Acoustic emissions have been widely used as a means to investigate the damage state of concrete structures. While successful applications have regarded the localisation of cracks, quantification of the damage and safety margin estimation have been elusive because the main approaches are mostly based on empirical observations. In this work, a methodology for the numerical simulation of acoustic emission events in reinforced concrete structures is proposed with the aim of filling this gap. It relies on a numerical model for reinforced concrete structures at the macro-scale which simulates the mechanical cyclic behaviour of the structure. Analysis of the stress and strain states in the numerical model provides the basis for the simulation of the occurrence and quantification of the events. A simple attenuation law is then used to estimate the acoustic event intensity recorded by the sensors. Application to a four-point bending test on a reinforced concrete beam confirms the capability of the model to reproduce the data recorded during the test, including the Felicity effect and the cumulative intensity curve. This could potentially open the path to a more quantitative use of acoustic emission data for structural assessment of reinforced concrete structures, directly linking mechanical models and acoustic observations.

中文翻译：

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基于宏观尺度有限元建模的钢筋混凝土结构声发射活动数值模拟

声发射已被广泛用作研究混凝土结构损坏状态的一种手段。虽然成功的应用已经考虑了裂缝的定位，但由于主要方法主要基于经验观察，因此无法量化损坏和安全裕度估计。在这项工作中，提出了一种钢筋混凝土结构声发射事件的数值模拟方法，旨在填补这一空白。它依赖于宏观尺度的钢筋混凝土结构数值模型，该模型模拟结构的机械循环行为。数值模型中应力和应变状态的分析为模拟事件的发生和量化提供了基础。然后使用简单的衰减定律来估计传感器记录的声事件强度。应用于钢筋混凝土梁的四点弯曲测试证实了该模型能够重现测试期间记录的数据，包括 Felicity 效应和累积强度曲线。这可能为更定量地使用声发射数据进行钢筋混凝土结构的结构评估开辟道路，直接将力学模型和声学观测联系起来。