Abstract:

According to the current situation of the coupled action of mechanical and thermal load occurring in the disposal engineering of nuclear wastes,the problem of additional stress fields for a circular lined tunnel considering the effect of the thermal response was investigated. By considering the stressdeformation characteristic of the total fields and applying the technique of series expansion, the appropriate stress functions were constructed and accordingly the complex potentials for every region were obtained. The sensitivity analyses for the hole stresses of the tunnel indicated that, compared with the unlined case, the existence of a soft liner can effectively weaken the hole stresses which will obtain a minimal value when the liner thickness reaches a  certain magnitude for a fixed liner rigidity. For a stiff liner, the stress concentration will take place when the liner thickness gets up to certain value for  fixed liner rigidity, and an  increment of the liner thickness is needed in order to decrease the hole stresses. To a certain extent, stresses resulting from  thermal expansion can counteract the hole stresses.

Key words: lined tunnel, additional stress fields, the theory of , complex potential, series expansion, thermal expansion