Study on New Treatment Technology of Subgrade Thaw Collapse and Deformation in Qinghai-Tibet Highway

Thaw collapse and deformation is one of the main subgrade diseases of Qinghai-Tibet highway. Its unceasing development will lead to the inhomogeneous deformation and will cause a huge influence on the driving safety and road life. Although the existing treatments have several types, it still has some certain limitations and the thaw collapse and deformation can’t be completely solved. This paper proposes a new solution, the cement gravel mixing trenchless combines with dry-laid rubble, to solve this problem through improving the compactness and capacity of subgrade, reducing the infiltration of precipitation and preventing the erosion of shoulder. Through the site implementation, this new method which can effectively solve the subgrade diseases caused by thaw collapse and deformation is verified.