Safety and stability of underground mine openings, coal pillars and water
dams in the near vicinity of operating surface mines are endangered from
excessive blast induced vibrations. This paper deals with the
investigations carried out in four coal mines. Simultaneous
measurements at equal distances from the source indicated higher level of
vibration on the surface than those produced in the underground
workings. The values of peak particle velocity (PPV) measured on coal
pillars, body of water dam were lower than those measured on roof and
junctions of the roadways. The parting of coal (3-4.5 m) between two
sections vibrated with higher PPV compared to the roof of top section and
floor of bottom section. In one case the influence of total charge fired in
a round was significant in generation of vibration compared to the
maximum charge/delay where monitoring was done vertically below the
source.