JPH018621Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a manhole bottom block that constitutes the bottom plate of a manhole, and more specifically, it has a common structure that can be used for all manholes and can be mass-produced. This is related to the bottom block for manholes.

The manhole bottom block that constitutes the bottom plate of the manhole is usually
Manufactured for each manhole.

An example of a conventional manhole bottom block is shown in FIGS. 5 to 8. In FIGS. 5 and 6, 1 is a manhole body buried underground, 2 is a lid, and 3 is a bottom block constituting the bottom plate of the manhole body 1.
4 is an inflow pipe connected to the vicinity of the bottom of the manhole body, and 5 is an outflow pipe connected to the vicinity of the bottom of the manhole body.

As shown in FIGS. 7 and 8, the bottom block 3 has a cone-shaped upper surface 3a that slopes downward from the outer peripheral edge toward the center, and an inflow pipe 4 is provided on the upper surface. Inverts 3b and 3c (water guide grooves) connecting 4A and the outflow pipe 5 are formed.

Generally, the planar arrangement of the inflow pipe and outflow pipe in each manhole is different from each other.
The planar shape of the invert formed in the bottom block 3 is also different for each manhole, so conventionally, many types of bottom blocks with different planar shapes of the invert were manufactured in advance. Alternatively, a method has been implemented in which a bottom block with a flow path structure that matches the planar arrangement of the inflow pipe and outflow pipe at the manhole installation position is manufactured on-site. However, in the former method, in which multiple types of bottom blocks with different invert planar shapes are manufactured in advance, there is a problem in that the cost of the bottom blocks increases because it requires a large amount of money to manufacture and store the bottom blocks. On the other hand, in the latter method where the bottom block is manufactured on-site, a formwork for the bottom block must be made for each manhole and concrete is poured, so the manhole production cost is lower than in the former case. There were problems in that the height of the manhole was high, the time it took to install the manhole was long, and it was difficult to work inside the narrow manhole.

The purpose of this invention is to provide a manhole bottom block that has a common structure that can be used for all manholes, can be mass-produced, and can be manufactured at a lower cost than conventional ones.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of an embodiment of the manhole bottom block 6 according to the present invention, and FIG.
It is a sectional view taken along the - arrow in the figure. The manhole bottom block 6 of the present invention has an annular groove 6a inclined with respect to the horizontal plane.
A region 6b surrounded by the annular groove 6a is formed into a convex curved surface higher than the annular groove 6a. The outer peripheral wall 6c of the annular groove 6a has a notch 6d for attaching an inflow pipe and an outflow pipe.
and 6e are formed, and an inflow pipe and an outflow pipe are fitted into these notches 6d and 6e. The notches 6d and 6e are formed by placing a metal or wooden separator 7 in the formwork as shown in Fig. 3 in advance when forming the bottom block, and integrally forming the cutouts with concrete together with the outer peripheral wall 6c of the annular groove of the bottom block. The separator 7 can be formed in advance by removing the separator 7 from the outer peripheral wall 6c of the annular groove at the time of casting the product. (Incidentally, the bottom block 6 may be formed into concrete without the separator 7, and the notches 6d and 6e may be formed using concrete cutters when constructing the manhole.) In the bottom block of the present invention, different inverts are applied to each manhole. Since there is no need to form the bottom block, the bottom block having the same basic structure can be used for various manholes, and therefore the bottom block can be mass-produced.
Furthermore, since the bottom block of the present invention does not require the formation of an invert, it is possible to easily manufacture a manhole that requires a large number of inflow pipes.

Figure 4 shows the case where the bottom block 6 of the present invention is applied to a manhole having four inflow pipes 4, 4A, 4B, 4C and one outflow pipe 5, and the bottom block 6 of the present invention is applied to a manhole having four inflow pipes 4, 4A, 4B, 4C and one outflow pipe 5. The notch 6d and the notch 6e for the outflow pipe can be formed by removing a separator previously embedded in the outer peripheral wall 6c of the annular groove 6a during demolding.

Furthermore, by embedding a large number of segments having the same shape as the separator at predetermined intervals in most of the outer peripheral wall 6c of the annular groove 6a, the bottom can be applied to any manhole with any piping configuration. A block can be obtained, but if a concrete cutter is used, a bottom block with a structure in which a separator or the like is not embedded may be used.

As explained above, according to the present invention, it is not necessary to manufacture each manhole as in the case of conventional bottom blocks, and it can be mass-produced, and moreover, the manhole can be constructed in a shorter period of time than before. A bottom mass is provided. Therefore, according to the manhole bottom block of the present invention, a manhole can be constructed at a lower cost and in a shorter period of time than before, and the working conditions of workers can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the manhole bottom block according to the present invention, FIG. 2 is a sectional view taken along the - arrow in FIG. FIG. 4 is a plan view of another embodiment of the manhole bottom block of the present invention, FIG. 5 is a vertical cross-sectional view of a manhole with a conventional bottom block, and FIG. - arrow sectional view of the figure, Figures 7 and 8 are - and - in Figure 6.
FIG. 1... Manhole body, 2... Lid, 3... Bottom block, 3a... Top surface, 3b, 3c... Invert (water guide groove), 4, 4A, 4B, 4C... Inflow pipe, 5
... Outflow pipe, 6 ... Bottom block, 6a ... Annular groove, 6b
... Convex curved region, 6c ... Wall of the outer peripheral part (of the annular groove), 6d, 6e ... Notch, 7 ... Separator.

Claims (1)

[Scope of utility model registration request] A bottom block for a manhole, wherein an annular groove inclined with respect to a horizontal plane is formed along an outer peripheral edge, and a region surrounded by the annular groove is a convex curved surface higher than the annular groove, A bottom block for a manhole, in which a notch for attaching an inflow pipe and an outflow pipe can be formed in the outer peripheral wall of the groove.