Three Years’ Monitoring of IRRF Instrumented Test Road

The IRRF’s test road, nearly 500 m in length, is unique to Western Canada. Situated in Edmonton’s east end, the road consists of two test sections and a control section designed to investigate the use of Tire Derived Aggregate as embankment material and the performance of bottom ash and polystyrene board as insulation layers in cold climate conditions. During construction, the road was instrumented with more than 250 pavement and geotechnical sensors. The installed geotechnical instrumentation monitors compression behaviour, internal temperature, and drainage characteristics of the test sections, while the pavement instrumentation monitors the mechanistic responses of the pavement to traffic and environmental conditions. Data collected from these sensors is relayed in 15-s intervals to the IRRF’s laboratory facilities, where it is used to study pavement performance. Various activities are scheduled to study how seasonal changes affect the pavement. Falling weight deflectometer tests are conducted monthly on the test road to monitor seasonal changes in the pavement layers’ moduli, while the effects of temperature, moisture variations, and traffic loads on the different pavement layers are also evaluated. This paper summarizes the effect of seasonal variation on pavement responses as a result of 3 years’ monitoring of the control section, tire embankment and insulated sections of the IRRF instrumented test road. By analyzing several Falling weight deflectometer testing results and temperature data collected from different instrumented sections during the time of monitoring, this paper investigates the impact of freeze and thaw on subgrade soil resilient modulus and the benefits of using insulation layers to protect the subgrade soil.