The Solutions and Practical Results for Permafrost Engineering Problems of Qinghai -Tibet Railway

The Qinghai-Tibet Railway (QTR) is the highest-elevation one for passenger trains in the world and the first railway to connect central China with Tibet.It has kept operating very well for nearly 10 years so far.In this paper, the major solutions to geotechnical problems of permafrost for the construction and their effects are investigated, which are active methods of crushed roadbeds, heat pipe roadbed and dry bridges for construction.The major engineering problems, railway embankment cracks and deformation after operation and their solutions are given, which are active protections of more slice stones along embankment slopes, extra heat pipes along sunny embankment slope and reclaimed soil to keep from water.The observations from the long-term monitoring system have shown that the engineering protections of the Qinghai-Tibet Railway are completely successful no matter what design, construction, and operation.