Concrete treatment in 1, 2 . . . 10

by Tania Wannenburg

Several rehabilitation products from Sika were used in the facelift of 9 Dorp Street in Cape Town, a significant architectural site earmarked for heritage status.

Ten Sika products were used for the renovation and repair of 9 Dorp Street, one of the most renowned modernist buildings with considerable architectural significance in Cape Town.

Concrete spalling
To repair spalling, SikaTop Armatec-110 EpoCem was applied as a bonding primer and reinforcement corrosion protection. Sika MonoTop-610, a cementitious, polymer-modified bonding slurry with active corrosion inhibitors, was used as primer prior to the application of Sika MonoTop-615 HB, a polymer-modified repair and reprofiling mortar. Heritage architects tested numerous samples to obtain the closest possible colour match to the existing concrete.

A fluid grout that expands whilst curing and provides high strength, the cement-based SikaGrout-212, completed the spalling repairs.

Structural strengthening
For passivation of the reinforcing steel, Sika FerroGard-903+, a migratory corrosion inhibitor (MCI), was applied to all repaired concrete surfaces, while Sika CarboDur Plates, consisting of carbon fibre reinforced polymer (CFRP), was bonded onto the building as external reinforcement.

To form a barrier against water infiltration and to structurally bond concrete sections together, Sikadur-52 ZA was used as a high-strength injection resin to fill and seal voids and cracks in the concrete. In addition, Sikadur-31 DW, based on a combination of epoxy resins and special fillers, was used as a thixotropic, structural two-part adhesive and repair mortar.

Sealing and waterproofing
Sikaflex AT-Facade, a moisture-curing elastic sealant, was used to seal all movement and connection joints, providing ultraviolet (UV) resistance, colour stability and ageing resistance.

Ideal for interior or exterior waterproofing and damp-proofing, SikaTop Seal-107 was applied to protect the structural concrete against the ingress of contaminants, control moisture and increase the resistivity.

Tel: 031 792 6500
Website: www.sika.co.za

You may also like