The repair of a cast iron water main presents an opportunity to install a sacrificial anode,
which can reduce the rate of corrosion and thus potentially delay the occurrence of future
failures within the anode's zone of influence. While the additional cost of the anode is
small, is it a good economic investment? Using the spatial location of failures, cluster
analysis identifies zones of active corrosion defined as four or more failures, each no
more than 20m from its nearest neighbor within the cluster. Within these clusters, a
failure is considered to have occurred within a cathodically protected zone if the failure
occurred within 20 m. of a previously installed anode. Otherwise, the failure is
considered to have occurred within a zone that is not protected. Survival analysis shows
that the times to failure within cathodically protected zones are longer than the times to
failure in an unprotected zone. An economic analysis shows that the incremental costs of
sacrificial anodes indeed result in an economic benefit based on the deferral of future
failures and their associated costs alone. The subsequent delay in replacement of the main
represents a further economic benefit. Includes 6 references, tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 59 |
| Published : | 06/01/2007 |
