Structural Health Monitoring of Reinforced Concrete Structures with Advanced Concrete Mixtures

钢筋混凝土结构的结构性能和健康评估是结构设计使用年限内的一项基本要求，特别是当它们是用相对较新的混凝土混合料建造的时候。声发射监测是一项成熟的技术，已成功地应用于混凝土结构的无损检测。该方法在混凝土材料/结构在不同损伤机制下的早期损伤预测/诊断中显示了其有效性。然而，将声发射方法应用于连续结构健康监测(SHM)系统的可行性还需要更好的理解和进一步的发展。当监测具有不同混凝土材料的结构时，这一点尤其重要，这些混凝土材料可能导致不同的波传播特性，从而影响声发射数据。声发射监测对载荷条件变化和温湿度变化的敏感性也需要进一步研究。*有关混凝土结构在不同荷载和风化条件下的声发射监测的文献资料非常有限，特别是在研究先进混凝土混合料的情况下。提出的研究计划旨在利用基于声发射技术的结构健康监测系统来评估用现代发展的混凝土混合料建造的钢筋混凝土结构在各种荷载条件下的短期和长期性能。本研究项目中开发的混凝土混合料将包括纤维增强轻质自固结混凝土(FRLWSCC)、自固结橡胶混凝土(SCRC)和纤维增强自固结橡胶混凝土(FRSCRC)。本研究将检验和量化不同混凝土类型、配合比、加载类型、传感器位置和试件尺寸对钢筋混凝土构件连续自振模声发射数据的影响。还将考察不同的温度/湿度对所产生的混合物的性能的影响以及相应的声发射信号。这项研究将解决先进混凝土混合料开发中的重要差距，并将有助于改进声发射监测。该研究还将为HQP在基础研究和应用研究方面的培训提供独特的环境。这项研究的结果将有助于建立声发射监测和先进混凝土技术的知识体系。该项目的成果将通过延长设施的运行寿命和提高混凝土结构的安全和设计效率来增加加拿大的技术开发和设计能力。

Structural performance and health assessment of reinforced concrete structures is an essential requirement throughout the designed service lifetime of the structures, especially when they are constructed with relatively new concrete mixtures. Acoustic emission (AE) monitoring is a well-established technique that has been successfully employed in the non-destructive assessment of concrete structures. This method has shown its effectiveness in early damage prognosis/diagnosis in concrete materials/structures exposed to various damage mechanisms. However, the feasibility of using AE methodology in continuous structural health monitoring (SHM) systems needs better understanding and further development. This is particularly important when monitoring structures with variable concrete materials that can lead to different wave propagation characteristics and consequently affect the AE data. The sensitivity of AE monitoring to the changes in loading conditions and temperature/humidity variations also requires further investigation. ***There is very limited information available in the literature regarding AE monitoring in concrete structures subjected to different loading and weathering conditions, especially when advanced concrete mixtures are investigated. The proposed research program aims to utilize an SHM system based on AE techniques to evaluate the short- and long-term performance of reinforced concrete structures constructed with modern developed concrete mixtures under a variety of loading conditions. The developed concrete mixtures in this research program will include fibre-reinforced lightweight self-consolidating concrete (FRLWSCC), self-consolidating rubberized concrete (SCRC), and fibre-reinforced self-consolidating rubberized concrete (FRSCRC). The impact of different concrete types, mixture proportions, loading types, sensor locations, and specimen sizes on the collected AE data from continuous SHM of reinforced concrete elements will be examined and quantified in this research. The influence of varying temperature/humidity on the performance of the produced mixtures and the corresponding AE signals will also be examined. The research will address important gaps in the development of advanced concrete mixtures and will contribute to the improvement of AE monitoring. The research will also provide a unique environment for training of HQP in fundamental and applied research. The results of this research will contribute to the body of knowledge of both AE monitoring and advanced concrete technology. The outcomes of this project will increase the technology development and design capability in Canada by extending the facility operating lifetime and improving the safe and design efficiency of concrete structures.