Maintenance Frequency Research Articles

A dynamic boundary condition finite difference model for predicting pavement profile temperatures: Development and validation

The appearance of ground frost is of vital importance in construction and maintenance of roads in cold climates. Frost often causes ground heave and subsequent road damage, which must be taken into account in designing the road structure. Frost depth, pavement temperature, and freezing/thawing cycles are also important for estimating the frequency of road maintenance and treatment. Various analytical, numerical, and empirical models have been developed to estimate the surface temperature of the pavement and to model the heat flow in the underlying layers. The pavement surface experiences a variety of intricate nonlinear heat transfer mechanisms during winter, making it challenging to accurately model the surface boundary. Dynamic variation of parameters such as cloud cover and traffic density during the modeling period introduces additional complexity. To address this challenge, we have established an experimental setup in Luleå, Sweden, to measure pavement profile temperatures during the winter season. Additionally, we have developed a Finite Difference Model that utilizes local weather data including dynamic cloud cover, and which also takes traffic into account. The experimental and simulation findings demonstrate how the impact of surface temperature fluctuations diminishes and, more or less, vanishes for depths more than 55 [cm] below the pavement surface. The Finite Difference Model presented in this study exhibits the ability to forecast the pavement profile temperatures, including the surface temperature based on weather conditions, with acceptable precision for at least 3 days. As a consequence, a reasonable assessment of pavement layer conditions appears feasible based on local weather conditions, and the model can serve as a useful tool for planning road maintenance and construction in cold regions.

Condition-based maintenance policy for shared service-oriented leased equipment

Due to growing consumer demands for immediacy, personalization, and high availability, equipment manufacturers are venturing into the sharing market with expanded shared leasing services. While selling usage rights of equipment, they provide additional services to the consumer in the role of equipment operators, such as free maintenance and swap. However, uncertain usage rates and return times in the shared model pose significant maintenance challenges. This paper proposes a personalized condition-based maintenance (CBM) policy accounting for these uncertainties and heterogeneous consumer usage patterns. By considering inspection, maintenance, and penalty costs, we minimize the long-run expected maintenance cost per unit of time for operators. In the numerical example, we compare our policy against fixed inspection interval CBM policy and non-fixed inspection interval CBM under average usage rate, demonstrating that personalized CBM reduces maintenance costs. Sensitivity analysis provides some managerial insights. Firstly, operators should adjust the number of free swaps strategically to manage the intensity of equipment swaps, and strike a balance between the increased maintenance costs due to the swap intensity enhancement and the improved user satisfaction and equipment availability resulting from the increased number of free swaps. Secondly, when the acceleration effect of imperfect maintenance on the degradation rate is strengthened, operators should prioritize reducing the frequency of imperfect maintenance and increasing the frequency of perfect preventive maintenance. Moreover, operators must make strategic investments in their maintenance actions, balancing maintenance costs and penalty costs to develop cost-effective imperfect maintenance improvement factors.

Research on Crude Oil Transportation Technology of Hu-Huan Pipeline in Huanqing Block

Abstract This study comprehensively analyzes the performance of the Hu-Huan-Huan Pipeline (Hu-Huan Pipeline) in the Huanqing Block under different crude oil transportation processes, especially the additive-modified transportation process and the blank oil transportation process. Through in-depth analysis of the properties of additive-modified crude oil, simulation tests, and hydraulic and thermal calculations, it aims to solve the transportation challenges of the Hu-Huan Pipeline under extreme environmental conditions and ensure the safety, efficiency, and economy of pipeline operations. Research results show that the additive-modified transportation process can significantly improve the fluidity of crude oil and enhance transportation capacity and safety. Adding an appropriate amount of additives can reduce the viscosity of crude oil, reduce internal friction in the pipeline, and improve fluid movement efficiency, thereby effectively reducing transmission pressure loss and increasing transportation stability. In contrast, although the blank oil delivery process is feasible under certain conditions, it has limitations under extreme conditions. The viscosity of blank oil is high and it is easy to form scaling on the inner walls of pipelines, which increases the frequency of pipeline cleaning and maintenance, and also increases operating costs and risks. By comparing and analyzing the performance of the two processes, the best transportation strategies and suggestions for Hu-ring pipelines are put forward. For the additive-modified transportation process, it is recommended to add additives appropriately and optimize transportation parameters to ensure stable transportation of crude oil and safe operation of the pipeline system. For the blank oil transportation process, it is recommended to clean and maintain the pipeline regularly to reduce the occurrence of scaling and blockage and improve the reliability and sustainability of the system. In summary, this study provides an important reference for the optimized operation of similar pipeline systems in the future. By fully considering the impact of crude oil performance and transportation technology, pipeline transportation efficiency can be effectively improved, operational risks can be reduced, and the safety and sustainability of energy transportation can be ensured.

