Abrams’ Law (developed by Duff Abrams in 1918) states that compressive strength of concrete varies as the inverse function of water/cement (w/c) ratio provided the mixture is of workable consistency. The concept remains a basis of concrete technology.
Major Concepts of Abrams’ Law
Strength and w/c ratio: Higher amount of water makes cement paste less concentrated, raises pores, and makes concrete weaker. Stronger and denser concrete is achieved at lower values of w/c ratio.
Workability Requirement: the law assumes the proportion is workable sufficient for placing and compacting. Also that excess water improves workability at the cost of strength. On the other hand, inadequate water makes concrete impractical.