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Water distribution network (WDN) is critical to the city service, economic rehabilitation, public health, and safety. Reconstructing the WDN to improve its resilience in seismic disaster is an important and ongoing issue. Although a considerable body of research has examined the effects of different reconstruction strategies on seismic resistance,...
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... In the literature, diverse metrics and approaches have been explored to evaluate the resilience of WDNs (Christodoulou et al., 2017;Cimellaro et al., 2016;Zhao et al., 2015). While some works offer insights into minimizing network disruptions during large-scale cascade failures such as natural disasters (McAllister, 2015;Chang and Shinozuka, 2004), they focus predominantly on evaluating resilience rather than providing preventive design solutions. ...
... Shi P and O'Rourke TD (2008) investigated the types of pipe damage and provided an accurate model of pipe failure mechanism for the Los Angeles City WDN using GIRAFFE software. Zhao et al. (2015) compared the effectiveness of two resilience-based seismic strategies. They studied the different resilience enhancing strategies for municipal pipe network. ...
Seismic resilience of Sadra City water distribution network (WDN) is assessed. Complex networks theory is applied to model the WDN. Two hydraulic resilience indices including the population impacted (PI) and the water services availability (WSA) are employed. Nine scenarios considering the different earthquake intensities and epicenters are considered. The robust repair strategy is proposed considering two different perspectives, the maximum PI and WDN recovery time. Based on hydraulic resilience indices, north of Sadra City is the most vulnerable area and the network resilience is the highest in the south. Finally, employing fragility curve analysis, pipes with high probability of damage are detected to be enhanced to increase WDN resilience upon future disasters. The perspective of the WDN capacity to return to normal condition after the shock to the system is studied based on the concept of recovery time. The recovery time of the system in each scenario depicted significant correlation with the hydraulic indices.
... These metrics reflect different perspectives of various stakeholders and may not yield congruent results when applied to the assessment of the integrated WPS resilience. Examples of these metrics include: (1) time-based system metrics that utilize the area of the DIRE curve to quantify the absolute resilience of the system with respect to each resilience phase (e.g., pre-event, outage, restoration) [24]; these metrics have been tested in a number of infrastructure systems including water distribution systems [29][30][31][32][33], wastewater treatment systems [34][35][36][37], and power systems [20,[38][39][40] ; (2) graph theory-based metrics (also referred to as network or topology metrics) that incorporate the system's topology such as the number of nodes and arcs, the average degree of nodes, and the average critical path length [41,42]; (3) probabilistic-based metrics that incorporate the impacts of uncertainties (e.g., component failure) on a system's performance [40,43,44]; and (4) cost-based metrics that quantify resilience based on costs associated with recovering system performance or lost opportunity costs due to system outages [38,45]. Performance measures used in this context are based on asset operability, network connectivity, network capacity, satisfied demand, and the value of services provided [46]. ...
As increasing pressures of population growth and climate change arise, water and power systems (WPS) are becoming increasingly interdependent. This interdependency has resulted in an increased potential for cascading failures, whereby the service interruption of one system can propagate to interdependent ones. This paper makes four contributions. First, we present an extensive literature review in the field of integrated water and power resilience, leveraging both institutional and technical literature research landscapes. We compare various modeling approaches used to model interdependent WPS and discuss the different metrics and definitions that are typically employed to quantify and define resilience. Relevant challenges and gaps related to modeling tools and metrics are also discussed, and appropriate recommendations are made. Second, the paper presents a visualization prototype for interdependent WPS to showcase water and power system interdependencies and reveal co-managed resilience strategies that can be used to improve resilience under different types of common threats. Third, we provide a conceptual decision support framework that simultaneously optimizes a portfolio of co-managed resilience strategies in the face of multiple, uncertain threats and addresses WPS interdependencies. Finally, we present future trends regarding digitalization, integrated planning, collaborative governance, and equity needs for building more resilient WPS.
... They considered only one rehabilitation method, replacement, and analyzed one single failure. Other researchers focused on improving resilience of WDNs against seismic hazards (e.g., Zhao et al. 2015;. considered two main rehabilitation actions, relining and replacement, to enhance the resilience of WDNs to seismic hazards. ...
... However, the analysis was limited to 1 year, without considering the effect of deterioration and life-cycle cost on the rehabilitation planning decisions. Zhao et al. (2015) compared the effects of two strategies for enhancing the resilience of WDNs. They analyzed the impact of ductile retrofitting and meshed expansion on the seismic resilience of an actual WDN in China. ...
