Shield tunnel segment structure and construction method thereof

Disclosed are a shield tunnel segment structure and a construction method thereof. The shield tunnel segment structure includes segment blocks sequentially spliced in a circumferential direction. Each segment block forms a closed annular segment structure, and outer diameters of adjacent annular segment structures gradually increase in an axial direction. At least two adjacent segment blocks of the same annular segment structure form an annular inner groove, and at least one segment block of the adjacent annular segment structures is provided with an inner bump which matches the annular inner groove. At least two adjacent segment blocks of the same annular segment structure form an annular outer groove, and at least one segment block of the adjacent annular segment structures is provided with an outer bump which matches the annular outer groove. The annular outer grooves and the annular inner grooves are staggered in the circumferential direction.