On March 6, 2026, a symposium on muon imaging technology for detecting potential hazards in earth-rock dams was held in Nanjing. Over ten experts from institutions including the Nanjing Hydraulic Research Institute, Lanzhou University, and Henan Zhongyuan Optoelectronics attended the event, engaging in in-depth discussions on the preliminary findings from China's first field trial of muon imaging technology applied to earth-rock dams.

First Field Test of a Complex Earth-Rock Dam System

From September to November 2025, the Muon Team from Lanzhou University collaborated with the Henan Zhongyuan Optoelectronics Team to complete China's first field trial of muon imaging in an earth-rock dam at the auxiliary dam of Mangshan Reservoir in Chenzhou, Hunan Province (an asphalt concrete core wall earth-rock dam). Three measurement points were deployed along the auxiliary dam's access road, utilizing a self-developed flat-panel plastic scintillator detector for a cumulative two-month observation period. Prior to this, international exploration of this technology had only been conducted at a sand control dam in Gunma Prefecture, Japan. Earth-rock dams constitute over 90% of China's reservoir structures. Characterized by highly heterogeneous materials and complex geometries, these dams pose challenges for traditional destructive drilling sampling methods. Existing geophysical techniques like electrical and seismic surveys suffer from limited resolution and susceptibility to environmental interference. This trial marks the inaugural application of natural muon imaging technology as an innovative geophysical exploration method within complex earth-rock dam systems.

Preliminary Results: Multi-point Deployment Enables Three-Dimensional Density Imaging

At the meeting, Wu Su, General Manager of Henan Zhongyuan Optoelectronics, first introduced the project background and significance. Subsequently, the Lanzhou University team systematically presented the principles of muon imaging technology, along with its field implementation and preliminary results in detecting the auxiliary dam structure at Mangshan Reservoir. Experts from the Nanjing Institute of Hydraulic Research also shared findings on tracing the source of seepage defects in the dam. Preliminary three-dimensional density inversion results from muon imaging demonstrated the technique's sensitivity to density distributions in complex terrain conditions. This holds promise as a novel technical approach for detecting internal structures and identifying potential hazards within earth-rock dams.

Experts at the conference agreed that this technology holds significant potential for application in long-term dam health monitoring and is expected to serve as a powerful supplement to existing safety monitoring systems. The next step will focus on optimizing detector deployment techniques and enhancing detection accuracy to advance the technology toward practical engineering implementation.