... They considered only one rehabilitation method, replacement, and analyzed one single failure. Other researchers focused on improving resilience of WDNs against seismic hazards (e.g., Zhao et al. 2015;. considered two main rehabilitation actions, relining and replacement, to enhance the resilience of WDNs to seismic hazards. ...
... However, the analysis was limited to 1 year, without considering the effect of deterioration and life-cycle cost on the rehabilitation planning decisions. Zhao et al. (2015) compared the effects of two strategies for enhancing the resilience of WDNs. They analyzed the impact of ductile retrofitting and meshed expansion on the seismic resilience of an actual WDN in China. ...
... Multiple measures can be plotted either separately [23], [108], [139], [149], [152] or together [28], [30], [106]. In some cases, balancing diverging performance measures is left as an open-ended trade-off. ...
... Productivity measures are relative to system demand, so constant targets imply system demand does not vary in time. Examples of constant performance targets for productivity measures include networking packet delivery ratio [113], supply delivered over a transportation network [52], potable water demand [152], electric demand [111], [175], and economic inoperability [150]. Some authors described their performance target as a function, allowing for time-varying normalization, but implemented a fixed value in their case study [37], [176]. ...
... To compare dissimilar curves, an analysis requires consistent control times. Some authors established 0 as the time of system disruption, [27], [62], [152]. This may be acceptable when all curves definitively begin with the same disruption, but it risks conflating hazard exposure with system disruption, undervaluing system attributes of resistance [75], detectability [184] and prediction [114]. ...
Resilience curves communicate system behavior and resilience properties to critical infrastructure stakeholders and can quantitatively facilitate resilient design. Generally, these curves illustrate the evolution of system performance before, during, and after a disruption. As simple as these curves may appear, the literature contains underexplored nuance when defining "performance" and distilling curves with summary metrics. This manuscript, through a review of 274 publications, defines a taxonomy of resilience curve performance measures and discusses associated performance targets and normalization techniques. Furthermore, a taxonomy of summary metrics is defined to facilitate comparisons of system behavior and resilience strategies. In addition to defining common taxonomies, this review synthesizes recommendations for selecting measures and metrics for common applications and stakeholders across critical infrastructure resilience domains. Key recommendations include broader adoption of productivity measures with variable and adaptive performance targets; deliberate consideration of curve milestones when defining summary metrics; and the need for future research on variable and adaptive weighting for ensemble measures and metrics.
... They utilized genetic algorithm and pressure-driven hydraulic simulation to select the optimal set of operational interventions such as resetting pressure-reducing valves and installing temporary bypasses to respond to several sudden failures. Other researchers, such as Zhao et al. (2015), focused on the restoration of WDNs after seismic hazards. Zhao et al. (2015) WDNs. ...
... Other researchers, such as Zhao et al. (2015), focused on the restoration of WDNs after seismic hazards. Zhao et al. (2015) WDNs. They analyzed the effects of ductile retrofitting strategy and meshed expansion strategy on the seismic resilience of an actual WDN in China. ...
Sustaining functionality of water distribution networks (WDNs) following hazardous events is essential to public health and safety. Developing efficient restoration plans for rapid recovery is needed because of several factors such as the ubiquitous nature of WDNs, severely deteriorated segments, increased level of urbanization, availability of various restoration methods, and possible uncertainties in time and cost estimates of such methods. This paper presents a multiobjective resilience-based optimization model that maximizes the resilience of WDNs while minimizing the total time and cost of the selected restoration plans. A real WDN was utilized to demonstrate the practicality of the proposed model. The problem was solved deterministically and stochastically to generate a prioritized list of segments to be restored along with a schedule of their restoration that accounts for available work crews. When compared with current planning practices, the output plan achieved 4% cost saving, 48% duration reduction, and 4% resilience improvement. The model is expected to help city managers establish optimal restoration plans, especially in cases of limited budget and workforce.
... Therefore, there has been a surge of interest in the water engineering community to deploy network analysis to assess the degree of resilience of water distribution networks. However, to the best of our knowledge, most of the existing proposals of resilience measures for water distribution networks are based on the network structure [11][12][13][14][15][16][17][18] or steady-state or quasi-steady-state flow rates [19][20][21][22][23][24]; as such, the dynamic, transient water flows in the pipe network cannot be represented, which is in fact the key to the resilience performance of a water distribution system. Furthermore, one needs to apply stresses to the system to measure resilience [18], which cannot exhaustively include all failures that might occur in a system. ...
