Performance-based design of bridge retrofitting with novel techniques considering life-cycle analysis

加拿大的桥梁库存中有很大一部分已经超过或即将结束使用寿命。这种桥梁倒塌的风险很高，特别是在易发生极端自然事件的地区，极端自然事件在很大程度上是由于气候变化的影响而变得更加频繁。放弃大桥(完全或部分关闭，限制进入)将严重影响一个地区的运营。用新的结构替换有缺陷的桥梁将需要大量投资，还会产生大量的碳排放。因此，改装将是降低风险的更安全的方法。有限的财政资源，加上加拿大有缺陷的桥梁不断急剧增加，要求采取大胆的行动，只有通过系统、精心设计和可实施的研究才能实现这一目标。拟议的学术-产业合作通过两个轨道解决上述挑战。第一个重点是制定一个系统的程序，使用基于性能的原则来确定需要评估抗震加固的桥梁并确定其优先顺序。第二条轨道的重点是采用创新的具有成本效益的桥梁翻新和维修措施，并通过整合生命周期和生命周期成本分析制定基于性能的设计准则。该项目的第一阶段将处理所有公有桥梁的清单。根据数据库中的数据，将使用基于性能的评估对桥梁状况进行详细评估。在下一阶段，创新的桥梁改造/修复措施的前景将通过实验计划和广泛的数值模拟相结合的方式进行评估。将制定综合生命周期成本和以绩效为基础的设计准则，以确保拟议的新措施在实践中可实施。研究小组将与设计规范委员会密切合作，制定适当的框架，以便将拟议的设计建议和准则纳入设计规范。

A large portion of the bridge inventory in Canada has either passed or is approaching its end of service life. Such bridges are at high risk of collapse especially in regions prone to extreme natural events, which are becoming more frequent in large part due to the influence of climate change. Abandoning the bridge (total or partial closure with restricted access) will significantly affect the operation of a region. Replacing deficient bridges with new structures would require substantial investment and also impose significant carbon emission. Hence, retrofitting would be the safer method of mitigating risks. The limited financial resources coupled with the continuous drastic increase of deficient bridges in Canada calls for bold actions which can only be achieved through systematic, well-designed, and implementable research. The proposed academic-industrial collaboration addresses the above challenges through two tracks. The first one focuses on developing a systematic procedure that uses performance-based principles to identify and prioritize bridges that need to be evaluated for seismic retrofitting. The second track focuses on introducing innovative cost-effective bridge retrofit and repair measures and the development of performance-based design guidelines by integrating lifecycle and lifecycle cost analysis. The first phase of this project will deal with the inventory of all publicly owned bridges. Based on the data in the database, detailed evaluations of the bridge conditions will be performed using performance-based assessment. In the next phase, the prospect of innovative bridge retrofitting/repairing measures will be evaluated by a combination of experimental programs and extensive numerical simulations. Integrated lifecycle cost and performance-based design guidelines will be developed to ensure that the proposed novel measures are implementable in practice. The research team will work closely with the design code committee to formulate the appropriate framework with which the proposed design recommendations and guidelines can be incorporated into the design codes.