Wheel-rail wear characteristics of a modern tram passing curves with small radius

The wheel-rail wear was predicted for modern trams with independently rotating wheelset running on a groove-shaped rail. The tram vehicle-track coupled dynamics model, considering the wheel-rail multi-point contact, was developed using software UM to evaluate the dynamic responses of the vehicle and track. Hertz contact theory, the FastSim algorithm, and Archard material wear model were used to solve the normal contact stress, tangential contact stress, and wheel-ail wear, respectively. The wheel and rail profiles were updated when the wear depth reached to 0.1 mm. In calculation, the wheel and rail wear was calculated and analyzed separately. The results of groove rail and independently rotating wheelset wear predicted by this model coincided with relevant literature, which proved the effectiveness of this model. The wheel and rail wear characteristics of modern trams passing through curved tracks with small radii and the influence of wheel-rail friction coefficient on wheel and rail wear were calculated and analyzed using this model. The results show that the wheel and rail wear on the circular curve and the rear transition curve is more intense. The wheel wear is the most intense on circular curve while the rail wear is on the rear transition curve. The wear of inner and outer rails and wheels of wheelset one increases with the increase of wheel-rail friction coefficient while the wear of inner and outer wheels of wheelset three have no obvious change. The wear of the inner and outer rails is the most intense at the gauge corner position while is the lightest at the guard rail. The wear of wheelset one is more intense than that of wheelset three and the inner wheel wear is more intense than that of the outer wheel. The present analysis contributes to improve the life of tram wheel and rail and reduce the frequency of wheel-rail maintenance during operation.

Ordinal Clustering Based Homogeneous Road Segments in Asphalt Pavement Maintenance and Rehabilitation Optimized Decision-Making

An increase in the number of work zones on roads and highways will result in more costs from the increased frequency of maintenance and rehabilitation (M&R) equipment transfers. The number of M&R decision-making segments can affect decision-making efficiency and the number of work zones. Fixed segmentation and traditional dynamic homogeneous segmentation techniques, such as the cumulative difference approach (CDA) and K-means algorithms, cannot determine the optimal number of decision-making segments. To address this issue, this paper proposes a method to develop a multi-year asphalt pavement M&R plan that incorporates homogeneous road segmentation based on an ordinal clustering approach (OCA). The proposed method first applies an ordinal clustering approach to the survey units to identify homogeneous segments. These segments are then incorporated into a multi-year asphalt pavement M&R optimization decision-making model to determine the M&R plan. Data from 2022 covering 15.9 km of continuous asphalt pavement on the Donglv Highway in Shanxi Province were selected for analysis. These results demonstrate: 1) the OCA exhibits superior decision-making accuracy compared with the CDA; 2) compared with the M&R plans for survey units and CDA for homogeneous segments, the proposed method's M&R plan can be resolved faster and see fewer work zones, all achieved with a similar level of investment and meeting performance improvement; and 3) the M&R plan generated using the proposed method requires lower M&R investment but achieves higher performance compared with the actual M&R plan. These findings validate the effectiveness of the proposed method in producing improved M&R plans.

Comparative life cycle assessment of three types of crumb rubber modified asphalt under different system boundaries

This study employs a life cycle assessment (LCA) to quantify the environmental impacts of three crumb rubber recycling technologies in asphalt rubber (AR) mixtures: wet, dry, and terminal blend. The analysis identifies key factors affecting their environmental performance across the life cycle. Results were characterized into climate change, stratospheric ozone depletion, fine particulate matter, terrestrial acidification, marine eutrophication, freshwater ecotoxicity, human toxicity, and Land use. Dynamic rankings of the three AR technologies along their life cycle stages in each impact category would enable identification of the influencing factors and provide reference for the further improvement. This study reveals that dry technology is likely to have the most significant environmental impacts across all categories (51.85 %-100 %), whereas terminal blended technology generally presents the lowest impact (51.85 %-88.89 %), with the exception of freshwater ecotoxicity (33.33 %) and human toxicity (22.22 %), where wet technology shows the least impact. The analysis underscores the importance of asphalt mixture designs, with appropriate binder content, potential reduction in surface course thickness, and reduced maintenance frequency, as strategies to enhance the environmental performance of AR technologies. The study concludes that the environmental performance of AR pavement is highly dependent on their in-service durability, with scenario-based analysis indicating that adequate durability ensures environmental effectiveness.

