Propagation of high amplitude stress waves through a filled artificial joint: An experimental study

This paper investigates the propagation of high amplitude stress waves through a filled joint using a modified steel split Hopkinson pressure bar (SHPB) system. Quartz sand fillings with various thickness are placed in a steel tube and then sandwiched between the incident and transmitted bars to simulate the filled rock joints. Using SHPB, the incident stress waves with similar frequency spectrum but varying amplitude are induced to load the artificial filled joints. The particle size distributions of the fillings after tests are analyzed. It is discovered that as the amplitude of the incident wave increases, the fillings experience three stages of deformation: initial compaction, crushing and crushing and compaction. In the initial compaction stage and the crushing and compaction stage, the fillings are mainly compacted, and thus the transmission coefficient increases with the amplitude of the incident wave. However in the crushing stage, the transmission coefficient decreases with the increase of the amplitude of the incident wave. This is a result of energy consumption due to particle crushing. The observed dependence of the transmission coefficient on the wave amplitude is consistent with the particle size distribution of recovered fillings.