Impact of pressure fluctuations on pipe failures in water distribution networks
File(s)
Author(s)
Rezaei, Hossein
Type
Thesis
Abstract
Water utilities operate ageing infrastructures that are degraded by environmental factors and operational stresses. Pipe failures have become a routine, resulting in major interruptions and extensive costs to the society.
Pipe failure is a result of complex interactions between a variety of factors contributing to the pipe’s structural degradation and ultimate failure. Previous studies have extensively reviewed environmental and pipe-related factors. However, long term impact of quasi-steady and unsteady pressure variations on metallic pipe failures is not fully investigated.
The overall aim of this project is to enhance the understanding of the dynamic pressure variations in water supply networks and evaluate their impact on pipe failures, with motivation to enhance the operational efficiency of water supply infrastructures by managing systems’ hydraulic conditions.
In this study, a large-scale survey sampling programme is designed and executed in order to gather network representative high frequency pressure samples. A metric is formulated to quantify the stresses imposed on pipes from pressure variations. Causal analysis is undertaken and relationship between pipe failure and predictor variables are investigated by developing logistic regression models. The study develops a methodology for investigating cost-effectiveness of intervention measures and economic justification of the calm networks.
The findings from the study illustrate positive associations between the system’s hydraulic variations and predicted probability of pipe failure. It is shown that deterioration models can be enhanced by including pressure variation characteristics as contributing factors to pipe degradation. Investment in achieving calm networks is demonstrated to be economically justifiable.
Pipe failure is a result of complex interactions between a variety of factors contributing to the pipe’s structural degradation and ultimate failure. Previous studies have extensively reviewed environmental and pipe-related factors. However, long term impact of quasi-steady and unsteady pressure variations on metallic pipe failures is not fully investigated.
The overall aim of this project is to enhance the understanding of the dynamic pressure variations in water supply networks and evaluate their impact on pipe failures, with motivation to enhance the operational efficiency of water supply infrastructures by managing systems’ hydraulic conditions.
In this study, a large-scale survey sampling programme is designed and executed in order to gather network representative high frequency pressure samples. A metric is formulated to quantify the stresses imposed on pipes from pressure variations. Causal analysis is undertaken and relationship between pipe failure and predictor variables are investigated by developing logistic regression models. The study develops a methodology for investigating cost-effectiveness of intervention measures and economic justification of the calm networks.
The findings from the study illustrate positive associations between the system’s hydraulic variations and predicted probability of pipe failure. It is shown that deterioration models can be enhanced by including pressure variation characteristics as contributing factors to pipe degradation. Investment in achieving calm networks is demonstrated to be economically justifiable.
Version
Open Access
Date Issued
2016-12
Date Awarded
2017-09
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Stoianov, Ivan
Graham, Nigel
Sponsor
Engineering and Physical Sciences Research Council
Severn Trent Plc
Grant Number
EP/G037094/1
Publisher Department
Civil and Environmental Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Engineering Doctorate (EngD)