Performance enhancement of asphalt mixture through the addition of recycled polymer materials

Enhancing the performance of asphalt binders is essential for ensuring the long-term durability and serviceability of asphalt mixtures, as it can help reduce the frequency of maintenance and repair work, ultimately leading to the development of more sustainable transportation infrastructure. To achieve this goal, this study investigates the effects of incorporating recycled polymer materials, including reclaimed polyvinyl chloride (PVC) and polystyrene (PS) derived from household waste, into hot mix asphalt. The experimental work involved subjecting the polymer-modified asphalt binders to a range of physical tests, such as softening point, penetration, ductility, indirect tensile strength, Marshall stability, and moisture susceptibility, and the results showed that the addition of recycled polymers, with an optimal content of 4%, led to lower penetration values and higher softening point temperatures, indicating improved resistance to temperature changes. Further analysis of the asphalt mixture performance revealed several beneficial outcomes, including a decrease in flow, a boost in the asphalt mixture's resistance to moisture-induced damage, and an improvement in Marshall stability and indirect tensile strength, with the inclusion of 4% recycled polymers yielding increases in Marshall stability of 43.7% and 37.4% for PVC and PS-modified mixes, respectively, and increments in indirect tensile strength of 32.2% and 29.7% for the same mixes. The study concludes that the use of recycled polymers can effectively enhance the performance and durability of asphalt mixtures, contributing to the development of more sustainable asphalt pavement construction practices by utilizing locally available or reused materials, which could lead to the increased knowledge and application of stronger and more weather-resistant asphalt mixes, ultimately promoting the advancement of sustainable transportation infrastructure.

Pre- and Post-Improvement Performance of a Railway Embankment Stabilized with Ductile Inclusions

Large deflections and accumulation of permanent track geometry defects at railway soft spots cause significant operational issues including increased maintenance costs, decreased train speed, and, at an extreme, derailments and track failures. Reinforcing inclusions placed between the ties are a promising rehabilitation scheme to locally stabilize the embankment and transfer the loads to deeper, more suitable soils. In this paper we report the results of a long-term monitoring program to assess the performance of ductile inclusions, known commercially as “GeoSpike® elements”, to stabilize a rapidly deteriorating railway soft spot. Observations of track bed behavior are presented for 8 months prior to installation and 15 months after installation using a combination of LIDAR, Digital Image Correlation (DIC), and ShapeAccelArrays (SAA). Through the monitoring program, it was determined that the ductile inclusions decreased the average rate of deterioration by a factor of approximately 3, which allowed the frequency of site maintenance to be decreased from three times a year to once a year.

Mitigation of vibration and free-surface instabilities by using anti-vortex baffles in an industrial stirred vessel

Inadequate understanding of mixing dynamics can result in compromised product quality, increased production expenses and revenue loss. This study utilizes vibrometer measurements in both baffled and unbaffled eccentric flat-bottomed stirring vessels, containing a trisodium phosphate–water mixture, to investigate the impact of baffles on reducing vibrations. Through examining the effect of different configurations of baffles, this research effectively eliminates vortices and vibrations generated during agitation, consequently reducing maintenance frequency. Additionally, computational fluid dynamics (CFD) analysis is conducted on baffled and unbaffled stirred tanks, revealing streamlined patterns and mean velocities. By solving the Reynolds-averaged Navier–Stokes (RANS) equations with the k–[Formula: see text] turbulence model, obtained results reveal the importance of baffles in reducing vibrations and vortices while stabilizing the free-surface. However, balancing the number of baffles with impeller blades is crucial to prevent vibration regeneration.

