EFFECTS OF TEMPERATURE AND MOISTURE ON LOW-VOLUME ROADS. INTERIM REPORT

This report presents a thorough study on the effects of temperature and moisture on the load response of low-volume roads. The procedures developed herein can be used to formulate temperature and seasonal adjustment factors for low-volume roads and to estimate when and where seasonal load restrictions should be applied. Field studies were performed on two light pavement structures at the Texas Transportation Institute Research Annex. The tests consisted of taking pavement layer temperatures and Falling Weight Deflectometer deflection readings at hourly intervals throughout the day. In addition, six Farm-to-Market roads in different regions of the state of Texas were monitored monthly to evaluate temperature and moisture effects on pavement moduli. Falling Weight Deflectometer deflection readings, rainfall data, pavement temperature, and suction readings were collected over a twelve month period. The effects of rainfall on the moisture condition beneath a pavement were also examined. The deflection readings were then used to backcalculate the layer moduli of the pavements. It was found that the stiffness of low-volume roads increases with the increase of temperature and decrease of moisture. Another aspect of temperature effects on granular materials was examined from the point of view of stress relaxation. Laboratory testings in the form of relaxation tests at different temperatures were performed on a granular material in order to determine the time and temperature dependent properties of the material. The analytical models were developed based on a micromechanical approach. The granular base course materials were treated as elastic spheres in contact and subjected to temperature and moistuere changes. Comparisons between the backcalculated and the predicted pavement layer moduli were made to verify the models.

• Supplemental Notes:
  • Research study title: Investigation of the Effects of Raising Legal Load Limits to 80,000 lbs. on Farm-to-Market Roads.
• Corporate Authors:

  Texas Transportation Institute

  Texas A&M University System, 1600 E Lamar Boulevard
  Arlington, TX  United States  76011

  Texas State Department of Highways & Public Transportation

  Transportation Planning Division, P.O. Box 5051
  Austin, TX  United States  78763

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Chandra, D
  • Lytton, R L
  • Yang, W
• Publication Date: 1988-12

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 102 p.

Subject/Index Terms

• TRT Terms: Backcalculation; Base course (Pavements); Deflection; Field tests; Granular materials; Laboratory tests; Load limits; Low volume roads; Mathematical models; Moisture content; Pavements; Rainfall; Relaxation tests; Seasons; Soil suction; Stiffness; Temperature
• Uncontrolled Terms: Micromechanics; Models; Seasonal variations; Suction
• Old TRIS Terms: Pavement deflection
• Subject Areas: Data and Information Technology; Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces;

Filing Info

• Accession Number: 00486212
• Record Type: Publication
• Report/Paper Numbers: FHWA/TX-473-2, Res Rept 473-2, TTI: 2-18-87-473-2
• Contract Numbers: Study 2-18-87-473
• Files: TRIS, USDOT, STATEDOT
• Created Date: Aug 31 1990 12:00AM