Analysing the Factors Contributing to Sewer Pipeline Failure under an Integrated Picture Fuzzy Environment with System Dynamic Modelling

This study addresses the critical challenge of sewer pipeline failures, a problem of significant environmental and economic consequence. Despite the widespread impact, a research gap exists in quantitatively understanding the factors contributing to these failures, hindering the development of targeted mitigation strategies. The study introduces a novel amalgamation of Picture Fuzzy Set Theory with the Delphi technique (PFDM) and the System Dynamic Modeling (SDM) technique to fill this gap. Findings from content analysis reveal four main factors and twenty-three sub-factors, with environmental and structural elements emerging as predominant contributors to sewer pipeline failures. The proposed PFDM identifies eleven sub-factors as primary culprits, highlighting the critical role of factors such as pipe age, materials, damages from third parties, internal corrosion, and various types of cracks and holes. Importantly, sensitivity analysis demonstrates the robustness of these findings, showcasing consistency across diverse expert opinions. The SDM technique further underscores the interconnectedness of influential factors, emphasizing the need for targeted interventions. This research offers valuable insights for environmental and drainage decision-makers, helping them prioritize interventions to reduce sewer system failures and their associated environmental impacts, such as sewer overflow and exfiltration. By focusing on the identified critical factors and their complex relationships, the overall resilience and longevity of sewer pipelines will be enhanced.