Amidst global scarcity, preventing pipeline failures in water distribution systems is crucial for maintaining a clean supply while conserving water resources. Numerous studies have modelled water pipeline deterioration; however, existing literature does not correctly understand the failure time prediction for individual water pipelines. Existing time-to-failure prediction models rely on available data, failing to provide insight into factors affecting a pipeline's remaining age until a break or leak occurs. The study systematically reviews factors influencing time-to-failure, prioritizes them using a magnitude-based fuzzy analytical hierarchy process, and compares results with expert opinion using an in-person Delphi survey. The final pipe-related prioritized failure factors include pipe geometry, material type, operating pressure, pipe age, failure history, pipeline installation, internal pressure, earth and traffic loads. The prioritized environment-related factors include soil properties, water quality, extreme weather events, temperature, and precipitation. Overall, this prioritization can assist practitioners and researchers in selecting features for time-based deterioration modelling. Effective time-to-failure deterioration modelling of water pipelines can create a more sustainable water infrastructure management protocol, enhancing decision-making for repair and rehabilitation. Such a system can significantly reduce non-revenue water and mitigate the socio-environmental impacts of pipeline ageing and damage.

In recent years, the escalating frequency and intensity of extreme weather events like cold waves have heightened concerns regarding their impact on buried water pipelines, posing notable challenges to urban safety. These pipelines are particularly vulnerable to damage from the extreme low temperatures induced by cold waves, which can lead to significant system failures. This paper investigates the mechanical response of buried water pipelines to traffic loading before and after a cold wave using the Finite Element Method (FEM). Initially, a 3D numerical model was created to simulate the temperature distribution in the soil and buried pipe, utilizing field monitoring data gathered during a cold wave event at Shanghai city of Eastern China. Subsequently, a mechanical analysis of the soil-pipe model was conducted, employing the validated soil and pipe temperature field as predefined fields. The effects of temperature change rate, traffic load type, load position, and burial depth on the pipeline behavior are discussed in detail. The results demonstrated that cold waves significantly impact pipeline stress, an effect that is intensified by increased traffic loads. The peak Mises stress increased by up to 21 % for the 1.0 MPa load, underscoring the role of cold waves in amplifying pipeline stress. Moreover, while cold waves increase pipeline stress and vertical displacement, accelerating the rate of temperature change induced by the cold wave reduces the stress. Traffic load exerts the most significant impact at the bell and spigot joints, with effects remaining consistent regardless of joint position. Shallow-buried pipelines experience more pronounced stress changes in the presence of cold waves and traffic load, with stress increasing by 66.8 % at a depth of 1.5 m. This study demonstrates that the bell and spigot joints of shallow-buried pipes are highly susceptible to cold wave effects, especially under traffic loading, necessitating special attention to this potential failure location during such conditions.

Large landslide instability will throw rock and soil into the water, causing massive surge waves, damaging the underwater pipeline structure, and endangering the lives and property of coastal residents. This study uses the RNG kappa-epsilon turbulence model and the VOF method to numerically simulate the landslide surge based on the physical experiment model. This paper simulated the characteristics of the surge generated by the sliding block entering the water, analyzed the time history changes of the free surface, the factors influencing the surge height, and the flow field characteristics around the pipeline. According to the simulation results, the maximum surge height has a nonlinear increasing law with entry velocity, entry angle, and slider volume and a nonlinear decreasing law with water depth. At the back of the pipeline, the first collision between the forward-advancing surge and the reflected reflux surge will create a collision zone. Until the water surface is stagnant and gone, the collision zone will travel forward due to the rise in reflux water velocity and backwards due to the secondary wave produced by the surge. The simulation results corroborate the findings of physical experiments, which can provide technical assistance in protecting underwater pipelines, ensuring people's livelihoods, and maintaining urban public safety.