矿山松散介质堆积体滑移及失稳破坏的声发射特性研究

Waste dump and tailings pond are both loose medium accumulation. The instability of accumulation deposit will induce great safety accidents. So the monitoring and prediction for its stability have an important practical and theoretical significance. At present various deformation measurements are used as a main method for stability monitoring, but the process of slide among particles and instability can not be revealed. So the effective quantitative criterion has not been established and it becomes the key problem. The project will apply acoustic emission(AE) technology to the prediction of instability of loose medium accumulation deposit. The comprehensive researches including acoustic emission test and theoretical analysis of evolution process of silde to instability of losse medium accumulation deposit will be carried out. First, the characteristics about the AE parameters, frequency, wave pattern etc. with the process of slide to instability of loose medium accumulation deposit will be obtained by lab tests. Second, space-time evolution rules from slide to instability of loose medium accumulation deposit will be acquired by AE source location test.Based on researches mentioned above we will reveal the mechanism of slide to instability of loose medium accumulation deposit and determine the corresponding criterion of instability. Achievements not only have an important theoretical value but also provide scientific basis for prediction of instability of loose medium accumulation deposit.

矿山排土场、尾矿库为松散介质堆积体，堆积体的失稳破坏将造成重大安全事故，其稳定性监测、预测具有十分重要的理论和现实意义。目前，排土场、尾矿库稳定性监测主要采用变形监测，无法反映松散介质体内部滑移、失稳过程，致使失稳破坏预测尚未有有效的定量判据，成为急需解决的难点、热点问题。本项目根据松散介质颗粒间滑移产生声发射现象的原理，拟将声发射技术引入到松散介质堆积体失稳预测中，进行松散介质堆积体失稳过程声发射试验、理论研究，通过试验得到松散介质堆积体颗粒滑移至失稳过程的声发射参数、频率和波形等特征，采用声发射定位试验分析松散介质堆积体失稳演化过程，在上述研究基础上，揭示松散介质颗粒间滑动至宏观失稳的机理，寻求松散介质堆积体失稳声发射判据，研究成果具有重要的理论价值，同时为松散介质堆积体失稳声发射预测提供重要的科学依据。

矿山排土场、尾矿库为松散介质堆积体，其失稳破坏的监测、预测具有十分重要的理论和现实意义。本项目根据松散介质颗粒间滑移产生声发射现象的原理出发，提出了将声发射技术引入到松散介质堆积体失稳预测中，通过建立的模型开展了松散介质堆积体失稳过程声发射试验，研究得到了波导杆参数，滑坡过程的声发射参数、频率和波形等特征，得到了滑坡前，声发射现象不明显，且基本参数量值较小，临近滑坡时，参数急剧增长，随后下降的规律；发现了声发射参数分形维数在临近滑移阶段出现最大值，并且之后会突然出现突降现象；与岩石不同，散体介质临近滑坡时r值下降，说明大量散体挤压能量占了主要部分，声发射事件率增加。滑坡前，小能量为主。这些可作为散体介质失稳声发射监测、预测的判据。边坡滑坡的导波声发射研究表明，对于剪切破坏，声发射事件率表现为突增后又骤降时再突增；对于弯曲破坏，声发射事件率急剧增大之后起伏变化。对于边坡失稳，临近滑移阶段附近时，声发射参数分形维数达到最大值；大规模滑移，分形维数又出现突降。为排土场边坡失稳破坏的前兆信息，同时，声发射累计事件数与累计能量比值剧减过程也是边坡失稳破坏的前兆。基于导波理论，根据同一个声发射源中不同频率成分的波到达传感器的时差，进行波导杆声发射的源定位，计算的出的声发射源位置大致位于破裂面附近，能够为处理为复杂的声发射信号进行源定位提供一定理论指导和现实依据。研究成果将声发射技术推广到散体介质破坏失稳监测、预测领域，拓展了声发射技术的应用领域，同时也为解决类似工程问题提供了必要的科学依据。