Frost damage prevention drainage system for tunnel

The invention discloses a frost damage prevention drainage system for a tunnel. A heat-insulating buried water trench (6) is arranged below a primary support layer (1); multi-section draining pipes (7) are arranged in the heat-insulating buried water trench (6); an inspection shaft (8) is arranged between two adjacent draining pipes (7); the lower end of the inspection shaft (8) is communicated with the draining pipe (7); waterproof plates (11) are fully paved between the primary support layer (1) and a secondary lining concrete layer (2); annular punching bellows (12) and longitudinal punching bellows (13) are arranged on the outer sides of the waterproof plates (11); and openings at the lower ends of the annular punching bellows (12) are positioned in a gravel water seepage layer (10). According to the frost damage prevention drainage system disclosed by the invention, the phenomenon that the draining pipeline of a tunnel drainage system is blocked in severe cold regions due to freezing can be effectively prevented, the damage to a tunnel lining structure is avoided, the driving safety is ensured and the cleaning and maintaining expenses during operation are greatly reduced. The frost damage prevention drainage system has the characteristics of simple structure, easiness in implementation, favorable reliability, easiness in popularization and the like.