Study Of Physical Precursors Of Failure Of Large Scale Rock Blocks In Relation To Earthquake And Rockburst Prediction

Investigation of deformation and destruction of big blocks of rocks allows specified study in space and time of variations of physical features of material search. That are precursors to failure. The use of large-scale models of about lm3 permits on the one hand simulation of the seismic process 3 permit the of a dense observation network for analysis of variations of physical parameters in space. Comparative analysis of variations of physical fields in time has resulted in selection of precursors of failure in plane strain tensor, clastic waves velocities, acousticactivity, electric self potential, electrical resistance, etc. . . It is shown that precursors are influenced both by the block material and loading conditions. As the moment of macrofailure comes nearer, the number of precursors of various types increases, this makes the prediction more reliable. However, the multifactor connection of separate physical properties with micro and macrofailure of internal structures makes it difficult to interpret the measurements of separate physical parameters and to predict failure, especially in its early stages. The possibility to distinguish the early stages of microfailures and to predict the local macrofailures by means of complex statistical parameters which is derived from a few physical precursors are shown.