Abstract
The American Concrete Institute 211-92 mix design proportioning method (ACI method) for normal concrete was compared with two other methods British DOE Mix design proportioning method (DOE method) and the Indian Standard mix design proportioning method - IS 10262-82 (IS method) in order to evaluate the method that gave the best workability, cost efficiency and met the targeted mean compressive strength (TMCS) within 28 days curing period. The proportioning of the materials used in the batching of fresh concrete was adequately evaluated using ACI 211-91. 75 concrete members were cast using 100×100×100 mm moulds and the compressive strength for 7, 14, 21, and 28 days were obtained after the cubes were cured in water. Studies were done to obtain the relationship between the compressive strength and Water-cement ratio, cement content, workability, Aggregate‒ cement ratio, fine aggregate content, coarse aggregate content and cost analysis was evaluated and compared for the three methods of mix design. The ACI method and IS methods were easier to proportion compared to the DOE method which was cumbersome. The compressive strength of the ACI method and IS methods met the TMCS but the DOE method did not meet the TMCS for the M15, M20, M25, M30 and M40 grades of concrete. The ACI method was more cost effective than the IS method. The ACI method was cheaper than the IS method by; 14.94%, 12.18%, 12.55%, 12.93% and 4.10% for the M15, M20, M25, M30 and M40 concrete grades respectively. The ACI method was thus, recommended as first choice proportioning method for the group studied.

Key words: ACI method, aggregate cement ratio, DOE method, IS method, normal concrete.