JP2001241287A - Construction method of shaft, assembly method of structural body used for construction method, and assembly device used for assembly method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To economically construct an underground storage tank without any auxiliary construction methods even under conditions where an excavation wall surface is not self-supportable and there is a spring. SOLUTION: An excavation guide earth retaining wall 20 is provided within a range where an excavation wall surface can self-support, and surrounded by concrete 21. Muddy water is introduced into the retaining wall 20, and a nearly circular pit is excavated in the muddy water excavation system. A shaft is excavated while muddy water 23 corresponding to the amount of excavation soil is being replenished into the pit. An assembled storage structural body 10 is suspended in the muddy water 23 of a pit 22 where muddy water excavation has been completed. Concrete is placed into a bottom part through a tremie pipe 26, thus forming base concrete 27. A hardener 29 is injected into the gap between the outer-periphery surface of the storage structural body 10 and an excavation wall surface. Overflowing muddy water is discharged by a pump. After conforming the consolidation of the base concrete 27 and the hardener 29 being injected between the storage structure body 10 and the excavation wall, muddy water in the water storage layer is discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a shaft by excavating a shaft in the ground, installing and fixing a cylindrical structure in the shaft, and a method of assembling a structure used in the method. And an assembling apparatus used in the assembling method.

[0002]

2. Description of the Related Art As a method of constructing a storage tank formed underground for the purpose of water storage or the like, there is known a method of using a liner plate 1 shown in FIGS. 16 to 18 and performing a procedure shown in FIGS. ing.

First, as shown in FIG. 16, a liner plate 1 is a generally steel segment obtained by equally dividing a cylindrical shape in a circumferential direction and a height direction. In this case, the liner plate 1 is assembled by civil engineering and construction work. It is used as a retaining frame to prevent collapse of the excavated wall. The liner plate 1 has a reinforcing plate 1b having a corrugated cross section inside a steel frame 1a.
Are fixed, and a bolt hole 1c for connection is formed in the frame 1a.

In an example shown in FIGS. 17 and 18, a ring-shaped structure obtained by cutting a cylindrical body perpendicularly to an axis has a central angle of 90 °.
Are assembled by connecting the four liner plates 1 having curved surfaces with bolts.

Next, a method of constructing a conventional underground storage tank using the liner plate 1 will be described. The ground surface is excavated as shown in FIG. The diameter of the hole 100 is larger than the outer shape of the ring-shaped structure in which the liner plate 1 can be assembled, and the depth thereof is equivalent to the height of the liner plate 1.

Next, as shown in FIG. 19B, the first-stage liner plate 1 is assembled in the hole, and the space between the liner plate 1 and the excavation wall of the hole 100 is fixed with concrete 101. This concrete 101 is called headband concrete.

Next, as shown in FIG. 19C, a space 1 enough to assemble the second-stage liner plate 1 is provided.
Excavate 02.

Next, as shown in FIGS. 19D and 20A, the second-stage liner plate 1 is assembled in the hole.

Next, as shown in FIG. 20B, the third-stage liner plate 1 is assembled in the hole by the same procedure.

In this manner, a liner plate structure 103 having a predetermined depth is constructed as shown in FIG.

As shown in FIGS. 21 (a) and 21 (b), a filler 104 such as mortar or concrete is filled in the gap between the overburden portion of the shaft and the liner plate 1, and concrete is filled at the bottom of the shaft. The base concrete 105 which is poured into a considerable thickness to prevent groundwater from being blown up is constructed.

[0012]

In the conventional construction method, the condition that the excavation wall surface is hard to collapse by itself and that there is no spring water is a condition for enabling the construction. If these conditions are not satisfied, for example, a ground improvement by injecting a chemical solution or an excavation auxiliary method such as digging a deep well around the excavation position to lower the groundwater level is required, which is uneconomical.

The present invention provides a method and a method for constructing a shaft which can be economically constructed without an auxiliary construction method for a shaft which can be used as an underground storage tank even under conditions where the excavation wall surface is difficult to stand by itself and spring water is present. An object of the present invention is to provide a method of assembling a structure used in the method and an assembling apparatus used in the method.

[0014]

According to a first aspect of the present invention, there is provided a method for constructing a vertical shaft, wherein the vertical shaft is constructed by applying mud pressure to a wall surface.
2) excavating a hole, assembling a structure (storage tank structure 10) on the ground, and installing and fixing the assembled structure in the shaft.

