Evaluation of Explosives Performances on Granite, Calcitic Marble and Dolomitic Marble

摘要

The study investigates the performance of different explosives on some selected rock types. To achieve the set objectives, field measurements were conducted using scanline method and clinometers for determining discontinuity spacing and dip, dip direction of discontinuities respectively in Julius Dinga Ltd Iyuku, Geoworks Ltd Igarra and Freedom quarry Ikpeshi all in Akoko-Edo in Edo State of Nigeria. In general there are two sub-vertical joints with the following dips and dip directions, for Julius Dinga Nigeria Iyuku granite are 85° and 344°, 85° and 317°, for Geoworks Igarra calcitic marble are 85° and 041°, 84° and 056° and for Freedom Ikpeshi dolomitic marble are 86° and 321°, 82° and 041° respectively. The in situ block size distribution was also estimated using both empirical and AutoCAD?. Joint spacing, block volume and volumetric joint count methods were used for empirical block size estimation. Four different types of explosives that is Special gelatine, Emulsion, Slurry and ANFO were used to carry out four blasting operations each on three types of rock selected. Out of the four explosives used, Special gelatine is the most efficient explosive for blasting of granite with efficiency of 64% and over efficient for other types of rock that is it turn them to powder, Emulsion is found the most efficient explosive for blasting of calcitic marble with efficiency of 62%, Slurry is the most efficient explosive for blasting of dolomitic marble with efficiency of 64% and ANFO is found inefficient for all selected rocks except to be used as low explosive combined with other higher explosive.