Abstract: In order to realize the quantitative supporting intensity of mining roadway under depressurized mining, characteristics of floor stress distribution were discussed, coefficient of depressurized mining was proposed, and the calculation method about supporting intensity of roadway was given in this paper based on theoretical analysis, numerical simulation and field test. The results have shown that the floor zone can be divided into fractured zone (arc), decreased stress zone (parabola), increased stress zone (oval), and original stress zone. Decreased stress zone depth is 60%-70% times the width of coal face, increased stress zone is 3 times the width and 5 times the depth of external stress field length. The range about coefficient of depressurized mining is 0-1.0 and the depth of key influence areas is about 40 m. According to the field monitoring, required supporting strength of gateway decreased for depressurized mining. Although the supporting spacing increases from 600 mm to 800 mm, the roof to floor convergence decreases 46.5%, and the deformation of two roadsides reduces by 46.7%. It is rational determination to consider the effect of depressurized mining for roadway support.

Key words: depressurized mining, mining roadway, coefficient of depressurized mining, supporting intensity, quantification