Concrete is the world’s most widely used man-made building material. Over one point five billion tons of cement is produced annually worldwide with around forty percent of this being used in China. The concrete made from this cement exceeds ten billion tons annually. If you can imagine how much concrete has been used over the centuries, it would be mind boggling. The history of cement and concrete goes back over five thousand years. If you trace the known history of geological cement, it goes back around twelve million years.
Let’s stick to when man was involved though and go back to the Egypt. For sure the Egyptians would have liked to have had the option we do these days of creating the pyramid using some Las Vegas precast concrete forms. The Ancient Egyptians used mud and straw along with gypsum to bind their dried bricks. To bond the great stone they used lime mortars. Near that same time the Chinese were using cementation materials between the bamboo in their boats and when building the Great Wall.
The Greeks were the first to discover how hydraulic mortars worked both in the air and in the water. This was used in the construction of waterproof tanks much like today’s Hawaii precast concrete uses similar concrete in totally submerged precast forms. The Romans then refined the mortars and are attributed to the invention of concrete by adding broken brick aggregate in a mixture of lime putty with volcanic ash or brick dust. You can still see some of their work in the Coliseum, the Pantheon, the Great Roman Baths and many more outstanding examples of how durable this new form of building material really is.
Unfortunately, after the fall of the Roman Empire, it seems concrete and cement production came to a halt. It really didn’t pick back up until the seventeenth century. Apparently, the first concrete structure to be built since the Romans was the Eddystone Lighthouse in England. The first concrete bridge was built in 1818 in Souillac France. Then in England in 1824, a man by the name of Joseph Aspdin invented Portland cement. This cement was named Portland because it bore a resemblance to the stones quarried at the Isle of Portland. It is still in use today in products like a precast concrete utility vault.
Source by Alice Lane
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