Development characteristics and influencing factors of Resuo collapse on G216 National Highway at Jilong Port in Xizang Province postprint

Abstract: Since the "April 25" earthquake in Nepal, the G216 National Highway at Gyirong Port in Gyirong County, Tibet Autonomous Region frequently experiences large-scale, high-impact, high-altitude and concealed collapses, with the Resuo collapses being a typical example.The Resuo collapses, a high-altitude collapses, evades detection by conventional methods and defies early warning through monitoring systems. Such incidents have severely threatened the normal operation of the China-Nepal trade channel and caused considerable loss of life and property for both nations. Based on the existing characteristics of collapse disasters, this study analyzes the developmental features, influencing factors, and distribution patterns of such collapses, thereby providing a theoretical foundation for regional disaster prevention and mitigation efforts. The results indicate that there are two hazardous rock zones within the Resuo collapse area, encompassing 86 dangerous rock units, 20 fractured zones, and 12 slope rolling stone areas. The unstable rock mass exhibits pronounced structural features such as joints and fissures.The spatial forms of the dangerous rock units are predominantly "block or slab," with a smaller proportion being "irregular or wedge." The failure modes are primarily sliding and tipping, with fewer instances of falling. Landform, stratigraphic lithology, and geological structure serve as the internal causes of collapse formation, playing a controlling role in the development of hazardous rocks. Weathering, vegetation root splitting, and seismic activity act as external factors, promoting the formation and progression of hazardous rocks.