According to a second aspect of the present invention, there is provided a method for constructing a shaft.
A step of excavating a shaft (22) while applying muddy water pressure to a wall surface, a step of assembling a cylindrical structure (storage tank structure 10) having a smaller diameter than the shaft and opening vertically, and a step of assembling the assembled structure and the shaft Installing the structure in the shaft such that a gap is formed between the structure and the inner surface of the shaft, and introducing a solidifying material (29) between the outer surface of the structure and the wall surface of the shaft and at the bottom of the shaft. While discharging the muddy water to fix the structure in the shaft.

According to a third aspect of the present invention, there is provided a method for constructing a shaft.
3. The shaft construction method according to claim 2, wherein a reinforcing member (reinforcing net 24) is fixed to an opening at the bottom of the structure (storage tank structure 10), and is formed at a lower portion of the shaft by the solidified material (29). It is characterized in that the base (base concrete 27) is reinforced.

According to a fourth aspect of the present invention, there is provided a method of assembling a cylindrical structure (storage tank structure 10) which is installed in a shaft (22) and which is open at the top and bottom, in the circumferential direction and the height direction. A step of forming the first stage by connecting the divided segments (liner plate 1) in the circumferential direction at the assembling position, and lifting the first stage at a position higher than the height of the segment at the assembling position Connecting the segments to the lower part of the first stage and connecting them in the circumferential direction to form a second stage.

The structure (storage tank structure 1) according to claim 5
The assembling apparatus (2) of (0) is an assembling apparatus for assembling a cylindrical structure having upper and lower openings by connecting segments (liner plate 1) divided in a circumferential direction and a height direction. An assembly table (3) having a segment assembling position, a work hole (4) formed in the center for providing a work space for an operator, and the assembly table for supporting the assembly table at a predetermined height; A supporting leg (5) provided on the lower surface of the assembly, a plurality of columns (6) erected on the upper surface of the assembling table at intervals in the circumferential direction outside the assembling position, and A height that is greater than the height and is provided to be rotatable with respect to the post on the assembly table, and that the segments are circumferentially connected at the assembly position to form an assembly. When standing, it is set to an outer position that does not intersect the assembly position, and when supporting a step composed of a plurality of the segments connected in the circumferential direction, it is set to an inner position that intersects the assembly position. And a spacer (7) for forming a space on the lower surface of the step to connect the segment of the next step, and a lifting means (lifting device 8) for lifting the segment connected on the assembly stand.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present embodiment relates to a method for assembling the above-mentioned liner plate 1 into a cylindrical storage tank structure, and installing this in a vertical shaft excavated by a muddy water excavation method described later to construct a water tank underground. It is. Further, there is also a feature in the method of assembling the storage tank structure used in this construction method, and in the assembling apparatus used in assembling the storage tank structure.
These will also be described in detail.

First, a method of assembling a cylindrical storage tank structure by connecting the liner plates 1 and an apparatus 2 used in this assembling method will be described with reference to FIGS. The assembling apparatus 2 for a storage tank structure shown in FIGS. 1 to 3 has a flat plate-shaped assembling table 3. The assembling table 3 of the present example has a substantially octagonal shape, but any other shape may be used as long as it does not hinder assembly of the cylindrical storage tank structure thereon. Note that the assembling table 3 of the present example is made of a steel plate. The assembling position for assembling the liner plate 1 is as follows.
A work hole 4 is formed in the center of the assembling table 3 in order to provide a working space for a worker who performs this assembling operation. The working hole 4 in this example is square, but may be circular.

Four supporting legs 5 are attached to the lower surface of the assembling table 3 at equal intervals in the circumferential direction, and the assembling table 3 can be supported at a predetermined height on the ground like a table. . An operator can enter and exit the work hole 4 between the assembly table 3 and the ground.

On the upper surface of the assembling table 3, three columns 6 are attached at equal intervals in the circumferential direction. FIG.
The plan view of the assembled cylindrical storage tank structure 10 is
Although shown as a circle by imaginary lines, each column 6 is located outside the storage tank structure 10, that is, outside the position where the storage tank structure 10 is assembled.

A spacer 7 is attached to each of the columns 6. The spacer 7 is a member for mounting the storage tank structure 10 during assembly and temporarily holding the storage tank structure 10 at a predetermined position on the assembly table 3. The spacer 7
This is a block having a height greater than the height of one liner plate 1, and is provided rotatably with respect to the support column 6 on the assembly stand 3. When assembling the liner plate 1 at the assembling position as shown by a broken line in FIG. 1, the spacer 7 is set at an outer position not intersecting the assembling position. Further, when the plurality of liner plates 1 connected in the circumferential direction are lifted and temporarily held, the liner plates 1 are set at an inner position crossing the assembly position as shown by a solid line in FIG. As a result, there is a space below the annular liner plate 1 (the storage tank structure 10 in the course of assembly) placed on the spacer 7, enough to carry in and assemble the next-stage liner plate 1.

