Abstract: During mining，due to the corner effect of the roof breaking，the roof often breaks in an arc shape at the intersection of the supporting boundary when it fails，leaving two small arc-shaped blocks. At present，when applying the thin plate theory to study the characteristics of the roof pressure，the influ⁃ ence of the small arc-shaped blocks is ignored and the rectangular elastic thin plate model is used for cal⁃ culation. In order to analyze the influence of the corner effect of plate breaking on the periodic pressure characteristics of the roof，the maximum stress of the elastic thin plate considering the arc-shaped blocks was solved by the difference method，and it was compared with the maximum stress of the rectangular thin plate model. Through comparison，it can be seen that the maximum stress of the roof considering the corner effect of plate breaking can reach up to 1.27 times the maximum stress of the roof without considering the effect，but when calculating the periodic weighting step，the difference is small. Therefore，when estimat⁃ ing the maximum stress of the roof，the corner effect of plate breaking should be considered，and when esti⁃ mating the periodic weighting step of the roof，the influence of this effect can be ignored.

Key words: roof, corner effect, the periodic pressure characteristics, the difference method, elastic thin plate model