The American Concrete Institute (ACI) is a non-profit organization devoted to all matters related to concrete. Their extensive documentation and educational programs have made them the go-to resource for the industry. Recently, ACI published a new report on chemical admixtures for concrete called ACI 212.3R-10. This document contains a new chapter (15) focused entirely on Permeability Reducing Admixtures (PRAs). For those of us in the concrete waterproofing business, Chapter 15 has us very excited!

Prior to the new Chapter 15, permeability-reducing admixtures were mentioned only in passing as waterproofers or damp proofers – tucked away within a no-man’s-land chapter entitled Miscellaneous. Today, this specific category of admixtures has its own chapter, which is an assimilation of an enormous body of work. The chapter finally dispenses with troublesome terms like waterproof and damp proof. It explains (finally) that not all PRAs are created equal and discusses the three primary categories and how they function. The chapter discusses suitable applications for each type and provides a wealth of information on how to properly test and evaluate a PRA to ensure it's suitable for the intended use.

Perhaps the greatest value of the new chapter comes from its clear categorization of permeability-reducing admixtures into two divisions: Permeability Reducing Admixtures for Hydrostatic(PRAH) conditions and Permeability Reducing Admixtures for Non-Hydrostatic(PRAN) conditions. The difference between the two is simple and straightforward. At last we have clear and descriptive language to use when speaking about these special types of chemical admixtures.

Chapter 15 embodies research dating back nearly five years. Volunteers from across the industry spent countless hours and untold effort in its development. The result is an excellent and valuable document. Congratulations ACI and good on you!

Read it HERE