Fly ash cement is generally preferred for masonry, plastering, tiling, and waterproofing works. In these works, strength is not the major criteria. It has slower rate of heat of hydration which makes it less prone to cracks; and also reduces the shrinkage. Fly ash cement has better workability and finishing.
use of fly ash, which also apply to the use of raw or calcined natural pozzolans . Scope: This IR is applicable for all concrete mixes utilizing fly ash or natural pozzolans in excess of 15% by weight, per the 2010 California Building Code (CBC), Section (Section in the 2007 CBC).
cementfly ash to silica fume blend in concrete and concluded increased strength and workability due to addition of silica fume to the fly ash cement mortar. Jan Bijen  has observed the advantage of slag and fly ash added to concrete with respect to ordinary Portland cement. Barbhuiya, M. I. Russeli.
year. Although some coal fly ash is used in a range of applications, particularly as a substitute for cement in concrete. Large amount remain unused and thus required disposal. At present, coal fly ash is used in civil engineering for production of cement, concrete, cube and artificial aggregate.