Plastic Pipes Conference Association # 2021 Amsterdam
Karel van Laarhoven, Andreas Moerman
Pipe failure in drinking water distribution networks occurs as a result of loadings on the pipe that exceeds its strength. Especially, pipes that deteriorate over time have an increasing probability of failure. Prediction models that estimate when a particular pipe will fail can therefore be valuable tools in pipe replacement strategies. In order to create such a tool, traditional models for plastic failure and slow crack growth in PVC-U were embedded in an existing computational tool for stresses in mains. Condition assessments of excavated pipes were used to collect the material parameter values needed for the resulting model and a sensitivity analysis of the model was performed. The condition assessments show large variations in material properties. The sensitivity analysis of the model shows that data with a very high level of accuracy will be needed for a priori lifetime predictions. By exploring the combined failure-, degradation- and loading mechanisms in a single model, insight into their interaction and into the contribution of each to the total process is acquired. With that, the tool provides a starting point for utilities to prioritize their efforts concerning exit assessments and inspection, with the ultimate aim of better time of failure predictions for individual pipes.
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