COMPARATIVE ANALYSIS AND CHARACTERIZATION OF PHYSICO- MECHANICAL PROPERTIES OF SELECTED ROCKS USING BRITTLENESS INDICES FROM EDO, KOGI AND ONDO STATES

Abstract

Most quarries producing aggregates have difficulties in selecting explosive for creating production of required rock fragments. Therefore, there is need to generate database for physico-mechanical properties of rocks. This research investigates the physico-mechanical properties and brittleness of selected rocks in order to establish their variability. Three different samples were collected at different locations; limestone from BUA (Built-Up-Area) cement, Okpella, Edo state, granite from Samchase Quarry, Ondo state, and coal from Dangote Coal Mine, Kogi state. The samples were tested for point load strength index and uniaxial compressive strength using point load tester and 1100kN compression machine respectively, Water content was done by oven drying the sample, Tensile and young modulus were estimated from the results of point load strength index and uniaxial compressive strength. The result revealed that granite has the highest UCS value of (198.36 MPa) and tensile value (2.96 MPa) but has the least water content of (0.61%) tends to be hardest and stable as compared to other rock samples. The brittle indices for limestone, granite and coal are 53.756, 66.952, and 9.254 respectively. In addition, the result of unit weight and water content of the rocks are indirectly related. It thus shows that granite having the lowest value of water content (0.61%) and has the highest unit weight value of (26.5 kNm-3), while coal that has the highest value of water content (20.60%) and has the lowest unit weight value of (15.9 kNm-3). Slake durability result revealed that granite has the highest durability in both dry and wet condition having values of 99.44% and 99.12% respectively.