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  1. May 2017
    1. Frost Bulb
      Hugh M. French, a member of the department of geography at the University of Ottawa, states that “nowhere has the frost heave problem been more critical than in the recent design of proposed chilled buried gas pipelines in Arctic regions” in his article entitled “Periglacial Geomorphology in North America: Current Research and Future Trends.” These chilled buried gas pipelines must function under extremely harsh conditions. They will be exposed to sub-zero temperatures in Arctic regions. Any water and vapor will “migrate towards the pipe” causing a frost bulb to form. This frost bulb will lead to the formation of an ice lens or numerous ice lenses which will cause frost heave around the chilled buried pipe (French, 1987). There are currently many techniques to attempt to predict the behavior of a buried pipeline that experiences frost heave. One such attempt to describe this phenomenon was proposed by Selvadurai and Shinde, both members of the American Society of Civil Engineers, in which they describe a detailed model of a frost heave zone caused by its associate frost bulb. They base their model off of the “heave of a frost bulb zone that develops around the pipeline as it transmits its contents such as chilled natural gas” (Selvadurai & Shinde, 1993). 
      

      References

      French, H. M. (1987). Periglacial Geomorphology in North America: Current Research and Future Trends. Ecological Bulletins, 5-16. Selvadurai, A. P., & Shinde, S. (1993). Frost Heave Induced Mechanics of Buried Pipelines. American Society of Civil Engineers, 1929-1951.