Bridges are essential elements in the built environment since they underpin the functioning of transportation systems. Nevertheless, they are vulnerable due to aggressive environment, demand beyond the design level, and other contingencies such as extreme events. The management of bridges represents a significant challenge for improving transport performance and ensure the safety of users. In Italy, bridge management is addressed by the recent “Guidelines for risk classification and management, safety evaluation and monitoring of existing bridges” which were issued by the Italian Ministry for Public Work in 2020. The guidelines propose an operational approach with distinctive characteristics: (i) risk-based, i.e., based on the typical parameters of hazard, vulnerability, and exposure; (ii) multi-level, i.e., they include six assessment levels (0-5) of increasing complexity; and (iii) multi-risk, i.e., they assess structural/foundation, seismic, hydrological and landslide risk. This paper presents a general overview of the 2020 Italian Guidelines and their application to a selected case study. Lessons from the application to the case study are drafted and possible criticalities highlighted.@en

Housing in informal settlements often lacks construction techniques that adopt criteria of resilience to natural hazards. Smartphones are rapidly diffusing in economically developing countries. The aim of this study was to assess the current use of smartphones by the masons of the informal settlements of Iringa, Tanzania, and to identify pathways for improving their construction practices. Data were collected through a mixed method approach that includes in-depth interviews, surveys, and a focus group with masons. The results reveal that only a few masons received formal training, most of them have never interacted with a qualified engineer nor consulted trained professionals when needed. Most masons own a smartphone and they extensively use it to gather technical information from the web, transfer money through mobile payments, share images of construction details, and promote their work on social media. The broad use of smartphones shows potential for enhancing construction quality. This article presents a unique analysis of the use of smartphones in the construction of informal settlements in Tanzania, which could be extended to other countries. Based on the findings, new strategies are proposed to engage with local stakeholders and foster the exchange of technical knowledge for safer settlements via smartphones.@en

Society is dependent on aging infrastructure, which usually operates outside its expected life. Replacing this infrastructure is often an unviable option due to its cost and disruption. A structure's operational life might be extended if the features of its aging are better understood, enabling preventive maintenance to compensate. Digital Twins (the continuous comparison between sensor measurements and a mathematical model) are one way of enabling this sort of data-driven decision making. However, despite the possibilities for this technology, its take up amongst industry has been slow, in part because infrastructure managers are unsure of how the technology will support them. This work develops a methodological framework to enhance this uptake in the field of systems engineering and the system development life cycle, using the developed knowledge to inform how an operational Digital Twin should be created. The requirements capture is the most important part of any system design development process. We present a Digital Twin development method, grounded firmly in a thorough requirements capture, and illustrate how those requirements inform many of the later design decisions. We then present our method through a case study of the Clifton Suspension Bridge, UK. Our method provides a series of actionable steps, the completion of which will facilitate the creation of a Digital Twin able to support operational decisions. By fulfilling the requirements of infrastructure managers, we hope to encourage the uptake of the technology.@en

Society is dependent on aging infrastructure, which usually operates outside its expected life. Replacing this infrastructure is often an unviable option due to its cost and disruption. A structure's operational life might be extended if the features of its aging are better understood, enabling preventive maintenance to compensate. Digital Twins (the continuous comparison between sensor measurements and a mathematical model) are one way of enabling this sort of data-driven decision making. However, despite the possibilities for this technology, its take up amongst industry has been slow, in part because infrastructure managers are unsure of how the technology will support them. This work develops a methodological framework to enhance this uptake in the field of systems engineering and the system development life cycle, using the developed knowledge to inform how an operational Digital Twin should be created. The requirements capture is the most important part of any system design development process. We present a Digital Twin development method, grounded firmly in a thorough requirements capture, and illustrate how those requirements inform many of the later design decisions. We then present our method through a case study of the Clifton Suspension Bridge, UK. Our method provides a series of actionable steps, the completion of which will facilitate the creation of a Digital Twin able to support operational decisions. By fulfilling the requirements of infrastructure managers, we hope to encourage the uptake of the technology.@en

