| 摘要 |
PROBLEM TO BE SOLVED: To improve workability and safety of a Melan erection part in the case of erecting an arch rib for a concrete arch bridge by a Melan construction method. SOLUTION: A pair of overhang erection parts are closed with a Melan material 14 and then lined with concrete to construct a Melan erection part 16. The lining is performed in the state of arranging a pair of main trusses 24 constituting both side parts of the Melan material 14, to be exposed to the inner side faces 18a of a pair of webs 18 constituting both side parts of the Melan erection part 16. Each main truss 24 is thereby used as an inner form for placing concrete to dispense with the inner form. Consequently, there is no need to remove a frame 26 for connecting both main trusses 24, prior to placing concrete to avoid interference with the inner form. As a result, workability of the Melan erection part 16 is improved, and a lowering of torsional rigidity of the Melan material 14 is prevented to enhance safety in construction. Further, the frame 26 is left after the completion of erection to enhance the torsional rigidity of the Melan erection part 16. |
