Concrete is the most common man-made substance on the face of planet earth. There is about forty tons of this material for every human being alive. To know why, I will take you through a condensed history of concrete usage, from immemorial time to modern days and show you who the main actors were and what did they accomplish.
The discovery of concrete can be traced back to limestone, one of the major ingredients of Portland cement. To get some basic concrete you crush limestone and heat it at very high temperature, then, you mix it with water and once set, it turns into a rock.
The earliest trace of this material was found by archeologists, in Turkey, at settlements called Nevali Çori and Gobekli Tepe. Limestone was discovered in nice T shaped pillars. The age of these structures was dated at about 11,600 years ago. The discovery of the chemicals properties of limestone has been one of the major features of the stone age and has helped launch the technical revolution that followed.
Did the Egyptian use concrete to build the Pyramids? Maybe! The blocks that have been used for their construction are made of limestone, a key ingredient of concrete, it would have been much easier for the Egyptian to pour those huge blocks in place.
One of the first use of hydraulic mortar, without heavy aggregates was sometime around 700 BCE, on the island of Rhodes, in Greece, a cistern was built with hydraulic mortar using lime. Then Rome came and, with it, the use of a significant amount of concrete, the earliest reference to Roman concrete was by a renowned architect Marcus Vitruvius Pollio in his De Architectura (On Architecture). By the time of his writing, concrete was used in various form, to support the infrastructure growth of the Roman empire. The first large scale use of hydraulic concrete came in Judea, for the construction of the Harbor of Caesarea. Completed around 10 BCE. This massive undertaking required an industrial scale kilning facility for the lime and lots of logistic creativity to move all the material needed to that barren location. This construction was an experimentation for the Roman and they used what they learned for their subsequent harbor projects.
The Pantheon completed around 125 AD, was one of the most impressive concrete structure of the roman age. The dome in particular is very interesting, to this day it remains the largest unreinforced concrete dome in the world. The form used to create that dome would have been the most extensive shuttering created till the advent of the modern world. The tamping of roman concrete was an essential element of the material durability. It filled the voids in the formwork and got rid of micro cavities. The roman senate house, called the Curia Julia, built around 40 BCE is one of the few concrete structures from the Roman Empire still standing today.
There was some use of lime to make plaster and basic beams in the Mesoamerican civilization but, very sparingly and not to the scale used by the Roman before. Also, a Franciscan monk used Roman concrete in the renaissance, Fra Giovanni Giocondo, he has been studying Vitruvius work and used it to build the Pont Notre-Dame in Paris. One of the few uses of Roman concrete in hundreds of years. He published a book, On Architecture, which was Vitruvius work annotated and richly illustrated.
How modern concrete came to existence? Dutch merchants discovered Trass, in Germany, grounded it in powder and used it in mortar to make it much stronger. There is few mentions of it in some books, one of them being Architecture Hydraulique by the French engineer Bernard Forest in 1748. It never really took off then, but the French and English, took the idea and were now working on something similar.
A British engineer stood in preeminence over all the others, John Smeaton, who invented a few devices and had a prolific construction career. The construction that he is most remembered for is the Eddystone lighthouse, completed in 1759. He used hydraulic mortar for this construction and his discovery changed the world. The granite blocks construction with dovetails joints and hydraulic lime proved very strong and lasted to this day, in a different location, after the base got undermined. John Smeaton published a paper before his death titled, A narrative of the building and a description of the construction of the Eddystone lighthouse with stone, published in 1791.
Two patents by James Parker, English clergyman and civil engineer, are of interest, the second one in 1796, about natural cement. How he came out with this idea is a different story, the important part is, this was the earliest patent for a concrete like material. He sold his patent to Samuel Wyatt and Charles Wyatt. Thanks to their effort, natural cement, called Roman concrete at the time, was the primary concrete cement used over the next sixty years in Britain.
The largest use of hydraulic cement came when the British decided to build the Thames Tunnel. Build by the French engineer Marc Isambar Brunel, who, invented the first version of a tunnel boring machine. After 18 difficult years, the Thames Tunnel was completed and opened to the public in March 25, 1843, it was the first tunnel constructed under a navigable river.
On October 21, 1824, Joseph Aspdin was granted a patent, BP 5022, for a hydraulic mortar/stucco he called Portland cement. He conducted several experiments regarding different product proportions. Being a bricklayer in England back then, would have meant that his experiment needed considerable work, it was hard to get limestone and resources were limited. Joseph had a cement and bricklaying business that his two sons later joined, that’s when William Aspdin came in. He always managed to run some kind of cement business, through hard convincing and moving to different locales. His work helped out spread the use of Portland cement.
The Brits were not the only one starting to use it then. The Germans, famously, Hermann Bleibtreu, in the city of Stettin, were starting production and, by the end of the 19th centuries, the German Portland cement was considered of the finest quality in the world. In 1855 they built a full size factory that could produce 25 000 barrels of Portland cement per year.
Following the advent of international competition, the British cement industry went through a wave of consolidation that ended with a few major companies that formed the associated Portland cement manufacturers (APCM).
The use of concrete as a monolithic building material came gradually, by 1880 those structures were there for all to see but, still considered novelties. In those days most buildings were still constructed of stone masonry. One thing missing for concrete prime time was steel reinforcement which, was just starting to make his apparition. There were a few French pioneers, making some advancement, most prominently Jacques Monier, François Coignet and Jean-Louis Lambot. Lambot, a gentleman farmer from South France, constructed in 1848 a concrete rowboat reinforced with iron bars and mesh.
In North America, large scale use of concrete began in 1817 with the construction of the Erie Canal. Canvass White, the engineer in charge, went to England to study their work and came back advocating for natural cement. Then, came Ernest Ransome, one of the pioneers of concrete construction in the US, who invented rebar. In the early 1880 he patented the expansion joints. Followed in 1884, by the Ransome system, this particular design would be widely used in reinforced concrete construction for the next 30 years. One detail of his design was the fact that he used twisted iron, increasing the grip to the concrete, a novel idea then, most professional believed that this twisting action destroyed the iron but, was in fact, making it stronger.
Reinforced steel concrete was then gaining more momentum every year, slowly gaining acceptance as a major construction material. One event would demonstrate the superiority of the material more than anything else, the world first reinforced concrete skyscraper. In 1901, The Ingalls building project went ahead, and became the world tallest concrete skyscraper, at 54m with sixteen stories. It was twice the height of the next highest reinforced concrete structure in existence then and made headlines around the globe.
As the use of concrete expanded, so did the design of concrete buildings. Frank Lloyd Wright was one of the first architect to start exploring the new forms of construction being possible with reinforced concrete. Most famously he built the Unity Temple in 1908 and then the Tokyo Imperial Hotel in 1923, designed to resist a major earthquake. Also, the Johnson Wax Headquarters and research tower in 1939 and to finish, the Guggenheim museum in 1959.
One of the most famous concrete construction of modern time is, without a doubt, the magnificent Sydney Opera House, started in 1959 and completed in 1973, is now considered a wonder of the world and a landmark for all of Australia.
¹All historical data is based on Robert Courland Book, Concrete Planet