Many communities around the world are facing increasing flood-induced damage to bridges due to climate change and rising urbanisation. It is thus crucial to understand how different bridge types suffer from flooding and how this may affect surrounding networks. Despite the large body of literature for seismic and hurricane taxonomies, few classifications exist for bridges at flood risk. In this work, existing global bridge classifications were reviewed in order to derive a bridge–flood taxonomy. The review revealed that existing studies mainly classify bridges according to the superstructure material, whereas subclasses consider superstructure and substructure components. A taxonomy of 20 attributes for riverine roadway bridges susceptible to flood hazards is proposed in this paper. Its applicability for three bridge datasets in the UK was verified. The results showed that the considered datasets have data for 13 attributes, which can be used to derive regional bridge classes. In general, the taxonomy is functional for standardising different bridge datasets and applying/developing damage models for given bridge portfolios of flood-prone countries. Future works could apply the taxonomy to additional bridge datasets within a network for risk assessments; the proposed taxonomy could also be extended to allow integration with functionality and restoration models.@en

Digital Twins (DTs) are forecasted to be used in two-thirds of large industrial companies in the next decade. In the Architecture, Engineering and Construction (AEC) sector, their actual application is still largely at the prototype stage. Industry and academia are currently reconciling many competing definitions and unclear processes for developing DTs. There is a compelling need to establish DTs as practice in AEC by developing common procedures and standards tailored to the sector's procedures and use cases. This paper proposes a step-by-step workflow process for developing a DT for an existing asset in the built environment, providing a proof-of-concept case study based on the Clifton Suspension Bridge in Bristol (UK). To achieve its aim, this paper (i) reviews the state-of-the-art of DTs in Civil Engineering, (ii) proposes a working DT-based workflow framework for the built environment applicable to existing assets, (iii) applies the framework and develops of the physical-virtual architecture to a case study of bridge management, and finally (iv) discusses insights from the application. The main novelty lies in the development of a versatile methodological framework that can be applied to the broad context of civil infrastructure. This paper's importance resides in the knowledge challenge, value proposition and operation dictated by developing a DT workflow for the built environment, which ultimately represents a relevant use case for the digital transformation of national infrastructure.@en

The 2030 Sustainable Development Goals (SDGs) offer a blueprint for global peace and prosperity, while conserving natural ecosystems and resources for the planet. However, factors such as climate-induced weather extremes and other High-Impact Low-Probability (HILP) events on their own can devastate lives and livelihoods. When a pandemic affects us, as COVID-19 has, any concurrent hazards interacting with it highlight additional challenges to disaster and emergency management worldwide. Such amplified effects contribute to greater societal and environmental risks, with cross-cutting impacts and exposing inequities. Hence, understanding how a pandemic affects the management of concurrent hazards and HILP is vital in disaster risk reduction practice. This study reviews the contemporary literature and utilizes data from the Emergency Events Database (EM-DAT) to unpack how multiple extreme events have interacted with the coronavirus pandemic and affected the progress in achieving the SDGs. This study is especially urgent, given the multidimensional societal impacts of the COVID-19 pandemic amidst climate change. Results indicate that mainstreaming risk management into development planning can mitigate the adverse effects of disasters. Successes in addressing compound risks have helped us understand the value of new technologies, such as the use of drones and robots to limit human exposure. Enhancing data collection efforts to enable inclusive sentinel systems can improve surveillance and effective response to future risk challenges. Stay-at-home policies put in place during the pandemic for virus containment have highlighted the need to holistically consider the built environment and socio-economic exigencies when addressing the pandemic’s physical and mental health impacts, and could also aid in the context of increasing climate-induced extreme events. As we have seen, such policies, services, and technologies, along with good nutrition, can significantly help safeguard health and well-being in pandemic times, especially when simultaneously faced with ubiquitous climate-induced extreme events. In the final decade of SDG actions, these measures may help in efforts to “Leave No One Behind”, enhance human–environment relations, and propel society to embrace sustainable policies and lifestyles that facilitate building back better in a post-pandemic world. Concerted actions that directly target the compounding effects of different interacting hazards should be a critical priority of the Sendai Framework by 2030.@en

The conservation of cultural heritage artefacts often requires particular conditions and a bespoke setup. We investigate the use of computational fluid dynamics (CFD) modelling to obtain high-resolution data of the present setup to conserve the SS Great Britain: the first iron-hulled screw-propelled ocean-going ship, preserved in its original dry dock in Bristol (UK). The conservation efforts focus on the dry air curtain to maintain the hull at low relative humidity to prevent corrosion, hence avoiding further degradation. The proposed computational model captures the key features, enabling the study of the air curtain efficacy, retaining an overall uncomplicated setup which is seen to be robust in a sensitivity analysis. The analysis of the transport of dry air focuses on the near-wall region, hence the interface between fluid and solid surface, in which exchange of species occurs, such as humidity and temperature. The near-wall fluid dynamics is described by the wall shear stress, divergence of wall shear stress, surface shear lines and wall shear stress critical points. The results provide a complete description of the flow near the hull surface and identify regions where the air curtain maintains adequate protection. The investigation highlights the use of air curtains on solid surfaces together with the analysis techniques necessary to describe the fluid dynamics. The modelling assumptions proposed are shown to be effective in investigating the air curtain. The solution to the computational model is compared to sensor data, showing good agreement on the ship's hull.@en

