FORMATION AND MOVEMENT MECHANISMS OF WATER-INDUCED LANDSLIDES AND HAZARD PREVENTION AND MITIGATION TECHOLOGIES

Water-induced landslide refers to the slope instability events directly caused by water-related factors(including rainfall, fluctuation of reservoir level, surface runoff, groundwater activities and others). Southwest China is a high-incidence area of water-induced landslides, especially for reservoir landslides. The water-induced landslides directly threaten the safety of human life, property and infrastructure, and may cause far-reaching secondary disasters. It is extremely urgent to improve the level of monitoring, early warning, comprehensive control and emergency disposal of water-induced landslides. Water-induced landslide can be induced in loose accumulated formation, broken rock mass, soft rock and rock slope with soft rock interlayer or weak structural plane. Long-term evolution of geological environment, hydrological conditions and human disturbance play key roles in the development of water-induced landslide. Under uninterrupted alternation of various adverse factors, the slope gradually produces deformation and local failure with the decrease of stability and tends to the limit instability state. Finally, the short-term change of hydrological conditions makes a large-scale slope instability. The dynamic process of landslide after slope instability is very complex, especially the large-scale landslide in high elevation, which can produce strong impact disturbance fragmentation and erosion with scraping along the movement course, resulting in the change of landslide movement pattern and the increase of accumulation volume. The presence of water can intensify the erosion with scraping along the movement course and lead to the change of movement pattern to fluidization, resulting in a longer movement distance and a wider disaster-causing scope. Water-induced landslide is a complex and systematic problem. The deformation and failure processes of landslides under different geological structures and hydrodynamic conditions are quite different. Long-distance, non-contact early identification and monitoring technology, early prediction and warning method for landslide based on artificial intelligence, large data and self-learning are the important development directions in the future. The prevention and control of hydrodynamic landslide is involved with many factors such as engineering construction, economy, livelihood, and society, which needs a comprehensive application of engineering measures and non-engineering measures. In the future construction of water conservancy and hydropower engineering, much attention should be paid to the hazards of reservoir landslides, and the reconstruction facilities should be apart from the affected areas of reservoir landslides as far as possible.