Putting the Mental in Fundamental
Tales From The Concrete Bungle
If you ever struggled to understand the concept of sunk cost fallacy, there was a harrowing documentary about it last night on CNN called ‘The Presidential Debate.’ I’m packing for Scotland, and I know they’ll have questions. We request that you respect America’s privacy during this difficult time.
In more exciting news, I wrote an academic paper about concrete this week. I asked my 14-year-old son to read it before I submitted it, and he said, “It actually wasn’t boring.” For those of you who have never raised children, that’s an A+.
I was a little disappointed that it was not a formal essay. If it had been, I could say I’d written a concrete abstract. It’s the little things.
The most enjoyable aspect of this class is reading Mark Miodownik’s bestselling book about materials, Stuff Matters. Having written several papers about materials this semester, including a paper about paper, I have enormous respect for a materials scientist who can write a New York Times bestseller about steel, glass, ceramics, and the other mundane materials we rely on every day. Miodownik even turned me onto a whole branch of science that I was unaware of — psychophysics. Psychophysicists study the relationship we have with materials, such as how the crinkle of a chip bag affects our experience of eating them, why we still prefer ceramic plates to less expensive or more durable materials, or how to create novel materials that sufficiently mimic the more environmentally costly things we have a hard time parting with.
If you enjoy nonfiction writers like Mary Roach and Michael Pollan, I think you’ll enjoy Stuff Matters by Mark Miodownik. Anyway, I’ve warned you. This is literally an essay about concrete.
Chapter III of Stuff Matters by Mark Miodownik, a summary
Concrete is a nearly perfect construction material, a liquid that can be poured into any form and then allowed to harden until it can serve quite literally as a bomb shelter. It is so common and essential to modern construction that it is hard to imagine a city without it. Even in suburbs and rural areas, the foundations of stud-frame houses and barns are dug and filled with poured concrete or built up with concrete blocks separated and bound together with mortar —another concrete variation. Though we are discovering the environmental risk associated with the global reliance on concrete, it is difficult, if not impossible, to replace this unique and ancient medium. This may be why the third chapter of Mark Miodownik’s bestselling book, Stuff Matters, is called ‘Fundamental’ (Miodownik, 2013).
A variable composite material, concrete is composed of inexpensive components such as sand, gravel, crushed stone, and water, and the properties of its various species depend on the proportions and types of those constituents. However, the crucial ingredient that takes concrete from slurry to stone is cement, a superheated mixture of limestone and clay — or any other source of calcium carbonate and silicate minerals. When water is added to cement, the new calcium silicate hydrate compound forms crystal-like structures that bind to themselves, the aggregate materials in the concrete mixture, and other materials such as steel reinforcing bars (Miodownik, 2013). In a slow transformation that can seem almost magical, the liquid cement becomes a gel, then a paste, and finally hardens into a stone. This chemical reaction, known as hydration, locks the water molecules into the structure, counterintuitively producing a solid, waterproof material (Mehta et al., 2014).
Ancient Romans developed concrete as a building material around 300 BCE (Jackson et al., 2014). Roman concrete, or opus caementicium, was made from lime mortar, water, and volcanic ash. Serendipitously, a nearby volcano provided the high temperatures required by the cement-making process; it would have been difficult for the Romans to generate cement furnaces on the scale for which they utilized concrete construction. As it was, Roman builders scooped up the ready-made cement ash outside of Naples and transported it wherever they needed it (Miodownik, 2013). This material was used extensively to construct now-iconic buildings such as the Pantheon and the Colosseum, which still stand today (Jackson et al., 2017). Concrete’s ability to set underwater lent its application to the Roman Empire’s famous and unprecedented bridges and aqueducts.
Unfortunately, even the Romans were limited to using concrete for its compressive strength — the ability to withstand heavy downward pressures that far exceeded other materials of the time (Miodownik, 2013). Without an arch or dome shape to distribute the load downward, concrete is weak in tension, requiring reinforcement for flat beams and spans (Neville, 2011). However, in the 19th century, a French gardener named Joseph Monier made an unintended advancement in construction technology, embedding loops of steel into concrete plant pots and, “as luck would have it, steel and concrete have almost ideal coefficients of expansion” (Miodownik, 2013, p. 62). This reinforced concrete combined the compressive strength of concrete with the tensile strength of steel, creating a long-lasting combination that can be seen in “literally half the world’s structures” (Miodownik, 2013, p. 66).
Despite its simplicity and ease of manufacture, careful attention must be paid to the quality of concrete construction. In 2010, a magnitude 7.0 earthquake caused widespread devastation and loss of life in Haiti, highlighting the vulnerabilities of poorly constructed concrete buildings (Miodownik, 2013). Many collapsed buildings were made with inferior concrete, absent proper reinforcement and quality control (DesRoches et al., 2011). The Haiti earthquake underscored the importance of using high-quality materials, proper concrete construction techniques, stringent building codes, and enforcement to ensure the safety and resilience of structures in earthquake-prone regions (Bilham, 2010).
