Nov 23 2010
The various methods of protecting concrete are explored by Joseph Nabih, Technical Manager, Sika Gulf at MEED's Middle East Roads, Bridges and Tunnels conference today at Westin Hotel, Dubai.
He highlighted various challenges and solutions for concrete protection with a focus on Hydrophobic Impregnations. Hydrophobic Impregnation is a proven concrete protection technology that prevents water ingress into concrete structures thus decreasing the likelihood of degradation due to aggressive influences.
This technique can be used for both new and existing concrete structures. It is an established fact that damage to concrete always involves water. Water acts as a vehicle for transporting aggressive substances, such as chloride ions which are present in the water as it is drawn into the concrete by capillary action. Water also serves as a reaction medium and a reagent in destructive chemical processes, foremost among these being the corrosion of the reinforcing steel. Corrosion leads to the deterioration of overlying concrete, and exposes the reinforcing steel. Clearly, one of the most efficient ways to protect concrete is to prevent it from absorbing water in the first place.
"Hydrophobic Impregnation has been used all over the world for many large scale projects like bridges, buildings, walls, silos and cooling towers, and other types on concrete structures," said Nabih. 3.2km Sitra causeway connecting Bahrain and Saudi Arabia is one of many bridges treated by Sika Hydrophobic Impregnation technology. "We prevented bridge from deteriorating and achieved the client requirement of 120 years of durability design life," he added.
Sika has been at the forefront of concrete repair and protection technology since the 1920s. Sika pioneered the development of concrete repair products and systems from the early beginnings, with Sika Waterproof mortars in the 1920s and 30s, through our development of epoxy and polymer latex modified repair mortars in the 1950s and 60s. In the 1970s Sika introduced the first "Complete Concrete Repair and Protection System" with Sika reinforcement primers, bonding bridges, repair mortars and leveling mortars plus protective impregnations and coatings.
Source: http://www.sika.com