Ultrasonic characteristics of the disturbed coal mass

Abstract

Coal and gas outbursts are a mechanical dislocation process of a gas-logged and porous medium. The existence of the disturbed coal is a precondition of the outbursts. The study showed that the disturbed coal and normal coal are greatly different in mechanical and physical properties which decided the speeds of ultrasonic wave travelling in them. This paper presents a set of experimental measuring system and method. The results of measurements conducted in 60 min areas revealed quite different ultrasonic characteristics in different types of coal mass textures. Measuring the disturbed coal is a new way for predicting the outbursts.

Keywords

ultrasonic characteristics / disturbed coal mass / coal and gas outbursts

References

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