EVALUATION OF THE EFFECT OF PHYSICAL AND MINERALOGICAL CHARACTERISTICS OF SOME ROCK TYPES ON THEIR MECHANICAL PROPERTIES (A CASE STUDY OF EKITI, ONDO AND KWARA STATE)

S. A. Agbalajobi; M. A. Jethro; S. A. Akanbi

S. A. Agbalajobi Department of Minerals and Petroleum Resources Engineering Technology, Kwara State Polytechnic, Ilorin, Nigeria.
M. A. Jethro Department of Minerals and Petroleum Resources Engineering Technology, Kwara State Polytechnic, Ilorin, Nigeria.
S. A. Akanbi Department of Minerals and Petroleum Resources Engineering Technology, Kwara State Polytechnic, Ilorin, Nigeria.

Keywords: Physical, Mineralogical, Uniaxial Compressive Strength, Properties, X-ray Diffraction, Rock

Abstract

The research work studies the effect of physical and mineralogical characteristics of some rock types on their
mechanical properties. Samples of rock were collected from six locations, Egbejila and Odore (Kwara State),
Ijare and Itaogbolu (Ondo State), Iyin and Awo road, (Ekiti State), in Nigeria. The physical properties (hardness,
density and specific gravity), mineralogical properties (X-Ray Diffraction (XRD) and mechanical properties
(Uniaxial Compressive Strength (UCS); Point Load Strength and Brittleness) were determined in the laboratory
using the required international standard and the equipment used are Impact Testing Machine, Compression
Testing machine, Aggregate Impact Value (AIV) machine, Aggregate Crushing Value (ACV) machine, Global
Positioning System (GPS), Cut-off Saw Machine, and Petrographic Microscope. From the results of the
investigation, it was observed that the concentration of quartz and other minerals as indicated by the X-Ray
Diffraction (XRD) have influence on the highest on the mechanical properties of the rocks under study. Ijare
with the highest quartz content of 69.4% has the highest UCS of 174.4 MPa while Odore with the lowest quartz
content of 33% has the lowest UCS of 120 MPa. Dominance of silica is range of 62.455% – 70.72%). The
physical properties (hardness, density and specific gravity) were found to follow the same trend with the
mineralogical properties in influencing the mechanical behaviour of rock, most especially the UCS. Denser and
harder rock samples were found to have higher UCS. Conclusively, the physical and mineralogical properties of
rock were found to correlate strongly with the mechanical properties.