煤巷掘进过程中能量转化机制研究

Study on energy conversion mechanism during coal roadway excavation

巷道掘进是保证采掘接续的必要基础。以煤巷掘进过程中能量转化机制作为切入点,在理论上分别建立储存总能、弹性区变形能量、塑性区耗散能量之间的方程式。通过三轴加卸载试验,具体讨论围压与煤体储存能量、卸载速率与能量的释放、升轴压速率与能量的演化之间的关系。数据分析可知:围压越大,煤体储能越大;围压不变的情况下,卸荷速率越大,煤体释放能量越小;升轴压加载速率越大,破坏时的围压和轴压强度越大。此研究可为煤巷掘进过程围岩的稳定性包括预测岩爆、空顶距最值确定、掘进速度等提供借鉴。

Roadway excavation is the necessary foundation to ensure the continuity of mining and driving.Taking the energy conversion mechanism in the process of coal roadway excavation as the starting point, the equations between the stored total energy, the deformation energy in the elastic zone and the dissipated energy in the plastic zone are established theoretically.Through triaxial loading and unloading test, the relationship between confining pressure and coal storage energy, unloading rate and energy release, and the relationship between the rate of axial pressure rise and energy evolution are discussed in detail.Data analysis shows that the greater the confining pressure, the greater the energy storage of coal body;when the confining pressure is constant, the greater the unloading rate, the smaller the coal body energy release;the greater the rising axial loading rate, the greater the confining pressure and axial compression strength during failure.This study can provide a reference for the stability of surrounding rock in the process of coal roadway excavation, including the prediction of rock burst, the determination of the maximum space roof distance, and the excavation speed.