"Green Concrete", Chasing Our Tails - When Green Isn't Green (enough).

I have been reading several articles, research studies and claims regarding various methods of attempting to make "greener" concrete.

As of this writing, I am decidedly underwhelmed by most of the claims and research studies and to be blunt, aghast at the amount of wasted time, resources and money trying to make a "greener" concrete, with a lower "carbon footprint".

Lots of posturing and claims with very little substance.

In the Meantime

Even before the current and increasing pressure to create "green concrete", back in March of 2000, a colleague of mine and renown Petrographer and Professor at Texas A&M (Dr. Shondeep Sarkar) introduced me to a technology called "Nano Colloidal Silica".

Even though I trusted his opinions, he knew that no matter how promising a technology may be, my first impulse after getting interested and before getting overly excited; I would try to find what was wrong with whatever it was I found interesting.

Early in my career way too many times as I relied on the input of others without fully investigating something, I would later be embarrassed that something presented, by people I felt were reliable turned out differently, and usually NOT in a favorable way, than what was represented.

This is also when I discovered what has become a "normal" trend of shifting narratives and/or revisionist history began to replace the original idea, concept, methodology or product.

Those experiences led to me becoming the skeptical curmudgeon I am today!

Green and Sustainable

The terms green and sustainable are bandied about so often that along with terms such as "game changer", such terms have become nearly meaningless and trite.

When an existing product CAN be dramatically improved, particularly its life expectancy and durability, THAT is not only the least path of resistance for creating true sustainability and what SHOULD be considered green; such efforts are too often ignored in deference to the "shiny object" allure of exotic sounding and well promoted efforts that generally are nowhere near as effective as the existing technology, or as presented, but DO have the "whiz-bang" sexiness that attracts attention and the all important media support and FUNDING!

Nano Colloidal Silica - The Next Step, with a TON of caveats!

When Dr. Sarkar first got me involved with nano colloidal silica back in March 2000, he had conducted some very impressive tests in his laboratory. Enough for me to ask for samples of the product he used.

As I experimented with the product, I found inherent issues that unless addressed proactively, would limit the practical viability of this technology.

The deeper I dove, the more I realized why this technology hadn't taken off like one would expect. There was/is a dizzyingly and confusing number of choices available from various manufacturers of colloidal silica (even more so now), along with particle shapes, sizes, origination, processing and modifications that could improve or optimize the use of a colloidal silica for various end uses and for product modification of other materials and products.

Practical, Impractical and What the H?

Most colloidal silica can be subject to compromise before these are even used.

Temperature changes, sunlight exposure and a host of other environmental issues can compromise or even remove the beneficial properties of a colloidal silica without anyone being the wiser.

Most of the formulators I spoke with, were unaware of several environmental issues that are inherent with colloidal silica.

With regards to concrete, the various sizes and shapes of the colloidal silica can create a significant variation in performance. In most instances, there was always at least SOME benefit, but unless the formulary is corrected, the benefits may be only modestly incremental and likely not worth the extra expense, all the way to creating a Portland Cement-based concrete that can have 3-4 times the durability of even an ultra high performance concrete. NOTE: Virtually every other alternative to colloidal silica, when used improperly, or does not function as intended is deleterious to concrete.

If you compare a properly functional nano colloidal silica with the heavily promoted PLC/Type IL Cement, its no contest, not even close.

At best, a PLC/Type IL Cement concrete "can" reduce the carbon footprint by 8-12%, which ASSUMES equal durability to standard Portland Cement Type I/II, which has NOT proven to be the case.

Compare the optimized claims of PLC/Type IL Cement against a properly formulated nano colloidal silica, which can increase the durability of a standard Portland Cement Type I/II cement by a factor of 3-4x's or potentially even longer; just think, even a 25% improvement would be more than double the optimistic numbers assigned to PLC/Type IL Cement.

That is an inherent 25% reduction in CO2 when weighted for improved durability.

In my view, a properly formulated nano colloidal silica will create a 300% - 400% reduction in CO2 emissions when weighted against its life expectancy! NOTE: This doesn't even include the "wildcard" of labor, material and environmental issues created by repair and replacement costs.

Truncated Data - Undermining True Progress

In WAY too many research papers, studies and tests, truncated data is used as a "final" evaluation of efficacy, which is at best misleading, and at worst, creates more problems than it solves.

There are two axioms that are consistently ignored in study after study, research after research, and that is: "For EVERY action, there is an equal and opposite REACTION".

In WAY too many of these studies, research papers and tests, we are shown the action, but seldom, if ever are we shown the REACTION! This exists whether the study, research or testing covers these or not.

I do not recall ANY study within the past 50 years where reactions were noted or even mentioned. THAT is a travesty....it is understandable why this is routinely ignored since the exploration of reactions can increase the length of study by several orders of magnitude. Understandable, but unacceptable!

The other, closely linked to action/reaction is "Cause and Effect", which can be even MORE daunting since such studies can become multi-generational before cause and effect is mostly understood. I didn't say COMPLETELY understood, since that goal is virtually unachievable. NOTE: The exact mechanism of cement formation remains incompletely understood.

Thankfully we don't need to fully understand something to realize and utilize when something is truly beneficial. This is why so many inventions are discovered by accident rather than intent.

Truncated Data and Fall Out

In ALL professions and industries, there are periods where a widely adopted "shiny new object" can become a major embarrassment at a later date, even though the majority of experts at the time fully endorsed whatever the shiny new object was.

Simply watch TV for any length of time and you will see advertisements for the shiny new object of an advertised medication or drug.

In the past, it took a torturous amount of time for most drugs, medications and food additives to be approved. This changed back in the 1980's when a successful effort was mounted to streamline the approval process, where in the past, a product had to prove it wasn't harmful..today unless proven to BE harmful, it can be approved. NOTE: Many advertised drugs, medications, etc. are now the subject of major lawsuits since the reaction portion of research is, for all intents and purposes, no longer a requirement.

Since the year 2000, a full one third of ALL medications and drugs approved by the FDA have been removed, discontinued, relabeled or restricted because of latent issues that were NOT discovered or even discoverable within the now truncated process of FDA approval. It takes an average of 4.2 years in the public domain to BEGIN the determination of and reveal unforeseen issues.

In chemistry and household items, two examples of approved and "proven harmless" chemicals are now banned; DDT and PFAS.

I have avoided giving examples within construction and specifically concrete industries since I wanted the emphasis towards constructive progress rather than dig up old and sensitive issues.

Indestructible Concrete?

When viewing the Parthenon and structures partially or completely immersed in the salty Mediterranean Sea, it becomes evident that even ancient technology made it possible to create concrete that is nearly indestructible.

Today, we have our own brand of creating indestructible concrete, we simply need to get moving and stop looking outside of what we already have. Sometimes the simplest solution is the best.