1502207-A is referenced by 10 patents.
1502207 Tunnel linings J TSUZUKI 25 June 1976 [18 July 1975 5 April 1976] 26467/76 Heading E1F A concrete segment 1 for a tunnel lining consists of an arcuate concrete body member 2 having cavities in the joint surfaces of the body 2, each of the cavities being open from the inner surface of the body 2; metal joint pieces 3, 4 having bolt holes positioned in the cavities with the bolt holes exposed at the joint surfaces: and at least one steel frame member 5 embedded in the concrete body 2, the members 5 extending between the circumferential end surfaces of the segment 1 and being secured to the metal joint pieces 3. The segment 1 also includes longitudinal and transverse reinforcement 6, 32 respectively. The segment 1 is formed with a tongue 7 along one end and a groove 8 at the other end, and with a tongue along one side and a groove 10 along the other side.; The joint surfaces are also provided with a rebate adjacent the inner surface, the rebates forming grooves for sealing materials when the segments are assembled. In a first embodiment (Fig. 5) each end joint piece 3 includes an end plate 11 with bolt hole 15, side plates 13 and top plate 14. Each steel frame member 5 consists of pairs of bars 5 connected by vertical spacers (not shown), the frame members 5 being secured to the side plates 13 via connecting members 16. Anchor bars 33 are also secured to the side plates 13. The side joint pieces 4 (Fig. 8) are similar to joint pieces 3 and are held in place by anchor bars 19 embedded in the concrete. Fig. 15 shows how adjacent segments 1A, 1B are secured together by nuts 35 and bolts 34 passed through the bolt holes 15A, 15B, of adjacent joint pieces 3A, 3B.; In a second embodiment (Fig. 20) each steel frame member 43 consists of a pair of steel strips 47, 48 joined by spacers 49 and connected to the end joint piece 42 by connecting member 44. In a third embodiment (Fig. 41) each end joint piece 72 is connected to a steel frame member 74 (consisting of steel strips 79 joined by spacers 80) by reinforcing rods 81A and 82.