Abstract: Since the rockbolt is in the state of high bearing stress after the deformation of surrounding rock, it is easily to fail due to blasting vibration, earthquake and other dynamic loads in the deep rock mass engineering. Therefore, it is urgent to study the mechanical response mechanism of the bolt under dynamic disturbance. Based on the SHPB system, a set of testing equipment was developed for studying the dynamic response of bolts. Then the mechanical response characteristics of full-length bonded bolts were investigated under dynamic disturbance. The slippage of bolt increased with the increase of the incident energy at initial dynamic load, and the peak value of stress wave decreased with the increase of propagation distance. When the stress wave propagated to the farthest end of bolt, the peak value of stress wave decreased greatly. After the second dynamic load, the peak difference of stress wave between strain gauge SG1 and strain gauge SG2 was obviously smaller than that at the first time. This result indicates that the anchorage interface begins to damage from the outside of the anchor under the dynamic load. The failure of the anchor is related to the damage of the anchor interface. The anchorage interface is damaged after the first time loading. Then the damaged anchor bolt will be further deteriorated by the external load (such as secondary impact and rock mass extrusion). As a result, it can not resist the deformation of surrounding rock and fail. The research results provide new ideas for revealing the failure behavior of the supporting bolt and adopting the reasonable design and construction.

Key words: dynamic disturbance, high stress, separated Hopkinson pressure bar(SHPB), full grouted rock bolt, mechanical response