用有限元方法分析了4种切口形式的棒料切口处的应力集中情况,确定了 V 形切口是在应力切断时最易于萌生疲劳裂纹的切口形式;并分析了 V 形切口参数(如切口深度 t、切口张角θ及切口根部圆角半径ρ)对棒料应力集中程度的影响,得出当切口...用有限元方法分析了4种切口形式的棒料切口处的应力集中情况,确定了 V 形切口是在应力切断时最易于萌生疲劳裂纹的切口形式;并分析了 V 形切口参数(如切口深度 t、切口张角θ及切口根部圆角半径ρ)对棒料应力集中程度的影响,得出当切口相对深度 t/d 的值接近0.1时、切口张角取在60°～90°之间、根部圆角半径接近0.2 mm 时,对棒料应力切断最为有利。展开更多
In order to study the rules of rock bursts caused by faults by means of mechanical analysis of a roof rock-mass balanced structure and numerical simulation about fault slip destabilization, the effect of coal mining o...In order to study the rules of rock bursts caused by faults by means of mechanical analysis of a roof rock-mass balanced structure and numerical simulation about fault slip destabilization, the effect of coal mining operation on fault plane stresses and slip displacement were studied. The results indicate that the slip displacement sharply increases due to the decrease of normal stress and the increase of shear stress at the fault plane when the working face advances from the footwall to the fault itself, which may induce a fault rock burst. However, this slip displacement will be very small due to the increase of normal stress and the decrease of shear stress when the working face advances from the hanging wall to the fault itself, which results in a very small risk of a fault rock burst.展开更多
文摘用有限元方法分析了4种切口形式的棒料切口处的应力集中情况,确定了 V 形切口是在应力切断时最易于萌生疲劳裂纹的切口形式;并分析了 V 形切口参数(如切口深度 t、切口张角θ及切口根部圆角半径ρ)对棒料应力集中程度的影响,得出当切口相对深度 t/d 的值接近0.1时、切口张角取在60°～90°之间、根部圆角半径接近0.2 mm 时,对棒料应力切断最为有利。
基金Projects 50490273 and 50474068 supported by the National Natural Science Foundation of China2006BAK04B02 and 2006BAK03B06 by the Support Programs of the National Science and Technique During the 11th Five-Year Period2005CB221504 by the State Basic Research Program of China
文摘In order to study the rules of rock bursts caused by faults by means of mechanical analysis of a roof rock-mass balanced structure and numerical simulation about fault slip destabilization, the effect of coal mining operation on fault plane stresses and slip displacement were studied. The results indicate that the slip displacement sharply increases due to the decrease of normal stress and the increase of shear stress at the fault plane when the working face advances from the footwall to the fault itself, which may induce a fault rock burst. However, this slip displacement will be very small due to the increase of normal stress and the decrease of shear stress when the working face advances from the hanging wall to the fault itself, which results in a very small risk of a fault rock burst.