A lifting device of a truck crane (not shown) is used as a lifting means for lifting the liner plate 1 connected in a ring shape on the assembly stand 3. As shown in FIG. 3, a hanging girder 9 is connected to a hanging member 8 (made of a wire rope) connected to the hoisting device. The liner plate 1 connected in a circular shape can be suspended from the suspension girders 9 by suspension bolts 11. The level (horizontal level) of the suspended liner plate 1 can be finely adjusted by turning the suspension bolt 11 to change the protruding length from the suspension girder 9. As a result, the weight applied to the suspension bolts 11 is averaged, and the suspended ring-shaped liner plate 1 becomes horizontal.

Next, a method of assembling the liner plate 1 using the assembling apparatus 2 will be described. First, the spacer 7 is set at the outer position in FIGS. 1 and 2, and the first stage of the liner plate 1 is assembled at the assembly position on the assembly table 3. The worker enters the work hole 4 of the assembly table 3 to perform work. A waterproof packing is interposed between the liner plates 1 to be connected.

Next, as shown in FIG. 3, the hoisting device is operated to suspend the suspension girder 9 above the assembling device 2. Then, the suspension bolts 11 of the suspension girders 9 are attached to the assembly table 3.
Connect to upper liner plate 1.

Next, as shown in FIG. 4, the winding device is driven to lift the liner plate 1. Although the liner plate 1 having only one stage does not necessarily have high rigidity,
Since the suspension girder 9 is fixed to the suspension girder 9 with a plurality of suspension bolts 11, it is not deformed by an external force applied during lifting. The first-stage liner plate 1 is lifted higher than the spacer 7, and in this state, the spacer 7 is rotated to the inner position, and then the liner plate 1 is lowered and placed on the spacer 7 (temporary placement). ).

In the state shown in FIG. 4, there is a gap between the first-stage liner plate 1 and the assembling table 3 so that the liner plates 1 which are not assembled in a segment can be inserted one by one. As shown by arrows in FIG. 4, the liner plates 1 are inserted one by one from this gap, and the second-stage liner plate 1 is joined with bolts under the first-stage liner plate 1 at an assembly position where there is no spacer 7. . After connecting the second-stage liner plate 1 to the portion of the first-stage liner plate 1 that is not in contact with the spacer 7, turn the spacer 7 to the outside position and connect the second-stage liner plate 1 to the remaining portion. I do.

In the same procedure as shown in FIGS.
The liner plates 1 after the first stage are also assembled. FIG.
Shows the third stage assembly. This operation is repeated until a required height is obtained, and a cylindrical storage tank structure 10 having a required height as shown in FIG. 7 is assembled.

Next, a method of constructing a water storage tank underground using the cylindrical storage tank structure 10 will be described with reference to FIGS. First, as shown in FIGS. 8 to 10, a substantially circular shaft is excavated from the ground surface by a muddy water excavation method. FIG.
As shown in (1), the excavation guide earth retaining member 20 is constructed in a range in which the excavation wall can stand on its own. The excavation guide retaining clasp 20 is composed of an assembled liner plate having a diameter larger than that of the storage tank structure 10 described above. Therefore, this excavation guide earth retaining 2
The assembled tank structure 10 can be inserted into the space 0. A headband concrete 21 is provided around the first stage of this assembly.

The headband concrete 21 has a function of stabilizing and fixing the liner plate of the excavation guide earth retaining member 20. Further, as will be described later, after excavation, the storage tank structure 10
Is installed in the shaft and connected to the liner plate of the excavation guide retaining device 20, so that the upper excavating guide retaining device 20 adds a large weight. The headband concrete 21 prevents the upper excavation guide retaining clasp 20 from sinking due to this weight. Further, as will be described later, the shaft excavation employs a muddy water excavation method in which the inside of the shaft is filled with muddy water. The headband concrete 21 prevents the excavation wall from being scoured by waves generated on the surface of the muddy water in the pit during excavation.

In the state shown in FIG. 8, inside the shaft 22 (ie, inside the annular liner plate of the excavation guide retaining 20).
Muddy water 23 is charged. Here, excavation is started from the bottom in the shaft 22. The inner diameter of the shaft 22 to be excavated is smaller than that of the ring-shaped excavation guide retaining clasp 20 and larger than the outer diameter of the storage tank structure 10. Digging down while replenishing the pit with muddy water 23 corresponding to the excavated soil volume. The water level of the muddy water 23 is maintained at 2.0 m or more higher than the groundwater level, and the mud pressure prevents the excavation wall from collapsing.

