Investigation on deformation behavior of unstable rock belt based on multi-source data analysis

Slope failure triggered by collaboration of coal-mining activities, structural plane, karstification and rainfall is very frequently occurred in Guizhou, China. Subsequent four rock topples occurred in Daxian village, Bijie City since October 2022 continuously threatening the safety of the residents and exhibited a high possibility of reoccurring geohazards in the Yiziyan unstable rock belt. Temporal and spatial multi-source data from GNSS, sensors, video footage, aerial image and remote sensing are integrated to reveal the unstable rock belt deformation behavior. Detailed macro- and microscopic data reveal that slope experienced a three-stage deformation process with different displacement rate since devices started to monitor. Based on the comprehensive monitoring data, inverse-velocity method (IVM) was improved with two quantitative indexes: displaced angle and crack width, and it indicated a slope failure event approximately on 23rd June 2023. According to the prediction result, government emergently evacuated all the residents and took effective disaster management. Therefore, fatalities were avoided in the major rock topple event occurred on 20th June 2023 in Yiziyan which served as a highly valuable case of successfully forecast approaching slope failure. The modified IVM provides specific precursor of future potential geohazards in the similar geological condition in Guizhou.