JP4558595B2 - Installation method of underground tank and installation device of underground tank - Google Patents

Description

  The present invention is, for example, a precast type underground tank structure in which concrete parts are manufactured at a factory and assembled and installed at an installation site, and a method and apparatus for installing an underground tank for storing gasoline, kerosene, heavy oil, etc. It is about.

Conventionally, as this kind of underground tank structure, what is indicated by patent documents 1 is known. This underground tank structure is provided on the frame with a frame-shaped frame installed on the discarded concrete at the bottom of the installation hole, a tank installation part integrally formed on the frame, an underground tank installed on the tank installation part, and And a top board installed on the column part. When installing an underground tank structure in an installation hole, first, a grindstone is laid on the bottom of the installation hole, and discarded concrete is placed. Next, a frame is installed on the discarded concrete, and an underground tank is installed on the tank installation part of the frame. After that, concrete is placed in the enclosure and the surrounding area of the underground tank is surrounded by concrete. Furthermore, the installation of the underground tank structure is completed by installing the upper board on the support column of the frame and refilling the installation holes.
JP-A-6-73919 (pages 2 and 3)

  By the way, according to the Fire Service Law, this type of underground tank is determined to be installed at a position spaced apart by a certain distance (separation interval) inward from the peripheral wall of the rectangular box-shaped container. On the other hand, since the conventional underground tank is formed in a cylindrical shape, the width of the container needs to be a length obtained by adding twice the diameter of the underground tank and the separation interval. In this case, above or below the horizontal plane passing through the center of the underground tank, the distance from the peripheral wall to the inside of the container is not less than the spacing distance but is not used as an underground tank. For this reason, the underground tank must be enlarged correspondingly, and the container for accommodating the underground tank must also be enlarged, which has a problem of requiring an extra installation space.

  Therefore, in Japanese Patent Application No. 2004-191769, the present applicant provides an underground tank storage device that can reduce the installation space of the underground tank by downsizing the underground tank and the container that accommodates the underground tank. In the underground tank storage device, a reinforcing material is installed in the underground tank to withstand the concrete pouring pressure when the concrete is placed, and the reinforcing material can be taken out from the underground tank after the concrete is hardened. It has become.

  An object of the present invention is to prevent deformation of an underground tank after placing concrete by a novel means using gas pressure without employing such a reinforcing material.

The present invention will be described with reference to the drawings of the embodiments described later (the first embodiment shown in FIGS. 1 to 5 and the second embodiment shown in FIGS. 4 and 6).
In invention of Claim 1, the underground tank 2 is installed as follows.

The container 1 is provided in the installation hole 3 provided in the installation site, and the concrete 24 is placed around the underground tank 2 in the container 1 and solidified by placing the underground tank 2 in the container 1. . The inner dimension between the inner surfaces of the underground tank 2 where the deformation of the underground tank 2 is assumed to be the largest due to the placement of the concrete 24 is measured before the concrete 24 is placed and when the concrete 24 is placed. 2, according to the internal dimensions measured before the concrete 24 is placed and when the concrete 24 is placed, for example, the internal dimensions thereof are maintained against the pressure applied to the underground tank 2 by the concrete 24 placement. Apply gas pressure to For example, this gas pressure is commensurate with the pressure applied to the underground tank 2 by the placement of the concrete 24 and is substantially equal to the placement pressure of the concrete 24.

In the invention of claim 1, since the reinforcing material described in Japanese Patent Application No. 2004-191769 is not employed, the manufacturing cost of the underground tank structure can be kept low. Further, the reinforcing material does not get in the way during inspection work or cleaning work in the underground tank 2, and these work can be performed smoothly. Furthermore, since the gas pressure is applied according to the internal dimensions measured before the concrete 24 is placed and when the concrete 24 is placed, the internal dimensions of the underground tank 2 can be easily maintained in the state before the placement. it can.

