Some analytical and empirical methods of forecasting the stability of rocks in principal workings have been discussed, the practical importance of analogy methods being stressed, and the criteria have been examined of choosing the parameters of optimum co-operation of supports with the ground. These criteria allow for three fundamental systems of co-operation of supports of principal workings with the surrounding rocks which are in the condition of unelastic strains:
Of maximum limitation of rock deformations by using the rigid supports.
Of limited rock deformations by using the yielding supports with pre-determined maximum yieldability.
Of limited deformation intensity by using the yielding supports with constant load hearing capacity determined for the given natural and mining conditions.
In order to reach the stability of principal workings driven under difficult natural conditions closed profile supports should be used with growing load bearing capacity at a limited or controlled yieldability. Moreover, some analytical methods of computation of fundamental parameters of rock pressure and supports have been discussed taking into account the condition of dynamic rock deformations around the working. In order to reach the stability of principal workings driven under difficult natural conditions closed profile supports should be used with growing load bearing capacity at a limited or controlled yieldability. Moreover, some analytical methods of computation of fundamental parameters of rock pressure and supports have been discussed taking into account the condition of dynamic rock deformations around the working.
