator engaged ASTCAD for the structural design of a new 60 m clear-span workshop housing two 12.5-tonne overhead cranes and a 6 m mezzanine office. The site is within cyclonic Region D, requiring full importance-level 2 wind design with corner cladding pressure coefficients.
The challenge
The client needed the largest practical clear span for crane operation, plus a mezzanine that didn’t interfere with the crane runway, all within a tight footprint constrained by existing site services. Region D wind loading and the requirement for the structure to remain in service immediately after a cyclonic event drove the design.
Our approach
- Tapered portal frame design optimised for 60 m clear span with internal mezzanine columns
- Crane runway beam design for two 12.5 t cranes per AS 1418.18
- Wind loading per AS/NZS 1170.2 Region D — wind speed Vu = 88 m/s
- Connection design to AS/NZS 5131 CC3 (high consequence of failure)
- Mezzanine and stair design to AS 1657 with edge protection
Deliverables
- Structural drawings — portal frames, purlins, girts, bracing
- Crane runway beam shop drawings with connection details
- Mezzanine framing plans and stair details
- Engineering certifications for council and building surveyor sign-off
- Tekla model and material take-off for fabrication tender
Outcome
The PEB was fabricated and erected in 16 weeks — ahead of programme. The Tekla model went straight into the fabricator’s CNC line, eliminating shop-floor mark-out. The structure has weathered two cyclonic events since commissioning, with no damage or repair required.