Large-Strain Nonlinear Thaw Consolidation Analysis of the Inuvik Warm-Oil Experimental Pipeline Buried in Permafrost

Abstract

The large strain nonlinear thaw consolidation model developed by Dumais and Konrad is used to analyze the Inuvik experimental warm-oil pipeline built on ice-rich permafrost foundations. The predictions for the thaw penetration rate, the final thaw settlements, the settlement rate, and the maximum excess pore water pressure compare favorably with the field observations. The modeling results are compared with the results obtained by the small strain linear thaw consolidation theory formulated by Morgenstern and Nixon. The Dumais and Konrad model offers a notable increase in precision given the large strain configuration used for the definition of the thaw penetration rate and the nonlinear characterization of the e−σv′ and e−kvT relationships. The Dumais and Konrad model improves on the formulation of one-dimensional thaw consolidation theory to yield a lifelike assessment of thaw consolidation by the introduction of a second moving boundary at the surface and by considering the changes of soil properties as thaw consolidation proceeds. An important practical implication of the model is the ability to handle a complex initial frozen soil profile and its corresponding soil properties.