Optimizing wind-solar hydrogen production through collaborative strategy with ALK/PEM multi-electrolyzer arrays

This paper presents an innovative sustainable hydrogen production system integrating solar and wind energy to provide power to alkaline (ALK) and proton exchange membrane (PEM) electrolyzers. On this basis, a novel source and load collaborative optimization strategy is proposed to optimize the hydrogen production system, aiming to address the challenges of the intermittent and variable nature of renewable energy sources. The proposed strategy consists of a classification prediction module using the XGBoost algorithm, which analyzes historical energy generation data to predict optimal electrolyzer operation. Furthermore, the proposed collaborative optimization strategy is able to balance the loads between the electrolyzer arrays, aiming to minimize cold-start situations, prolong steady-state hydrogen production time, and reduce operational variations due to maintenance. The proposed strategy is proved to significantly reduce the standard deviation of the electrolyzer runtime, enhancing the overall system stability, and contributing to the reduction of maintenance frequency. Theoretical analyzes and extensive simulation results validate the effectiveness of the proposed strategy in improving hydrogen production efficiency and sustainability. This work contributes to the integration of renewable energy sources for clean energy production, and provides a practical and effective solution for the urgently needed green hydrogen production.

Phase-type distribution models for performance evaluation of condition-based maintenance

ABSTRACT Condition-based maintenance (CBM) is gaining attention due to sensor and cloud-based analytics advancements, but research on its impact on system-level performance is limited. Insufficient understanding during CBM implementation can lead to confidence issues and failures. This study introduces a class of models using phase-type distribution to assess three maintenance strategises: run-to-failure (RTF), time-based preventive maintenance (TBM), and CBM. Employing machine health-index, the framework characterizes production performance by estimating effective process times. The model demonstrates how adjusting CBM thresholds influences process time variations and assesses the impact of changing maintenance frequency for TBM. Applied to a smart cellular manufacturing system, the model shows CBM’s early-stage implementation. Findings indicate CBM with optimized thresholds boosts maximum throughput by 6.77%. Further, CBM achieves an additional 6.84% increase assuming corrective maintenance time can be reduced by 20%. This approach can help manufacturing become smarter through smarter maintenance in the Industry 4.0 era and beyond.

Is it wise for manufacturers to implement preventive maintenance in the sharing business model?

In the sharing business model, manufacturers typically increase customer usage through product design but contend with escalating failure costs stemming from heightened customer usage and moral hazard concerns. The preventive maintenance (PM) typically serves as a means for manufacturers to tackle the growing failure cost problem. However, manufacturers face the challenge of how to make PM strategies in intricate operational environments. We formulate a theoretical model to investigate when a manufacturer should implement PM, taking into account customer usage and product design. Our results suggest that when the fixed cost of PM is low and the customer moral hazard is not sufficiently high, or when both the fixed cost of PM and the customer moral hazard are at moderate levels, it is wise for the manufacturer to implement PM. We also find that the PM can lead to higher consumer surplus by increasing customer utility, achieving a win-win situation. In addition, our findings reveal a positive correlation between the PM effort and product quality, with higher PM effort leading to higher product quality and thus increasing customer usage. In extension models, we further explore the issues of maximising social welfare, non-zero maintenance time and endogenous maintenance frequency

Impacts of seasonal activities and traffic conditions on the contamination and accumulation of gully pot sediments: Metal(loid)s and organic substances

Gully pots (GPs) are an integral urban drainage component, transferring surface runoff into piped systems and reducing sediment and contaminant load on downstream sewers and receiving waters. Sediment build-up in GPs impairs their hydraulic performance, necessitating maintenance for hydraulic function recovery. The variations in sediment accumulation rates between GPs suggested by earlier studies challenge the effectiveness of adopting a generalised maintenance frequency. This study addresses the knowledge gap regarding how various factors influence sediment contamination in GPs. The impacts of seasonal activities and traffic conditions on the contamination of sediments in 27 GPs in areas with varying traffic intensities and street features (roundabouts, intersections, and straight roads) were examined. Over one year, GPs were emptied twice, with sediments collected for winter-spring and summer-autumn accumulation periods. These sediments were analysed for 84 substances, including metal(loid)s, hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), alkylphenols, phthalates, per- and polyfluoroalkyl substances and organotins. Significant temporal changes were identified in key parameters such as electrical conductivity, total organic carbons, tungsten (W), heavy-molecular-weight PAHs (PAH-H) and diisodecyl phthalate (DIDP) in GP sediments, influenced by winter road safety measures and autumn leaf abscissions. Significantly higher concentrations of 4-tert-octylphenol, DIDP, diisononyl phthalate, antimony and W were identified in GP sediments from roundabouts compared to those at the other two street features, exclusively during the winter-spring period. This is attributed to the synergistic effect of winter road safety measures and stop-and-go traffic patterns at roundabouts. No consistent spatial and temporal patterns were identified for substance concentration and mass accumulation rates. Results underscore the potential to develop a prioritisation-based maintenance strategy as an opportunity to enhance the efficiency of GP maintenance operations, ensuring better resource allocation and reduced environmental impact.

