Canadian Geotechnical Journal · 2012 · 99 citations · 22 references
Natural SciencesCivil EngineeringGeological EngineeringEngineering GeologyGeotechnical EngineeringSlope StabilityFrozen Ground ProcessesPeriglacial EnvironmentsPeriglacial ProcessesPermafrostPermafrost GeologyPermafrost ThawEmbankment StabilizationPermafrost Engineering GeologyPermafrost SoilsPermafrost StabilityPermafrost Thaw SettlementPermafrost-slope InteractionsSettlement Analysis Of EmbankmentsThaw Settlement
Permafrost-related engineering problems, especially thaw settlement, pose a major threat to railway stability on the Qinghai‑Tibetan Plateau. The study aimed to mitigate thaw settlement at section DK1139+780 by installing closed thermosyphons and a crushed rock revetment. Ground temperature and embankment deformation data collected since 2002 were used to assess the effectiveness of these remedial measures. The combined system lowered ground temperatures, raised the permafrost table, insulated the slope, cooled the underlying permafrost, reduced settlement, and thereby enhanced railway stability.
Due to the special engineering geology characteristics of permafrost, construction in permafrost regions tends to result in serious permafrost-related engineering problems. Thaw settlement induced by permafrost degradation is the principal challenge for railway construction on the Qinghai-Tibetan Plateau. It threatens the stability and safety of the railway system, especially in warm and ice-rich permafrost regions. Thaw settlement in section DK1139+780 along the Qinghai-Tibetan railway is a potential risk to the safety of the railway, and a combination of closed thermosyphons and crushed rock revetment was used to remedy permafrost warming and thaw settlement of the embankment. Based on ground temperatures and embankment deformations observed at this site since 2002, the effects of the remedial measures were evaluated. The results show that the remedial measures lowered the ground temperature and raised the permafrost table. The crushed rock slope protection acted as an insulation layer and reduced heat flux into the embankment. The thermosyphons lowered the permafrost temperature and had a good cooling effect on the underlying permafrost. The results show that the remedial measures using two-phase thermosyphons and crushed rock revetment decreased the settlement of the embankment and improved the stability of the railway system.
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Subsidence risk from thawing permafrost
Frederick E. Nelson, O. A. Anisimov, N. I. Shiklomanov · Nature · 2001 · 466 citations