Water distribution networks are hydraulic infrastructures that aim to meet water demands at their various nodes. Water flows through pipes in the network create nonlinear dynamics on networks. A desirable feature of water distribution networks is high resistance to failures and other shocks to the system. Such threats would at least transiently change the flow rate in various pipes, potentially undermining the functionality of the whole water distribution system. Here we carry out a linear stability analysis for a nonlinear dynamical system representing the flow rate through pipes that are interconnected through an arbitrary pipe network with reservoirs and consumer nodes. We show that the steady state is always locally stable and develop a method to calculate the eigenvalue that corresponds to the mode that decays the most slowly towards the equilibrium, which we use as an index for resilience of the system. We show that the proposed index is positively correlated with the recovery rate of the pipe network, which was derived from a realistic and industrially popular simulator. The present analytical framework is expected to be useful for deploying tools from nonlinear dynamics and network analysis in the design, resilience management and scenario testing of water distribution networks.
... where í µí°´í µí± is the annual resilience and í µí°¸isµí°¸is the mean operator. Zhao et al. [23] employed this timebased resilience measure to compare the technical and organizational effects of two post-disaster rebuilding strategies: pipeline ductile retrofitting and network meshed expansion. They concluded that retrofitting is a preferred strategy to enhance seismic resilience of WDNs under limited recovery budget and resources, whereas meshed expansion can increase the performance of WDNs in the case of sufficient fund availability. ...
... where AR is the annual resilience and E is the mean operator. Zhao et al. [23] employed this time-based resilience measure to compare the technical and organizational effects of two post-disaster rebuilding strategies: pipeline ductile retrofitting and network meshed expansion. They concluded that retrofitting is a preferred strategy to enhance seismic resilience of WDNs under limited recovery budget and resources, whereas meshed expansion can increase the performance of WDNs in the case of sufficient fund availability. ...
Water distribution networks (WDNs) face various types of hazards during their extended life. Ensuring proper functioning of WDNs has always been a major concern for utility managers because of their impact on public health and safety. Resilience is an emerging concept that aims at maintaining functionality of the WDNs. Most of the previously developed resilience frameworks employed simulation methods to assess resilience of the WDNs, focusing only on the specific aspects of resilience. There is a need to develop a holistic approach to evaluate the resilience of WDNs considering various dimensions of resilience. This paper presents a new multi-attribute resilience metric based on the robustness and redundancy of the WDNs, which can be used to achieve the purpose. The developed metric is used to evaluate the resilience of a WDN in the city of London, Ontario. An optimization framework for enhancing the current resilience level is also presented. Resilience of the network is found to increase around 20% with a $500,000 investment. A hazard scenario is then analyzed to illustrate the practicality of using this metric in selecting effective restoration strategies. The proposed metric can be utilized by water agencies to evaluate and enhance the resilience of WDNs, as well as to optimize the recovery process after disruptive events.
... (2) rapid identification of failure locations and service reduction; (3) effective isolation of failure sections [26,93,94]; (4) formulation of emergency strategies [73,83,95]; and (5) efficient allocation of recovery resources and repair of failed components [96]. ...
... WDNs are a class of engineering systems that must recover their function to the pre-disturbance equilibrium. Figure 3 visualizes the temporal progression of the absorptive, restorative, and adaptive capabilities in WDN resilience, as described in the references [96,103,104]. A WDN system with high absorptive capability could resist local failures and small disturbances during daily operation in the period T0-T1. ...
... Depending on their calculation process, simulation methods adopt either discrete [82,83,[124][125][126][127][128][129][130][131][132][133][134][135][136][137][138] or continuous [79,90,96,103,129] metrics. Both types of methods capture the evolving water demand and water quality in the system, but differ in when the information is relayed (at time points or during time periods). ...
Water distribution networks (WDNs) are critical contributors to the social welfare, economic growth, and public health in cities. Under the uncertainties that are introduced owing to climate change, urban development, aging components, and interdependent infrastructure, the WDN performance must be evaluated using continuously innovative methods and data acquisition. Quantitative resilience assessments provide useful information for WDN operators and planners, enabling support systems that can withstand disasters, recover quickly from outages, and adapt to uncertain environments. This study reviews contemporary approaches for quantifying the resilience of WDNs. 1508 journal articles published from 1950 to 2018 are identified under systematic review guidelines. 137 references that focus on the quantitative resilience methods of WDN are classified as surrogate measures, simulation methods, network theory approaches, and fault detection and isolation approaches. This study identifies the resilience capability of the WDNs and describes the related terms of absorptive, restorative, and adaptive capabilities. It also discusses the metrics, research progresses, and limitations associated with each method. Finally, this study indicates the challenges associated with the quantification of WDNs that should be overcome for achieving improved resilience assessments in the future.
