Technicoat International Factory (TeknCoat) of the UAE, a specialist in the field of insulation, waterproofing and protection of sub-structures, says its range of protective coatings can be put to good use in foundation engineering applications.

"We have been extending the scope of application for our products steadily and we now provide effective solutions to almost all types of problems faced by construction industry in the areas of insulation, waterproofing and energy saving, backed by a 10-year guarantee on our range," says Hathem Al Sayegh, the managing director of the Dubai-based firm. "As a further extension to these areas, TeknCoat can now provide protective coatings for pile foundations and pile caps."

He continues: "The use of pile foundations for structures is favoured in the Middle East due to the region's sandy soil conditions, but these piles need to be protected and waterproofed during the construction stage and this is where TeknCoat products can be put to good use."

Detailing the process, he says: "In normal shoring practices, contiguous surfaces are sand-blasted and made dust-free followed by the application of gunite to obtain an even surface. The surface is allowed to cure for three to four days and on completion of the curing, it is allowed to dry. At this stage, a range of TeknCoat products - V11S, R1, R2 and a geotextile - can be used to effectively waterproof the pile heads.

"V11S is a two-component, cementitious waterproofing material, providing excellent water and salt resistance. It comes in a pack of dry mix and liquid mix. Prior to the application, a homogenous mixture is prepared on site using a mechanical device. The surface of the pile caps to be treated is cleaned and the V11S mix is applied uniformly using a special roller. After the first coat is cured, a further two coats of V11S are applied in succession, after curing, and the pile head is then is allowed to cure completely for six hours.

"A protective coating of TeknR1, single-component polyurethane, acting as a primer of TeknR2, is applied over the coated surface. This coat has excellent properties and is capable of penetrating the concrete surface and filling up any cracks. After three hours of drying, TeknR2 - which acts as a secondary coat to TeknR1 - is applied and allowed to cure for five hours.

"Follow-on construction work can then proceed after certification by a TeknCoat engineer. Any damages suffered during the fixing of reinforcements should be rectified using the same materials and process.'

TeknCoat can provide additional protection to pile caps which are built below the water table, through the use of a geotextile with R2, in addition to the standard waterproofing procedure. Under this procedure, after the application of three coats of V11S and Tekn R1 and Tekn R2, a layer of Fybex is fixed while the coat is still tacky and allowed to cure for five hours. A final coat of TeknR2 is then applied and allowed to cure for eight hours. After this, some protective work may be necessary to prevent any further damage."