High in situ stresses and severe mining-induced stresses are the major factors causing severe deformation of deep roadways. In situ stress measurements were carried out at three typical deep coal districts in China. The distribution characteristics and factors influencing the in situ stress fields in these three deep coal mining districts were discussed. Based on the geological environments of deep coal mines, the characteristics of coal and rock deformation and damage were discussed. It is pointed out that the deformation of coal and rock mass in high stress states has obvious rheology, dilatancy and rockburst tendency properties. The high pretension and intensive supporting theory was put forward according to the deformation features of deep coal mine roadways, and the relevant bolting materials and components were also developed. Finally, the new supporting theory and materials were applied at three cases: a deep extraction entry with depth of 1,000 m in the Xinwen coal mining district, a deep gob-side entry retaining in the Huainan district, and a deep dip entry with broken surrounding rock mass in the Pingdingshan district. The geological and extraction conditions of these three deep roadways were assessed, the designs of the reinforcement forms and parameters for the roadways were carried out, and the rationality of the designs and the stability of surrounding rock masses were evaluated on the basis of the field monitoring data. These practices indicate that the high pretension and intensive supporting system, combined with grouting if necessary, can effectively control the violent deformation of the surrounding rock masses, it is a suitable technique for the deep coal mine roadways.
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