Evaluation of an automated bridge anti-icing system.

PDFTech ReportFHWA-NH-RD-13733G13733G, X-A000(153)Bridge decksAutomatic controlSprayersIce preventionBlack iceSnow and ice controlDeicing chemicalsEvaluationWinter maintenanceNew HampshireNew Hampshire. Dept. of TransportationBoisvert, Denis M.New Hampshire. Dept. of TransportationVermont. Agency of TransportationUnited States. Federal Highway AdministrationUS Transportation CollectionSome bridges and roadways are prone to moisture and icing conditions at times when there is no precipitation or when the rest of the highway system does not require treatment. These occurrences are difficult to predict. They delay the treatment of these surfaces and heighten driver exposure to unsafe conditions.This project involved the installation and evaluation of an automated anti-icing system intended to pre-emptively treat a bridge surface with de-icing chemical and eliminate the icing potential at the site. The three-year observation period and subsequent unofficial monitoring of the system operation has demonstrated that the system is effective in protecting the deck from icing.The system is used in conjunction with normal surface treatments during precipitation events as a cost savings measure. Following six years of service, the deck equipment was salvaged to allow for installation of a hot mix asphalt overlay and then re-installed. NHDOT intends to incorporate the system into the deck replacement project for this bridge, presently scheduled for 2018