Though we perceive classic Roman architecture as beautiful today, in the 20th Century, concrete construction came to be viewed as utilitarian and unsightly. Contemporary architecture has recently embraced concrete's aesthetic potential (Picon, 2003). Architects and designers now explore the material’s versatility as a medium for artistic expression, making the most of its various textures, finishes, and forms. The Brutalist buildings of the mid-20th century and other modern minimalist designs pushed back against the nostalgia of earlier architecture and made the most of concrete's novel attributes (Giedion, 1941). Techniques such as exposed concrete, polished surfaces, and colored concrete have expanded the possibilities for its use in interior and exterior design (Forty, 2012). This new philosophy emphasizes concrete’s inherent qualities, creating a sense of authenticity and connection to the human effort of construction.
The latest development in concrete is in partnership with other living beings — bacteria. In the search for even more durable materials for remote locations, scientists have incorporated starch and bacteria into the composition, producing an aggregate that heals itself. When cracks appear, as they invariably do, the extremophilic bacteria are hydrated, eat the starches, and produce calcite that fills the cracks (Miodownik, 2013). “Research now shows that cracked concrete that has been prepared in this way can recover 90 percent of its strength thanks to these bacteria” (Miodownik, 2013, p. 68).
Nevertheless, concrete also has a dark side. Concrete accounts for 60% of all carbon emissions in fast-growing cities like Hong Kong (Zhang et al., 2022). Ironically, increased carbon dioxide levels damage the protective layer around inner steel structures and accelerate the deterioration of reinforced concrete, shortening the lifespan of bridges, dams, buildings, and other structures we rely on daily (Hassan & Amleh, 2024). These facts, taken together, reveal an insidious cycle that governments and engineers worldwide must address if we are to continue using concrete as our fundamental urban building material.
Concrete's material properties, historical significance, and evolving aesthetic qualities contribute to its perseverance in construction and architecture across millennia. With the public shift in perception from concrete as a purely practical material to one with significant aesthetic potential, architects and designers continue to explore innovative ways to utilize concrete, showcasing its versatility and beauty. If we can address its environmental cost, there may be no end to humanity's relationship with concrete, the most fundamental building material in our modern world.
Works Cited
Bilham, R. (2010). Lessons from the Haiti earthquake. Nature, 463(7283), 878-879.
DesRoches, R., Comerio, M., Eberhard, M., Mooney, W., & Rix, G. J. (2011). Overview of the 2010 Haiti earthquake. Earthquake Spectra, 27(S1), S1-S21.
Forty, A. (2012). Concrete and culture: A material history. Reaktion Books.
Giedion, S. (1941). Space, time and architecture: The growth of a new tradition. Harvard University Press.
Hassan, M., & Amleh, L. (2024). Influence of climate change on probability of carbonation-induced corrosion initiation. Periodica Polytechnica.Civil Engineering, 68(1), 57-67. doi:https://doi.org/10.3311/PPci.22101
Jackson, M. D., Mulcahy, S. R., Chen, H., Yao, L., Li, Q., Cappelletti, P., & Wenk, H. (2017). Phillipsite and al-tobermorite mineral cements produced through low-temperature water-rock reactions in roman marine concrete. The American Mineralogist, 102(7), 1435-1450. doi:https://doi.org/10.2138/am-2017-5993CCBY
Mehta, P. Kumar, and Paulo J. M. Monteiro. 2014. Concrete: Microstructure, Properties, and Materials. 4th ed. New York: McGraw-Hill Education
Miodownik, M. (2013). Stuff matters: Exploring the marvelous materials that shape our man-made world.Mariner. DOI:10.1016/j.mattod.2013.10.016
Neville, A. M. (2011). Properties of concrete. Pearson Education Limited.
Picon, A. (2003). Anxious landscapes: From the ruin to rust. Grey Room, 1-25.
Zhang, Y., Pan, W., & Teng, Y. (2022/11//). Reducing embodied carbon emissions of concrete modules in high-rise buildings through structural design optimisation. IOP Conference Series.Earth and Environmental Science, 1101(2), 022023. doi:https://doi.org/10.1088/1755-1315/1101/2/022023
Once, when in love, I rambled on about concrete for an entire evening wanting to woo her with what I found to be such valuable and essential information. As with everything else, I have since forgotten so much more than I now know, but I recall the glint in her eyes being amused by my behavior, and that I knew enough off the top of my head to go on for over an hour with everything from Roman Aqueduct concrete materials combining salt water with cement to the Hoover Dam still not being completely cured, to strengths of concrete typically used and the applications in current building construction, to the fire proofing aspects, to the finishing and embedding of structural fiber, steel, mesh, to the additives that allow curing in freezing temperatures but rapidly decay iron, to the coloring and polishing, to the solar energy mass heat storage, to the plumbed hot water heated and electric resistance heated slabs, to mortars… Yes, Jonathan, why don’t we use our volcanos for their energy every day to process cement, or anything else? Hmm. Seems we could figure something out by now. :). Safe and lovely travels!
Not boring. Me, three.