3 shows the change in initial and final setting time at standard consistence of binary PFA-PC paste compositions.
For ternary binders with a fixed MK content the general trend of increasing setting time (initial and final) with increasing PFA content is still maintained.
However in the current work where no SP was used there is a further marked increase in setting time at 20% MK replacement level even though there is still a fall in setting time at the 15% MK level.
it behaves as a broadly inert solid), the setting time of such a paste would be expected to increase with increase in pozzolan content.
Hence the supply of water available for the pozzolanic reaction is greater and there is more rapid formation of cementitious reaction products between the hydrating cement particles leading to a reduction in setting time.
Small amounts of MK lead to setting time increases, followed by decreases in setting times as MK levels increase further, and then at even greater MK levels setting times increase again.
Effect of admixtures on the setting time of high-strength concrete, Cement and Concrete Composites 22(4): 293-301.
53 (e) Initial setting time (mins) 130 (f) -- -- Final setting time (mins) 165 (f) -- -- Standard consistency (%) 27 (f) -- -- True material density (g/[cm.