Study On Mining Failure Characteristics And Multi-field Coupling Simulation Of Deep Mining Floor Rock Mass

The deep mining engineering rock mass is usually in the complex geological environment,The water,heat and force in mining process are three main factors in geological environment,which influence,restrict and interact with each other,and form the multi-field coupling effect of rock temperature field,seepage field and stress field(referred to as THM).The process has the characteristics of nonlinear dynamics and sudden,and the influencing factors are various.This paper takes Huatai Coal Mine 7501 working face confined water exploitation as the research object,and comprehensively adopts theoretical analysis,indoor test,field measurement and numerical simulation to carry out the destruction characteristics of ground floor rock mass under multi-field coupling effect under deep mining conditions.Systematic research,the main content is as follows:(1)Based on the theory of elasticity,the uniformly distributed load on the plane of an elastic semi-infinite body is established.The calculation model for the mining mechanics along the working face was established,and the formulas for calculating the vertical stress,horizontal stress and shear stress at any point in the floor rock mass under the action of the confined and unconfined water were deduced,and the stress isoline diagram was obtained based on the Origin.The propagation law of the stress in the floor rock mass under the presence and absence of confined water was studied.The depth of rock failure and its spatial distribution were studied.(2)A similar simulation model for water inrush from mining floor was established.As the work surface continues to advance,monitoring and in-depth analysis of the evolution law of the inrush characteristics such as stress,displacement,fracture expansion,and seepage variation of the floor rock mass are performed.The actual failure depth of the floor of the 7501 face and its failure characteristics were analyzed on the site.(3)The stress-infiltration-temperature coupling equations are discussed and a multi-physics stress infiltration coupling equation for water inrush problems is established.Based on Comsol Multiphysics coupling analysis software,the characteristic effects of different structural rock masses under the coupled state of tectonic stress field,rock temperature field and groundwater seepage field were studied.The rheological characteristics and coupling laws of deep rock mass under high in-situ stress conditions are described.The characteristics of nonlinear coupling of stress field,seepage field and temperature field in water inrush from floor are analyzed.