The aim of this experiment was to determine the effect of
replacing a percentage of OPC with GGBS however there could have been some
errors during the experiment which could have affected the result.
The results could have been affected by lost of product
which could occur whilst measuring and pouring the OPC and GGBS into the tray
some of the product could have been left behind and dusting can occur whilst
dry mixing this could have been sorted by adding a tiny bit more OPC and GGBS
then recommend. Human error could also affect the results because maybe too
much water was added or too less and there needs to be a correct specific
amount of water need to be added otherwise the strength of the cube will be
effected to prevent this from slowly add the water until the mixture is a workable
paste and mix a little longer to make sure the mixture is well combined.
Mixture A had the most OPC and the heat raised until after 3
minutes which dropped by 0.9 and raised after a minute by 0.1 and dropped again
after 5 minutes by 0.1 and stayed at that temperature. Mixture D had the least
amount of OPC and most amount of GGBS the temperature slowly raised for two
minutes by 0.1 and on the 3rd minute stayed constant. Mixture C
raised after two minutes by 0.1 and stayed at that temperature for 9 minutes
then dropped by 0.1. mixture B did not have any dramatic drops like mixture A
it slowly kept on rising then stayed at the same temperature for 4 minutes and
raised again then after two minutes dropped by 0.1. According to the results mixture B (75% OPC
& 25% GGBS) is the best ratio replacement for cement it had the best heat
of hydration which is necessary for the cube to cure, even though mixture B and
the least amount of water then the rest and mixture D had the most.
The cube cross-sectional area is 10000m2 and the
cube volume is 0.001m3 in cube mass, density the lowest was A4
mixture D and the highest was A2 mixture B the same goes for failing load and
compressive strength. From the result mixture B is the best and that 75% OPC
and 25% GGBS is the best ratio for cement replacement actually even better than
cement alone. Mixture B had the best
heat of hydration and was the strongest cube out of all four.