In invention of Claim 2, the underground tank 2 is installed as follows.
In the installation hole 3 provided in the installation site, a container 1 is provided for accommodating the underground tank 2 that is arranged in a horizontal shape in a square tube shape. The container 1 includes a rectangular frame-shaped peripheral wall 5 provided so as to surround the underground tank 2, a base 6 provided at the bottom of the peripheral wall 5 to support the underground tank 2, and the peripheral wall 5. The upright column 7 and the upper slab 8 supported by the upper end of the column 7 are provided. The concrete 24 is placed around the underground tank 2 in the container 1 and solidified by placing the underground tank 2 on the foundation 6. The deformation of the underground tank 2 is assumed to be the greatest deformation due to the placement of the concrete 24, and the inner dimension between the intermediate portions of the opposite side walls 13 of the underground tank 2 is set before the concrete 24 and the concrete 24 is placed. The inner dimension is measured by the inner dimension detecting means 26, 27 at the time of installation, and the inner dimension is measured in the underground tank 2 by the inner dimension detecting means 26, 27 before and after the concrete 24 is placed. In response to this, a gas pressure is applied so as to maintain, for example, the inner dimensions thereof against the pressure applied to the underground tank 2 by placing the concrete 24. For example, this gas pressure is commensurate with the pressure applied to the underground tank 2 by the placement of the concrete 24 and is substantially equal to the placement pressure of the concrete 24.

In the invention of claim 2, since the reinforcing material described in Japanese Patent Application No. 2004-191769 is not employed, the manufacturing cost of the underground tank structure can be kept low. Further, the reinforcing material does not get in the way during inspection work or cleaning work in the underground tank 2, and these work can be performed smoothly. Furthermore, since the gas pressure is applied according to the internal dimensions measured before the concrete 24 is placed and when the concrete 24 is placed, the internal dimensions of the underground tank 2 can be easily maintained in the state before the placement. it can. By the way, since the underground tank 2 is arranged horizontally in a square tube shape, the underground tank 2 and the container 1 that accommodates the underground tank 2 can be downsized to reduce the installation space of the underground tank 2. . By the way, in such an underground tank structure having a leakage prevention structure, the main purpose is to prevent leakage from the underground tank 2 by the concrete 24, and therefore, it is obligated by the Fire Service Law to use the highly water-tight concrete 24. However, since such concrete 24 naturally increases in strength, in addition to such a main purpose, the surroundings of the underground tank 2 are reinforced to eliminate the adverse effects of earth pressure and water pressure on the underground tank 2. It also has the effect of doing. As a result, even in the underground tank 2 that is arranged horizontally in a square tube shape, the strength weakness of the underground tank 2 can be compensated by the concrete 24.

In the invention of Claim 3 based on the invention of Claim 1 or Claim 2 , the gas pressure is air pressure. In the invention of claim 3 , when water pressure is adopted, after the installation of the underground tank 2, it is necessary to extract water from the underground tank 2 or to clean the inside of the underground tank 2. The atmospheric air can be used as it is to be supplied into the underground tank 2 or the air in the underground tank 2 can be opened to the atmosphere as it is, and these operations are not required. Therefore, the installation work of the underground tank 2 can be easily performed. Moreover, the pressure adjustment in the underground tank 2 can be performed easily.

The underground tank installation apparatus according to the invention of claim 4 is used in the underground tank installation method according to the invention of claim 2, and the compressor 21 connected to the underground tank 2 and the concrete 24 are placed underground. and a inner size detection means 26, 27 in the relative direction both side walls 13 of the underground tank 2 the deformation of the tank 2 is assumed as the most increases reading by measuring the internal dimension between the middle portion, hitting the concrete 24 A gas pressure that opposes the pressure applied to the underground tank 2 by placing the concrete 24 is applied from the compressor 21 in accordance with the inner dimensions measured by the inner dimension detecting means 26 and 27 before the concrete 24 is placed. Is done.

