Method for reducing frost heave of refrigerated gas pipelines

Abstract From the Canadian patent

In order to prevent damage due to frost heaving of a refrigerated gas pipeline which traverses frost-susceptible soil resulting from horizontal ice lense formation beneath the pipeline heat pipes are located in diame-, trically opposed pairs one on either side of the pipeline. Frost bulbs are formed in the soil around each heat pipe adjacent to the pipeline causing the horizontal ice lenses to be formed further below the pipeline. Heaving rate is reduced due to the lower temperature gradient in the vertical direction, a greater overburden above the horizontal ice lenses and a reduced water supply directly beneath the pipeline. Also lateral expansion, of the frost bulbs provides opposing …