青藏公路多年冻土路基病害

根据青藏公路30年观测调查资料，分析不同时间段多年冻土地区公路路基病害的主要类型与特征。通过典型路段路基病害揭示，在全球气候趋暖的环境背景下，路基下多年冻土升温，冻土上限下降，冻土退化融化，由此导致的路基病害仍在发生、发展，路基病害以融沉为主，路基变形极不均匀。长期实践证明，传统的靠提高路堤保护冻土来保证路基稳定的方法有很大的局限性，应探索主动冷却路基的防治措施。

Subgrade Failure of Qinghai～Tebit Highway in Permafrost Area

On the basis of the observed data for 30 years and the analysis of subgrade failure in different period, the main type and characteristic of highway subgrade failure in the permafrost area are demonstrated. The typical subgrade failure of road section shows that with the global temperature becoming higher, the temperature of the frozen earth beneath subgrade is risen while it's top limit are descended and resulted in worse and thawing. So the subgrade failure is gonging on. Thaw collapse is one of important problem, it makes the deformation of subgrade variously. The long practice told us using the common measures to heighten the embankment is not good enough for the protection of the road subgrade stabilization. New effective measures are developed such as an initiative cooling measure.