Numerical Evaluation of Insulation Application to Embankment of Qinghai–Tibetan Highway

Abstract

In many cases, protecting permafrost from further thaw due to human activities might be the first choice for embankment design in permafrost regions. Two-dimensional finite-element analysis was conducted, in which phase change was taken into consideration to simulate the thermal regime of the Qinghai–Tibetan Highway with extruded polystyrenes. Based on the predicted maximum thaw depth in the following 50 years, a better position for insulation and the optimum thickness of insulation were presented and a reasonable width of insulation and the right construction season were suggested. The applicable range of insulation in embankment engineering of the Qinghai-Tibetan Highway in terms of mean annual air temperature was also suggested and the influence of geothermal field of permafrost on the applicable range of the insulation was discussed.