Composite heat insulation lining structure of plateau frozen earth tunnel

The utility model discloses a composite heat insulation lining structure of a plateau frozen earth tunnel, comprising a preliminary supporting system for supporting a construction tunnel, an intermediate spacing layer which is arranged on the preliminary supporting system, and a second lining which is arranged on the intermediate spacing layer, wherein the preliminary supporting system, the intermediate spacing layer and the second lining are in full-ring structures for reinforcing and protecting the entire construction tunnel; the intermediate spacing layer comprises a composite waterproof plate which is arranged on the preliminary supporting system, a heat insulation preservation layer which is arranged on the composite waterproof plate, and a waterproof protection layer which is arranged on the heat insulation preservation layer; and the preliminary supporting system, the composite waterproof plate, the heat insulation preservation layer, the waterproof protection layer and the second lining are arranged from inside to outside and jointly form a composite lining structure. The composite heat insulation lining structure of the plateau frozen earth tunnel has simple structure, reasonable design, simple construction steps, convenience in construction and good use effect, can effectively reduce the heat exchange between the inside tunnel and the stratum, and plays the roles of protecting frozen earth, preventing water seepage of the tunnel, preventing frozen damage and the like.