Field Monitoring of Surrounding Rock Stress and Rheological Analysis in Tunnel Construction
The stress field monitor and rheological analysis have been done during excavation. The field monitoring data are compared with numerical simulation results. The result shows: Rock stress variation is influenced by both spatial effect and time effect; when the distance from monitoring section to tunnel face is less than a tunnel diameter, the surrounding rock stress is mainly affected by spatial effect and changes violently; when the distance is more than a tunnel diameter, the surround rock presents rheological properties and stress changes smoothly and continuously. Analyzing the monitoring data and fitting by Poynting-Thomson three-parameter rheological model, we can get the radial stress variation equation with time and predict the final variation value. The final value and numerical simulation results are in comparative agreement.
Q. Huang et al., "Field Monitoring of Surrounding Rock Stress and Rheological Analysis in Tunnel Construction", Advanced Materials Research, Vols. 261-263, pp. 1079-1083, 2011