In the invention of claim 4 , gas such as air can be easily supplied into the underground tank 2 by the compressor 21. Further, by using the inner dimension detection values read by the inner dimension detecting means 26 and 27, the inner dimension measured before placing the concrete 24 and the inner dimension measured when placing the concrete 24 are compared. Since the gas pressure is applied, the inner dimensions of the underground tank 2 can be easily maintained in the state before the placement.

An underground tank installation device according to a fifth aspect of the invention is used in the underground tank 2 installation method according to the second aspect of the invention, and includes gas pressure applying means 21 and 29 for applying a gas pressure to the underground tank 2. The inner dimension detecting means 26, 27 for measuring the inner dimension between the intermediate portions of the opposite side walls 13 of the underground tank 2 where the deformation of the underground tank 2 is assumed to be the largest due to the placement of the concrete 24, , a predetermined inside dimension setpoint dimension detection value among measured by internal dimension detecting means 26 and 27 striking設時concrete 24 (e.g. inner dimensions between intermediate portions of the relative direction both side walls 13 in the hitting設前concrete 24) And a control means 28 for driving and controlling the gas pressure applying means 21 and 29. For example, the inner dimension detection value and the predetermined inner dimension setting value are matched.

In invention of Claim 5 , the operation | work which maintains the inner dimension of the underground tank 2 in the state before placing can be performed automatically.

In the present invention, the deformation of the underground tank 2 after the concrete 24 is placed by simple means using the gas pressure applied according to the inner dimensions measured before the concrete 24 is placed and when the concrete 24 is placed. Can be prevented.

First, a first embodiment of the present invention will be described with reference to FIGS.
The underground tank structure shown in FIGS. 1 and 2 is a precast type product in which each part for constituting the container 1 and the underground tank 2 is separately manufactured at the factory and then transported to the installation site and assembled together. is there. The main body 4 of the container 1 shown in FIG. 3 is accommodated in the installation hole 3 provided at the installation site. The main body 4 of the container 1 includes a square frame-shaped peripheral wall 5, a plurality of bases 6 provided at the bottom of the peripheral wall 5, and a plurality of support columns 7 erected along the peripheral wall 5. ing. In addition to the main body 4, the container 1 includes an upper slab 8 that is supported by the upper ends of the columns 7. At the bottom of the installation hole 3, the discarded concrete 10 is cast on the laid stone 9 and solidified, and the peripheral wall 5 of the main body 4 of the container 1 is placed on the discarded concrete 10. Lattice reinforcing bars 11 are stretched between the concrete 10 and the foundations 6.

  As shown in FIGS. 1 and 2, in the underground tank 2 formed of a steel material such as stainless steel, both side walls 13 facing each other in the left-right direction Y, and a top wall 14 and a bottom wall 15 facing each other in the up-down direction Z, Accordingly, the outer peripheral wall 12 having a substantially rectangular tube shape extends in the front-rear direction X, and both end portions of the outer peripheral wall 12 in the front-rear direction X are closed by both end walls 16 facing each other in the front-rear direction X. Manholes 17 are provided on the top wall 14 of the outer peripheral wall 12 on both sides in the front-rear direction X, and both manholes 17 are covered with protectors 18 that prevent intrusion of earth and sand. The underground tank 2 is accommodated in the main body 4 in a state of being installed on the bases 6 by the container 1 and fixed to the bases 6 by bands 19. At that time, a concrete placement chamber 20 is provided between the underground tank 2 and the main body 4 of the container 1.

  After the underground tank 2 is accommodated in the main body 4 of the container 1 or before the underground tank 2 is accommodated in the main body 4 of the container 1, as shown in FIG. Then, air is supplied from the compressor 21 into the underground tank 2 while looking at the pressure gauge 23. In the underground tank 2, the air pressure (gas pressure) assumed in advance according to the placement pressure generated outside the underground tank 2 when it is assumed that the concrete is placed in the concrete placement chamber 20 or higher than that. A slightly higher air pressure is set. When air pressure is applied to the underground tank 2 before placing concrete in this way, as shown in FIG. 2, the side walls 13, the top wall 14, and the bottom wall 15 of the underground tank 2 bulge slightly outward. .

