节点文献

岩爆的能量特征实验分析

Experimental Analysis on the Energy Characteristics of Rockburst

【作者】 苗金丽

【导师】 何满潮;

【作者基本信息】 中国矿业大学(北京) , 岩土工程, 2009, 博士

【摘要】 利用真三轴岩爆过程模拟实验系统及建立的岩爆实验方法,进行了花岗岩、砂岩、石灰岩、煤等不同岩性的岩爆室内实验研究,再现了岩爆现象。从两个不同侧面分析了岩爆的能量特征,分别为基于实验过程测到的声发射释放的能量及基于形成岩爆碎屑消耗的能量。根据声发射能率及累计能量参数,系统地分析了岩爆的能量变化特征;根据声发射的频谱变化结果,分析了不同岩性主频特征;利用声发射的时频分布及微观结构扫描结果,分析了岩爆破坏过程中穿晶剪切裂纹是高能量释放型裂纹、沿晶张性裂纹是低能量释放型裂纹。对岩爆碎屑分布特征进行了研究,对不同粒组岩爆碎屑的能量耗散特征进行了初步分析。

【Abstract】 A series of lithology rockburst tests have been conducted by the true triaxial rockburst simulating test system with the new experimental approaches, including granite, sandstone, limestone and coal. The phenomenon of rockburst is reproduced in laboratory. The energy chatacteristics of rockburst were analyzed on two aspects, i.e, acoustic emission (AE) release energy and the rockburst fragments dissipate energy. The release energy characteristics of acoustic emission were investigated in details based on AE release energy ratio and AE cumulative energy. The predominant frequency of AE was identified according to the frequency spectrum results. According to the time-frequency distribution and the post-failure sample scanning electron microscope images, we observe that in most cases, the transgranulation-shear cracks are of high energy releasing and the intergranular-tensile ones are of low energy releasing. The distribution of rockburst fragments was researched and their dissipation energy characteristics were also analyzed preliminary.

节点文献中: