基于界面模型的煤岩体冲击破坏特性研究

Study on Coal and Rock Impact Damage Characteristics Based on Interface Model

煤岩两体结构是煤岩体发生冲击破坏时的基本结构,采用RFPA数值软件探讨煤岩体中界面倾角与深部开采条件下围压对煤岩体冲击失稳破坏的影响。模拟结果表明:煤岩体的声发射能量特性与抗压强度呈现相同的变化规律,倾角越大,冲击破坏的危险性越低,界面滑移破坏的危险性越高;煤岩体在高地应力大倾角下抗压强度大小主要由围压来决定。煤岩体的破坏模型以45°倾角为界限,分为压剪破坏和界面滑移破坏2种,当α<45°时,煤岩体呈现压剪破坏特征;当α≥45°时,破坏模式转变为以煤岩交界面的滑移破坏为主。

It is known that two- body structure,formed by coal and rock,is the most basic structure of rock burst. We investigated the impact failure characteristics of coal and rock mass from RFPA,which varied with interface inclined angles and confining pressure in deep mining. The simulation result was found that the acoustic emission energy characteristics of coal and rock mass body and compressive strength presented the same variation regulation. The lower inclined angles,the greater the risk of rock burst,the higher the risk of interfacial sliding failure; the compressive strength of coal and rock mass is mainly determined by confining pressure under high ground stress and large inclined angles. The coal and rock mass damage model is line with 45°,divided into two kinds of shear compression failure and interfacial sliding failure. When α 45°,coal and rock mass presented the characteristic of shear compression failure; when α≥45°,failure mode turned into interfacial sliding failure.