Rock blasting vibration velocity and excavation damaged zone for the high-level radioactive waste geological disposal

Abstract

Based on Beishan Exploration Tunnel (BET), the blasting test has been carried out and studied deeply, especially the blasting vibration velocity and excavation damaged zone (EDZ) have been monitored immediately along the blasting cycles. It has obtained that the maximum blasting vibration velocity ranged from 4 cm/s to 60 cm/s. Meanwhile, the EDZ tested by the radar system is ranged from 17 cm to 24 cm. Furthermore, as the cutting method, surrounding hole distance and specific charge are different, the maximum blasting vibration velocity and EDZ are also diverse caused by the blasting energy release, distribution, absorbing, and transfer. Finally, the controlling method with rock damaged depth using the maximum blasting vibration velocity at the distance 10 m is proposed. Through the blasting vibration velocity attenuation law and rock damaged characteristic, the threshold of the maximum blasting vibration velocity at the distance 10 m has been confirmed, i.e. when the maximum blasting vibration velocity is under 100 cm/s, the rock damaged depth could be controlled within 30 cm. Then the blasting damaged zone could be ensured and confirmed. The research and theoretical knowledge could be applied to the blasting and excavation of the deep geo-engineering and the HLW geo-disposal.