Simulation on Flyrock due to Blasting Using Smoothed Particle Hydrodynamics (SPH) with LS-Dyna software

Abstract

In surface mining operation, blasting method has been commonly used and accounted highly for breaking waste rock and mineral. The main goal of the activity is fundamental fragmentation by energy generation due to blasting. However, only 20% to 30% blasting energy is generated to fragment rock. The remain energry is wasted for flyrock, ground vibration, air overpressure, dust and too fine fragmentation. Flyrock in blasting is large risk for surface mines and occupies more than a half of incidents relating to blasting at surface mines, because this is a severe issue and causes negative reaction of the surrounding residients. However, studies on flyrock-phenomenon prediction methods for blasting in Vietnam have been also limited. In the study, simulation analysis method on induce-blasting-induced flyrock experiment using Smoothed Particle Hydrodynamics (SPH) with LS-Dyna software. Two-dimension modelling was built and practically applied for B2 cross section of Mong Son quarry in Yen Bai province. The result showed that the ability of Smoothed Particle Hydrodynamics (SPH) in analysizing flyrock trajectory distance in blasting. By using the modelling with field-site parameters, the researcher monitored flyrock velocity at installed time periods, such as 1.5 second when the flyrocks fly with a maximum distance of 85 m from blasting site and their average velocity of 40 m/s.