ABSTRACT
Results of measurements covering the dynamic phenomena occurring in powered roof supports during rock mass tremors have been presented. The paper describes the applied measuring apparatus as well as the courses of underground tests. A resultant load transmitted by legs and vertical acceleration of a canopy have been determined. Courses of changes in loads of the support and accelerations of a canopy caused by tremors of the rock mass the energy of which ranged from 8*103J to 106J as well as analogous courses recorded during stress relieving blasting have been presented.
