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Thwarting Concrete Deterioration with Integral Crystalline Waterproofing

Concrete is the most used man—made material in the world. In fact, it is used twice as much as the total of all other building material in the world, including wood, steel, plastic and aluminum. To extend this a bit further; nearly 3000 kg ‘s of concrete is used annually for each man, woman and child across the globe. Concrete’s importance cannot be understated. It is used so much because of its formability and compressive strength. As is seen from the landscape of most of the major cities across the world, concrete is the back bone of the construction industry Concrete is also a durable material with the ability to sustain a long structure life. However there is extensive evidence throughout the world that deterioration of concrete, requiring repairs and even reconstruction is occurring at a high rate throughout the world.

According to the Portland Cement Association, concrete durability is:  the ability of concrete to resist weather action, chemical attack while maintaining its desired engineering properties? Concrete is durable; yet, there is extensive evidence to show that concrete structures the world over are not meeting their designed service life due to rapid deterioration. Concrete  can deteriorate under certain circumstances, such as:

• Chloride attack/Corrosion of steel reinforcement
• Sulfate attack
• Alkali Aggregate Reaction (AAR)
• Freeze/thaw cycles

However: with the exception of the damaging factors listed above, all the adverse influence on concrete durability involves the transport of fluids through the concrete. As per Michael T. Kupal’s, ‘Construction waterproofing handbook’, water continues to damage or completely destroy more buildings and structures than war or natural disasters. Cracks in concrete generally interconnect flow paths and increase concrete permeability. Thus, a waterproofing measure is needed to avoid costly repairs caused by water infiltration. Several studies indicate that decision-makers on a global level need to be forward thinking and willing to implement long-term strategies which will save millions of dollars in repair costs down the road. This revelation has focused attention on proven permanent concrete waterproofing technology— integral crystalline waterproofing.

 

Integral crystalline waterproofing

The basic idea behind crystalline waterproofing is to prevent the movement of water by plugging or blocking the natural pores, capillaries, and cracks present in concrete. Over the service life of the structure, concrete without any admixture is expected to develop micro cracks that may develop into macro cracks. These cracks will allow free passage to moisture, which causes major structural repair work. However when crystalline technology is used, the passive admixture in the matrix gets activated as soon as it comes in contact with moisture in the pores and micro cracks of concrete. On activation, this admixture starts crystallization and develops a microstructure that is needle like (crystals) in concrete.

Benefits cf ICW

• Less Repair, meaning less overall cost;
• Saves weeks on the construction schedule by replacing the external waterproofing barrier;
• It is a permanent solution — becomes part of the concrete so it won’t wear away or crack; and
• Concrete remains recyclable at end of life.

The addition of the ICW self-sealing water protection system transforms concrete into a powerful water-resistant barrier. The crystalline technology turns porous concrete into an impermeable barrier The result is a structure with reduced cracking, self-sealing and waterproofing abilities that provide a powerful defense against water damage and corrosion of reinforcing steel. These attributes lead a concrete structure to being more durable, and are able to withstand tear and decay throughout its service life.

Furthermore, the most recent version of the American Concrete institute’s ACI 212.3R—lO: Report on Chemical Admixtures for Concrete devoted a new chapter (Chapter 15) to Permeability Reducing Admixtures (PRA) which defines new PRAH and PRAN classifications.

• PRAN — Permeability Reducing Admixture for Non-Hydrostatic Conditions
• PRAH — Permeability Reducing Admixture for Hydrostatic Conditions

Kryton International Inc.’s Krystol Internal Membrane or KIM is the only admixture that demonstrates the performance of a hydrophilic crystalline, PRAH. KIM provides the highest level of water resistance, self-sealing and field-proven longevity, which proves its effectiveness as a PRAH.

Fadi Fahat
Territory Manager; Middle East
Kryton International Inc.
E-mail: ffahat@kryton.com
Web: www.kryton.com

Source: Arab Construction World