This nation has more than 11 million manholes which now need, or soon will need, to be rehabilitated. Current techniques are either too costly or do not last. This research speaks to this problem through development of an innovative technique of restoring many of these structures at less than half the cost of the reliable methods available today. The concept uses a newly developed applicator which can apply combinations of portland, high-alumina, or polymer cements. Fundamental to the requirement of a repair which lasts more than a few months is the application of sufficient thickness of a strong but inexpensive cement which can be protected with a coating of chemically resistant material such as latex or urethane. Key to the process is the ability of the applicator to place uniform thicknesses of cement of sufficient thickness without costly forms and without the need for people to enter the manhole. This not only reduces costs but improves safety. The potential commercial application as described by the awardee: The research will result in an innovative way to repair the nation's deteriorated sewage infrastructure.
