Abrahm's law of water-cement ratio - Mathematical relation and graph
Abrahm's law expresses the relation between compressive strength of concrete mix and the water-cement ratio which is taken in designing concrete mix. This law states that the compressive strength of concrete mix is inversely related to its water/cement ratio. If water/cement ratio (w/c ratio) increases, the strength of concrete decreases. He presented his classic law as :- S = A/B* where, S = compressive strength of concrete mix * = water/cement ratio A and B are constants. The graph showing the relation between the strength and w/c ratio of the concrete mix is approximately hyperbolic shape. The graph says, lower w/c ratio is taken when the concrete is vibrated for compaction and higher w/c ratio is required for hand compaction of concrete. If we draw a line graph to show the relation between strength and c/w ratio , it shows approximately a linear relationship. Thank you. Gracious !