JP2005054428A - Inspection pit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-cost inspection pit which can be constructed in a short construction period, and which hardly requires a traffic restriction. <P>SOLUTION: This inspection pit is surrounded by four side surface plates, and a top surface plate which is provided with an opening 11 for entrance/exit of a person; a lower edge of the side surface plate is provided with a notch 12 into which piping 1 to be buried in ground can be inserted; and the inspection pit comprises a bottom part 9 for closing a lower opening 6 of an upper frame 8, two closing plates 10 for the notch 12, whose edges are provided with indented parts 18 into which a cross-sectional semicircle of the piping 1 can be fitted, and an openable/closable lid for the upper opening 11 of the upper frame 8. The inspection pit is formed as follows: a foundation below the piping 1 is consolidated; the bottom part 9 is installed thereon; the upper frame 8 is lowered astride the piping 1 at a position of the notch 12; the lower opening 6 of the upper frame 8 and the bottom part 9 are engaged with each other; the piping 1 is sandwiched in such a manner that the indented parts 18 of the closing plates 10 face each other; the notch 12 is closed; the closing plates 10 are fixed to a peripheral edge of the notch 12 by means of a locking implement; and the upper opening 11 of the upper frame 8 is covered with the lid. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an inspection pit for pipes of fluid such as water, gas, sewage and chemicals buried underground.

The inspection pit is a cavity that allows a person to go in and out by digging soil at a desired location of the buried pipe and attaching a meter or strainer to the pipe.
Conventionally, as shown in FIG. 10, a lightweight steel sheet pile 2 is first driven around the pipe 1, the soil surrounded by the sheet pile 2 is excavated, a large hole is provided, and a basic crushed stone 3 is placed below the pipe 1. Lay the foundation, and lay the foundation concrete 4 on it.
Next, the reinforcing bars are surrounded by a frame plate on the spread concrete 4 so that the pipe 1 penetrates in the lower part, and a box-shaped reinforced concrete frame 5 is provided by concrete casting (see Non-Patent Document 1).
An opening 6 is provided in the upper part of the reinforced concrete frame 5 for people to enter and exit.
Although not shown, the opening 6 is provided with a lid.
Finally, the opening 6 is removed and the periphery of the reinforced concrete frame 5 is filled with soil, and the sheet pile 2 is pulled out.
An inspection pit is completed by attaching an instrument, a strainer or the like to the pipe 1 in the reinforced concrete frame 5.
Architectural Glossary (Gihodo Sho 53, 11, 1 issue, 1 edition, 12 prints), page 909, section of reinforced concrete.

The conventional inspection pit requires a considerable number of days (20 days on average) to form the reinforced concrete frame 5 by concrete and laying of the spread concrete 4, the reinforcement structure and the concrete pouring.
Meanwhile, traffic is restricted during construction. In addition, since the construction period is long, the labor cost is high, and the cost of transporting concrete-carrying materials and equipment is also high, which is expensive.
An object of the present invention is to provide an inspection pit that can be constructed in a short number of days, does not limit traffic, and is inexpensive.

Surrounded by four side plates and a top plate provided with an opening through which people can go in and out, provided a notch through which underground piping can be inserted in the lower edge of the two side plates facing each other, The lower part is an upper frame having at least the opening between the notches, and
A bottom for closing the lower opening of the upper frame;
Two notched blocking plates provided with a bay portion capable of fitting a semicircle of the cross section of the pipe at the edge;
An openable / closable lid for the upper opening of the upper frame;
And digging out the top, bottom, left, and right soils of the buried pipe in the ground to make holes, solidifying the bottom of the pipe, placing the bottom on the solidified surface, and placing the upper frame The lower opening of the upper frame and the bottom portion are engaged with each other at the notch, fixed with a locking tool, and two of the closing plates are used as one set. Each set of two closed plate bay entry portions are opposed to each other, the piping is sandwiched between them, and the notches are closed by contacting the respective peripheral edges of the two cutouts of the upper frame. Is fixed with a locking tool, the opening above the upper frame is covered, and the periphery of the upper frame is backfilled with soil to form an inspection pit.

The concrete construction can be done only with spread concrete, and the construction period is about 5 days on average, which can be greatly shortened compared to the conventional one.
Since concrete construction is only spread concrete, there is no need for materials such as reinforcing bars and form plates required for rebar assembly, and concrete materials can be greatly reduced, so there is no need for labor, material costs, transportation costs, and the construction period is long. The labor cost is low because it is short. Therefore, the construction cost can be greatly reduced. In addition, quality is stable due to factory production and on-site assembly.
Because the construction period is short, traffic is not restricted so much.

