Roman Pozzolanic Concrete
Randall Hostetter History 135: World Civilization Dr. Ian Wendt August 17, 2011 Roman Pozzolanic Concrete The Roman Empire has contributed a wide variety of knowledge, ideas and technology to the world. These include novel concepts regarding the legal system, Roman numerals, architecture and the Roman calendar. However, the development of concrete as a building material is not the first thing that comes to mind when considering the Roman contributions to civilization.
While the use of concrete predates the Roman era, the Romans discovered important improvements to the way that concrete is produced and used. Being that concrete is strong, inexpensive and easy to work with, this discovery has had a lasting impact on civilizations and how they construct buildings and infrastructure. Concrete is a mixture made up of an aggregate, a binding agent and water. Typically the aggregate is gravel, sand or small stones. This is the filler that gives the final product its mass.
The binding agent is what causes the mixture to set and harden. When the aggregate and binding agent are combined with water a thick mixture is created that can be poured into a form which then solidifies. In early civilization the binding agent was typically limestone powder or gypsum. The Romans discovered the use of pozzolana as a binding agent (Yegeul, n. d. ). Pozzolana is a fine, sandy, volcanic ash which when used as a binding agent creates a strong durable concrete (Wikipedia, 2011, Pozzolana).
For the Romans, concrete was the perfect building material. Its great strength made it possible to erect enduring structures such as amphitheaters, aqueducts, dams and bridges. Because it could be poured, it was easily formed into nearly any shape that was desired. The Romans developed domed roofs and arches known for their strength which became common types of architecture during this time period (Bulliet, 147). Concrete did not require particularly skilled craftsman to work with it and as such was more cost effective than other materials. Also, it was faster o use concrete in construction than the cut stone that was common in the Greek era (Yegeul, n. d. ). Another benefit of pozzolanic concrete was that it could be hardened under water. Harbor structures such as piers were constructed using this type of concrete. Some of those piers still exist today in the Roman port of Cosa (Wikipedia, 2011, Pozzolana). Other Roman structures which remain to this day include the Pantheon in Rome, the Baths of Caracalla, and numerous aqueducts (Wikipedia, 2011, Cement). Concrete today is primarily made with Portland cement.
Portland cement, which is a binding agent, is produced from a processed mixture of limestone, clay and gypsum. However, certain types of concrete today still use pozzolana or fly ash which has properties very similar to pozzolana (Wikipedia, 2011, Cement). There are numerous benefits to using cement made with fly ash. This type of concrete is more durable because it is less porous and more resistance to sulphates. When using pozzolans or fly ash in concrete, less water is needed in the mixture and it is easier to work with (EcoSmart Foundation, 2011).
Applications where pozzolanic concrete is used today include structures which are submerged in water such as dams, bridges and harbors. Concrete is found as a building material pretty much worldwide. The Roman contributions to the technology behind concrete have certainly helped pave the way for the construction of many civilizations. Without concrete, the construction of buildings and infrastructure would be vastly different worldwide. Works Cited 1. Yegeul, Fikret. ” Roman Concrete. ” Web. 14 August 2011 <http://archserve. id. csb. edu/courses/arthistory/152k/concrete. html> 2. “Pozzolana. ” Wikipedia, 2011. Web. 14 August 2011 <http://en. wikipedia. org/wiki/Pozzolana> 3. Bulliet, Richard W. , et al. The Earth and Its Peoples: A Global History Volume I: to 1550. 5th Ed. Boston: Wadsworth. 2012. Print. 4. “Cement. ” Wikipedia, 2011. Web. 14 August 2011 <http://en. wikipedia. org/wiki/Cement> 5. “THE FACTS what is it? ” EcoSmart TM Foundation, 2004-2011. Web. 14 August 2011 <http://www. ecosmartconcrete. com/facts_what. cfm> | |