Definition of a Term - How Important Is It?

I have represented various concrete and masonry materials used in restoration for over 40 years. If you have seen my business card then you know that it has the phrase "Think Concrete" in the upper right hand corner. I say this as even today many people don't know the difference between Concrete and Cement and interchange the two all too often. That is why I wanted to clarify what FRCM stands for "Fiber Reinforced Cementitious Matrix". That being said there is now a further delineation needed due to the overall acceptance of the concept and what is currently available in the marketplace. If there is coarse aggregate in the FRCM then it would be "Fiber Reinforced Concrete Matrix", if there is no coarse aggregate it would be "Fiber Reinforced Cement Matrix", therefore both are FRCM's. There are currently two systems available, one a concrete system which is applied like a shotcrete the other a cement based trowel applied system. The two systems are quite different and are both a logical extension of the FRCM term however, like any other repair/strengthening material it is essential to review the properties of each product or system for the intended use.

For starters the "cement" product has an individual layer thickness of 6-8MM or less than .33 inches while the "concrete" system is typically up to an inch in thickness. Both are promising new technologies that have gained acceptance for our restoration/rehabilitation needs but differ greatly, in many cases, for their intended use. The concrete system is a very specific application of a modified Shotcrete while the cement system is based on a relatively new, less than 20 years, nano cement technology. The Shotcrete system requires a certified nozzle man to apply the material for both aesthetics and structural needs while the cement system can in most cased be applied by a mason who has experience with installing traditional stucco. The term Structural Stucco has been attached to the cement material for this very reason.

Each project, each application, requires the judicious review and design by a qualified structural engineer, taking into account the properties and attributes of both materials. As a typical distinction consider that the concrete system may prove more appropriate in concrete applications while the cement system more appropriate in masonry applications. Many properties such as breathability, thickness. ease of application, application force and more need to be taken into account.

As a last statement, "If you have considered, or are using/specifying traditional resin based FRP systems you owe it to yourself and your client to consider these promising alternatives! The Class A Fire Rating alone should prompt more consideration especially for internal strengthening opportunities.