科研之友
微信
新浪微博
Facebook
分享链接
摘要
As an efficient and economical engineering measure, the inverted T-shaped crushed-rock interlayer is used to protect the permafrost under expressway. Its cooling performance is threatened by the climate warming, strong heat absorption of asphalt pavement and aeolian sand on the Qinghai-Tibet Plateau. However, the influence effect of the aeolian sand is unclear. In this study, a hydro-thermo coupled model, including ice-water phase change, heat and water transfer, and air convection heat transfer in the crushed rock, is established to simulate and evaluate the cooling performance of the inverted T-shaped crushed rock interlayer affected by aeolian sand clogging. A novel structure combining the L-shaped two-phase closed thermosyphons with the inverted T-shaped crushed-rock interlayer is proposed to satisfy the strict requirement of expressway. The numerical results show that the cooling effect of the inverted T-shaped crushed-rock interlayer on the underlying permafrost is influenced by aeolian sand to some extent, whose cooling effect is weak and concentrated at the embankment center. Permafrost beneath expressway was still degenerated, which is unfavorable for the long-term stability of expressway embankment. The novel structure can overcome the adverse effect of aeolian sand, produce a significant cooling performance on the permafrost under the embankment, and maintain the thermal stability of expressway embankment. Under the threat of aeolian sand, this novel structure is a candidate structure for the expressway embankment in permafrost regions.
-
单位中国科学院
