The History of Portland Cement. Whew! What a Long, Strange Trip It’s Been

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The History of Portland Cement. Whew! What a Long, Strange Trip It’s Been: this would be about the history of white portland cement and it’s importance in building cement related matter.

Type I/II – General Use Cement

Type III – High Early Strength Cement

Type IV – Low Heat Cement

Type V – Sulphate Resisting Cement

The manufacture of portland cement is a complex process and done in the following steps: grinding the raw materials, mixing them in certain proportions depending upon their purity and composition, and burning them to sintering in a kiln at a temperature of about 1350 to 1500 ⁰C. During this process, these materials partially fuse to form nodular shaped clinker by broking of chemical bonds of parent rock. The clinker so obtained is cooled and ground to a fine powder with the addition of about 3 to 5% of gypsum. The final product obtained is portland cement. A diagrammatic representation of manufacturing process is given below:

Portland cement, the basic ingredient of concrete, is a closely controlled chemical combination of calcium, silicon, aluminum, iron and small amounts of other ingredients to which gypsum is added in the final grinding process to regulate the setting time of the concrete.

The use of portland cement for producing mortars and concretes dates back to ancient times. The originators were naturally the ancient Greeks and Romans who made use of lime for making mortars. The Egyptians developed hydraulic limes which were used as a matrix in some mortars.

It is interesting to note that in 1756 the first true portland cement was patented by Joseph Aspdin of Leed, England. Aspdin named it portland cement because it resembled a stone quarried on the Isle of Portland off the coast of England. The name has been retained ever since.

The Portland cement is a building material that is produced by mixing raw materials, which contain lime, silica and alumina, and crushing them. The product is obtained by burning the mixture at high temperature that makes the raw materials to react chemically. The product is then ground into fine powder and it has gray color or sometimes white if the limestone used as raw material is not colored.

The name Portland cement was given to it by Joseph Aspdin. He obtained it by burning finely crushed chalk with finely crushed clay in a lime kiln until carbon dioxide was driven off, leaving behind calcium silicate. The cement was then ground to powder and sold as Portland cement because he thought the concrete made from it looked like stone quarried on the Isle of Portland.

Portland cement is one of several types of hydraulic cements based on natural cements made by burning argillaceous limestones at moderate temperatures. In 1824 Joseph Aspdin obtained a patent for a cement he called “Portland cement” because concrete made from it resembled portland stone, a well-known rock used extensively in England for construction of docks and harbors.

The history of Portland cement (the most common type of cement in general use around the world today) began in 1756, when British engineer John Smeaton experimented with combinations of different limestones and additives, including trass and pozzolanas, to develop a material superior in strength and durability to the commonly used natural cements made from crushed rocks containing clay.

Smeaton’s “artificial cement” was produced by burning a mixture of limestone and clay together in specially designed kilns. The resulting clinker was then ground with a small amount of gypsum into a fine powder to make ‘Roman cement’, which was patented by Joseph Aspdin in 1824.

The modern day product closely resembles Roman cement, though the process of manufacture has changed little over the intervening years. The essential components of this are still limestone and clay or shale.

In the 1830s William Aspdin developed new manufacturing techniques that produced a stronger, more homogeneous mixture and opened a factory at Northfleet in Kent, England. The product from these early kilns however did not resemble modern Portland cement but was a first step in that direction.

In 1843 Joseph Aspdin’s son William Aspdin had left his father’s company and in his cement manufacturing

The history of Portland cement is a little like the history of the computer. The date usually given for the first production of Portland cement is 1824, when Joseph Aspdin was granted a British patent for “an improvement in the mode of producing an artificial stone.” Aspdin’s product was made from finely-ground chalk or limestone mixed with clay and then burnt in a kiln. It had to be ground very finely (“as fine as talcum powder,” according to Aspdin), because the finer it was, the more rapid and complete the hydration reaction that occurred when water was added. Aspdin called his product “Portland cement” (it was similar to the high quality building stone found in Portland, England), although he did not patent that name.

When Aspdin made his product, he used a technique known as grinding in lathes. This involved mixing moistened raw materials with a paddle or oar in a tub until they reached a suitable consistency, then tossing them into a vat where they were ground by hand by workers walking on them with their feet. The resulting mixture was placed into kilns where it would be fired to temperatures between 2200 and 2800 degrees Fahrenheit. After firing, workers would remove the clinker from the kil

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