TREATMENT METHOD FOR SUPER-LARGE KARST CAVE CAVITY BEHIND TUNNEL WALL

Disclosed is a treatment method for a super-large karst cave cavity behind a tunnel wall. The treatment method comprises the following steps: cleaning loose debris in a predetermined area of a karst cave; performing reinforcing treatment on a karst cave cavity top plate in the predetermined area in a bolting-mesh shotcreting mode, and performing reinforcing treatment on karst cave cavity top plates outside the predetermined area in a concrete spraying mode; providing at a second predetermined distance on one side of a tunnel excavation contour a first support unit and a second support unit; filling concrete between first support columns to form a first guard wall, and filling concrete between second support columns to form a second guard wall; backfilling concrete between the first guard wall and the outer contour of the tunnel and between the second guard wall and the outer contour of the tunnel; performing waste debris backfilling on karst cave cavities on the side of the first guard wall and the second gua