Pozzolanic properties of fly ash

The pozzolanic properties of fly ash are undoubtedly related to the glass and they are improved with increasing content of this phase and of the fineness of fly ash. The following factors are cracial for fly ash of good quality ... 

In the early days of the power generation industry, coal combustion products (CCPs) were considered to be a waste material. The properties of these materials were not evaluated seriously for other uses and nearly all of the CCP were landfilled. In the course of time, the cementitious and pozzolanic properties of fly ash were recognized. The products were tested to understand their physical properties, chemical properties, and suitability as a construction material. During the last few decades, these waste materials have seen a transformation to the status of by-products and more recently products that are sought for construction and other applications (Chapter 14). 

Salvador, S. (1995) Pozzolanic properties of fly ash—calcined kaolinite a comparative study with soak-calcined products. Cement and Concrete Research 25, 102-112. 

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