JPH028090B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a buried object for forming a waterway such as a water supply and sewage pipe, a sewage channel, or a drainage channel.

A buried object for forming a waterway is installed in an excavated trench while filling it with a stabilizing liquid, and is then supported by the ground by solidifying the stabilizing liquid. The stabilizing liquid is solidified by adding a fixing agent to it and stirring it, and a large number of bubbles are generated during stirring.

(Prior Art) Conventionally, a buried object for forming a waterway has been defined only by having a flat outer surface at its bottom. For this reason, bubbles generated during stirring of the stabilizing liquid and the solidifying agent stagnate on the outer surface of the bottom of the buried object, resulting in voids in the solidified layer of the stabilizing liquid after solidification.

Due to the existence of such voids, the supporting force of the buried object may become insufficient and the buried object may sink. In addition, this subsidence destroys the connections between buried objects, causing water leakage in the case of drainage channels.

(Objective of the Invention) Therefore, the present invention provides a method for preventing air bubbles generated when the stable liquid is stirred together with a solidifying agent added to the stable liquid in order to solidify the stable liquid to stagnate under the bottom of a buried object for forming a channel. The purpose is to prevent this from happening.

(Structure of the Invention) The buried object for forming a waterway according to the present invention is characterized in that it has a bottom that is convex downward, and that the bottom has an outer surface that includes one or more inclined surfaces or curved surfaces.

(Operations and Effects of the Invention) According to the present invention, a large number of bubbles generated when the stabilizing liquid in the slot into which the solidifying agent has been introduced is stirred.
It rises along the sloped or curved surface that defines the bottom outer surface of the buried structure for forming a waterway. This prevents air bubbles from stagnating on the outer surface of the bottom, so that no voids are created in the solidified layer of the stabilizing liquid. As a result, sufficient ground bearing capacity to support the buried object can be ensured.

(Embodiments) The features of the present invention will become clearer from the following description of the illustrated embodiments.

Referring to FIG. 1, a pipe 10 consisting of an upper piece 12 made of concrete and a lower piece 14 which is a buried object for forming a waterway according to the present invention is connected to each other.

As shown in FIG. 2, the upper piece 12 and the lower piece 14 are each formed into a plate shape and a U-shape when viewed in cross section. The upper piece 12 placed on the open upper end of the lower piece 14 has a nut 15 screwed onto its upper end, a lower end that extends downward through the upper piece 12, and is embedded in both sides 14a of the lower piece 14. It is fixed to the lower piece 14 via a bolt 18 that is screwed into the insert 16. Further, the upper piece 12 can be approximately twice as long as the lower piece 14 in the axial direction. However, the length of the upper piece 12 in the axial direction is not limited as described above, and any length can be selected. Upper piece 12 and lower piece 1
4, that is, the lower surface of the upper piece 12 and the upper end surface of both sides 14a of the lower piece 14, are provided with a recess 20 and a protrusion 22, respectively, which extend in the axial direction of the tube 10 and can engage with each other. It is being

The lower piece 14 has a bottom portion 14 that is convex downward.
b, and the bottom part has an outer surface consisting of a pair of sloped surfaces 23 and a flat surface 25 located between and continuous with the sloped surfaces. The length of the flat surface 25 is significantly shorter than that of the inclined surface 23 when the lower piece 14 is viewed in cross section.

In addition, as shown in FIG. 3, the lower piece 14
has joint fittings 24 made of channel steel embedded in each end of both side parts 14a with a part protruding in the axial direction of the pipe 10, and the pair of lower pieces 14 are connected to the joint fittings 24 facing each other. Connected by engagement. A joint groove 26 that is formed when the pair of lower pieces 14 are connected to each other is provided on the inner surface of both side portions 14a of the lower piece.

The method of burying the pipe will be explained with reference to Figure 4.
First, in front of the lower piece 11 that has already been installed to connect the pipes to form a conduit (to the right in the figure)
Next, a groove hole 30 is excavated with an excavator such as a bucket hoe or a clamshell (only a bucket of clamshell is shown as an example) while filling with a stabilizing liquid 28 such as muddy water.

When excavating the trench hole 30, in order to prevent the existing lower piece 11 from being damaged by the excavator and to prevent excavated soil from flowing into the existing lower piece 11, It is preferable that a locking box 32 having a large wall thickness and a side portion that can be engaged with the joint fitting 24 is suspended and engaged with an end of the existing lower piece 11. Furthermore, in order to reduce the consumption of the stabilizer 28 as much as possible and prevent its waste, it is desirable to arrange a partition gate 31 inside the existing lower piece 11.

Next, after removing the locking box 32,
As shown in FIGS. 5 and 6, the newly installed lower piece 14 is suspended by a lifting device (not shown) such as a crane via a hanging frame 34 fixed to the lower piece, By engaging the joint fitting 24 of the lower piece 14 to be suspended with the joint fitting 24 of the existing lower piece 11 and lowering it, the groove hole 30
Insert inside. The height position of the lower piece 14 inserted into the slot hole 30 was measured with the tube bottom surface as a reference so that the tube bottom surface, that is, the inner surface of the bottom part 14b of the lower piece 14 coincided with the tube bottom surface of the existing lower piece 11. Afterwards, for example, in order to define the excavation area of the trench hole 30, prior to excavation, the hanging frame 34 is supported by a cross member 38 spanned over guide walls 36 (see FIG. 7) arranged parallel to each other on the ground surface. , the lower piece 14 is placed in the slot 30 and maintained at the height position.