On-site sanitation systems (OSS), such as pit latrines, are an important source of methane (CH4), with emissions increasing when they are wet, and this occurs when anaerobic conditions dominate. This paper presents the development of a model, which uses seasonal changes in groundwater to account for the fluctuating inundation of pit latrines, and, therefore, the associated CH4 emissions from varying degrees of anerobic conditions are examined. Given that observed timeseries of groundwater table depth at high enough spatial and temporal resolutions are often difficult to obtain in low- and middle-income countries (LMICs), inverse distance weighted (IDW) interpolation is used to generate values for a whole region, which is then used, alongside average pit latrine depth, to determine areas of pit latrine inundation. Outcomes are further informed with open-source contextual data, covering population, urban/rural split, and sanitation facility data, before using methodologies from the Intergovernmental Panel on Climate Change (IPCC) to generate CH4 emissions data. As a case study, we use data from Senegal to illustrate how this model works. Results show total CH4 emissions for the month of January to be ~1.69 kt CH4. We have also discussed the potential use of satellite remote sensing data in regions where access to historical groundwater data is limited. Understanding when the pit conditions are most likely to change could lead to incentives for better management strategies, as well as a reduction in CH4 production.@en

Hydrological hazards (“hydro-hazards”) are defined as extreme events associated with the occurrence, movement and distribution of water, specifically resulting in floods and droughts. As a result of global climate change these hazards are expected to change in the future, with areas of the globe becoming “hotspots” for the intensification of these extremes. This paper is the first global review of the state- of-the-art research on hotspots for floods and drought. The work follows a systematic literature review of published research, and analyses and categorizes the results of 122 published papers after a methodical screening process. The analysis highlighted the geographical areas where increasing hazards are anticipated (e.g., Europe for both floods and droughts), and those areas of the globe where no significant research has been published (e.g., Russia). The methods used to undertake the research are analyzed and new trends identified. Potential avenues for future research are highlighted, including the incorporation of uncertainty analyses into hydro-hazard assessments, the consideration of multi-hazards and their interconnections, and finally the consideration of dynamic vulnerability and exposure in conjunction with changing hydro-hazards to understanding future risk.@en

Digitalisation and the Internet of Things (IoT) help city councils improve services, increase productivity and reduce costs. City-scale monitoring of traffic and pollution enables the development of insights into low-air quality areas and the introduction of improvements. IoT provides a platform for the intelligent interconnection of everyday objects and has become an integral part of a citizen's life. Anyone can monitor from their fitness to the air quality of their immediate environment using everyday technologies. With caveats around privacy and accuracy, such data could even complement those collected by authorities at city-scale, for validating or improving policies. The authors explore the hierarchies of urban sensing from citizen-to city-scale, how sensing at different levels may be interlinked, and the challenges of managing the urban IoT. The authors provide examples from the UK, map the data generation processes across levels of urban hierarchies and discuss the role of emerging sociotechnical urban sensing infrastructures, that is, independent, open, and transparent capabilities that facilitate stakeholder engagement and collection and curation of grassroots data. The authors discuss how such capabilities can become a conduit for the alignment of community- and city-level action via an example of tracking the use of shared electric bicycles in Bristol, UK.@en

Scour is a major cause of bridge failure and results in significant economic losses through disruption to operation. This phenomenon naturally affects bridges with underwater foundations and is exacerbated during high river and/or turbulent flows (e.g. due to extreme events). When scour reaches the bottom of or undermines shallow foundations, it may trigger various damage mechanisms that may influence the safety of the structure and force asset managers to reduce traffic capacity. Currently, assessing risk of scour is a heuristic process, heavily reliant on qualitative approaches and expert opinion (e.g. visual inspections). These types of assessments typically suffer from insufficient knowledge of influencing factors (e.g. hydraulic parameters) and the requirement to rely on several assumptions (e.g. assumed foundation depth). As a result, current scour assessment and bridge management practices do not provide reliable solutions for addressing the potential risk of bridge failures. In this paper, cross-cutting needs and challenges related to the development of decision support tools for scour-risk management are highlighted and some preliminary results of a literature survey are reported. The review has been performed with several objectives: (i) identifying scour-risk indicators describing hydrodynamic actions and the asset condition; (ii) defining indirect and direct consequences needed to assess the risks associated to different decision alternatives related to scour management; and (iii) identifying existing approaches to scour inspections and monitoring as support tools for informed decisions. The results of this survey will serve as a base for future research aimed to develop an informed decision support tool to manage scour risk at both the bridge and at the network level.@en

