Study on the height effect of highway embankments in permafrost regions

Thaw settlement is the main embankments distresses of highway in permafrost regions, according to survey data of the Qinghai–Tibet Highway (QTH). It can be effectively mitigated or even controlled by raising the embankment height. In view of this engineering problem, this study proposes the concept of the Height Effect of Embankment in Permafrost (HEEP). The concept represents the deformation and failure rules of embankment resulting from height variations. A thermal-elastic-plastic thaw settlement computational model is used to simulate the settlement processes of embankment, considering scenarios of different mean annual ground temperatures (MAGTs) and different heights. The model is validated by the field monitored data from a specific embankment section along the QTH. It is found that the total deformation of embankment is of considerable value and comes primarily from the thaw settlement of permafrost. Some special structures are recommended to supplement the built embankment, to ensure the stability of embankment in warm permafrost regions. The research results could provide essential theoretical and technological support for the transversal section design of highway embankments in permafrost regions.

► The thermal-elasto-plastic thaw settlement of embankment in permafrost regions was proposed.
► The conception of the Height Effect of Embankment in Permafrost regions (HEEP) is proposed.
► The settlement deformation is affected in a large scale of HEEP.
► The influence of HEEP on deformation becomes weaker with the rising of the mean annual ground temperature.
► Some other special structures should be adopted to ensure the stability of embankment in warm permafrost regions.