Transcranial direct current stimulation enhances effort maintenance in ADHD

BackgroundYouth with attention-deficit/hyperactivity disorder (ADHD) exhibit increased effort aversion, likely due to deficits in anticipatory dopamine firing. Previous research has shown that transcranial direct current stimulation (tDCS) targeting the right prefrontal cortex can enhance activity in dopaminergic meso-striatal regions. However, the extent to which this specific tDCS configuration effectively modulates effort behavior in anticipation of rewards in ADHD remains uncertain. HypothesisWe expected an increase of effort maintenance and invigoration during and following our tDCS set-up compared to sham in subjects with ADHD. MethodsTwenty-four children and adolescents with ADHD (mean age: 11.6 years; 95 % CI [10.7, 12.4]) received 2 mA and sham tDCS for 20 min each. The anode was positioned over the ventromedial prefrontal cortex (PFC), while the cathode was placed over the right dorsolateral PFC, generating an electrical field with maximal strength in the right PFC. During and after the tDCS sessions, participants performed a button-pressing task aimed at earning delayed monetary rewards. Primary outcomes were effort maintenance (frequency of button presses) and invigoration (slopes of button presses), measuring motor task performance. ResultsWe observed a significant increase in effort maintenance both during (b = 2.66; p < 0.001) and after tDCS (b = 2.04; p= .007) compared to sham. No significant difference was found for invigoration during stimulation, while after bonferroni correction (p = 0.025) a non-significant decrease was found after tDCS compared to sham (b = −5.18; p = 0.041). ConclusiontDCS targeting the ventromedial PFC (anodal) and right dorsolateral PFC (cathodal) increases effort maintenance in children and adolescents with ADHD.

‘Stakeholder Perceptions’ of the Impacts of Climatic Features on Residents and Residences: A UK Study

Liveable housing environments face the menace of global climate change. Built infrastructure (including buildings and houses) continuously experiences significant impacts that are exacerbated by natural variability in the climate. Our study examined how climate change impacts the resilience of residential buildings, increases maintenance frequency, and the wellbeing and comfort of residents in UK residential buildings. This study used deductive reasoning and an empirical epistemological methodology as the basis of primary data collection via a questionnaire survey. The instrument was designed to gather data on the frequency of maintenance and the wellbeing of residents and their perceptions regarding the impacts of climate change. Through regression analysis of the data, the findings showed a significant relationship between climate change and the wellbeing of the occupants of UK residential buildings. Also, physical wellbeing and social wellbeing are more important to the occupants than their mental wellbeing. The cost of maintenance of residential buildings in the UK has an upward trajectory due to the continuously reducing resilience of building fabrics caused by the impacts of climate change; for instance, a recent increase in rainfall/storms resulted in unprecedented flooding, which damaged the fabrics of some UK residential buildings.

Planning Evaluation of Wastewater Treatment System of Jakarta Islamic Hospital Sukapura Kelapa Gading

This study aims to evaluate the effectiveness of the Wastewater Treatment Plant (WWTP) at the Jakarta Islamic Hospital Sukapura Kelapa Gading in meeting government regulations and effluent quality standards. Using evaluation and observation methods, primary and secondary data were collected to analyze the condition of the WWTP, including wastewater quality based on regulated parameters. The results showed that although the WWTP utilizes an anaerobic-aerobic biofilter system, there are still problems in maintenance and inadequate containment capacity. This resulted in the inability of the WWTP to meet quality standards for parameters such as Total Coliform and E.coli. Recommendations for improvement include increasing storage capacity, improving equipment, and increasing maintenance frequency.

Improving Maintenance Operations on Raw Material Conveying Equipment by Using TRIZ Technique

