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Analysis on Types of In Situ Stress Field and its Effect to Roadway in Deep Coal Mines

By analyzing a large number of in-situ stress data measured in underground deep coal mines, two types of in-situ stress fields exit in deep coal mines, σHvh and σvHh, which influences on the stability of underground deep roadways are analyzed by means of numerical simulation. The results show that the destruction of surrounding rock varies greatly in equal value stress fields with different types. In σHvh, the plastic zone of roof and floor of roadways is larger than the two sides, and stress concentration appears in front of heading face and in roof and floor of roadways, but not in two sides, more considerations should be given to the roof and floor supporting. In σvHh, plastic zone of two sides is larger than the roof and floor, and stress concentration appears in front of heading face and the sides of roadways, but not in the roof and floor, so more supporting considerations should be given to the two sides while protecting the roof.