Abstract: For complex hydrogeological conditions, the judgement about both the formation of and damage to mine water flowing channel in floor is regarded as a difficult problem. Based on charge induction monitoring technique, the relationship between the charge signal and wall thickness was examined by carrying out hydraulic fracturing tests. The charge characteristics of water channel as a function of the depth of mining space were studied. The relation between the precursor information of charge and formation of water inrush channel was explored. The results show that large pulses of charge signal and acoustic emission signal appear before the initiation pressure, and the order of two signals is random, which is related to the structure and composition of the rock mass, that the larger the wall thickness is, the greater the crack initiation pressure is and the greater the amount of charge released will be, and release of the charge is necessarily related to the force required for the deformation and failure of specimen, that wall thickness has a significant effect on the charge induced signal's in the decay time and charge accumulation, and detecting the formation depth of water flowing channel by charge induced signal is feasible.

Key words: mine, water inrush, charge induction, hydraulic fracturing, water flowing channel