| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for preventing floatation of a built-up manhole, which is practically applicable to and advantageous for prevention of floatation of an existing manhole, without having to excavate the circumference and which is easy to construct, and to provide a manhole to which the method is applied. SOLUTION: Segment-like weight bodies 13a-13d, having bottoms molded according to the shapes of an invert 11 provided at the bottom of a skeleton 9 of the built-up manhole and an outflow pipe 12 provided on a vertical wall 10 of the skeleton 9, are disposed annularly along the shape of the inner wall surface of the vertical wall 10; each of the weight bodies 13a-13d is connected by a connecting fitting 15; and apparent specific gravity of the built-up manhole as a whole is set to 1.0 or larger. COPYRIGHT: (C)2010,JPO&INPIT |
