Sliding and damming properties of granular debris with different geometric configurations and grain size distributions  

作　　者：HE Ligeng TAN Longmeng YANG Xingguo ZHOU Jiawen LIAO Haimei 

机构地区：[1]College of Civil Engineering,Guizhou University,Guiyang 550025,China [2]Quality Supervision and Law Enforcement Detachment of Guizhou Province Traffic Construction Engineering,Guiyang 550081,China [3]State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China

出　　处：《Journal of Mountain Science》2024年第3期932-951,共20页山地科学学报（英文）

基　　金：support of the National Natural Science Foundation of China(U20A20111,42107189).

摘　　要：Granular debris plays a significant role in determining damming deposit characteristics. An indepth understanding of how variations in grain size distribution(GSD) and geometric configurations impact the behavior of granular debris during the occurrence of granular debris is essential for precise assessment and effective mitigation of landslide hazards in mountainous terrains. This research aims to investigate the impact of GSD and geometric configurations on sliding and damming properties through laboratory experiments. The geometric configurations were categorized into three categories based on the spatial distribution of maximum volume: located at the front(Type Ⅰ), middle(Type Ⅱ), and rear(Type Ⅲ) of the granular debris. Our experimental findings highlight that the sliding and damming processes primarily depend on the interaction among the geometric configuration, grain size, and GSD in granular debris. Different sliding and damming mechanisms across various geometric configurations induce variability in motion parameters and deposition patterns. For Type Ⅰ configurations, the front debris functions as the critical and primary driving component, with energy dissipation primarily occurring through inter-grain interactions. In contrast, Type Ⅱ configurations feature the middle debris as the dominant driving component, experiencing hindrance from the front debris and propulsion from the rear, leading to complex alterations in sliding motion. Here, energy dissipation arises from a combination of inter-grain and grain-substrate interactions. Lastly, in Type Ⅲ configurations, both the middle and rear debris serve as the main driving components, with the rear sliding debris impeded by the front. In this case, energy dissipation predominantly results from grainsubstrate interaction. Moreover, we have quantitatively demonstrated that the inverse grading in damming deposits, where coarse grain moves upward and fine grain moves downward, is primarily caused by grain sorting due to collisions among the grains

关 键 词：Landslide dam Geometric configuration Energy dissipation Inverse grading Physical experiment 

分 类 号：P642.22[天文地球—工程地质学] TV64[天文地球—地质矿产勘探]