ANALYSIS OF PROBABILITY OF WATER INRUSH FROM GROUT CURTAIN BASED ON BACKGROUND STRESS FIELD AND MICROSEISMICITY

In order to understand the relation between background stress field of three-dimensional numerical simulation with microseismicity and water inrush probability,combining with an engineering case of grout curtain community for Zhangmatun iron mine,an operation microseismic monitoring system of ESG is used.Then,the accumulated three-dimensional geometry spaces of micro-rupture is delineated;and the possible dangerous water inrush regions of grout curtain community are divided.A three-dimensional mechanical model of curtain community is established by three-dimensional FEM,MSC.PATRAN,to simulate the background stress field distribution under high water pressure to obtain the stress field concentration region of curtain community.The comparative research results show that a large number of microseismic location events are accumulated at curtain southwest region and orebody bilateral mined-out area;the microseismicity information is very clear;original stress field greatly changes under high water pressure and mining disturbance in the above two region.There are the apparent stress concentrations here,which implies that micro-rupture will occur,develop and link under high stress.So microseismicity and background stress fields are almost consistent;and different scientific research methods illustrate the precursory characteristics of background stress field and microseismicity of grout curtain community.Then,the probability of water inrush is evaluated preliminarily.As a result,some reasonable exploitation methods and prevention measures can be adopted to provide safe measures for underground mining activities.