Energy conversion of the high-speed landslide movement process based on a sliding surface partition mechanical model

Abstract

High-speed landslides have the characteristics of fast movement speed and rapid spread. Therefore, it is necessary to study the whole movement process of landslides starting, accelerating and resting.Based on the mechanical properties of the sliding surface, the sliding surface is divided into an elastic medium region and a strain weakening region, and a two-dimensional mechanical model of a high-speed landslide is constructed. The energy calculation formulas of landslide initiation and landslide movement processes are proposed. Taking the Qianjiangping landslide as an example, the initiation speed of the landslide is 2.35 m/s by using the energy calculation formula of landslide initiation. According to the sliding surface morphology, the landslide movement trajectory can be divided into a fast acceleration stage, a steady acceleration stage, a steady deceleration stage, and a sharp deceleration stage. The maximum speed is 16.8 m/s during analysing the motion process. The elevation plane of the landslide front is taken as the potential energy datum plane to analyze the variation in different energy and total energy ratios. In the four movement stages of the landslide, the proportions of kinetic energy were 9.1%, 25.6%, 15.1%, and 0%; the proportions of friction loss energy were 5.5%, 58.8%, 81.7%, and 95.5%; the proportions of potential energy were 85.2%, 14.2%, 0%, and 0%;and the proportions of other resistance energy consumption were 0.2%, 1.4%, 3.2%, and 4.5%. The research conclusions are of great significance to the hazard mechanism and risk analysis of high-speed landslides.

Keywords

• mechanical model
• landslide movement process
• qianjiangping landslide
• energy loss
• landslide speed