Behaviour and bursting failure of roadways based on a pendulum impact test facility

摘要

Numerous tremors occur in underground mining engineering and rockbursts are related to tremors, while not all tremors can trigger rockbursts. A good understanding of the triggering criterion for the occurrence of a rockburst under strong tremor disturbance can offer useful insight into the evaluation of rockburst hazard as well as revealing the causes. Thus, a test facility was developed to investigate the behaviour and bursting failure in modeled roadway under dynamic loading. The results demonstrate that an increase in input dynamic loading energy from 29.4 J to 117.6 J did not affect acoustic emission (AE) activity, suggesting that the roadway retained its resistance to the dynamic load at that time. Then, a sharp increase in AE activity occurred at an applied dynamic loading energy of 147 J, indicating significant damage within the rock masses surrounding the roadway. Acceleration signals and deformation between roadway sections with different support patterns were different: bursting failure of the roadway section with a simulated anchoring interval of 1200 mm was severe and took the form of local bump with the roadway section being semi-closed, while the other section with a simulated anchoring interval of 800 mm could retain its structural integrity at that time. This study may eventually lead to a method for laboratory testing of dynamic behaviour and bursting failure process of roadways.