Temporary grouting gallery and construction method thereof

The invention relates to the technical field of hydraulic and hydro-power engineering, in particular to a temporary grouting gallery and a construction method thereof. The temporary grouting gallery comprises a foundation surface and a replacement body. Replacement excavation space is arranged below the foundation surface of a dam and stretches to the geological flaw and influence zone of a riverbed portion, a grouting gallery body is reserved in the replacement excavation space, and the replacement body is poured into the replacement excavation space and outside the grouting gallery body. The temporary grouting gallery is arranged on the geological flaw portion and influence zone below the foundation surface, the contradiction between the construction period and geological flaw treatment is effectively avoided, and the linear construction period of a project is greatly shortened. The temporary grouting gallery of the structure is simple in structure and high in operability and reliability.