There are many types of slope failure, collapse and landslides that are common. Part of the rock and soil in front of the steep slope suddenly separated from the main part, the process of tumbling crash caving or falling to the bottom known as the collapse. Landslide occurs when the slope changes from a stable to an unstable condition. The landslide is part of the rock and soil along the pre-existing geological interface or the newly formed shear failure surface sliding down. In the slope failure, the landslides have the most serious destructive.
The instability of the slope is related to the destruction of the soil under shear stress. The shear stress and soil shear strength affect the stability of the slope such as the geologic properties and the changes of soil mass in the slope, the relationship between discontinuities stratum and inclination surface of the slope. The change of slope size and shape and erosion or excavation to the edge of the slope with a natural or artificial load on the slope, the change of groundwater level in the slope and the transient vibration caused by the earthquake and blasting will all influenced by the stability of the slope. The slope failure is mainly due to the gravitational and pour water pressure, especially in the excavation formed slope and embankments.