May 19, 2023
Commentary on Concrete
By Matt Childs, P.E.
Matt Childs Engineering PLLC
After water, concrete is the most widely used material for building structures above and below ground. Concrete is durable with many iconic structures lasting for centuries. The strength of concrete increases with time giving a high level of resilience to the forces of nature. Concrete is a sustainable product economically, socially, and environmentally. It is used to shape the cities and infrastructure of our time without placing an undue burden on future generations to maintain and rebuild when the design life of a structure has expired. Today’s standards expect concrete structures to have a service life of more than 100 years.
Cementitious materials have been used by civilizations over the past 5,000 years. The Egyptians used mud mixed with straw to bind dried bricks, and gypsum and lime mortars are evident in the pyramids. In the same period, 5,000 years ago, the Chinese used cementitious materials to bind bamboo in their boats and later rocks in portions of the Great Wall. These cementitious materials evolved with the advancement of science and technology to the concrete mixes of today.
There are milestones in the history of concrete [GL1] that should not go unnoticed. Between 300 BC and 479 CE the Romans used pozzolana cement from Pozzuoli, Italy near Mt. Vesuvius to build the Appian Way, Roman baths, the Coliseum and Pantheon in Rome, and the Pont du Gard aqueduct in south France. They used lime as a cementitious material. Pliny reported a mortar mixture of 1-part lime to 4 parts sand. Vitruvius reported a 2 parts pozzolana to 1-part lime. Animal fat, milk, and blood were used as admixtures (substances added to cement to increase the properties).
In 1818, Maurice St. Leger was issued patents for hydraulic cement, and Natural Cement (limestone that naturally has the appropriate amounts of clay) was produced in the USA. Six years later in 1824, Joseph Aspdin of England invented Portland cement by burning finely ground chalk with finely divided clay in a lime kiln until carbon dioxide was driven off. The sintered product was then ground and he called it Portland cement named after the high-quality building stones quarried at Portland, England. By1860 concrete mixes contained Portland cements of modern composition.
It was during the period between the turn of the century and 1840s that concrete pipe entered the American marketplace, and in 1867, Joseph Monier of France reinforced William Wand's (USA) flower pots with wire thereby ushering in the idea of iron reinforcing bars (rebar). In 1889, the first concrete reinforced bridge was built, quickly followed by concrete buildings and roads.
The 20th century was marked by concrete marvels including dams, bridges, skyscrapers, road networks, major underground drainage and collection systems. Concrete had found its place in America as the single most widely used construction material. Materials were standardized and specifications adopted for many applications of concrete mixes. But the story of concrete did not end there and continues to unfold.
In the 1980s, superplasticizers were introduced as admixtures and silica fume was introduced as a pozzolanic additive resulting in high strength concrete. By the end of the 1990s, a Swedish company introduced concrete polishing to the United States and now the technology is commonplace.
The story of concrete continues, of course into the 21st Century. Age-old Portland cement is now supplied as Portland-Limestone cement to reduce the carbon footprint of kilns and projects within the context of rules and regulations intended to mitigate the effects of climate change. Concrete products and structures such as buildings and bridge components can now be formed using 3D printers instead of centuries-old labor-intensive production and construction techniques. Scientists and manufactures of concrete products have introduced fibers into the concrete mix as an alternative to steel rebar and mesh. Transparent concrete (translucent concrete or light transmitting concrete) is achieved by replacing aggregates with transparent alternate materials to transmit light by using clear resins in the concrete mix. And researchers have developed a bendable concrete that may be stronger and more durable than regular concrete.
And this brings us to the characteristic of concrete that transcends time to the palaces of the Egyptian Pharaohs. Concrete is a durable material and when reinforced, can last for centuries in many of the Earth’s environments. Durability, or service life of a material is as equally important as its ability to perform intended structural functions. The capability of a structure to continue to perform satisfactorily for an acceptable period is a fundamental engineering consideration. It is exciting times for producers of precast concrete structures. History teaches us that it is a certainty that concrete will continue to be the world’s most widely used construction material. With assurance of demand for concrete and a little insight, manufacturers of precast concrete products can look at the history of concrete, the new concrete mixes entering the marketplace, along with advances in modern technology for construction to get a glimpse of new markets and applications for their products.
Matt Childs, Concrete Pipe News, Fall 2016, Commentary on Concrete, American Concrete Pipe Association
[GL1]Archive the History of Concrete in the appendix of the MCE website (you can either publish it on the site or leave it hidden). The use the link to the article/permalink and link it to the article by linking “history of concrete.”
The History of Concrete
Reactions between limestone and oil shale during spontaneous combustion occurred in the region now known as Israel to form a natural deposit of cement compounds. The deposits were characterized by Israeli geologists in the 1960s and 70s.
Used mud mixed with straw to bind dried bricks. They also used gypsum mortars and mortars of lime in the pyramids.
Used cementitious materials to hold bamboo together in their boats and in the Great Wall.
800 BC (Greeks, Crete & Cyprus)
Used lime mortars which were much harder than later Roman mortars.
300 BC (Babylonians & As Syrians)
Used bitumen to bind stones and bricks.
300 BC - 476 CE (Romans)
Used pozzolana cement from Pozzuoli, Italy near Mt. Vesuvius to build the Appian Way, Roman baths, the Coliseum and Pantheon in Rome, and the Pont du Gard aqueduct in south France. They used lime as a cementitious material. Pliny reported a mortar mixture of 1 part lime to 4 parts sand. Vitruvius reported a 2 parts pozzolana to 1 part lime. Animal fat, milk, and blood were used as admixtures (substances added to cement to increase the properties.) These structures exist today!
