Replacement Of Cement By Fly Ash In Concrete

As a concrete pozzolan fly ash was never ideal.

Replacement of cement by fly ash in concrete.

Why should you consider fly ash concrete. Utilization of fly ash in concrete began for example usbr 1948 follow ing the pioneering research conducted at the university of california berkeley davis 1937 the last 50 years has seen the use of fly ash in concrete grow dramatically with close to 15 million tons used in con crete concrete products and grouts in the u s. At full hydration concrete made with regular cements produce approximately 1 4 pound of non durable lime per pound of cement in the mix. As per the note of table 5 of this code of practice addition of fly ash quantity can be taken into account in the concrete composition with respect to cement content and water cement ratio.

The paste is the key to strong and durable concrete assuming average quality aggregates are used. Reinforced cement concrete code of practice fly ash conforming to is 3812 part 1 up to 35 can be used as part replacement of opc in the concrete. Recently techniques have been developed to replace partial cement with high volume fly ash 50 cement replacement. Different concrete samples prefabricated with various quantities of copper slag vary up to 0 to 60 as fine aggregates substitution and 20 as fly ash replacement with cement.

Fly ash can significantly improve the workability of concrete. But it was cheap the by product of burning coal and within a restricted class type class f effective.