Evaluation of spring load restrictions and winter weight premium duration prediction methods in cold regions according to field data

Abstract

Road pavements in frost-susceptible regions are challenged by frost-thaw induced damages. Spring load restriction (SLR) is intended to reduce road distresses caused by heavily loaded truck traffic. Winter weight premiums (WWP) is applied during early freezing season by increasing the maximum allowable axle loads to reduce the economic difficulties that trucking industries undergo during thaw season. While there are various timelines for applying and removing SLR, this paper reviews three of the SLR prediction models along with a WWP computer simulation and verifies the calculations based on each method using two years of monitored field moisture and temperature data from the fully instrumented integrated road research facility (IRRF) test road in Edmonton, Alberta, Canada. The results revealed that two of the methods showed a significantly better performance in determining the start and end dates of SLR as opposed to the other method. Computer simulations obtained the pavement critical depth beyond which traffic loading did not affect the subgrade material in early freezing season, and collected data aided in estimating the start date of WWP application on the test road. The results were in good agreement with the recommendations suggested by authorities.