The lower piece 14 and the hanging frame 34 have, for example, holes (not shown) through which the bolts 18 can pass.
are provided on the hanging frame 34, and the bolts 18 are screwed into the inserts 16 provided in the lower piece 14, and the nuts 15 are screwed onto the bolts, thereby making the connection possible.

After placing one lower piece 14 in the slot 30 filled with stabilizing liquid 28, or repeating said excavation of the slot and said placement of the lower piece into said slot, or placing two or more lower pieces. After digging a groove as long as possible and arranging a plurality of lower pieces in the groove, the opening of the lower piece 14 is opened so that the stabilizing liquid 28 does not flow between the inside and outside of the lower piece 14. Close all or part of.
When the water level of the stabilizing liquid 28 is at the same position as or above the upper end of the lower piece 14, the entire opening of the lower piece 14 located at the frontmost position, that is, the open upper end and the open end in the axial direction of the tube 10. and, if downward, close said open end which is part of the opening. However, even if the water level of the stabilizing liquid is below the upper end of the lower piece 14, this is not intended to prevent all of the openings from being closed.

In this example, the water level of the stabilizer is lower piece 1.
4, so that the open end can be secured by engaging the locking box 32 with the open end, as shown in FIGS. The open upper ends of the existing lower piece 11 and the lower piece 14 connected thereto are closed by a cover 40. By using the locking box, when the stabilizing liquid 28 described later is solidified, the lower piece 1
It is possible to prevent the stabilizing liquid 28 from entering the joint fitting 24 provided at the joint fitting 24 and solidifying.

Next, the stabilizing liquid 28 surrounding the lower piece 14 is solidified to support the lower piece 14 on the surrounding ground (FIG. 7). After a solidifying agent is added to the stabilizing liquid 28, it is stirred and mixed with the solidifying agent. This stirring can be performed by stirring the stabilizing liquid 28 or by air blowing, but a large number of bubbles are generated by either stirring.
The air bubbles below the lower piece 14 rise and form the lower piece 1
4, but rises further along an inclined surface 23 defining the outer surface of the bottom. The flat surfaces 25 between the slopes 23 have extremely short lengths in the cross section as described above, so the bubbles move toward the slopes 23 without remaining on the flat surfaces 25. Therefore, almost no air bubbles remain under the bottom of the lower piece 14, and after the stabilizing liquid 28 solidifies, the lower piece 14 remains in the solidified layer.
There are no voids that would reduce the supporting capacity of the In this way, the lower piece 14 is in the same state as the existing lower piece 11.

After the stabilizing liquid 28 is solidified, the hanging frame 34 is removed, and the stabilizing liquid in the lower pieces 11 and 14 between the partition gate 31 and the locking box 32 is extracted. Furthermore, the lower piece 11,
After the inner surfaces of the lower pieces 14 are dried, the joint grooves 26 (see FIG. 3) are filled with a bituminous joint material, and this is further covered with premix mortar to finish the surface between the inner surfaces of the lower piece. Since the upper end of the lower piece is open, it is possible to move in and out of the lower piece easily and smoothly, and the above-mentioned joint filling work in the lower piece can be performed easily, quickly and accurately. be able to.

Thereafter, the upper piece 12 is connected to the lower pieces 11 and 14 using the bolt 18 and nut 15.

In this way, after connecting the pipes 10 to form a pipe line over all sections, it is backfilled with earth and sand.

In addition, the outer surface of the bottom part 14b of the lower piece 14 is
A slope that slopes from one side 14a to the other side 14a, a pair of slopes that intersect at an angle, and three or more slopes such as those on the side surfaces of a prism. It can be defined by a curved surface whose surface or cross section is arcuate. In addition to concrete, the material of the pipe may be plastic or metal, which has a strength equal to or higher than that of concrete.

[Brief explanation of drawings]

Figure 1 is a front view of the pipe, Figures 2 and 3 are cross-sectional views taken along lines 2-2 and 3-3 in Figure 1, respectively, and Figure 4 is a section of the trench during excavation. 5 is a partial longitudinal sectional view of the slot when the lower piece is inserted into the stabilizing liquid; FIG. 6 is a partial longitudinal sectional view of the slot when the lower piece is placed; FIG. 7 is the lower tier. FIG. 6 is a cross-sectional view of the slot when the stabilizing liquid outside the piece is solidified. 10: Pipe, 11, 14: Lower piece (buried object for forming waterway), 12: Upper piece, 28: Stabilizing liquid,
30: Groove.

Claims (1)

[Claims] 1. A buried object for forming a waterway, which has a bottom that is convex downward, and the bottom has an outer surface including one or more inclined surfaces or curved surfaces.