Construction World June 2022

The southern elevation and the five wind-load columns.

these were also extended to roof height using structural steel members. The tilt-up panels were used to enclose the perimeter of the warehouse. 8,72 m wide, their height varies between 4,55 m to 8.35 m; the largest panel measures 8,72 x 8,35 m. Supported by the column foundations, the panels double up as the retaining walls on two of the building’s sides. Commenting on the project, Superstruct managing director, Bruere Visser says that the lifting and placing of panels as large as these is an operation which requires careful planning and execution. “The placement of lifting anchors in the panels must be accurately calculated to avoid the bending and stress cracking induced by secondary loading during installation. The casting bed positions and installation process also needed to be planned to achieve a streamlined cost-effective operation. This minimised any potential for damage during installation and numerous casting beds were required to achieve these logistics.” Superstruct’s precast columns were cast with starter bars for meshing with the column-base rebar and HD bolts were cast into at the top of the columns for attaching the structural steel I beams. The bolts were cast in pockets to provide some flexibility when attaching the steel I beams. Visser added that all the blindings were checked for levels before the columns were placed and before the columns were in position they were shimmed to the correct height and plumbed to the correct alignment. Where necessary, further alignment adjustments were made immediately after the foundation concrete had been poured. Sutherland has offices in Cape Town, Johannesburg, Durban and Nairobi. It has pioneered precast industrial design since the early 2000’s has successfully completed over 400 000 m 2 of warehousing in the Plumbago Precinct in Pomona. Donnie Smith notes that the Pomona gable-end columns were some of the largest precast columns that he and the

One of the wind-load columns prior to casting.

PROFESSIONAL TEAM Architects: Empowered Spaces Structural and Civil Engineers: Sutherland Engineers Quantity Surveyor: MLC Main Contractor: Bantry Construction Precast Concrete Subcontractor: Superstruct

Sutherland Engineers have designed to date. To further save costs in erecting these columns, it was decided to taper them from the foundation to the girder which was a design feat in itself. He added that Bantry Construction and Superstruct should be commended for the role they played in achieving the goals. 

“The placement of lifting anchors in the panels must be accurately calculated to avoid the bending and stress cracking induced by secondary loading during installation.”

25 CONSTRUCTION WORLD JUNE 2022