Flood events are the most frequent cause of damage to infrastructure compared to any other natural hazard, and global changes (climate, socioeconomic, technological) are likely to increase this damage. Transportation infrastructure systems are responsible for moving people, goods and services, and ensuring connection within and among urban areas. A failed link in these systems can impact the community by threatening evacuation capability, recovery operations and the overall economy. Bridges are critical links in the wider urban system since they are associated with little redundancy and a high (re)construction cost. Riverine bridges are particularly prone to failure during flood events; in fact, the risks to bridges from high river flows and erosion have been recognized as crucial at global level. The interaction of flow, structure and network is complex, and not fully understood. This study aims to establish a rigorous, multiphysics modeling approach for the assessment of the hydrodynamic forces impacting inundated bridges, and the subsequent structural response, while understanding the consequences of such impact on the surrounding network. The objectives of this study are to model hydrodynamic forces as demand on the bridge structure, to advance a performance evaluation of the structure under the modeled loading, and to assess the overall impact at systemic level. The flood-prone city of Carlisle (UK) is used as a case study and a proof of concept. Implications of the hydrodynamic impact on the performance and functionality of the surrounding transport network are discussed. This research will help to fill the gap between current guidance for design and assessment of bridges within the overall transport system.@en

This article presents a methodology aimed at enhancing infrastructure resilience to extreme weather events while ensuring provision of critical services at community level. It describes critical infrastructure systems and services as features of a resilient community, considering that the accessibility to critical services is conditioned to the availability of critical infrastructure systems in different ways. The methodology is written as a mixed-integer linear programming model. The selection of appropriate planning and operational measures for resilience enhancements is made with the objective of ensuring provision of critical services under severe weather conditions subject to technical operating constraints. Furthermore, the methodology is demonstrated in a realistic setting in Stockport, UK, with an impact assessment of disruptions to power and transportation infrastructure systems caused by flooding on the provision of distinct critical services. @en

With the increase of the frequency and severity of flooding events, coupled with population growth, the risks posed to people from flooding is ever more apparent. This paper proposes a methodology to examine the risks posed to vehicles' occupants and pedestrians simultaneously in an urban context. Through considering stability functions of a range of vehicle types and pedestrian, a risk assessment profile for a vehicle occupant was derived. Using a historical 1-in-20-year rainfall flood event that took place in the city of Exeter (UK) in 2014, and a synthetic 1 in 100-year rainfall flood event, the potential risks posed to vehicle occupants were analysed. The results showed that for these events the potential risks posed to people travelling by car and caught in flood waters were likely to be more severe if they were to remain within their vehicles than if they were to exit said vehicles. Analysis of the changes in risk over time further revealed that if a vehicle was to become immobilised in flood water, they would only have a short timeframe (~10 min) before the level of risk increases. This is a critical finding, highlighting that remaining inside an immobilised vehicle during flood event and waiting for assistance may increase the level the risk the individual is exposed to, with the results showing the significance of such studies in reducing the risk of flooding to people.@en

One major issue when considering the effects of climate change is to understand, qualify and quantify how natural hazards and the changing climate will likely impact infrastructure assets and services as it strongly depends on current and future climate variability, location, asset design life, function and condition. So far, there is no well-defined and agreed performance indicator that isolates the effects of climate change for structures. Rather, one can mention some key considerations on how climate change may produce changes of vulnerability due to physical and chemical actions affecting structural durability or changes of the exposure in terms of intensity/frequency of extreme events. This paper considers these two aspects and associated challenges, considering some recent activities of members of the IABSE TG6.1.@en

One major issue when considering the effects of climate change is to understand, qualify and quantify how natural hazards and the changing climate will likely impact infrastructure assets and services as it strongly depends on current and future climate variability, location, asset design life, function and condition. So far, there is no well-defined and agreed performance indicator that isolates the effects of climate change for structures. Rather, one can mention some key considerations on how climate change may produce changes of vulnerability due to physical and chemical actions affecting structural durability or changes of the exposure in terms of intensity/frequency of extreme events. This paper considers these two aspects and associated challenges, considering some recent activities of members of the IABSE TG6.1.@en