The inspection pit is composed of four parts: an upper frame 8, a bottom 9, a cutout closing plate 10, 10 and a lid (not shown).
All of the above members are formed of a lightweight concrete plate, a plastic plate, a stainless steel plate or the like. The lid may be made of a casting.

The upper frame 8 is a box having an opening 6 at the bottom, and has an opening 11 through which the person can go in and out of the upper plate, and a notch 12 through which the pipe 1 can be penetrated on opposite side surfaces.
The notch 12 has an arch shape such as a corner or a circle.
Below the upper frame 8, an opening (symbol 6 in the drawing) is provided between at least two notches 12 and 12.
As a means for engaging the upper frame 8 and the bottom portion 9, a shelf 13 that abuts on the step portion 15 of the bottom portion 9 is provided in the lower part of the box, and can be locked with bolts.

  The bottom portion 9 is a member that closes the opening 6 below the upper frame 8, is provided with step portions 15 on both side edges of the upper surface of the bottom plate 14, and is fitted on the other side edges to the lower portion of the notch 12 of the upper frame 8. The vertical pieces 16, 16 are erected, and the vertical pieces 16, 16 are provided with a stepped portion 17 facing each other at the lower portion, and can be fitted to the stepped portion at the lower end of the closing plate 10.

  The closing plate 10 is provided with a baying portion 18 that can fit the semi-periphery of the piping 1 on one side, the piping 1 is sandwiched with the baying portions 18 of the two closing plates 10 and 10 facing each other, and a lower step of the closing plate 10. The bottom 17 is fitted and engaged with the step 17 of the vertical piece 16 on the bottom 9, the lower end is placed on the shelf 13 of the upper frame 8, and the upper frame 8 is secured with a locking tool such as a bolt and nut (not shown). It fixes to a side plate and the vertical piece 16, and the notch 12 of the upper frame 8 can be obstruct | occluded.

The construction of the inspection pit will be described with reference to FIGS.
First, the sheet pile 7 is driven and enclosed at the position where the inspection pit is to be constructed, and the soil at the enclosed area is dug out.

The foundation is fixed below the exposed pipe 1.
The foundation is solidified by laying the ground crushed stone 3 and the spread concrete 4 thereon.
Either the basic crushed stone 3 or the spread concrete 4 may be omitted.
The bottom portion 9 is installed on the surface of the foundation below the pipe which has been solidified by adjusting the height.
The upper frame 8 is lowered onto the bottom 9 and the lower surface of the shelf 13 of the upper frame 8 is brought into contact with the step 15 of the bottom 9 so that the upper frame 8 and the bottom 9 are engaged with each other. The part 15 is fixed with a locking tool such as a bolt and a nut (not shown).

  Next, the piping 1 is sandwiched with the baying portions of the two blocking plates 10 facing each other, the peripheral portions of both the blocking plates 10 are brought into contact with the inner peripheral surfaces of the notches 12 of the upper frame, and the lower ends of the both blocking plates 10 are The step portion is fitted to the step portion 17 of the vertical piece 16 of the bottom portion 9 and placed on the upper surface of the bottom plate 14 of the bottom portion 9. Nine vertical pieces 16 are fixed with a locking tool such as a bolt and a nut (not shown).

An openable / closable lid (not shown) is attached to the opening 11 of the upper frame 8, soil is filled in the hole surrounded by the sheet pile 7, and the sheet pile is pulled out.
The road surface around the opening 11 is restored by paving, etc., and returned to the original state.
Opening the lid, going in and out, attaching gauges etc. to the piping, it becomes possible to inspect the piping.

  It is preferable that a packing is fitted to a contact portion between the upper frame 8 and the bottom portion 9 and a contact portion between the closing plate 10 and the upper frame 8, the bottom portion 9 and the pipe 1.

  In the above embodiment, the upper frame 8, the bottom 9, and the closing plate 10 can be coupled and fixed in the inspection pit by using bolts and nuts and the like, so that the space between the sheet pile 7 and the outer surface of the upper frame 8 can be reduced. There is no need to dig a lot of soil and less soil excavation.

Instead of providing the step portion 17 on the vertical piece 16 of the bottom portion 9, as shown in FIG. 6A, a bottom portion 9a provided with the vertical piece 16a may be used.
When the bottom 9a is used, although not shown, the closing plate 10 is brought into contact with the inner surface of the vertical piece 16a across the pipe 1, the lower end is placed on the bottom surface 14, and the notch 12 is closed. It fixes to the side of the vertical piece 16a and the upper frame 8 with locking tools, such as a volt | bolt and a nut.

