From standpoint of industrial development, the world can he divided into two parts: one where the process of industrialization and urbanization began more than 100 years ago and the other where it started essentially after the end of World War ii. it seems that. in the foreseeable future both parts of the world will continue to require large amounts of building materials
Ordinary concrete, typically, contains about 12 percent cement. 8 percent mixing water, and 80 percent aggregate by mass. This means that, in addition to 1.5 billion tonnes of cement that is being consumed today, the concrete industry is consuming annually 9 billion tonnes of sand and rock together with I billion tonnes of mixing water.
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