| 摘要 |
PURPOSE:To regulate dropping of concrete, by regulating the rotation speed of a cylindrical member which is rotatably connected to a tremie tube and has a spiral vane at its inside. CONSTITUTION:A concrete placing device 10 consists of a tremie tube 12, a cylindrical member 14 which is connected to the tremie tube 12 rotatably around the axis and has a spiral vane at its inside, and a rotating means 16 which rotates the cylindrical member. A disclosing device 50, formed with a plurality of rib members 52, is closed, concrete is placed in the tremie tube 12 and the cylindrical member, and the pouring speed of concrete is selected through control of the rotation speed of the cylindrical member 14. Further, the disclosing device 50 is opened to place concrete as concrete is prevented from making rapid contact with water. The disclosing device 50 is raised by a hydraulic jack 20 and simultaneously, the forward end of the cylindrical member is buried in the previously placed concrete to prevent the outflow and diffusion of cement. |
