What is the purpose of the structure/ project?
A +-50 000m² industrial facility designed for the manufacturing of 580 trains for PRASA (Passenger Rail Association of South Africa). Most of the structures need to accommodate overhead cranes ranging from 2t to 2x10t tandem cranes.
What was the brief to the architect?
Design a facility to include the entire process from the extrusion of the raw steel, assembly of the coach, electrical wiring and internal ﬁtting, ﬁlming, static testing and through to the ﬁnal dynamic testing of the completed train. Also to be included is a training facility.
Was the project envisaged in steel from the start? If not – why was it built in steel in the end?
Mostly yes. There were several iterations of the design to value engineer the buildings. The initial gable structure were concrete, but later changed to steel to speedup construction and reduce the size of the foundations.
Give a brief description of the structural framing. What type of sections were used (e.g. hollow, cellular, I beams, etc.) and why?
The main frame of the buildings consists of both lattice columns and I-Columns at 8 meter grid spacing. The roof consists of steel trusses made up of angle sections. Purlins and girts consists of Metsec profiles. Metsec purlin and side rail systems are manufactured from higher strength steel, with minimum yield strength of 390 MPa in comparison to the common and local Z and C sections, which generally have yield strength in the order of 200 MPa. This allows for larger purlin and girt spacing and an overall lighter structure. The Gate House roof consists of curved cellular beams. This was mostly and architectural feature because it’s the main entrance to the site.
Were there any challenges in the fabrication of the project from the engineer’s design – if yes, please tell? Tell more about fabrication and erection process if it was complex, difficult, innovative etc.
Some roof spans were more than 29 meters. This meant splicing of trusses for ease of erection. The erection process were quite conventional. It was a challenge to obtain the correct curvature for the Curved Cellular Beams at entrance building.
What is special/ unusual/ innovative/ aesthetic about the steelwork/cladding in this project?
One of the buildings has a 12.5 meter cantilever canopy, with a gutter on the edge, spanning over a 10x48m hardstand which would be used as a laydown area. The client required a clean working space below to ease the movement of vehicles.
How did the project team work together (e.g contractor involved early, challenges/ ease of communication etc.)
The engineer communicated directly with the steel fabricator to finalise fabrication drawings. The contractor was copied in all communication and witnessed the meetings. The engineer shared the 3D Revit models and hard copies (serving as the master files) with the fabricator to ease in the translation to Tekla structural steel. The fabricator also shared his Tekla 3D model as supporting documents with his set of fabrication drawings. This all in an effort to speed up the approval process.
|Tons of structural steel used||2396|
|Structural profiles used||Curved Cellular Beams
Hot rolled sections
|Cladding profile/ type used||0.55mm Saflok 700 profile (roof)
0.55mm Trimflute profile (vertical/ side)
|Cladding area/ coverage and tonnage||77 352m|
|Project Team Role||Company|
|Steelwork Contractor 1||Churchyard and Umpleby|
|Steelwork Contractor 2||Churchyard and Umpleby|
|Steel Erector||Louwill Lefa|
|Cladding Manufacturer||Powersteel (Louwill Lefa)|
|Cladding Supplier||Global Roof Solutions (GRS)|
|Cladding Contractor||Global Roof Solutions (GRS)|
|Photographer, Photo competition||AECOM|