Experimental study on morphological characteristics of landslide dams in different shaped valleys

Landslide dams pose enormous risks to infrastructures and communities in mountainous areas near rivers, with potential dam breaches causing catastrophic secondary hazards. The morphology of a landslide dam, essential its stability, is highly influenced by formation conditions, including the type, material composition, valley shape. However, correlation between these factors poorly understood. A series laboratory tests were conducted investigate damming process deposition across three different granular materials, two sliding widths, shapes. Detailed topography surveys deposits using 3D laser scanner. experimental results show that width path shape have significant effect on dam. under narrow are more concentrated higher steeper upstream downstream slopes. cross-valley profiles dependent for well-graded gravel sand (Soil I, GW) poorly-graded II, SP) but linear III, SP). crest surface frontal angle soil III larger than soils containing (i.e., Soils I II). length increases as changes from rectangular trapezoidal then triangular, shows opposite trends widths gradation becomes finer. height decreases Soil II III. In addition, particles gravels) tend accumulate side whereas finer sand) bottom source side.