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The Egyptians used an impure form of gypsum mixed with
water to form a paste as the bonding agent between the stone
blocks of the pyramids. The Romans used limestone, which
they crushed and burned before mixing with water. The Romans
used this mix as mortar between bricks and stones.
John Smeaton, in 1756, first produced cement by baking
limestone containing a proportion of clay.
The modern day beginnings of what is called "portland
cement" began in 1824, when Joseph Aspdin, a British
stone mason, obtained a patent for the synthetic product
that he invented. Aspdin named the product portland cement
because it resembled a stone quarried on the Isle of Portland
off the UK Coast.
Because concrete is the most widely used of all
construction materials in the world today, the manufacture
of cement is widespread. In the developed countries each
year almost one tonne of concrete is poured per capita [1].
The following hyperlinks provide great resources for
teachers and students. Resources such as: technical
notes, performance notes, material safety data sheets, examples
of concrete buildings and blocks.
The QCL website includes download-able documents
"School Kit", and "The Secret Life of Cement".
The Portland Cement Association website has a section
on "Concrete Basics" and also a "Virtual
Plant Tour" - tour a cement plant online, and "Concrete
in the Classroom" - lesson plans, activities, resources,
and more.
Next >> Bricks
Glossary
Mortar: cement mixed with sand or crushed stone
that must be less than approximately 5 millimetres in size.
Mortars are used for binding bricks, blocks, and stone in
walls or as surface renderings [1].
Concrete: a mixture of cement, sand or other fine
aggregate, and a coarse aggregate - that for most purposes
is up to 19 to 25 millimetres in size. Concrete is used
for a large variety of construction purposes [1].
Citations
[1] Britannica.com Inc (2001). ENCYCLOPÆDIA
BRITANNICA ["Cement"] [WWW document]. URL www.britannica.com/
Note: This page is under
construction, and will be added to as time permits.
Copyright D. L. Christiansen [Last updated
Sept 2002] Images: respective copyright owners noted/cited.
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