Volume 3, Issue 6 (November 1975)
The Effect of Water Content on the Compressive Strength of Laterized Concrete
Laterized concrete is defined as concrete in which laterite fines replace sand. A previous paper highlighted only the salient points of difference between laterized and normal concrete. The results reported in this paper are mainly on the effect of water content on the compressive strength of laterized concrete. Other properties such as durability, resistance to frost action, and creep need to be investigated to decide whether or not laterized concrete would be usable in all climates. It is the aim of the author that this paper and his earlier paper will generate research interest in other parts of the world where facilities and climatic conditions are more favorable for the investigations of properties which are not easily investigated in the tropics.
The mix design showed that laterized concrete mixes require more water than normal concrete for equal proportions and weights of dry normal concrete and of dry laterized concrete mix. The water/cement ratio recommended for structural laterized concrete mixes of 1:1:2 and 1:1½:3 by weight is 0.65. This water/cement ratio would yield compressive strength of about 23.59 MPa (3425 psi) for 1:1:2 and 21.45 MPa (3110 psi) for 1:1½:3 by weight in 28 days. The water/cement ratio recommended for 1:2:4 mix by weight is 0.75. This would yield about 18.50 MPa (2682 psi) in 28 days.
Graphs showing the variation of compressive strength with water/cement ratio and independently with age are presented.
A schematic map of the world showing laterite deposits is included. It is suggested that the paper may generate interest in reinforced laterized concrete structural elements and that laterized concrete may eventually be used for structural works in those parts of the world where suitable sharp sand is not available, just as lightweight concrete is now being slowly introduced into major construction works.