Quantitative evaluation method for sewer defects based on fuzzy comprehensive evaluation model
基于模糊综合评判模型的污水管道缺陷定量化评价方法

Based on fuzzy comprehensive evaluation model and analytical hierarchy process, a quantitative method to evaluate sewer defects is proposed by considering different defect types and their effects on the tightness, stability and functionality of sewers. Two case studies were conducted. Sewer Defect Index (H) of 1.09, with Ht of 0.44, Hs of 0.78 and Hf of 1.79, was obtained on a sewer in a city of Southern China, suggesting that the sewer was in the rank of emergent defect. In contrast, H of 0.24, with Ht of 0.34, Hs of 0.16 and Hf of 0.18, was obtained on an example case in ATV 149, suggesting that the sewer was in the rank of minor defect. Similar results were obtained by ATV evaluation method, which confirmed the reliability of our proposed method.