PREVENTION OF CRACKING IN CONCRETE OF CUT-OFF PLATE OF WATER PASSAGE TUBE

PURPOSE:To avoid the concentration of stress on concrete portion surrounding the outer edge of a cut-off plate by attaching a bar or tubular material to the cut-off plate outer edge provided on the periphery of a water passage tube surrounded by concrete. CONSTITUTION:A ring garter 11A is provided on the periphery of the tubular cylinder plate 10 of a flood-way tube 3, and a cut-off plate 7 is connected to the outer edge of the ring garter 11A. A tubular material 19 is attached to the periphery of the cut-off plate 7, whereby avoiding the concentration of overstress on concrete portion 20 near the outer edge of the cut-off plate 7. Also, a bar material having a cross section suitable to avoid stress concentration, e.g., bars of a round or oblong cross section, may be, besides said tubular material 19, attached to the periphery of the outer edge of the cut-off plate 7.