Abstract: In view of underground coal mining and stratigraphic features in Yangliu Coal Mine, by using BOTDA fiber-optic sensing technology, the distributed monitoring methods of overburden deformation were studied, the mining-induced deformation characteristics of overlying strata were analyzed, and the separation mechanism was further explored The results show that before the coal face passing through the vertical line of monitoring hole, as the coal face gets closer to monitoring hole, overlying strata pressure becomes more obviously, stress variation is greater, and the strata behavior ranges from the top deformation zone of overlying strata to the upper stable hard rock. After coal face passing through the monitoring hole, the bed separation appears gradually inside overlying strata, where the tensile stress value steadily increases, and the stress value is related to the thickness of stable hard rock, mechanical properties, mining range, and the distance to seam roof, etc. Distributed monitoring results basically tally with the theoretical calculations．

Key words: overburden deformation, distributed monitoring, BOTDA, bed separation, coal mining