Abstract Several studies have been conducted to investigate early age Portland cement hydration using acoustic emission technique, with different mechanisms attributed by different authors. In the proof-of-concept research presented in this paper, acoustic emission (AE) was employed to explore relationships between recorded signals associated with elastic stress waves and potential mechanisms associated with cement hydration. Ordinary Portland cement paste samples having water/cement ratio of 0.3 and 0.5 were monitored during the first 72 h of curing using broadband AE sensors. The acoustic emission signals were analyzed using unsupervised and supervised pattern recognition algorithms to address limitations of acoustic emission parameter analysis. Wavelet analysis was utilized as a complementary method, which can be considered as a map for identification of patterns in the signal set. Unsupervised methods are useful when there is no history or background data concerning the pattern of a phenomenon such as the hydration process.

中文翻译：

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波特兰水泥浆早期水化过程中声发射信号的无监督和监督模式识别

摘要 使用声发射技术研究早期波特兰水泥水化已经进行了几项研究，不同的作者归因于不同的机制。在本文提出的概念验证研究中，采用声发射 (AE) 来探索与弹性应力波相关的记录信号与与水泥水化相关的潜在机制之间的关系。在固化的前 72 小时期间，使用宽带 AE 传感器监测水灰比为 0.3 和 0.5 的普通波特兰水泥浆样品。使用无监督和有监督的模式识别算法分析声发射信号，以解决声发射参数分析的局限性。小波分析被用作补充方法，可以将其视为用于识别信号集中模式的映射。当没有关于水化过程等现象模式的历史或背景数据时，无监督方法很有用。