THE MAIN ENGINEERING GEOLOGICAL PROBLEMS DURING RAILWAY CONSTRUCTION IN PERMAFROST OF QINGHAI-TIBET PLATEAU

Permafrost area is of special geological and geographic environment. It forms a unique engineering ge-ological condition. The paper-discuses the distribution of permafrost along Qinghai-Tibet Railway and ex-pounds the effect of frost heaving, thaw-settlement and harmful permafrost engineering geological phenomenon which caused by interaction between human activity and natural environment to railway construction.