|
View Paper
HIGH-RESOLUTION MONITORING OF THAW SUBSIDENCE AFFECTING THE ACCESS ROAD TO UMIUJAQ AIRPORT IN NUNAVIK (QUEBEC)
Session: Infrastructure Performance in Cold Regions II / Performance des infrastructures en régions nordiques II
Richard Fortier, Centre d'études nordiques (Canada)
Shuai Guo, Centre d'études nordiques, Université Laval (Canada)
Pierrick Lamontagne-Hallé, Centre d'études nordiques, Université Laval (Canada)
Wenbing Yu, State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environment and Engineering Research Institute (Chine)
The thaw subsidence along a 300 m long segment of the access road to Umiujaq Airport in Nunavik (Quebec) has been annually monitored since 2006. This subsidence is due to thaw consolidation taking place in a layer of ice-rich silt underneath the road embankment. The increase in air temperature over the last two decades and the thermal insulation of snow cover on the embankment shoulders and toes explain the permafrost degradation. Thaw subsidence as much as 1.50 m has been recorded since the road completion in 1991. Rates of thaw subsidence from 0.056 to 0.138 m/year were observed. According to numerical modeling, the thawing rate is 0.317 m/year. The coefficient of consolidation varies between 1.63 and 3.14 m^2/year for corresponding thaw consolidation ratio from 0.937 to 0.675. The thaw consolidation of the silt layer is now completed and no more thaw subsidence is expected along the monitored road.
|
