Risk-Based Models for Infrastructure Asset Management

与其他工业化国家一样，加拿大在20世纪花了很大一部分时间来建设现代基础设施系统，如发电厂、管道、电力网络、桥梁、供水和废物处理系统。这些技术先进的基础设施系统提高了生产率和繁荣程度，并使加拿大的生活质量达到了前所未有的水平。在新建筑时代，主流研究人员致力于开发机械模型、设计标准和施工技术。 然而，在21世纪，新出现的挑战是如何管理陈旧基础设施系统的安全和可靠性，因为由于所需资源过多，不可能立即更换或翻新这些系统。在没有及时缓解恶化的情况下，失败的风险必然会增加，拉瓦尔的一座立交桥(2006年9月30日)和蒙特利尔的一条隧道(2011年8月1日)就是明证。因此，安全管理不仅需要对劣化的准确预测，还需要对维修保养行动的及时投入。此外，谨慎的业务管理和危险预测也同样重要。最近在Lac-Megantic发生的火车事故(2013年7月6日)表明，需要通过对基础设施系统的仔细运营管理来将风险降至最低。此外，2011年3月福岛地震摧毁了一座核电站和许多其他建筑，突显了准确估计极端危险的必要性。 因此，基础设施的退化加上极端事件(雨、洪水、风和冰暴)频率的增加，正在成为对加拿大经济发展和生活质量的威胁。因此，在对新出现的风险进行高质量评估的支持下，基础设施资产的经济生命周期管理是拟议的研究方案中要进行的一个关键研究领域。 管理结构安全的核心是预测退化的能力，这是一个本质上随机的过程，受到时间和抽样不确定性的影响。例如，即使在受控的实验室测试中，导致部件突然失效的应力腐蚀开裂和疲劳也具有很大的不确定性。拟议的研究将对这种退化机制进行全面的概率建模。这项工作将与生命周期管理相结合，以优化检查、维护和翻新计划。 -- 总而言之，该研究计划的下一个五年阶段将继续在先前研究工作成功的基础上，发现新的方法和工具，用于基础设施的高级风险分析和管理，从而促进加拿大社会的安全、经济发展和生活质量。

Canada, like other industrialized nations, devoted a large part of the 20th century into building modern infrastructure systems, such as power plants, pipelines, electrical networks, bridges, water distribution and waste-disposal systems. These technologically advanced infrastructure systems boosted productivity and prosperity, and led to an unprecedented level of quality of life in Canada. In the era of new-build, mainstream researchers focused on developing mechanistic models, design standards and construction technology. In the 21st century, however, the emerging challenge is how to manage the safety and reliability of the aged infrastructure systems, given that their immediate replacement or refurbishment is not possible due to the inordinate amount of required resources. In the absence of timely mitigation of deterioration, the risk of failures is bound to increase, as evidenced by the collapse of an overpass in Laval (September 30th, 2006) and a tunnel in Montreal (August 1, 2011). Therefore, safety management requires not only on an accurate prediction of deterioration, but also a timely investment in repair and maintenance actions. In addition, prudent operational management and prediction of hazards are equally important. The recent train disaster (July 6, 2013) in Lac-Megantic illustrates the need for minimizing risks through careful operational management of infrastructure systems. Furthermore, the Fukushima earthquake in March 2011 that destroyed a nuclear power plant and many other structures, underscores the need for accurate estimation of extreme hazards.  Thus, the degraded infrastructure combined with the increased frequency of extreme events (rain, flood, wind and ice storms) is emerging as a threat to the economic development and quality of life in Canada. As a result, the economic life cycle management of infrastructure assets supported by high quality assessment of emerging risks is a critical area of research that is to be undertaken in the proposed research program.. At the core of managing structural safety is the ability to predict degradation, which is an intrinsically random process marred with temporal and sampling uncertainties. For example, stress corrosion cracking and fatigue causing the sudden failure of components are known to exhibit large uncertainties even in controlled laboratory tests. The proposed research will undertake comprehensive probabilistic modeling of such degradation mechanisms. This work will be integrated with an life cycle management to optimize the inspection, maintenance and refurbishment programs.    In summary, the next five year phase of this research program will continue to build on the success of the previous research work and discover new methods and tools for advanced risk analysis and management of infrastructure that will foster the safety, economic development, and quality of life in the Canadian society.