  One of the major problems associated with exploitation of the copper ore
deposit in underground mines in Poland is the local disturbance in a state of
stable equilibrium manifested in a sudden release of strain energy stored in
the deformed rock mass. It occurs mainly in the form of dynamic events which
may result in rockbursts and roof falls. In order to face this threats, a
number of organisational and technical prevention methods are applied in mines.
It should be also noted that the greatest difficulties with the roof control
are observed in the vicinity of active mining fronts, where the highest
deformations are observed. The detonation of explosives generates a propagating
shock wave which may cause a serious damage to a material body that is
encountered on its way. Thus, a number of doubts during the mining operation
emerged, that simultaneous firing of group of mining faces may have the
negative impact on the condition of applied roof support and condition of roof
strata as well The article discusses geomechanical influence of multi-faces
blasting on immediate roof strata condition through the mutual comparison of
the instrumented bolts monitoring data and the computer simulations results.
The numerically assessed stress/strain field in the near vicinity of the
blasting works operation has proved to be in close agreement with the field
measured data. In the considered mining conditions both the numerical approach
and field strain/stress monitoring indicated the low effect of production
blasting on the immediate roof fall potential.