As shown in FIG. 6 (B), a bottom surface 9b having a convex side surface without the vertical pieces 16, 16a may be used.
In the case of using this bottom portion 9b, although not shown, the piping 1 is sandwiched between the two closing plates 10, the notch 12 is closed, and the inner surface of the upper frame 8 at the periphery of the notch 12 is contacted. The lower end is placed on the bottom surface and fixed to the side surface of the upper frame 8 with a locking tool such as a bolt and a nut.

  As shown in FIG. 7, the upper frame 8 a, that is, notches on both sides, except for the shelf 13 of the upper frame 8, using a dish-shaped bottom portion 9 c provided with an annular protruding edge 20 on the periphery of the bottom surface of the bottom plate 19. 12 is used, and the upper frame 8a having an opening on the lower surface and the opening 11 on the upper surface is used. Then, the side surfaces of the protruding edge 20 and the upper frame 8a are fixed with locking tools such as bolts and nuts (not shown), and a step portion 17 is provided on the inner surface side of the protruding edge 20 on the notch 12 side. Also provided at the edge is a step portion opposed to the step portion 17 of the protruding edge 20, the closing plate 10 and the protruding edge 20 are engaged with each other at the both step portions, and the upper plate 8 a is locked with a locking tool such as a bolt and a nut. It may be fixed to the side plate and the protruding edge 20. In addition, the lower end surface of the closing plate 10 may be brought into contact with the upper surface of the protruding edge 20 without providing a step portion on the protruding edge 20 and the closing plate 10.

  As shown in FIG. 8, a bottom portion 9d and a top frame 8a each having only a bottom plate are used, and the bottom portion 9d is fitted into a lower opening of the top frame 8a and fixed with a locking tool such as a bolt and a nut (not shown). The closing plate 10 may sandwich the pipe 1 and the notch 12 may be closed, and may be fixed with a locking tool such as a bolt and a nut at a contact portion between the lower end portion of the side plate of the upper frame 8a and the bottom portion 9d.

Although the closing plate 10 is fixed to the inner surface of the upper frame 8a in FIG. 8, it may be fixed to the outer surface of the upper frame 8a as shown in FIG.
1 to 4, the closing plate 10 may be fixed to the outer surface of the upper frame 8. When the closing plate 10 is fixed to the outer surface, the space between the outer surface of the upper frame and the sheet pile needs to be slightly widened so that a person can enter and work easily.

It is a perspective view of an upper frame. It is a perspective view of a bottom part. It is construction explanatory drawing which crossed the inspection pit at right angles to piping. It is construction explanatory drawing which cut | disconnected the inspection pit in parallel with piping. It is a perspective view of an inspection pit. It is a perspective view of the bottom part of other embodiment. (A) is parallel with piping, (B) is sectional drawing of a right angle of the inspection pit of other embodiment. (A) is parallel with piping, (B) is sectional drawing of a right angle of the inspection pit of other embodiment. (A) is parallel with piping, (B) is sectional drawing of a right angle of the inspection pit of other embodiment. It is construction explanation sectional drawing of the conventional inspection pit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Piping 2 Lightweight steel sheet pile 3 Basic crushed stone 4 Laying concrete 5 Reinforced concrete frame 6 Opening 7 Sheet pile 8 Upper frame 9 Bottom part 10 Blocking board 11 Opening 12 Notch 13 Shelf 14 Bottom board 15 Step part 16 Vertical piece 17 Step part 18 Bay part 19 Bottom plate 20 ridge

Claims (1)

Surrounded by four side plates and a top plate provided with an opening through which people can go in and out, provided a notch through which underground piping can be inserted in the lower edge of the two side plates facing each other, The lower part is an upper frame having at least the opening between the notches, and
A bottom for closing the lower opening of the upper frame;
Two notched blocking plates provided with a bay portion capable of fitting a semicircle of the cross section of the pipe at the edge;
An openable / closable lid for the upper opening of the upper frame;
And digging out the top, bottom, left, and right soils of the buried pipe in the ground to make holes, solidifying the bottom of the pipe, placing the bottom on the solidified surface, and placing the upper frame The lower opening of the upper frame and the bottom portion are engaged with each other at the notch, fixed with a locking tool, and two of the closing plates are used as one set. Each set of two closed plate bay entry portions are opposed to each other, the piping is sandwiched between them, and the notches are closed by contacting the respective peripheral edges of the two cutouts of the upper frame. The inspection pit is formed by fixing the top with an anchor, covering the opening above the upper frame, and backfilling the periphery of the upper frame with soil.

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