Sika AG to be the saving grace for a Victorian-era tourist attraction’s roof

Brighton’s SeaLife Centre’s ageing roof panels replenished with Sikacem-133 Gunite mortar

Sika AG, a leading German conglomerate actively involved in the Polymer Concrete Market, announced in 2016 that it had been chosen to provide a Total Corrosion Management and long-term concrete repair solution to enhance the roof structure of the world’s oldest aquarium and restore it to its full Victorian-era splendour for posterity. Sikacem®-133 Gunite was selected as a strong, cement-based repair mortar to replace the deteriorating concrete soffits that are part of the roof at the iconic SeaLife Centre in Brighton, England. With repair work underway in the vicinity of the marine tanks, the venture needed dedicated management effort and coordination between the structural engineers Gyoury Self Partnership and the main contractors Barwin to make sure that the repairs did not harm the marine life in any way.

Structural surveys conducted showed an area of approx. 1200m2 of the nearly 200-year-old, Grade II-listed SeaLife Centre’s soffits had suffered from sustained chloride contamination, increasing the danger of concrete delaminating from the rooftop. When the issue intensified as a result of cracks observed in the limestone branding of the connecting columns, the main contractor needed a large volume, high-quality concrete repair solution to strengthen the failing soffits and avoid any additional damage. The solution that seemed best suited to tackle this pressing challenge was Sikacem®-133 Gunite. Barwin has gotten rid of the contaminated soffits as a part of the repair work that been underway in several phases since 2011. The soffits have been strengthened with Sikacem®-133 Gunite, a fibre reinforced micro repair concrete modified with a polymer. The concrete was hand-finished with the help of a trowel and dry-spray applied to ensure an even finish for the purpose of an attractive protective coating.

To manage the structure steel corrosion, products from across the range of Sika’s TCM portfolio were used. Sika® FerroGard®-903+, a multi-purpose liquid corrosion inhibitor applied on the surface was utilised. After it is applied to any concrete surface, the solution moves to the reinforcement within the concrete and creates a protective layer that subdues any present corrosion and it even prevents additional corrosion from occurring. In places where the chloride was high, Sika® Galvashield® anodes were deployed to prevent new corrosion sites from forming together to the restored concrete. This unique yet simple anode system comprises a small, circular shell around a zinc core that is readily fastened to steel reinforcement that may be exposed. After it is installed, the zinc core corrodes in a sacrificial manner to the adjacent rebar, thereby protecting it. The last solution used was Sikagard®-675W ElastoColor i.e. an anti-carbonation coating with superb vapour resistance, ageing, and chalking.

A combination of TCM, coating systems, and Sika’s concrete repair can be the perfect solution for all reinforced concrete structures with a guarantee of up to 20 years. Wayne Sampson, Barwin Director stated that it was an honour to be selected to replenish the iconic landmark at Brighton. The Sika solution should be able to make the reinstated soffits stand tall for years to come. The system is not only incredibly effective but is also extremely simple to deploy. The Director is of the view that such a prestigious project needed the best solution and Sika was deemed the most worthy. It is expected that the refurbishment of the SeaLife Centre should draw thousands of additional visitors to the aquarium every year. The proven solutions of Sika will go a long way in safeguarding Brighton’s crown jewel from long-term chemical corrosion and it should be able to shine brightly well into the middle of the 21^st century.