Award for Excellence 2018, Tension Structures Greater than 2000sqm

Parap Leisure Centre in Darwin underwent a $15.4 million upgrade in 2017. As part of the development, the centre received a new 50m Olympic pool, 25m pool, new office, entry, kiosk/café, amenities & limited dry and zero-depth wet play area.

Our scope was the design & construction of a large clear span shade canopy over the 50m pool. The structure spans 56.5m, is 11.5m high and 55m long, utilising Serge Ferrari TX30-III fabric to deliver an ambient yet functional shade solution.

The purpose of this project was to provide a large-scale shade canopy over the pool that protected swimmers from harsh UV rays, but also remained bright & airy underneath the canopy using translucent fabric.

The client requested a structure that was functional and guaranteed to provide adequate shade over the outdoor pool. The canopy was also required to be aesthetically pleasing, complementing the myriad of newly designed equipment and facilities at the centre.

The steelwork design appears simple, however spanning 56m using a single CHS designed to resist cyclonic wind loads required a large 460mm dimeter CHS pipe that was anything but simple to install!

Each CHS arch was detailed and fabricated in 5 x 11m long Sections that were bolted together on the ground into one long arch before lifting. The erection process was very complex due to the length and weight of the arch and required the use of a 200-tonne crane. We completed lift studies before lifting the steelwork to ensure the lifting method would not overstress the steelwork.

The fabric installation method was also complex. The entire roof was fabricated in 2 pieces that were joined at ground level then the entire fabric was lifted onto a webbing net before being deployed along the length of the structure using a crane with a 30m long spreader bar.

Incredibly the installation process went smooth and as planned with the final result being a stunning long span tensile fabric structure.

Our client was very happy with the completed project, providing us with an excellent result on our customer satisfaction survey. The fabric install went amazingly, due to the field joint being completed on the ground, & the use of a spreader bar to lift & mount the fabric.

Our complete contracted package for this project was the design, supply & installation of HD bolts, steel structure, PVC membrane cover, and scoreboard over the outdoor pool.