Relation between Compressive Strength and Flexural Strength for Concrete Made With Crushed Granite Chippings

Abstract

The strength of concrete is its most important characteristic. This report
studied the relation between the compressive strength and the flexural
strength of concrete made with crushed granite chippings from Abakaliki
in Ebonyi State. Sixty concrete cubes of dimensions 150mm were
produced based on a design matrix. These were made, cured and tested
according to BS 1881:1983. There were three cubes for each
experimental point. Also, sixty concrete beams of dimensions 600mm x
150mm x 150mm corresponding to the mix ratios of the concrete cubes
were made, cured and tested according to the same standard. The linear
regression model equation was Y = 11.313X-19.327, where Y
represented the compressive strengths of the concrete cubes in N/mm2
and X, the flexural strengths of the concrete beams of corresponding mix
ratio in N/mm2
. ). With the confidence level of 95%, the coefficient of
correlation was 0.975, an indication of the strong relation between the X
and Y variables. t-Statistic being lower than t critical indicated that the
two data samples were likely to have come from the same two underlying
populations.