  Next, when the concrete 24 is placed in the concrete placement chamber 20 as shown in FIG. 5 with the air pressure rising in the underground tank 2, both side walls of the underground tank 2 are caused by the placement pressure of the concrete 24. 13, the top wall 14 and the bottom wall 15 are pushed inward and gradually approach a flat original state. At that time, since the volume in the underground tank 2 is slightly reduced and the air pressure in the underground tank 2 increases, the manual pressure control valve 25 attached to the manhole 17 is operated to gradually extract air from the underground tank 2. Then, the air pressure in the underground tank 2 is lowered to maintain the initial set air pressure before the concrete 24 is placed. Therefore, even if the casting pressure of the concrete 24 is applied to the outside of the underground tank 2, the air pressure in the underground tank 2 opposes the casting pressure and prevents deformation due to the casting pressure, so that the underground tank 2 The side walls 13, the top wall 14, and the bottom wall 15 can be kept flat. While the state is maintained, the concrete 24 is awaited to harden.

  After the concrete 24 is completely hardened, the underground tank 2 is opened to the atmosphere via the manual pressure control valve 25. When the concrete 24 is hardened, the pouring pressure applied to the outside of the underground tank 2 disappears, and the side walls 13, the top wall 14, and the bottom wall 15 of the underground tank 2 can be maintained in a flat original state. .

Next, a second embodiment of the present invention will be described with reference to FIGS.
The in underground tanks 2 inside dimension measuring device 26 as the inner dimension detecting means between the relative direction both side walls 13 underground tanks 2 are Installation. This internal dimension measuring device 26 is, for example, a light reflection type distance sensor, and is located between the middle portions of the opposite side walls 13 where the deformation of the underground tank 2 is assumed to be greatest, that is, in the longitudinal direction X of the side walls 13. The inner dimension between the side walls 13 is measured at the center and slightly below the center of the side walls 13 in the vertical direction Z. The signal from the internal dimension measuring device 26 is output to an indicator 27 as an internal dimension detecting means provided outside the underground tank 2, and the internal dimension detection value can be read and displayed by the indicator 27. .

  After the underground tank 2 is accommodated in the main body 4 of the container 1 or before the underground tank 2 is accommodated in the main body 4 of the container 1, the internal dimension between the side walls 13 is measured in advance by the internal dimension measuring device 26. Then, the internal dimension set value is stored in the controller 28 (control means) via the indicator 27.

  Thereafter, when air is supplied from the compressor 21 into the underground tank 2, the side walls 13, the top wall 14, and the bottom wall 15 of the underground tank 2 slightly bulge outward, and the inner dimension between the both side walls 13 is the inner dimension. It becomes larger than the set value.

  Next, when the concrete 24 is placed in the concrete placing chamber 20 with the air pressure rising in the underground tank 2, the both side walls 13, the top wall 14, and the bottom of the underground tank 2 are driven by the placement pressure of the concrete 24. The wall 15 is pushed inward and gradually approaches a flat original state. At this time, the automatic pressure control valve 29 and the compressor 21 attached to the manhole 17 are driven and controlled as gas pressure application means so that the internal dimension detection value is compared with the internal dimension setting value and they match each other. Therefore, the deformation due to the casting pressure of the concrete 24 can be prevented, and the side walls 13, the top wall 14, the bottom wall 15, particularly the both side walls 13 of the underground tank 2 can be kept flat. While the state is maintained, the concrete 24 is awaited to harden.

  After the concrete 24 is completely hardened, the underground tank 2 is opened to the atmosphere via the manual pressure control valve 25. The internal dimension measuring device 26 is removed from the underground tank 2. When the concrete 24 is hardened, the pouring pressure applied to the outside of the underground tank 2 disappears, and the side walls 13, the top wall 14, and the bottom wall 15 of the underground tank 2 can be maintained in a flat original state. .

