CT Scans of Asbestos Cement Pipes to Support the Development of Better Condition Assessments

The Dutch drinking water distribution network consists roughly of 25% (around 30,000 km) asbestos cement pipes. This pipe material has a relatively high priority to be renewed and therefore received quite some attention when it comes to the development of condition assessments that help water utility experts to prioritize which of these pipes to replace first. In the presented work, X-ray computed tomography (CT) was used to measure the degradation of the asbestos cement (AC) pipes taken out of the field. The CT scans provide a highly detailed view of the pipe degradation. The insight provided by these images poses several questions with respect to some of the core assumptions of the condition models currently in use. Moreover, the comparison of CT results to those of non-destructive, in-line inspection techniques will provide a new avenue for the validation of these techniques and their usefulness for the Dutch water utilities.