Study on Water-Inrush Mechanism and Prevention During Coal Mining Under Unconsolidated Confined Aquifer

Abstract

According to the several water inrush disasters in Qidong coal mine,we adopt field measurements and simulation experiments in this paper,to study the development characteristics of water flowing fracture,water inrush mechanism,prediction of water inrush zone,and prevention strategy,et al,while mining under the unconsolidated confined aquifer.The results show that the support crushing accident appeared before each water inrush in Qidong coal mine,which proves that it exist close relationship between water inrush accident and overburden moment.Due to the effect of load transfer of the unconsolidated confined aquifer,the adjacent key strata are prone to compound breakage,which can cause the bedrock broken as a whole in a wide range below the unconsolidated confined aquifer.Therefore,the height of water flowing fractured zone becomes obviously larger and then communicates the unconsolidated confined aquifer.This is the fundamental reason for the abnormal water inrush disaster when mining under the unconsolidated confined aquifer.Finally,prediction method to determine water inrush zone and the prevention strategy were put forward here,which guided the water inrush prevention effectively when mining under the unconsolidated confined aquifer in Qidong coal mine.