EXPERIMENTAL STUDY ON DISTRIBUTED OPTICAL FIBER SENSING FIELD TECHNOLOGY FOR MINING OVERBURDEN DEFORMATION

The principle of distributed optical fiber sensing technology based on BOTDR is introduced in this paper. A mineral exploration hole in Huaibei was selected to do a field study on distributed optical fiber sensing technology for the monitoring of 10414mining face overburden deformation combined with coal mining process. Monitoring program selection, laying process of sensing fiber, data processing and analysis, etc. were included in this study. The coal mining overburden deformation law was analyzed. Experimental results show that：During the mining process, there is a fracture surface between the bottom of the upper igneous rocks and lower part of the rock, the separation occurs along the fracture surface in the lower part of the rock along with slip oblique to coalface. The bottom of the under igneous rock to lower rock is compressed by the action of gravity of the overlying rock, meanwhile the amount of deformation is increasing. Experimental results further validate that the mining overburden deformation monitoring method based on BOTDR is very effective, and provides a new monitoring technique for the safe and efficient coal mining.