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Recognizing the need to adapt our new and existing infrastructure and operation procedures to withstand increased climatic loads and degradation mechanisms, the National Research Council Canada (NRC) has been collaborating with Infrastructure Canada to develop and revise codes, specifications, guidelines and assessment tools to advance adaptation solutions for Canadian infrastructure since 2016. Phase 1 of the Climate Resilient Buildings and Core Public Infrastructure (CRBCPI) initiative was undertaken at the NRC between 2016 and 2021 to integrate climate resilience into building and infrastructure design, guides, standards and codes. The target infrastructure types for the CRBCPI initiative included buildings, bridges, roads, rail, transit, and water and wastewater systems. In 2021, the NRC received approval to proceed with Phase 2 of the initiative, the Climate Resilient Built Environment (CRBE). In addition to the previously mentioned infrastructure types, dams are included in the scope of the CRBE initiative. Dams retain enormous amounts of water and are designed to resist hydraulic loads, therefore, it is expected that factors related to climate change that affect water flow will also affect dams. Unexpected interruptions in dam operations may lead to significant economic loss, while dam failures may be catastrophic. Historically, dam design, construction and operation have been carried out assuming stationary climatic and non-climatic conditions. In today's changing climate, the assumptions of stationary climatic baselines may no longer be appropriate for long-term dam design and operations. The CRBE's Climate Resilient Dams (CRD) theme will focus on the development of technologies, procedures and guidelines for the adaptation of publicly-owned water dams to mitigate the adverse effects of a changing climate. It should be noted that tailing and mining dams are not included in the scope of the CRD project. Water dams in Canada are owned by various entities such as federal and provincial governments, utilities and municipalities, agricultural districts, private organizations, and individuals. Canada does not have a federal regulatory agency or a unified program to guide the development of requirements for the safe management of dams. None of the provinces and territories had any specific legislation on dam safety until 1978 when the Province of Alberta established the first dam safety regulatory program in response to concerns due to a number of dam failures around the world. The main purpose of current dam safety regulations is to ensure that dams and their appurtenant and hydraulic structures are designed, constructed, maintained, operated and decommissioned with the best available technology and best practices. It should be noted that none of the dam safety regulations reviewed within the scope of this project took into consideration or directly mentioned climate change. In order to address this gap, the objectives of this project are: (1) to identify knowledge gaps in the adaptation of Canadian dams to climate change; and (2) to develop future research directions for the NRC’s Construction Research Centre in the areas of climatic data requirements, operations, water quality, monitoring, geotechnical/structural aspects and material durability.

Many bridges around the world are in urgent need of refurbishment and face challenges of limited capital investment and condition assessment. Public transportation agencies need reliable monitoring technologies to provide advance warnings of performance loss and pending failure of their critical assets, probability of which may increase due to climate change and extreme weather events. Satellites can be used to address some of these issues by taking several images of a bridge structure at different times and analyzing them with advanced processing techniques such as Interferometric Synthetic Aperture Radar (InSAR). With this approach, accurate weather-independent displacement measurements can be obtained to complement scheduled visual inspection data for bridge performance assessment. This paper presents the InSAR methodology with application to a major bridge in Montreal, Canada, namely the historic Victoria Bridge over which acquired satellite images have been validated against analytical and numerical predictions. A new calculation methodology is presented for the validation of satellite displacement measurements and their comparison to predefined thresholds in order to identify the extent and location of excessive motion on the bridge structure. The displacement results of interest include linear rate (or velocity) and thermal sensitivity (or thermal expansion rate), where both, taken separately or in combination, are found valuable for an accurate assessment of the bridge structural integrity. Finally, a new software platform called BRIGITAL is presented, which can make use of satellite data for 3D visualization, data analysis, and detection and early warning of excessive bridge displacements, which can help bridge engineers identify hot spots on bridges and take action to avoid possible problems and failures., 10th International Conference on Structural Health Monitoring of Intelligent Infrastructure, SHMII 2021, June 30 - July 2, 2021, Porto, Portugal

Canada’s buildings, bridges, roads, rail transit, potable water systems and wastewater systems provide shelter and safe drinking water, enable transport of people and goods, and collect and treat wastewater. They provide basic and core services for Canadians and are critical to Canada’s economy and the nation’s quality of life. These buildings and core public infrastructure (B&CPI) are subject to time-varying and uncertain effects due to climate change, as well as more frequent extreme weather events, such as flooding. These climate changeinduced pressures could potentially reduce the safety, serviceability, functionality, and service life of Canada’s B&CPI. In addition, Canadian B&CPI are aging and deteriorating due to different degradation mechanisms, as well as inadequate inspection and maintenance practices – issues potentially made worse by the effects of climate change. The Climate-Resilient Buildings and Core Public Infrastructure (CRBCPI) initiative was established as a research and development partnership between the National Research Council of Canada (NRC) and Infrastructure Canada to develop new and revised codes, standards, specifications, guidelines and decision support tools to ensure that Canada’s new and existing B&CPI are more resilient to the effects of climate change and extreme weather events. Funded by Infrastructure Canada and managed by NRC, the effort brings together experts from across Canada. Initiative priority areas include buildings, bridges, roads, potable water, storm water, and wastewater systems, and rail transit guideways. The initiative addresses resilience to climate change impacts on temperature, precipitation, wind and extreme weather events, including flooding, wildfires and extreme wind, which can affect these types of B&CPI across the country.