The objective of this research is to improve equipment used for conveying raw material in the construction material industry and establish standard procedures for maintenance by applying Theory of Inventive Problem Solving (TRIZ). Research methodology consists of 1) studying the maintenance system of raw material conveying equipment of the case study company 2) collecting data and prioritizing problems using a Pareto chart, 3) setting goals, 4) analyzing the causes of the problems with Why-Why analysis and 3 GEN techniques, 5) concluding the results. Results from the study in 2022 showed that problem occurred at sieves and vibrator base used for filtering raw materials resulting in a high maintenance frequency of 28 times. The causes of the problem are the improper shape of the sieves and the installation position of the sieve vibrator including the carelessness of the worker to turn off the vibrator. This research solved the problems by applying TRIZ as guidelines for designing new sieves and applying Total Productive Maintenance (TPM) in establishing standard procedures for maintenance. The results of the improvement during May-November 2023 showed that the frequency of sieves maintenance decreased to 3 times equivalent to 6 times per year approximately, achieving the goal of less than 14 times/year. The MTBF increased from the original 171.67 hours to 1,055.91 hours and the MTTR decreased from 3.04 hours to 2.55 hours. It can be concluded that TRIZ can be applied to improve the material conveying equipment by significantly reducing the maintenance frequency.

Three phase microcontroller based automatic change-over selection switch

The significance of electricity in a developed country cannot be underestimated because power instability problem affects the economy growth, productivity and infrastructure development. The issues of phase failure, losses and phase imbalance earth fault are main causes that lead to unstable and erratic power supply. Most homes and office complexes where single-phase supply is needed are supplied with three phases of power supply to allow change from one phase to another when there is fluctuation or complete outage of power supply on a particular phase. This operation is normally done manually and has caused a setback in terms of time wastage, strenuous operation, susceptibility to fire outbreak, electric shock and high maintenance frequency. When voltage supply on a phase is below 220V or above 415V, this system automatically disconnects the load from the phase and connects to another where the required condition is met. Therefore, this paper presents a Microcontroller Based Automatic Transfer Switching System which is made up of voltage sensing circuit, Hall Effect current sensor, relays, LEDs and LCD of PIC16F877A microcontroller. A system flow chart was developed, programmed with MikroC software and simulated using Proteus electrical software design. A 10KVA single phase generator was used as alternate power source. The load capacity of the design was determined by decoupling Maxwell’s Equations of 8KW and power loss using pointing vector equation as 0.25% of the peak load. The switch is tested to have function optimally within ±5% nominal voltage of 220 - 415V supply and produced approximately 20 seconds elapses during the entire process of power supply changeover. Hence this device is suitable for Industrial and Domestic use where 3-phase power supply is available with a stand-by power source.

Satisfaction with Maintenance of the Public Sector Employee Housing Schemes in Lagos State, Nigeria

The Public sector employee housing is a kind of housing arrangement, which accentuates the role of the employer (government as well as its agencies) in assisting to deliver housing, mainly for the public sector workers. However, not much is known of the occupants’ satisfaction with the maintenance features of housing provided through this scheme in a large metropolitan area such as Lagos State. This study investigated the Maintenance Satisfaction features in nine public-sector employee housing estates in Lagos state, Nigeria. A cross-sectional survey research design involving quantitative research approach was adopted. The survey was carried out between September, 2020 and March, 2021. Using stratified sampling technique, the estates were grouped into the local government area. Cluster sampling was used to select the local government area. Also, purposive sampling technique was used to select 688 housing units in the nine purposively selected housing estates. 500 copies of the administered questionnaire were correctly filled and returned by the participants and the information were subjected to descriptive statistics. Statistical package for Social Science(SPSS) was used to analyze the data. The results pointed out that the respondents were most satisfied with the promptness of response to security issues in the estate, frequency of collection and disposal of refuse, frequency of maintenance of power supply facilities and least satisfied with the frequency of maintenance of roads within the estate, frequency of maintenance of drainage facilities and frequency of fumigation of the estate environment. Therefore, to improve maintenance satisfaction of inhabitants in public sector employee housing schemes, the key stakeholders such as the architects, builders and so on should give priority attention to the key features that ensure residents’ satisfaction.

A metric for drinking water service reservoir performance as a sink or source of material

Abstract Service reservoirs (SRs) are a critical component of drinking water distribution systems that impact water quality. There are no performance measures to quantify or understand this impact. By applying the concept of sink or source behaviour to describe the processes of material accumulation and mobilisation within SRs, this research develops a practical metric to facilitate assessment and quantification of SR performance. It is demonstrated how a few weeks of continuous data from instrumentation deployment at both inlet and outlet of SRs is sufficient to reveal valuable insight into SR and network performance. Through real-world applications, we provide evidence that the metric was able to track SR performance showing both beneficial and detrimental impacts on water quality, as well as quantifying seasonality and the benefits of SR cleaning. Such insight is invaluable for proactive, justifiable, and targeted decisions on the location and frequency of maintenance and management interventions.