This study investigates the compliance of the physical and mechanical properties of granites produced in some parts of Ogun State to relevant codes and standards. The desire to carry out the study was borne by personal on-site experience that single size aggregates produced in some parts of Ogun State do not conform to grading requirements specified in relevant codes and standards. Samples of 9.5mm, 12.5mm, 19mm and 25mm aggregates were collected from four different quarry sites spread across the state. The Samples were tested for their Specific Gravities, Water Absorptions, Moisture Contents, Aggregates Impact Value and Aggregates Crushing Value in accordance to the relevant standards. Test results reveals that all the samples conform to relevant codes and standards. It was therefore concluded that although the aggregates do not conform to grading specification but the physical and mechanical properties of all the aggregates meet the specifications in relevant codes and standards.

Coarse aggregate is an essential constituent of concrete constituting about 60% to 80% of concrete depending on the mix ratio. Granite is reported to be the most widely distributed plutonic rock in the earth crust. It is predominantly available in various parts of Ogun State of Nigeria. Its different properties have been known to strongly influence the fresh and hardened state properties of concrete. In this study, samples of four different sizes of granites (9.5mm, 12.5mm, 19mm and 25mm) were obtained from four different quarry sites across the state. The Physical properties such as specific gravity, moisture content and water absorption and the Mechanical properties such as aggregate impact value and aggregate crushing value of the samples were evaluated. The results of the specific gravity, moisture content and water absorption vary from 2.61 to 2.86, 0.69 to 1.22%, 0.16 to 2.13% respectively. While the aggregate impact value and aggregate crushing value vary from 18.30 to 28.12% and 6.21 to 9.45% respectively. It was therefore concluded that there are variations in the physical and mechanical properties of granites produced in Ogun State of Nigeria. The observed variations occur in relation to the various sizes and for the different quarry sites.

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The study was carried out to assess the suitability of sand available in South Western Nigeria for concrete production. Collected samples of sand were  tested in the laboratory to determine their physical properties. The properties considered are gradation, specific gravity, water absorption, moisture  content, bulking, and percentage silt content. The result of the sieve analysis indicates that while the gradation of some of the samples is within the  specified values specified in standards, others do not conform. The values of the coefficient of uniformity and coefficient of curvature is between the  range of 3.6 – 10 and 0.53 – 2.56 respectively. The values of the results of specific gravity, water absorption, the moisture content are within the range of  2.67 – 2.86, 0.67% – 2.04%, 0.75% – 3.17% respectively. Based on the fact that the result of the test on the properties of the samples tested are in  accordance with the specifications in relevant codes as discussed in the body of this work, it can be concluded that most of the samples are suitable for  concrete production while the gradation of some of the samples needed to be modified to conform to the required grading.