In this work, a novel method for damage evolution analysis of concrete under uniaxial compression is proposed based on the multi-feature acoustic emission (AE) and the Gaussian mixture model (GMM) clustering. The hierarchical clustering algorithm is adopted to select optimal AE parameters, while multiple features of these parameters are generated through the principal component analysis (PCA). Then the concrete damage signals are separated by using the GMM clustering with multiple features. Meanwhile, the waveform signals associated with concrete damage in each cluster are validated using the Fast Fourier transform (FFT) and the continuous wavelet transform (CWT). Finally, the damage evolution process of concrete under uniaxial compression is divided based on the variation of AE characteristics. The results show that the frequency ranges of signals for micro-cracks, mixed cracks and friction of concrete under uniaxial compression are 20–30 kHz, 20–65 kHz, and 100–120 kHz, respectively. The damage process of concrete under uniaxial compression is divided into three stages according to the inflection points of the cumulative energy curve, namely the initial compaction stage, the crack formation stage and the failure stage.

中文翻译：

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基于多特征声发射和高斯混合模型聚类的混凝土损伤演化分析

在这项工作中，提出了一种基于多特征声发射（AE）和高斯混合模型（GMM）聚类的单轴压缩混凝土损伤演化分析的新方法。采用层次聚类算法选择最优AE参数，同时通过主成分分析（PCA）生成这些参数的多个特征。然后利用多特征GMM聚类分离混凝土损伤信号。同时，使用快速傅里叶变换（FFT）和连续小波变换（CWT）验证与每个簇中混凝土损坏相关的波形信号。最后根据声发射特性的变化划分了单轴压缩下混凝土的损伤演化过程。结果表明，单轴压缩混凝土微裂纹、混合裂纹和摩擦信号的频率范围分别为20~30 kHz、20~65 kHz和100~120 kHz。根据累积能量曲线的拐点，单轴压缩混凝土的损伤过程分为三个阶段，即初始压实阶段、裂缝形成阶段和破坏阶段。