Research on deformation monitoring of roof surrounding rock based on microwave interference technology

Deformation monitoring of roadway roof surrounding rock is crucial for mine safety production. Ground-Based Synthetic Aperture Radar (GB-SAR), which utilizes microwave interference technology, is an advanced instrument for high-precision, non-contact monitoring of minute surface displacements. It has proven effective in applications including disaster prevention, mitigation, and emergency response. This paper utilizes a self-developed portable roof dynamic monitoring radar. Based on an analysis of the statistical model for electromagnetic wave propagation attenuation in mines, an analytical model for suppressing multipath effects in the limited space of a roadway is developed. Subsequently, a Delaunay triangular mesh with PS (Permanent Scatterer) environmental compensation is constructed to achieve high-precision inversion of displacement from FMCW (Frequency Modulated Continuous Wave) signal phase. Finally, a field experiment was carried out in a Chinese mine to validate the system. Comparative analysis between the key area deformation data (reaching 6.7 mm cumulative displacement and a peak rate of 3.8 mm/h) and electromagnetic radiation monitoring results confirmed the system’s applicability. It thereby demonstrates a proven capability to provide technical support for day-to-day safety in mine and tunnel operations, as well as for emergency response sites following disasters.