基于小波变换的含水岩石损伤破坏过程声发射特征研究

项目名称： 基于小波变换的含水岩石损伤破坏过程声发射特征研究

项目编号： No.51204029

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 冶金与矿业学科

项目作者： 康玉梅

作者单位： 东北大学

项目金额： 25万元

中文摘要： 地下水是影响岩体流变及工程稳定性的重要因素。水的存在，使声发射信号变得更加复杂，如何对声发射信号进行全面、合理而有效的解读，并基于此对岩石进行损伤评价，是声发射技术应用于岩体损伤监测的瓶颈问题。本课题以含水岩石受载后的声发射特征为研究目标，首先，在含水岩石破裂过程声发射试验的基础上，探讨不同含水量岩样破坏过程声发射时空演化规律；其次，以小波变换为手段，对含水岩石声发射信号进行时频能量分析，提取声发射信号的频带能量特征，并建立声发射参数与损伤变量的对应关系，表征不同含水量对岩石损伤模式的影响；再次，对含水岩石声发射信号能量的时间序列进行小波奇异性检测，捕捉岩石破裂前兆信息；最后，将前述研究规律和方法应用于分析不同含水区域岩体的微震监测信息，并据此为岩体的稳定性提出建议。本课题将为借助于声发射监测技术实现含水裂隙岩体的损伤与破坏预测奠定理论基础。

中文关键词： 岩石声发射；含水量；小波变换；损伤表征；破坏过程

英文摘要： The underground water plays an important role in controlling the rheology and stability of rock mass engineering. The existence of water increases the complexity of acoustic emission signals of rock. Therefore, the comprehensive, reasonable and valid interpretation of acoustic emission signals and its application in the damage evaluation of the rock is the bottleneck problem in monitoring the damage of rock mass by the acoustic emission technique. This project will focus on the impact mechanism of the water on the acoustic emission signals of water-bearing rock. Firstly, the Spatial and temporal evolution of acoustic emission during the failure process of rock samples with different water content, will be explored on the basis of the laboratory tests. Secondly, the wavelet transform will be applied in the analysis of the acoustic emission signals of water-bearing rock, including the analysis of time-frequency energy and the estimation of time-varying power spectrum, extraction of frequency band energy feature of acoustic emission signals, the establishment of the corresponding relationship between acoustic emission parameters and damage variables, and characterization of the damage model of water-bearing rock. Thirdly, wavelet singularity will be detected for time series of acoustic emission energy, and the fail

英文关键词： rock acoustic emission；water content；wavelet transform；damage characterization；failure process