Abstract:

There is a series of features of the strata-pressure behavior of hard surrounding rock which is affected by dynamic pressure, such as the caving of the roof is difficult, sudden and large-area. In this paper we focus on the mining and support of 14-1103 working face, In view of the problems of the mine such as the roof is hard to caving, the suspension-area is huge and the safe of the working face is under a great threat, theoretical analysis and field monitoring is used in the study of the strata-pressure behavior. The study indicates that the influence of the advance on the surrounding rock stress is in the range of 100m, the scope in which the surrounding rock stress is remarkably affected is 20～30m; The maximum increasing speed of bolts’ stress is up to 55KN/d, the maximum increment is 70KN, the maximum increasing speed of roof separation is 15mm/h, the maximum increment is 67mm. However, the high speed just kept for a short time. The change of the stress and displacement is of catastrophe characteristic.

Key words: Dynamic pressure, hard surrounding rock, strata-pressure behavior, field test