Abstract: Based on the on-site monitoring data of deformation and electromagnetic radiation of Zhongyi Railway Tunnel of Lijiang-Shangrila, a statistical analysis was done on the characteristics of electromagnetic radiation, the relationship between the events of maximum peaks of EME intensity (N) and horizontal convergence deformation, and the relationship between the events of maximum peaks of EME intensity exceeding the average intensity (M) and horizontal convergence deformation during the deformation of the tunnel. The results show that: 1) The maximum average value of electromagnetic radiation intensity (E) increased with deformation expanding before the initial support yielded, while there was an opposite trend after the initial support yield failure. The turning time point of rising first and then falling of the maximum average value of electromagnetic radiation intensity was close to the initial support yielding. 2) The events fluctuation rate of maximum peaks of EME intensity ( ) and maximum peaks of EME intensity exceeding the average intensity ( ) were positively correlated with convergence deformation rate of the tunnel. There were positively linear relationships between the percentage of events of the maximum peaks of EME intensity ( ), the maximum peaks of EME intensity exceeding the average intensity ( ) and the cumulative deformation of the tunnel as well. Research conclusions are important in the perspective of advancing the understanding of electromagnetic radiation characteristics during the deformation process of underground cavern and enhancing the field application level of monitoring technology of electromagnetic radiation.

Key words: tunnel, electromagnetic radiation, intensity, deformation, event