FACT: The term “Crystalline Admixture” is broad, and can cover a wide range of products with completely different characteristics. Your concrete waterproofing decision should take into account the particular product’s performance history through accurate, third-party long-term testing.

Though a concrete waterproofing product may be specified for a project, it is not necessarily the best product for the job. Many specifications are made due to past experience with a similar job, or perhaps the Specifier simply did not know of a better option. As the concrete waterproofing industry continues to evolve rapidly, research should be done even after a product appears on a Spec Package. This will ensure the project will be completed with products that work for the long term, and will ultimately protect the Project Manager’s reputation.

Long-term studies are the best research to review when comparing the results of products appearing similar to each other. Though they are performed less frequently than short term lab testing, the results of long term testing are ultimately more accurate.

Within the Crystalline Admixture category, the definition of what constitutes as a “Crystalline Admixture” is quite broad. Proper knowledge of what these types of products can do to benefit your structure is important when making the waterproofing decision for the concrete.

A long-term corrosion study was conducted by Joshua Ropert, MS and Ian N. Robertson. Ph.D., S.E., Professor from the University of Hawaii College of Engineering, for the Harbors Division of the Hawaii Department of Transportation.

The Harbors Division wanted the Engineering team to evaluate the durability of reinforced concrete specimens containing various pozzolans and chemical admixtures exposed to a marine environment.

Test panels were exposed in the tidal zone in Honolulu Harbor for a period of 9-10 years from 2002 to 2012. During exposure, the panels were monitored for half-cell potential, chloride concentrations, cracking and visible signs of corrosion.

Results:

• The panel produced using Kryton International’s Krystol Internal Membrane (KIM^®) at a dosage of 2% by weight of cement was one of the top performing panels. The KIM panel outperformed all other permeability reducing admixtures, and most of the corrosion inhibiting admixtures, with only high levels of calcium nitrite showing comparable performance. After 10 years of exposure, the KIM panel exhibited significantly lower half-cell readings than the control specimens. It also showed no signs of corrosion, even though panels produced with other admixtures or with a latex modifier exhibited inconsistent to poor results.
• Panels using the remaining admixtures, Rheocrete 222+, FerroGard 901, Xypex Admix C-2000 and a latex modifier exhibited inconsistent to poor results.

These findings are particularly relevant because they are based on field exposure in a harsh costal environment. This is the best type of testing because the exposure simulates the actual service conditions of a real structure. Laboratory tests are generally short term, and are designed to provide accelerated results using conditions that do not always model real life. Many products may perform well in a short term laboratory experiment, but perform poorly over the long term in real world conditions.

This report proves that KIM is effective at preventing corrosion over the long term under real world conditions. Of equal importance, KIM significantly outperformed other permeability reducing admixtures.

Taking the time to delve into the details of products, their companies, and the quality of testing and research that has been performed on them can save your project time, money, and potentially your reputation.