AUTC project number: RR10.02 & 510020 (Supplemental)
Xiong Zhang (UAF)
Many roads in Alaska, such as the Dalton Highway, experience degradation during spring thaw due to the downslope running of shallow groundwater. The water flow down the slope and pools up in the road embankments, where it freezes, causing frost boils and subsequent road damage. One good example of this damage occurred at Beaver Slide, near mile 110.5 of the Dalton Highway. The frost boils have resulted in extremely unsafe driving conditions and frequent accidents. Past repair efforts indicate conventional road construction methods do not work. The Mirafi Nylon Wicking Fabric, developed by Tencate Geosynthetics (North America), offers a potential solution. Featuring high specific surface area and high permeability, preliminary laboratory tests of MNWF indicate that it has great promise as a cost-effective means to solve the frost boil 8 problems on northern road systems. This proposed project aims to verify the theory, testing MNWF at Beaver Slide using moisture and temperature sensors to gather measurements for one year. Upon evaluation, researchers expect improved performance of pavement at installation sites. Data will be gathered regarding soil properties at the site, observed thermal and moisture changes and pavement performance over a one-year period, analysis of frost boil mechanisms, and evaluation of MNWF effectiveness to mitigate frost boil problems. Research results may lead to incorporation of MNWF in the geotechnical engineering curriculum at UAF. Further, recommendations developed from the research will be useful in ensuring a reliable and economic design of roads in arctic environments. Additional funding extending project research.