采场老顶岩梁的超前破断与矿山压力

Break of main roof ahead of workface and ground pressure

基于损伤力学的思想 ,建立了损伤基础梁的力学模型 ,并用该模型的结论分析了老顶岩梁超前破断对支承压力及其运动状态的影响 .分析认为 :损伤基础梁模型较弹性基础梁模型能够更真实地反映支承系统与老顶岩梁的相互作用关系 ,对提高顶板来压预测预报的准确性具有重要意义 ;老顶岩梁的超前破断与回转运动是“两个应力区”形成的必要条件 .

Based on the damage mechanics, the model of damage base beam is established and the movement of main roof and abutment influenced by break of main roof ahead of workface are analyzed. The results show that damage base beam is realer than winckler beam to describe the acting relationship of main roof and its base. It is significant to improve the accuracy of roof pressure prediction. The break and rotating down of main roof ahead of workface is the essential condition forming the 'two stress zone'. The fully developing of damage of the supporting base is the main cause of interior stress zone contraction and outer stress zone extending.