Demonstration and Inter-Comparison of Seasonal Weight Restriction Models – Phase II

Many miles of roads are in seasonal frost areas that are highly susceptible to damage during the spring thaw period. As freezing occurs from the surface downward, moisture is drawn toward the freezing front, ice lenses are formed, and the roadways become stronger. When the ice lenses (above still-frozen underlying layers) melt, the structure is left in an undrained, unconsolidated condition that is highly susceptible to damage under traffic. In seasonal frost areas, some state departments of transportation (DOTs) take advantage of the period of higher strength in mid-winter by using winter weight premiums (WWPs) to increase the allowable weight that trucks can haul. Conversely, to reduce damage during the spring thaw, many road management agencies apply spring load restrictions (SLRs). The objective of this effort was to provide an understanding of the reliability, benefits, costs, and risks of alternate approaches to scheduling seasonal load restrictions on roadways. The major tasks addressed in this Phase II report were to implement the models recommended from Phase I at demonstration sites and to calibrate those models, if required. The models included both degree-day threshold and frost-thaw depth prediction models. Output from the models was then compared with validation data provided by the DOTs involved in this study. These validation data consisted of subsurface temperature data (which were reduced by the research team to compute frost and thaw depths) and, in some cases, deflection and/or stiffness data from lightweight deflectometer (LWD) and falling weight deflectometer (FWD) tests. With the results of these implementation and validation efforts, recommendations based on accuracy, simplicity of use, and cost were developed to aid road management agencies in selecting which model or protocol is most appropriate for their intended purposes, personnel, and specific conditions.

• Record URL:
  http://publications.iowa.gov/35060/1/seasonal_weight_restriction_models_phase_II_w_cvr.pdf
• 
• Corporate Authors:

  Frost Associates

  3901 Teeside Drive
  New Port Richey, FL  United States  34655

  Iowa State University, Ames

  Aurora Program
  Ames, IA  United States 

  Iowa Department of Transportation

  Aurora Program
  800 Lincoln Way
  Ames, IA  United States  50010

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Miller, Heather J
  • Berg, Richard L
  • Kestler, Maureen A
• Publication Date: 2020-12

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Appendices; Figures; References; Tables;
• Pagination: 172p

Subject/Index Terms

• TRT Terms: Deflectometers; Freeze thaw durability; Frost; Load limits; Pavement maintenance; Predictive models; Seasonally frozen ground; Trucking
• Subject Areas: Highways; Maintenance and Preservation; Pavements;

Filing Info

• Accession Number: 01765570
• Record Type: Publication
• Report/Paper Numbers: Aurora Project 2014-01, InTrans Project 19-156
• Contract Numbers: Federal SPR Part II, CFDA 20.205
• Files: TRIS, ATRI, USDOT, STATEDOT
• Created Date: Feb 22 2021 10:21AM