Failure history, mechanism, and recent run-out reproduction of the Xinhua Village landslide triggered by the 2022 Ms 6.1 Lushan earthquake

On June 1, 2022, at 17:00, an Ms 6.1 earthquake occurred in Lushan County, Ya'an City, Sichuan Province (30.37 degrees N, 102.94 degrees E), followed by an Ms 4.5 earthquake at 17:03 in Baoxing County, Ya'an City (30.37 degrees N, 102.92 degrees E). These two earthquakes were superimposed on continuous rainfall that began on May 6, 2022, inducing instability in the upper part of the reinforced section at the exit of the Xinhua Village Tunnel, resulting in a large high-altitude landslide. The landslide deposited material around 280 m upstream of the Baoxing Power Station dam, forming a barrier lake and causing the water level in the reservoir to rise by about 5 m. The accumulated material in the river channel is estimated to be about 200,000 m3. The residual landslide buried the tunnel exit and the National Road G351 foundation outside the tunnel, with an estimated volume of about 560,000 m3 and a maximum burial depth of 58 m. The landslide closed the G351 Xinhua Village Tunnel, affecting the operation of this important transportation corridor on the eastern edge of the Qinghai-Tibet Plateau. This research summarizes the development of the Xinhua Village landslide over the past decade under the influences of multiple earthquakes, rainfall, and heavy snow. Our research presents a preliminary investigation of the failure and kinematic characteristics of this landslide based on a field survey, unmanned aerial vehicle (UAV) photogrammetry, and 3D-MPM numerical simulation. These methods provide more detailed information about the movement of the landslide than traditional field investigation.