Long-Term Reliability Monitoring and Evaluation of Mine Grouting Curtain Based on the Distributed Optical Fiber Sensing Technology

In order to intercept the water source around the ore body, two grout curtains were installed in a lead–zinc mine. Clay-cement slurry was injected into the underground water conducting fractures through combined drilling boreholes to form two grouting curtains with low permeability. However, the grouting curtains will deform and damage under the action of high ground pressure, water pressure and mining. Therefore, the long-term reliability of the grouting curtains need to be monitored and evaluated. We use a distributed optical fiber deformation measurement system to accurately measure the vertical deformation of the grouting curtains. The long-term monitoring results of the grouting curtains show that there are different degrees of vertical displacement at different depths, which may cause the tearing of the grouting curtains at different positions and greatly reduce the long-term reliability. The long-term monitoring results can provide a significant basis for the repair of the grouting curtains in the future.