Pre-evaluation on stability of proposed expressway embankment with existing geothermal regulation measures in permafrost regions

Embankment stability is the primary problem for the expressway construction in permafrost regions. The proposed Qinghai-Tibet Expressway (QTE) is planned to construct along the Qinghai-Tibet Project Corridor. Confronted with harsh environmental condition and intense heat exchange between earth and atmosphere, it is necessary to predict and evaluate the stability of the proposed QTE. In this study, the factors affecting the embankment stability are analyzed firstly. And then, a scheme for the stability evaluation of the embankment is established. Finally, the evaluation scheme is used for the pre-evaluation of the stability for the proposed QTE with different geothermal regulation measures (GRMs). The results indicate that the influencing factors include climatic environment, permafrost property, engineering condition and geological condition, and among them, engineering condition and permafrost property are the main influence factors for embankment stability. The stability of the proposed QTE varies greatly in the different geomorphological regions. The application effect and contribution to embankment stability of the existing GRMs are different, and using GRMs cannot completely overcome the influence of various factors on expressway stability. In the construction process, different GRMs should be adopted depending on the geomorphological environment where the embankment is located to ensure the embankment stability.