Company Announcement - A special self-levelling silicone joint sealant supplied by a.b.e. Construction Chemicals was specified for the repair of the ‘Delta’ apron at O.R. Tambo International Airport in Johannesburg. a.b.e. Construction Chemicals is part of the Chryso Southern Africa Group. Samantha Ferreira, Sales & Segment Manager: Silicones, Sealants & Specialist Adhesives, says Dow Corning 890 SL self-levelling joint sealant was applied to several thousand linear metres of damaged joints on the busy OR Tambo apron by concrete repair and refurbishment specialists, MBR.

“Dow Corning 890 SL sealant’s self-levelling characteristics make it ideal for sealing irregularly shaped joints and cracks by providing adequate adhesion to the interfaces, without the need for tooling. The sealant can withstand the joint opening to twice its width and closing to half its width, without adhesion loss. It requires no primer to bond to both concrete and asphalt. The sealant provides outstanding long- term performance in airport, bridge or highway joints in which extreme movement occurs. It is also jet fuel resistant, an important factor for this OR Tambo apron project,” Ferreira adds.

Unlike organic sealants, Dow Corning 890 SL silicone rubber is virtually unaffected by sunlight, rain, frost, ozone or temperature extremes. “Most organic sealants stiffen in cold temperatures and soften in hot weather. Organics can furthermore degrade and crack, particularly in the Highveld’s searing heat. Dow Corning 890 SL is also easy to apply. It is a one-component sealant that is cold-applied, directly from a bulk container into the joint, either by hand or air-powered pump – and it has an exceptionally fast curing rate,” Ferreira adds.

Dow Corning 890 SL sealant has in recent years been extensively used for airport joint repairs including airports such as King Shaka International Airport in Durban, Sir Seretse Khama International Airport in Gaborone, King Mswati 111 International Airport in Swaziland, Polokwane Airport, and Fireblade Aviation’s VIP charter flight section at O.R. Tambo.
“The sealant has also been widely applied for repairing joints in concrete roads,” Ferreira states.
Applicator, MBR, is a Dow Corning Specialist-approved Quality Bond member. Dow Corning’s Quality Bond system ensures that all Quality Bond members are fully trained and certified annually. As a specialist-approved Quality Bond member, MBR’s application of Dow Corning sealants carry a 5-year labour warranty, while the joint sealant itself has a 15-year crack, craze crumble warranty issued by Dow Corning.