Regularity of particle velocity decrease with scaled distance for rockbursts and shot holes

Abstract

The paper is intended as an analysis of particle velocity generated during rockbursts in deep coal mines in the Ostrava-Karviná Coal Basin (OKCB), which are recorded at five underground seismic stations. On the other hand, we realized field measurements in open-pit coal and shale mines in northwestern and central Bohemia in the course of blasting operations. Based on analysis of experimental data it was proved that the slope of straight regression lines n of peak ground motions for rockbursts varies between values of n = - 0.8 up to - 1.5, while n = - 1.8 up to - 2.5 were found for explosions in holes. While the monitoring system in the OKCB is in a continuous operation using threecomponent seismometers WDS-2, a massive seismometer VBP-3, which enables us to record ground motions in the near zone of the explosion, was occasionally used for experiments in open-pit mines.

Keywords

• rockburst
• hole shot
• particle velocity
• scaled distance
• cylindrical and spherical waveforms