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Most coal mines in China are currently mining close coal seams. Roadways in close coal seams, especially ultra-close coal seams, confronted difficulties in maintaining, including large deformation of the roadway, roof caving, rib spalling and floor heaving. This is mainly caused by the complicated stress and geological conditions, shattered roof, improper layout and support. To explore the issues mentioned above, the theoretical analysis was used to build a mechanical model and study the stress distribution under coal pillars, and FLAC3D modelling was adopted to build numerical models with different staggered distances. The optimal roadway layout was brought forward combining the result of numerical simulation and coal recovery rate. The field practice was carried out in the tailgate of panel 25301 to investigate the effect of the layout scheme. The results of field monitoring show that the roadway’s stability is well maintained in the mining process.

The mechanical analysis model of surface-bonded fiber Bragg grating (FBG) shear strain transfer is established in consideration of the linear viscoelastic effect of the adhesive layer, which is simplified as a standard linear solid model. And the strain transfer relation is acquired and validated by anchor bar uniaxial tension experiments. There is good correspondence between calculated values and experimental results. Finally, the influences of shear modulus, length and width of the adhesive layer, and thickness of the interlayer on the instantaneous and quasistatic strain transfer are analyzed by numerical simulation.