Parameter sensitivity analyses of influence on thermal regime of embankment in Permafrost Regions along the Qinghai-Tibet Engineering Corridor

Several engineering projects have been built in the Qinghai-Tibet Plateau Engineering Corridor (QTPEC). The proposed Qinghai-Tibet Expressway will be located between the existing projects. The interaction of the thermal influence among the engineering projects will affect the stability of the permafrost and infrastructure. This study uses mathematical model and field observations, in conjunction with four factors along the QTPEC, to analyze the law of heat influence and the key impact factors of the permafrost embankment introducing the grey relational analysis. Results indicate that the extent of the embankment heat influence is negatively correlated with the embankment height and the mean annual air temperature (MAAT), while it is positively correlated with the pavement width and water content. After 50 years, the maximum and minimum distance of the heat influence from the foot of the embankment slope will be 32.45 m and 7.22 m, respectively. The most significant factor impacting the thermal regime is the MAAT. The pavement width is the second most significant, the water content is the third most significant, and the embankment height is least significant. The results are expected to serve as a guide for the design of the Qinghai-Tibet Expressway. •Multi-factors affected the thermal regime are considered.•The extent of heat influence of permafrost embankment is presented.•Field observations of the extent of heat influence of embankment are conducted.