1200 - 1500 (The Middle Ages_
The quality of cementing materials deteriorated. The use of burning lime and pozzolan (admixture) was lost, but reintroduced in the 1300s.
Joseph Moxon wrote about a hidden fire in heated lime that appears upon the addition of water.
Bry Higgins was issued a patent for hydraulic cement (stucco) for exterior plastering use.
Bry Higgins published "Experiments and Observations Made with the View of Improving the Art of Composing and Applying Calcereous Cements and of Preparing Quicklime."
John Smeaton found that the calcination of limestone containing clay gave a lime which hardened under water (hydraulic lime). He used hydraulic lime to rebuild Eddystone Lighthouse in Cornwall, England which he had been commissioned to build in 1756, but had to first invent a material that would not be affected by water. He wrote a book about his work.
James Parker from England patented a natural hydraulic cement by calcining nodules of impure limestone containing clay, called Parker's Cement or Roman Cement.
In France, a similar Roman Cement process was used.
Edgar Dobbs received a patent for hydraulic mortars, stucco, and plaster, although they were of poor quality due to lack of kiln precautions.
Louis Vicat of France prepared artificial hydraulic lime by calcining synthetic mixtures of limestone and clay.
Maurice St. Leger was issued patents for hydraulic cement. Natural Cement was produced in the USA. Natural cement is limestone that naturally has the appropriate amounts of clay to make the same type of concrete as John Smeaton discovered.
1820 - 1821
John Tickell and Abraham Chambers were issued more hydraulic cement patents.
James Frost of England prepared artificial hydraulic lime like Vicat's and called it British Cement.
Joseph Aspdin of England invented Portland cement by burning finely ground chalk with finely divided clay in a lime kiln until carbon dioxide was driven off. The sintered product was then ground and he called it Portland cement named after the high quality building stones quarried at Portland, England.
I. K. Brunel is credited with the first engineering application of Portland cement, which was used to fill a breach in the Thames Tunnel.
The first production of lime and hydraulic cement took place in Canada.
The first systematic tests of tensile and compressive strength took place in Germany.
J. M. Mauder, Son & Co. were licensed to produce patented Portland cement.
Isaac Johnson claims to have burned the raw materials of Portland cement to clinkering temperatures.
Pettenkofer & Fuches performed the first accurate chemical analysis of Portland cement.
The beginning of the era of Portland cements of modern composition.
Blake Stonebreaker of England introduced the jaw breakers to crush clinkers.
Joseph Monier of France reinforced William Wand's (USA) flower pots with wire ushering in the idea of iron reinforcing bars (re-bar).
David Saylor was issued the first American patent for Portland cement. He showed the importance of true clinkering.
J. Grant of England show the importance of using the hardest and densest portions of the clinker. Key ingredients were being chemically analyzed.
The first rotary kiln was introduced in England to replace the vertical shaft kilns.
Henri Le Chatelier of France established oxide ratios to prepare the proper amount of lime to produce Portland cement. He named the components: Alite (tricalcium silicate), Belite (dicalcium silicate), and Celite (tetracalcium aluminoferrite). He proposed that hardening is caused by the formation of crystalline products of the reaction between cement and water.
The first concrete reinforced bridge is built.
The addition of gypsum when grinding clinker to act as a retardant to the setting of concrete was introduced in the USA. Vertical shaft kilns were replaced with rotary kilns and ball mills were used for grinding cement.
George Bartholomew placed the first concrete street in the USA in Bellefontaine, OH. It exists today!
William Michaelis claimed that hydrated metasilicates form a gelatinous mass (gel) that dehydrates over time to harden.
Basic cement tests were standardized.
The first concrete high rise was built in Cincinnati, OH.
Thomas Edison built cheap, cozy concrete houses in Union, NJ. They exist today!
Thomas Edison was issued a patent for rotary kilns.
Dr. Linus Pauling of the USA formulated a set of principles for the structures of complex silicates.
Air entraining agents were introduced to improve concrete's resistance to freeze/thaw damage.
The first major concrete dams, Hoover Dam and Grand Coulee Dam, were built. They exist today!
U.S. Congress annexed the Federal Interstate Highway Act.
First concrete domed sport structure, the Assembly Hall, was constructed at The University of Illinois, at Urbana-Champaign.
Fiber reinforcement in concrete was introduced.
CN Tower in Toronto, Canada, the tallest slip-form building, was constructed.
Water Tower Place in Chicago, Illinois, the tallest building was constructed.
Superplasticizers were introduced as admixtures.
Silica fume was introduced as a pozzolanic additive.
The "highest strength" concrete was used in building the Union Plaza constructed in Seattle, Washington.
311S Wacker and Two Prudential Plaza in Chicago sets new height record at 920 ft.
The tallest reinforced concrete building in the world was constructed at 311 S. Wacker Dr., Chicago, Illinois.
Petronas Twin Towers, 1476 ft.
HTC, originally a Swedish company, introduced concrete polishing to the United States. The first installation in the US was a 40,000-square-foot warehouse floor for the Bellagio in Las Vegas. The popularity of polished concrete has soared in just the few short years it has been around, it is now being used in retail locations and even residential homes.
Portland-Limestone cement to reduce carbon footprint
Concrete structures formed with 3D Printers
Accelerated precast concrete construction
Transparent concrete introduced in modern architecture