Abstract:
The substrate entrainment mechanism of rock avalanches is always a research hotspot and a key scientific issue in the field of landslide dynamics, as it can greatly change the rheological regimes and mobility of avalanche mass by eroding and entraining substrate materials. Focusing on the research of the substrate entrainment mechanisms of rock avalanches, a systematic review of the representative achievements in this field is conducted here. Firstly, the typical sedimentary structures attributed to the interaction between avalanche mass and substrate are summarized in detail, including diapiric structure, flame-like structure, shearing zones, et al. Then, a review of the most significant achievements related to the mechanisms of rock avalanche substrate entrainment effect is carried out. This includes the mechanical implications of the landslide-teconized sedimentary structures in rock avalanches, the physical and mechanical processes related to the entrainment effect of rock avalanches, and studies on rheological constitutive models. Based on these, a controversial issue regarding whether the entrainment process can facilitate the high mobility of rock avalanches is discussed, with some key scientific issues being proposed. These include the mechanics of erosion and entrainment processes in rock avalanches, the substrate entrainment dynamics relying on the spatial and temporal evolutions of landslide-teconized forms, and the transition mechanisms for the path-dependent flow regimes in rock avalanches.