Concrete, in the pyramids and Coliseum
![[Corel] Building a modern arena with concrete](concrete.jpg) Q: When did we first use concrete?
A: Concrete is an aggregate (usually sand and gravel) bonded together by cement.
[Corel] Building a modern arena with concrete
The Egyptians, in 3000 BC, developed a mixture similar to modern concrete by using lime and gypsum as
binders. They constructed the pyramids with these mortars.
The Romans probably are the first humans that used concrete extensively: building the Appian Way, Roman
baths, the Coliseum, the Pantheon, and the Pont duGard aqueduct.
Hillsides supported earlier coliseums but not the one built of stone and concrete in 70 AD. The Coliseum is a
freestanding structure measuring 620 by 513 feet (190 by 155 meters) and seats 50,000 spectators. The
Romans laid its concrete foundation on the site of an artificial lake. The upper structure is stone and concrete,
faced with brick. It still stands, over 2,000 years later.
(Answered by April Holladay, science correspondent, May 1, 2002)
Further Surfing:
U of Illinois: History of Concrete
|
