Cement saturation and the effect on stability and compressive strength of concrete

This research work is aimed at determining the effect of saturation of cement on the stability and compressive strength of concrete. Three different mix ratios were considered: 1:1½:3, 1:2:4 and 1:3:6; alongside three different water - cement ratios: 0.55, 0.60 and 0.65. The key concrete characteristics checked for were stability, workability and compressive strength. Results indicate that mix ratio 1:1½:3 produced a high workability for the three cement ratios considered, mix ratio 1:2:4 produced a low workability for water cement ratio 0.55 and 0.60 and a high workability for 0.65; while for mix ratio 1:3:6, a dry mix was produced for the three water cement ratios considered, thereby requiring additional water which eventually gave a low workability. The compressive strength results indicate that the mix with the highest values of strength were 1:1½:3 at water - cement ratio of 0.55 with a strength of 29.3N/mm2after 28 days and 1:2:4 at water - cement ratio of 0.55 and strength of 26.4N/mm2 after 28 days. The mixes with the least strength are 1:3:6 at water - cement ratio of 0.65 having a strength of 13.6N/mm2 after 28 days, and 1:3:6 at water - cement ratio of 0.60 with strength of 13.3N/mm2 after 28 days. The deduction is also made that for the three mix ratios considered, the most suitable water - cement ratio is 0.55 based on stability and compressive strength.