Safety monitoring and effect analysis of fracturing body on the right bank of Pubugou reservoir head in China based on space-ground-body monitoring mode

The Pubugou dam is located on the Dadu River in China, with a height of 186 m. The fracturing body at 780 m upstream of its right bank poses a major threat to the downstream reservoir area’s safety as well as the operation of the dam. In this study, a multi-source three-dimensional monitoring mode of space-ground-body is built using synthetic aperture radar, surface sensing, and rock mass stress monitoring. This makes it possible to keep an eye on the entire fracturing body in real time. This study proposes a GCPs selection method that combines the high coherence, small deformation reference points obtained by PS-InSAR inversion and stable deformation points, and realizes the high-precision bank slope deformation time series data acquisition method. It addresses the issue of strong subjectivity in the selection of ground control points (GCPs) in the SBAS-InSAR solution process in mountainous areas. The change in multiple scattering wave velocity and the evolution of the rock mass state inside the slope are both extracted using the seismic background noise cross-correlation technique. Through time series analysis and comparison of various monitoring data, the three-dimensional deformation characteristics, instability mechanism, and significant influence of rainfall on the deformation development of the fracturing body are summarized. Additionally, the adaptability, advantages, and disadvantages of various monitoring modes are evaluated. For the crucial slope of the project, a more trustworthy monitoring method will be available thanks to the mutual integration of the space-ground-body monitoring mode and data.