Geostructures, dynamics and risk mitigation of high-altitude and long-runout rockslides

Abstract

Long-runout rockslides at high altitude could cause disaster chain in river basins and destroy towns and major infrasturctures. This paper firstly explores the initiation mechanism of high-altitude and long-runout rockslides. Two types of sliding-prone geostructure models, i.e. the fault control type in orogenic belt and the fold control type in platform area, are proposed. Then, large-scale experimental apparatus and associated numerical simulations are conducted to understanding the chain-style dynamics of rockslide-debris avalanche-debris flow. The results reveal the fragmentation effects, the rheological behaviors and the boundary layer effect of long-runout avalanche-debris flow. The dynamic characteristics of quasi-static-transition-inertia state and solid-liquid coupling in rapid movement of rockslide-debris avalanche-debris flow are investigated. Finally, the risk mitigation strategy of the non-structure and structure for resilient energy dissipation are illustrated for initiation, transition and deposition zones. The structural prevention and mitigation methods have been successfully applied to the high-altitude and long-runout rockslides in Zhouqu and Maoxian of the Wenchuan earthquake zone, as well as the other major geohazards in Qinghai-Tibet Plateau and its adjacent areas.

Keywords

• Rockslide
• High-altitude and long-runout
• Sliding-prone geostructure
• Large-scale experimental apparatus
• Risk mitigation strategy
• Structural prevention technique