Test and Validation of a Model for Forecasting Frost on Bridges

Frost frequently forms on roads and bridges during winters when the pavement temperature is at or below 273 K and below the dew-point temperature. Accurate forecasts of frost onset times, frost intensity, and frost disappearance help roadway maintenance personnel decide when, where, and how much frost-suppression chemicals should be used. A finite-difference program has been developed that predicts bridge surface temperature by simulating vertical heat transfer in a bridge in response to evolving weather conditions. A vapor flux calculation uses the bridge surface temperature and concurrent meteorological variables from a weather forecast model to produce forecasts of depth of frost deposited, melted, or sublimed. Comparisons of model results with measured surface temperatures from a Roadway Weather Information System (RWIS) station have demonstrated that the model realistically represents early-morning low temperatures and temperature trends when run with input from current observations. Average surface temperature error using observations was 0.25 K. Some of the error can be attributed to spatial separation of the bridge site and the radiation observation site. BridgeT is capable of supplying surface temperatures within 1 K of measured values over a 40-hour forecast period if it is supplied with accurate weather forecasts.

• Record URL:
  http://www.lrrb.org/media/reports/200529.pdf
• 
• Corporate Authors:

  Iowa State University, Ames

  Department of Agronomy, 3010 Agronomy Hall
  Ames, IA  United States  50011

  Iowa Department of Transportation

  800 Lincoln Way
  Ames, IA  United States  50010

  Minnesota Department of Transportation

  Research Services Section, 395 John Ireland Boulevard, Mail Stop 330
  St Paul, MN  United States  55155
• Authors:
  • Takle, Eugene S
  • Greenfield, Tina
• Publication Date: 2005-5

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Figures; References; Tables;
• Pagination: 23p

Subject/Index Terms

• TRT Terms: Bridges; Finite differences; Forecasting; Frost; Mathematical models; Road weather information systems; Surface temperature; Weather forecasting; Winter maintenance
• Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation;

Filing Info

• Accession Number: 01597254
• Record Type: Publication
• Report/Paper Numbers: MN/RC-2005-29
• Contract Numbers: 82617 wo) 2
• Files: TRIS, ATRI, STATEDOT
• Created Date: Apr 25 2016 5:52PM