Performance-Based Approach for Multihazard Resilient Design of Highway Bridges

保持桥梁基础设施的安全和运行状态是大多数国家面临的重大挑战。最近，北美和世界各地发生了多座桥梁倒塌，这表明它们在不同灾害下发生故障的风险不断增加。在其使用寿命期间，桥梁必须承受多种危险，其中一些危险同时发生并产生连锁效应。极端气候和自然灾害事件很少见，而且大多是出乎意料的。这些事件不仅破坏基础设施和其他设施造成经济损失，而且对灾后响应能力产生不利影响。新西兰基督城地震、2011年日本东北地震和海啸、2018年日本台风飞燕给公路桥梁造成严重损失和破坏，震撼了国民经济。目前可用的规范和指南足以解决与弹性桥梁设计相关的个别问题，但无法解决多灾害环境（主震-余震；地震-海啸；地震-洪水）中的复杂性，这些依赖性存在于多个层面。在全球频繁发生极端自然灾害之后，人们越来越重视寻找方法，以合理的成本提高基础设施的安全性和性能，并将不良副作用降至最低。桥梁业主和设计师对此方面的浓厚兴趣导致了“多灾种设计”概念的发展。尽管在多灾害设计领域已经进行了一些实验和数值研究，但它在工程中是一个相对较新的课题，因此为未来的研究提供了相当大的空间。拟议的研究计划旨在为多灾害弹性桥梁系统开发一种基于性能的方法，以确保增强的弹性和稳健性，从而最大限度地减少多种灾害的不利社会和经济影响。这项研究将侧重于确定危害之间的协同作用，从而通过结构化设计流程实现综合多危害设计方法。成功完成拟议的研究将为实践设计工程师提供设计指南，帮助他们设计可适应独立或并发的多种危险的弹性桥梁。拟议的计划不仅将为从业者提供足够的指南和数值工具来设计和分析桥梁以应对多种危险，而且还将开发创新的智能结构组件以增强结构安全性。通过采用这种创新的智能结构组件并将其与基于性能的设计方法相结合，加拿大高速公路基础设施的弹性将得到显着提高，加拿大社区在遭受极端自然灾害时将获得经济、安全和低风险的桥梁。

Keeping bridge infrastructure in safe and operational condition is a major challenge for most countries. Recently a number of bridges have collapsed in North America and around the world, which indicates their increased risks of failure under different hazards. Over its lifetime, a bridge must withstand multiple hazards, some of which occur concurrently and have cascading effects. Extreme climate and natural hazard events are rare and occur largely unanticipated. These events not only cause economic losses by damaging infrastructure and other facilities but also adversely affect post-disaster response capability. Earthquakes in Christchurch, New Zealand, the Tohoku earthquake and tsunami of 2011 in Japan, and the most recent Typhoon Jebi of 2018 in Japan caused severe losses and damage to highway bridges that shook the national economies. Currently available codes and guidelines are adequate in addressing individual issues related to resilient bridge design, but fail in addressing the complexities in a multihazard environment (mainshock-aftershock; earthquake-tsunami; earthquake-flooding), where these dependencies exist at multiple levels. In the wake of frequent extreme natural hazards around the globe, increased emphasis has been placed on identifying methods to improve infrastructure safety and performance at reasonable costs, with minimal undesirable side effects. Strong interest from the bridge owners and designers on this aspect has led to the development of the concept of “multihazard design”. Although some experimental and numerical research has been done in the field of multihazard design, it is a relatively new topic in engineering, thus providing considerable room for future research. The proposed research program is designed to develop a performance-based approach for multihazard resilient bridge systems to ensure enhanced resilience and robustness, thus minimizing the adverse social and economic impacts of multiple hazards. This research will focus on identifying synergies between hazards that make an integrated multihazard design approach possible through a structured design process. Successful completion of the proposed research will yield design guidelines for practicing design engineers in designing resilient bridges that can accommodate independent or concurrent multiple hazards. The proposed program will not only provide adequate guidelines and numerical tools for practitioners to design and analyze bridges against multiple hazards, but also develop innovative smart structural components to enhance structural safety. By adopting and integrating such innovative smart structural components with performance based design approaches, Canada's highway infrastructure resilience will be significantly improved and Canadian communities will be provided with economical, safe, and low-risk bridges when subjected to extreme natural hazards.