Innovative Analytical and Experimental Techniques for Performance Assessment of Deteriorated and Repaired Reinforced Concrete Structures

在加拿大，大约三分之一的市政基础设施，估计价值3880亿美元，要么处于一般、较差的状态，要么非常差，需要修复。大多数其他国家的基础设施正经历着同样的问题，需要数千亿美元进行修复。由于各国政府目前面临严重的经济限制，迫切需要准确的绩效评估工具和有效的修复战略，以确保现有老化和恶化的基础设施的安全。 这项研究计划的目的是开发和应用创新的分析和实验技术，帮助工程师更好地了解退化和修复的钢筋混凝土(RC)结构的性能和安全性。研究计划由两个主要阶段组成。在第一阶段，将发展一种新的多平台随机分析技术，该技术能够准确评估大型复杂劣化钢筋混凝土结构的局部和整体性能，同时考虑腐蚀造成的不确定性影响。新开发的方法将用于评估现代和旧的RC桥梁结构的性能。此外，还将使用一种名为混合模拟的最先进的实验室测试方法来进一步研究劣化RC桥梁结构的系统级性能。通过将计算机建模的效率和实验室测试的准确性相结合，混合仿真可以有效地捕捉结构的系统级性能。将研究不同程度的劣化程度和配筋率对桥墩的影响。研究计划的第二阶段将集中于开发和评估使用纺织钢筋混凝土(TRC)对劣化结构进行修复的新策略。在第一阶段工作的基础上，将对一座用TRC加固的RC桥梁结构进行一系列部件级和系统级(混合模拟)测试。将对各种真相与和解委员会加强计划的效果进行评估。最后，在试验结果的基础上，建立了TRC加固钢筋混凝土柱在地震荷载作用下的三维有限元模型，并对其进行了验证。 通过这项研究计划，将开发新的性能评估工具和有效的修复策略，使工程师和决策者能够准确地决定哪些结构需要修复，以及什么是最经济有效的修复策略。这些发现将在许多重要方面使加拿大受益，例如减少极端事件后的人员和经济损失，并通过延长现有老化结构的使用寿命和减少水泥生产产生的温室气体，为可持续基础设施发展和长期经济增长做出贡献。

In Canada, about one-third of municipal infrastructure with an estimated worth of $388 billion are either in a fair, poor, or very poor condition and require rehabilitation. The infrastructure of most other countries is experiencing the same problem requiring hundreds of billions of dollars for repair. With governments currently facing severe economic constraints, there is a great need for accurate performance assessment tools and effective repair strategies to ensure the safety of existing aging and deteriorated infrastructure. The aim of this research program is to develop and employ innovative analytical and experimental techniques to help engineers gain a better insight into the performance and safety of deteriorated and repaired reinforced concrete (RC) structures. The research program is comprised of two main phases. In the first phase, a novel multi-platform stochastic analysis technique will be developed which is capable of accurately assessing both the local and global performance of large complex deteriorated RC structures, while considering the uncertainty effects due to corrosion. The newly developed method will be employed to assess the performance of both modern and old RC bridge structures. Furthermore, a state-of-the-art laboratory testing method called hybrid simulation will be used to further investigate the system-level behaviour of deteriorated RC bridge structures. By combining the efficiency of computer modelling with the accuracy of laboratory testing, hybrid simulation can effectively capture the system-level performance of structures. The influence of different levels of deterioration and reinforcement ratios in bridge piers will be investigated. The second phase of the research program will focus on the development and evaluation of a new repair strategy for deteriorated structures using textile reinforced concrete (TRC). Building upon the work carried out in phase 1, a series of component-level and system-level (hybrid simulation) tests will be conducted on an RC bridge structure strengthened with TRC. The effectiveness of various TRC strengthening schemes will be evaluated. Lastly, based on the results obtained from the experimental tests, a 3D finite element modelling method will be developed and validated for the analysis of TRC-repaired RC columns under seismic loads. Through this research program, novel performance assessment tools and effective repair strategies will be developed which enable engineers and decision makers to accurately decide which structures require rehabilitation and what would be the most economical and effective repair strategy for them. The findings will benefit Canada in many significant ways such as reducing human and economic loss following extreme events and contributing to sustainable infrastructure development and long-term economic growth by extending the service life of existing aging structures and reducing the generation of greenhouse gases from cement production.