TUNNEL INVERT STRUCTURE AND METHOD FOR MANUFACTURING INVERT

PROBLEM TO BE SOLVED: To provide a tunnel invert structure which allows a product handling weight to be reduced, prevents cracking or chipping during handling, and corresponds to a tunnel curve; and a method for manufacturing an invert.SOLUTION: A framework structure 25 is assembled from an embedded partition plate 29 having a contour including a circular arc 37 of the inner circumference of a tunnel and a chord 39 which connects both ends of the circular arc 37 and has a concave cutout part, a connection plate 31 which connects at least two embedded partition plates 29 facing each other spaced at a predetermined distance in the axial direction of the tunnel, a bottom plate 33 which bridges each of the bottom side parts of the concave cutout parts of two neighboring embedded partition plates 29, and a side wall plate 35 which comes in contact with each of the side parts of the concave cutout parts of two neighboring embedded partition plates 29. A plurality of the framework structures 25 arranged in the axial direction of the tunnel are embedded in a concrete 27 dammed with the bottom plate 33 and the side wall plate 35 preventing placement into the concave cutout parts, so that the framework structure 25 and the concrete 25 are integrated with the bottom 15 of the tunnel.