摘要
为了揭示水对矿山巷道围岩岩爆的影响程度和内在机理,对取自冀西北黄土梁金矿的二长花岗岩进行了不同饱水度下的岩爆试验。结果表明:随着饱水度的增加,花岗岩的强度、储能系数、能量释放系数逐渐减小,岩爆倾向性逐渐减弱,当饱水度为0~0.4时,岩爆倾向性受饱水度影响较大,当饱水度大于0.4后,岩爆倾向性受饱水度影响较小;在压密和弹性变形阶段,AE表现为“低频低能量”,在屈服变形阶段,AE表现为“低频高能量”,在岩爆阶段,AE表现为“高频高能量”,在屈服变形阶段,AE会出现一段时间的“静默期”;AE累计事件数随饱水度增大而逐渐减小,当饱水度超过0.4后,AE累计事件数呈断崖式下跌,表明饱水度超过0.4后,岩爆剧烈程度显著下降;分形维数呈“震荡—略微减小—急剧减小—上升”的演化特征,分形维数快速下降可作为花岗岩发生岩爆的前兆特征。研究成果可为金属矿山围岩岩爆预测和水防治措施提供一定的借鉴。
In order to reveal the influence degree and internal mechanism of water on the rock burst of the surrounding rock of mine roadway,rock burst tests under different water saturation are carried out on the monzogranite from Huangtuliang gold mine in Northwest Hebei.The results show that with the increase of water saturation,the strength,energy storage coefficient and energy release coefficient of granite gradually decrease,and the rock burst tendency gradually decreases.When the water saturation is 0~0.4,the rock burst tendency is greatly affected by water saturation,and when the water saturation is greater than 0.4,the rock burst tendency is less affected by water saturation;in the stage of compaction and elastic deformation,AE shows"low frequency and low energy";in the stage of yield deformation,AE shows"low frequency and high energy";in the stage of rock burst,AE shows"high frequency and high energy";in the stage of yield deformation,AE will appear a period of"silent period";the cumulative number of AE events decreases with the increase of water saturation.When the water saturation exceeds 0.4,the cumulative number of AE events decreases in a cliff style,indicating that the severity of rock burst decreases significantly when the water saturation exceeds 0.4;the fractal dimension shows the evolution characteristics of"oscillation-slight decrease-sharp decrease-rise".The rapid decline of fractal dimension can be used as the precursor of granite rock burst.The research results can provide some reference for rock burst prediction of surrounding rock and water prevention measures in metal mines.
作者
徐保林
朱双云
张书杰
Xu Baolin;Zhu Shuangyun;Zhang Shujie(Zhongnan Survey Foundation Engineering Co.,Ltd.,Wuhan 430081,China)
出处
《工程勘察》
2025年第4期36-42,共7页
Geotechnical Investigation & Surveying
关键词
二长花岗岩
饱水度
岩爆倾向性
声发射
分形维数
monzogranite
water saturation
rock burst tendency
acoustic emission
fractal dimension