Les bâtiments, les ponts, les routes, le transport en commun sur rail de même que les réseaux d'alimentation en eau potable et d'évacuation des eaux usées du Canada fournissent un abri et de l'eau potable, et permettent le transport des personnes et des marchandises ainsi que la collecte et le traitement des eaux usées. Ils fournissent des services de base essentiels aux Canadiens et sont d'une importance cruciale pour l'économie canadienne et la qualité de vie de la nation. Ces bâtiments et infrastructures publiques de base (BIPB) subissent des effets incertains et variables dans le temps en raison des changements climatiques, et sont soumis à des événements météorologiques extrêmes plus fréquents, comme les inondations. Ces pressions induites par les changements climatiques pourraient éventuellement réduire la sécurité, le rendement en service, la fonctionnalité et la durée de vie des BIPB du Canada. De plus, les BIPB canadiens vieillissent et se détériorent en raison de différents mécanismes de dégradation, ainsi que de pratiques inadéquates d'inspection et d'entretien – des problèmes potentiellement aggravés par les effets des changements climatiques. L'initiative Bâtiments et infrastructures publiques de base résilients aux changements climatiques (BIPBRCC) a été établie sous forme de partenariat de recherche-développement entre le Conseil national de recherches du Canada (CNRC) et Infrastructure Canada afin d'élaborer des codes, des normes, des spécifications, des lignes directrices et des outils décisionnels nouveaux et révisés pour rendre les BIPB nouveaux et existants au Canada plus résilients face aux effets des changements climatiques et des événements météorologiques extrêmes. Financée par Infrastructure Canada et gérée par le CNRC, cette initiative réunit des experts de partout au pays. Les secteurs prioritaires de l'initiative comprennent les bâtiments, les ponts, les routes, les réseaux d'eau potable, d'eaux pluviales et d'eaux usées, ainsi que les transports en commun sur rail. L'initiative porte sur la résilience face aux impacts des changements climatiques sur la température, les précipitations, le vent et les événements météorologiques extrêmes, notamment les inondations, les incendies de forêt et le vent extrême, qui peuvent affecter ces types de BIPB partout au pays.

A review of previous experimental, analytical, and numerical research conducted on pipe segments subjected to combined loading indicate that very few tests were reported on (a) pipes subject to load combinations involving axial tension, internal pressure, and bending, and (b) tests involving combinations of torsion, internal pressure, and bending. Within this context, an experimental program consisting of two full-scale test series on a total of eight pipe specimens is conducted. The specimens were made of X65 material (Specified Minimum Yield Strength=448MPa) with 508mm outer diameter (OD), and a nominal diameter-to-thickness ratio (D/t) of 80. In the first test series, specimens were subjected to combinations of internal pressure, axial tension, and bending and were aimed at (a) quantify the beneficial effect of axial tension on the magnitude of critical buckling strains of pipes and (b) determine whether or not the pipes are able to attain their modified plastic moment resistance as predicted by analytically derived plastic interaction relations. In the second test series, pipe specimens were subjected to load combinations involving internal pressure, axial tension, torsion, shear, and bending and were aimed to measure the pipe modified moment capacity. The moment vs. curvature relations, peak moment values, and local buckling behavior of the specimens as obtained from the experiments are documented. The peak moments obtained are compared to the analytically predicted moments. A nonlinear shell finite element model is also developed using the Finite Element Analysis (FEA) simulator ABAQUS in order to predict the moment capacity, critical strains, and the local buckling behavior of pipe specimens. Test results were observed to compare very well with FEA predictions for the moment capacities and buckling modes. Under certain combinations of axial tension and internal pressure, experiments and FEA show that pipes with Dt=80 are able to attain their modified plastic moment resistances. The FEA predicted longitudinal compressive strains were fairly good, but less reliable than the FEA predicted moment resistances. After demonstrating the ability of the FEA to reliably predict pipe modified moment capacity in previous and current research programs, a systematic FEA parametric study is conducted to investigate the effect of geometric properties (D/t) and loading conditions (torsion, axial force, and internal pressure) on the ability of the pipes to develop their modified plastic moment capacity. As a result of this parametric study, it was observed that the ability of the pipes to develop their plastic moment capacity is strongly dependant on axial force and D/t ratio. On the other hand, internal pressure and torsion are relatively less effective on this ability.

The first part of this study reports an experimental program consisting of six full-scale tests on pipe sections under load combinations of shearing forces, bending moments, and twisting moments. The experimental results agree very well with the predicted failure loads based on recently developed interaction relations. The experimental program establishes the validity of the analytical techniques used to derive the interaction relations for pipe sections. The verified methodology is extended to derive interaction relations for square hollow structural sections under combinations of normal forces, twisting moments, biaxial bending moments, and biaxial shearing forces. Careful consideration is given to the applicability limits of the developed interaction relations. A stress resultant transformation scheme is devised in order to reduce the number of interaction relations from 20 cases to only three fundamental cases.