Why Do People Evacuate because of Concrete?
Aerated concrete is a building material that gained its popularity in the second half of the 20th century. Since it is extremely affordable, light and easy to use, aerated concrete has been used in a number of public buildings in Europe and in Britain, more specifically.
Recently, however, many specialists have expressed concern that the material is no longer safe to use, with even some experts sharing opinion that aerated concrete is much weaker than standard concrete, so, the word should not even be used in its name.
What is the difference between concrete and aerated concrete? It is a cheaper alternative to standard concrete, it is produced faster and it is easier to install. Concrete mainly consists of cement, water, sand and crushed stone or gravel. Aerated concrete, also known as cellular concrete, consists of cement, water, sand, crushed stone and a gas-forming agent. This agent produces gas bubbles during the curing process creating the porous structure of aerated concrete blocks. Aerated concrete is a light and porous material with low compressive strength, but good thermal insulation and sound absorption, while concrete is a hard and heavy material with high compressive strength.
Last year in England, more than 230 schools were found to be partly built with aerated concrete. Because of it, many of them were partially closed due to damage or wear of the aerated concrete. The lifespan of buildings built with aerated concrete is about thirty years.