Successful Structural Steel Warehouse Project In KZN
The building is roofed and clad with a high tech, premium grade of coated steel that provides not only long life in service but also an attractive finish. The building also features the innovative usage of steel on many levels.
Professional team – steel
Project Name: Pepkor Distribution Centre, Hammarsdale
Developer/ Client: Rokwill Property Development
Architects: TC Design Architects
Structural Engineers: EDS Engineering Design Services (Pty) Ltd
Main Contractor: Abbeydale Building and Civils (Pty) Ltd
Steelwork Contractor: Cadcon Steel Construction and Engineering
Steel Erector: Fanie Leibrandt Steel Erectors
Cladding and Roofing Manufacturer: Macsteel Service Centres (Pty) Ltd
Cladding Supplier: Macsteel Services Centres and Engineering
Cladding Contractor: Impact Engineering (Pty) Ltd
Photographs by: Reinhard Swanepoel
According to GD Joubert, Senior Associate at structural engineers, EDS Engineering Services, “The warehouse offers a mixed use area of 82 000m2 consisting of covered warehouse space – 440m x 180m – also providing office spaces of 3 000 m2 and 1 800 m2 for companies Ackermans and Speciality and a total of a further four node offices each of 500m2 each”.
“The brief called for approximately 17.35m clear height to underside of eaves. Materials of construction consisting of reinforced concrete and structural steel to structural engineer’s design with appropriate corrosion protection where necessary. It was envisaged from the outset that the warehouse would be constructed largely of structural steel. The main support columns of the warehouse are concrete up to 12.6m and 17m from FFL. The remainder of the structure was constructed from structural steel.
Structural steel was strengthened locally to allow for the installation of solar panels to a roof area of approximately 15,000m2”.
“The structural system used for the building was based on a girder truss system carrying lateral trusses that makes up the main elements of the roof. Various steel profiles were used for the building, including the structural, roofing and cladding elements”, says Joubert.
According to Dave Reid, general manager at Macsteel, the project was completed with Macsteel’s Novotexi 440 concealed-fix roofing profile using BlueScope’s legendary ZINCALUME ® steel in coating mass AZ150 and total coated thickness (TCT) 0.53mm on the roof. The cladding was the company’s Wide-span 762 formed using Clean COLORBOND° coating mass AZ150 at 0,47 mm TCT on the sides. COLORBOND° “Significantly, Macsteel roll- formed 660 tonnes on site with their mobile roll forming machines in a record time” says Reid.
According to Arno Hanekom, regional manager of BlueScope Southern Africa, a critical element to the design of the roof was the selection of ZINCALUME® and Clean COLORBOND° steels. “The coating on ZINCALUME® comprises 55% aluminum, 43.5% zinc and 1.5% silicon. It has excellent corrosion performance, forming capabilities and is available in high strength grades. In the case of the Pepkor DC, product was supplied in coating mass AZ150, TCT 0,53mm and at longitudinal tensile strength G550. In addition, ZINACALUME® offers an above average solar reflective index when compared with other unpainted roofing materials such as galvanized steel. “The continuous hot dip process used to produce ZINCALUME® steel provides a surface coating which has a shiny appearance with a uniform small spangle. This coating, patented to BlueScope, determines the solar absorptance of the upper surface.
In short, ZINCALUME® steel minimises the fraction of the sun’s energy absorbed by the roof and maximises the fraction reﬂected. With a new SRI value of 63, ZINCALUME® offers superior performance over time when compared to all other unpainted materials. It keeps this property much longer than comparable materials and is not prone to corrosion even in a harsh climate”.
Shades of grey cladding
The warehouse’s cladding was erected by Impact Engineering. Clean COLORBOND°, was supplied in coating mass AZ150, TCT 0,47mm and at longitudinal tensile strength G550. Colours were Armour Grey and Volcanic Grey, used to keyline prominent structural elements on the side of the building in a visually pleasing way. In addition, the high performance paint system on Clean COLORBOND° incorporates various sustainability and long life features including our well known Thermatech° coating system”.
The remarkable aspects of this project were the speed at which the steelwork was erected as well as the completion of the overall project. A total of 2500 ton of structural steel was erected (Main warehouse 2180 tons and canopies / offices 320 tons = 2 500 tons), with the erection commencing on 14 November 2016, and reaching completion of the main warehouse structure (2180 Ton) at the end of March 2017.
BlueScope Steel Southern Africa (Pty) Ltd