Small-Scale Flume Test under Dynamic Condition for Rock Avalanches

The objective of this research is to study dynamic behavior and responses of rock avalanche. A series of small-scale flume tests was performed on a shaking table subjected to sine waves. Simple constrained flows were generated by releasing granular materials down a flume with two inclined portions at an assigned position. Material type and the frequency and amplitude of input sine waves were varied respectively to investigate their influences on run-out. Besides, superposition mode (simultaneous release and shake) was proposed to reflect the superposition of static and dynamic effects, comparing non-superposition mode (release first and then shake). Results show that run-out increased with decreasing frequency and increasing amplitude. The difference in run-out at various amplitudes reduced when the frequency increased. The run-out was more sensitive to frequency at large amplitude than that at small amplitude. Coarse materials went further than fine materials under dynamic condition. The increment of run-out in superposition mode was larger than that in non-superposition mode at 200 and 300 gal, and was smaller at 400 gal. The increment of run-out increased as the frequency reduced and the amplitude increased in these two modes.