A method of manufacturing a tunnel (10) or shaft lining or pipeline of segments (12), wherein each segment (12) comprises a concrete body (11) having an extrados (13) surface, an intrados (14) surface and first and second ends (15, 16) and first and second sides (17, 18), the ends (15, 16) and sides (17, 18) providing edge portions, the segments (12) being adapted to be connected to further similar segments (12) with edge portions adjacent edge portions of adjacent segments (12), the method being characterised in that the method includes enveloping the ends (15, 16) or sides (17, 18) of at least a pair of segments (12) in a reinforcing material as the concrete is cast, and once the concrete has cured, connecting the segments (12) together with one of each of their enveloped ends (15, 16) or sides (17, 18) adjacent, and sealing between the enveloped ends or sides.