Stability of the Foundation of Buried Energy Pipeline in Permafrost Region

Abstract

During operation, a buried pipeline is threatened by a variety of geological hazards, particularly in permafrost regions, where freezing-thawing disasters have a significant influence on the integrity and safety of the buried pipelines. The topographical environmental conditions along the pipeline, as well as the influence of frost heave and thaw settlement on the pipeline’s foundation soil, must be considered in the design and construction stage. Theoretical analysis, numerical modeling, field testing, and mitigation measures on vital energy pipelines in permafrost have been widely documented, but no attempt has been made to review the freezing-thawing disasters, current research methodologies, and mitigation strategies. This article reviews the formation mechanisms and mitigation measures for frost hazards (e.g., differential frost heave, thaw settlement, slope instability, frost mounds, icing, river ice scouring, and pipeline floating) along buried pipelines in permafrost regions and summarizes and prospects the major progress in the research on mechanisms, analysis methods, model test, and field monitoring based on publications of studies of key energy pipelines in permafrost regions. This review will provide scholars with a basic understanding of the challenging freezing-thawing hazards encountered by energy pipelines in permafrost regions, as well as research on the stability and mitigation of pipeline foundation soils plagued by freezing-thawing hazards in permafrost regions under a warming climate and degrading permafrost environment.

Shrubification along Pipeline Corridors in Permafrost Regions

“…In addition, pipeline foundations (backfilled into pipe trenches) and periodical maintenance on flat or concave ground could also intercept or alter shallow groundwater paths, generate preferential flows in taliks, change the timing and routing of surface and groundwater runoffs, and create riparian habitats, which benefit the aquatic vegetation and shrub growth [55,59]. On slopes, disturbances from pipeline construction and the ensuing heating delay ground freezing in the ROW and may create preferential flow paths in the supra-permafrost subaerial talik under the ROW, because the ground has already re-frozen outside the ROW while inside the ROW, the ground maintains a perennially thawed cylinder (linear supra-permafrost subaerial talik) [60]. This, therefore, accelerates surface water or groundwater flows, resulting in enhanced water erosion on slopes and accumulating water and high nutrients at the slope toes and eventually on the valley bottoms, favoring the shrubification on the valley bottoms [44].…”

Monitoring the Permafrost Conditions along Pipeline Routes in Central Yakutia, Russia

“…With appropriate pipeline designs and mitigation measures, conditions tend to stabilize with time. Additionally, problems can be encountered during the operation phase as a result of the complex interaction between the pipeline and permafrost, which may include thaw settlement, frost heave, upheaval buckling, buoyancy, and slope instability [1][2][3][4][5][6][7][8][9][10]. Many of these issues can develop many years after construction in response to changes in the thermal regime of the right-of-way [11].…”