  In addition to such automatic control, the manual pressure control valve 25 is operated while observing the internal dimension detection value displayed on the indicator 27 so that the internal dimension detection value matches the internal dimension setting value. Good.

It is sectional drawing which looked at the state before concrete placement in the underground tank structure concerning 1st Embodiment from the side wall side of the underground tank. It is sectional drawing which looked at the state before concrete placement in the above-mentioned underground tank structure from the end wall side of the underground tank. It is a perspective view which shows the main body of a container in said underground tank structure. It is the side view which looked at only an underground tank and its installation apparatus from the side wall side of an underground tank in said underground tank structure. It is sectional drawing which looked at the state after concrete placement in the above-mentioned underground tank structure from the end wall side of the underground tank. It is sectional drawing which looked at the state after concrete placement in the underground tank structure concerning 2nd Embodiment from the end wall side of the underground tank.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Container, 2 ... Underground tank, 3 ... Installation hole, 5 ... Perimeter wall, 6 ... Base stand, 7 ... Column, 8 ... Upper slab, 13 ... Side wall, 21 ... Compressor (gas pressure application means), 24 ... Concrete , 26 ... internal dimension measuring device (internal dimension detecting means), 27 ... indicator (internal dimension detecting means), 28 ... controller (control means), 29 ... automatic pressure control valve (gas pressure applying means).

Claims (5)

An installation method of an underground tank in which a container is provided in an installation hole provided at an installation site, and concrete is placed and solidified around the underground tank in the container with the underground tank installed in the container,
The inside dimension between the inner surfaces of underground tanks deformation of underground tanks by pouring is assumed that most increases the concrete was measured and hitting設時of hitting設前and concrete of the concrete, the said underground tank, concrete A method for installing an underground tank, characterized by applying a gas pressure that opposes the pressure applied to the underground tank by placing concrete according to the inner dimensions measured before placing the concrete and at the time of placing concrete. In the installation hole provided at the installation site, a container for accommodating an underground tank that is horizontally placed in a rectangular tube shape is provided, and this container is a square frame provided to surround the underground tank A base that is provided at the bottom of the peripheral wall and supports the underground tank, a column that is erected along the peripheral wall, and an upper slab that is supported by the upper end of the column. A method for installing an underground tank in which concrete is placed around the underground tank in the container while the underground tank is installed on a table, and solidified.
It is assumed that the deformation of the underground tank will be the largest due to the placement of the concrete, and the inner dimensions between the opposite side walls of the underground tank are the inner dimensions before and after the concrete placement. Measured by the detecting means, and in the underground tank, the pressure applied to the underground tank by placing concrete according to the inner dimensions measured by the inner dimension detecting means before and after placing the concrete. A method of installing an underground tank, characterized by applying a counter gas pressure. 3. The underground tank installation method according to claim 1 , wherein the gas pressure is air pressure. An underground tank installation apparatus used in the underground tank installation method according to claim 2, wherein the underground tank is assumed to have the greatest deformation due to the compressor connected to the underground tank and the placement of the concrete. An internal dimension detecting means for measuring and reading the internal dimension between the opposite side walls of the tank, and in the underground tank before and after the concrete is placed . An apparatus for installing an underground tank, wherein a gas pressure that opposes the pressure applied to the underground tank by placing concrete is applied from the compressor in accordance with the internal dimension measured by the dimension detecting means. An underground tank installation device used in the underground tank installation method according to claim 2, further comprising gas pressure applying means for applying a gas pressure to the underground tank, wherein the underground tank is most deformed by placing the concrete. The inner dimension detection means for measuring the inner dimension between the middle parts of the opposite side walls of the underground tank, which is assumed to be large, and the inner dimension detection value measured by the inner dimension detection means when placing concrete An apparatus for installing an underground tank, comprising control means for driving and controlling the gas pressure applying means in comparison with a dimension setting value.

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