Application of Conical Shaped Charges for Dimensional Stones Blasting

摘要

A new technique of dimensional stones blasting for achieving directional rock cutting by conical shaped charges is proposed in this study. This technique has many advantages like precisely controlling numbers and propagation directions of cracks under blasting, having a complete rock excavation face, and maintaining surrounding rock and slope's stability. So it can be applied to quarrying, underground excavation, tunneling, rock slope blasting, bench blasting and dimensional stone blasting.rnIn order to understand the behavior and process of rock cutting by conical shaped charges, theory analysis and in-situ testing are included in this research. Theory analysis are basic principles of shaped charges and rock fracture mechanics used to find out which blasting parameters will influence the success of dimensional stone blasting. In-situ tests are two field tests conducted in eastern Taiwan quarries to cut marble and serpentine dimensional stone blocks respectively. The result shows that using conical shaped charges to cut dimensional rock block is practicable and advantageous. Comparing with traditional dimensional stones blasting, less charge concentration and large hole spacing was utilized in rock splitting operations. In these tests, charge mass per meter was less 30 grams, but hole spacing is almost over 40 centimeter. It will be undertaken that less explosive will decrease rock damage and large hole spacing will promote efficiency of rock splitting operations.