Abstract:

Due to the train running in the long tunnels on highspeed railways in permafrost regions, the temperature in the tunnels increases, which will jeopardize the safe operation of the tunnels. In the paper, finite element analysis is made on the temperature field of the surrounding rock of tunnels in permafrost region on basis of the properties of the temperature field and by means of finite volume method and finite element method. Conclusions drawn are as follows: 1)For long tunnels on highspeed railways in permafrost regions, the highspeed running of the trains and the insufficiency of the ventilation system of the long tunnels cause heat accumulation in the tunnels, in turn cause the temperature in the tunnels to increase slowly in the future decades; 2)Although the temperature increase is insignificant, it causes great changes in the temperature field of the permafrost soil around the tunnels; 3)In this way, the thawing scope of the permafrost soil is enlarged, the thawing depth of the permafrost soil is increased, and the stability of the tunnel structures and the operation safety of the highspeed trains are jeopardized.

Key words: highspeed railway, long tunnel, permafrost, temperature field, thaw subsidence