Five AESS Categories

The Walters Group head office in Hamilton, Ontario, received an exciting upgrade in 2018. The new look involved a rugged exterior to tie in the old industrial roots that were first formed in 1956. The minimalist interior showcases the strength and versatility of steel, which is the structural solution of choice, with AESS category 1 structural steel and cold-formed steel in the floor and roof supports.

The Tim Hortons Field was completed in 2013 and contains AESS category 1 throughout the 22,500-seat stadium. Over 10,000 assemblies of steel were used, many of which are featured in publicly viewable areas. Walters Group’s fabrication team prepared the steel surface using SSPC-SP6 commercial blast cleaning. Then, a three-coat paint system was used, two of which were shop-applied and the final applied onsite.

The giant inclined columns are a part of the Ontario College of Art and Design’s (OCAD) one-of-a-kind lateral system and are category 2 AESS. Walters Group used a highly integrated design approach, with our team taking on the design assist, fabrication and erection of the slanted lateral pipes. There were high levels of planning to choreograph the execution of the AESS steel to ensure an efficient and smooth installation.

The Joyce Centre for Partnership and Innovation located at Mohawk College contains category 2 AESS support branches. The straightness tolerances of these members were not to exceed ½ if the standard camber and sweep tolerance specified in the specifications.

All exposed edges of steel plates were milled or flame cut, exposed welds were ground smooth and finished flush and welds were ground that were within the reach of the public.

The giant AESS branch features are fully exposed to add a beautiful design and teaching potential, with customized beam-to-column connections.

Home to the Saskatchewan Roughriders, the Mosaic Stadium at Taylor Field contains a complex category 2 AESS steel roofing system.

With almost no 90-degree angles and extremely intricate connection nodes, this was a big challenge for Walters Group. Our team of engineers created a computerized model to simulate the structural stress that would be created, then perfected the curvilinear shape of the exposed steel roof to take into account high tolerances and intricate joint construction.

Walters Group provided a full range of services, including design-assist, value engineering, connection design, detailing, supply and erection of 5,200 tons of AESS with predominantly non-regularly curved geometry.

Fabrication of the exposed steel was performed with special care and necessary straightening to maintain the condition of the material, with tight tolerances for setting the embedded items on the erection drawing. All shop and field assembly was done by welding with ground bevel welds resulting in smooth, well-made corners.

Six AESS pipes with tapered tops support the pavilion’s network of cables and fabrics. Hidden beneath is a smart steel foundation system that was only backfilled rather than cast within concrete.

Walters Group was responsible for the detailing, engineering, fabrication and installation of the steel and cables with fabric. The clients wanted this to be a feature element, and AESS category 3 was selected. The steel was cleaned, the field joints were bolted or pinned, steel edges were ground, welds sealed, and the tolerances were twice as stringent.

During transportation and erection, the AESS had to be protected to prevent damage to the coating, with even the smallest damages to be repaired to be nearly invisible.

Twenty VivaNext shelters were fabricated and erected in the rapidly expanding York Region. The shelters are a high-end steel structure, predominately non-regularly curved geometry and were built using the specialized expertise of Walters Group’s very own Feature Walters.

Each of these structures were made of three segments of AESS, joined harmoniously so that the component parts would invisibly meld into a unified whole, thereby hiding the connections. The connections were completed by the Walters Group’s welding robot to make the joints precise, consistent and imperceptible to commuters.

The paint quality was selected to be an automotive grade external paint with a 25-year warranty to minimize the maintenance costs of upkeep to the paint and appearance.

Located in Downtown Toronto, the Approaching Red Sculpture is a grand example of Walters Group’s experience with AESS 4.

Comprising of two cured sheets of steel, the aesthetically pleasing sculpture was painted a bright automotive paint with all types of imperfections carefully removed. Days were spent priming and sanding, as AESS 4 characteristics highlight the importance of complete smoothness regarding finish.

Walters worked closely with the architect to ensure we matched their vision and offered AESS advice along the way to ensure the vision became a reality. Walters machined, painted and erected the structures, while also utilizing new approaches to hide bolted connections to maintain AESS category 4 integrity.

The West Block Rehabilitation Project in Ottawa required supplying and installing AESS fabricated to look like trees.

The tapered AESS branches are held together with hidden bolted connections, and tight tolerance issues had to be resolved before installation could even begin. The exposed welds were given a smooth, flush look, free from any defects.

Walters Group performed our highest calibre of architectural metalwork possible, with joints welded, ground and polished to be indistinguishable in finished work. With 1,100 tons of AESS and encased steel, 3D software was used to identify and resolve potential interferences while also indicating where conduits could run up the trunks of the steel tree and branches.