Assessment of Pavement Response during Spring Thaw Using Heavy Vehicle Simulator Testing

Two indoor laboratory studies were performed at Laval University using a heavy vehicle simulator on two very different pavement structures. The flexible pavement structural response was tested in thawing conditions for different loading conditions. These tests were performed to document how the flexible pavement response changes with thaw depth and to validate the main findings and information available in the literature regarding pavement response during spring thaw and spring load restrictions policies. The results collected during the experiment are in accordance with some general findings identified in the literature. More specifically, signs of weakening appear as soon as the thaw front reaches the granular layer beneath the asphalt concrete, at a depth of about 250-300 mm, and peak response values of up to 200 % are observed either while the structure thaws or once thawing is almost completed in the subgrade soil.