Shield tunnel local segment replacement structure and construction method thereof

The invention relates to a shield tunnel local duct piece replacement structure and a construction method thereof. The shield tunnel local duct piece replacement structure comprises a supporting frame, a steel supporting plate, T-shaped fixing nails, new duct pieces and a fine aggregate concrete layer. The supporting frame is composed of a supporting ball, a rotating track, a plurality of fixing balls, a supporting rod and supporting legs. The steel supporting plate is cylindrical, and the length of the steel supporting plate is 2-3 times that of the segment. The construction method comprises the construction steps of determining material specifications, installing the steel supporting plates, installing and erecting the supporting frames, constructing the fine aggregate concrete layer, replacing pipe pieces and cleaning a site. The method has the advantages that the damaged segment is reinforced by adopting the fine aggregate concrete layer and replacing the new segment, and the effect is better than that of