As the muddy water 23, one having a concentration and viscosity that does not escape from gaps in the excavated soil layer is used. When left naturally, it is necessary that soil particles and the like in the muddy water do not precipitate and separate into individual liquids. Such muddy water can be produced, for example, by mixing an appropriate amount of bentonite, clay, or the like with water. The mud is made by mixing with a mixer near the excavation point.

As shown in FIG. 10, excavation is performed while replenishing the muddy water 23 to a required predetermined depth. During the excavation, the excavation wall is prevented from collapsing by the water pressure of the muddy water 23. When muddy water is excavated, sediment accumulates on the bottom surface of the shaft 22. After excavation is complete, carry them out with a bucket, etc.
Slime and the like are removed by vacuum or air lift. This completes the excavation work.

The excavation means for excavating the muddy water is not particularly limited. For example, if the excavation is relatively shallow, a backhoe is appropriate, and if it is deep, a clamshell is appropriate.

As shown in FIGS. 11 and 12, the assembled storage tank structure 10 is hoisted by a hoisting device of a truck crane, and the mud 2
3 hang and install. Before installation in the muddy water 23, a reinforcing net 24 is fixed as a reinforcing material to the open bottom of the storage tank structure 10.

As shown in FIG. 11, the storage tank structure 10 is not placed on the bottom of the shaft 22, but is suspended at a position slightly above the bottom with an appropriate distance from the bottom. The distance between the storage tank structure 10 and the bottom surface is determined by the thickness of the base concrete to be formed at this position. The thickness of the base concrete needs to be strong enough to withstand the water pressure applied to the bottom of the water storage tank and not to cause water leakage. As described above, if the reinforcing net 24 is provided, the strength of the base concrete is improved. Therefore, if the required strength is the same, the thickness of the concrete to be cast can be small.

As shown in FIGS. 11 and 12, in order to suspend the storage tank structure 10 at a position spaced from the bottom of the shaft 22, the suspension girder 9 in which the storage tank structure 10 is suspended by the suspension bolts 11 is attached to the head concrete 21. Adjustable pillow material 2 installed on
Place on top of 5. By appropriately adjusting the height of the adjustment pillow material 25, the interval can be arbitrarily set.

Since a filler is injected between the excavation wall surface and the outer peripheral surface of the storage tank structure 10 as will be described later, an annular projection projecting outward from the storage tank structure 10 By providing the spacer, the interval between the excavation wall surface and the outer peripheral surface of the storage tank structure 10 may be appropriately maintained.

As shown in FIG. 13, a concrete charging pipe 26 for underwater concrete casting (tremie pipe 26) is installed in the storage tank structure 10 and concrete is poured into the bottom to form a base concrete 27. Muddy water that overflows due to the introduction of concrete is discharged by the pump 28.

As shown in FIG. 14, the clearance between the outer peripheral surface of the storage tank structure 10 and the excavation wall surface (excessive clearance portion)
Then, a solidifying material 29 is injected as a filler. In this example, cement milk, mortar, concrete, and the like are used. The injection pipe 30 used at this time is inserted into the gap between the outer peripheral surface of the storage tank structure 10 and the excavation wall surface, and is inserted to the bottom. Excess muddy water is discharged by the pump 31 simultaneously with the injection of the solidified material. As the solidified material is evenly injected into the outer peripheral surface side of the storage tank structure 10,
The injection is performed while changing the position of the injection tube 30. Further, the injection pipe 30 is pulled up in parallel with the filling of the outer peripheral surface side of the storage tank structure 10 in accordance with the injection amount of the solidified material 29.

As shown in FIG. 15, the upper excavation guide retaining clasp 20 is removed, and a solidifying material (concrete or the like) is poured into the formed gap to remove the headband concrete 21 and the storage tank structure 1.
Join 0. Base concrete 27 and storage tank structure 1
After confirming the solidification of the solidified material 29 injected between 0 and the excavation wall, the muddy water in the reservoir is discharged.

Although the above-described example relates to the construction of an underground water storage tank suitable for storing rainwater and the like, the present invention relates to a vertical shaft of a propulsion method, a structure basic shaft, a purified water tank, an underground warehouse, and the like. It can be widely applied to the construction of a space for any use provided underground.

[0044]

According to the present invention, a shaft is excavated while applying muddy water pressure to a wall surface, and a structure assembled in advance on the ground is installed and fixed in the shaft, so that the excavated wall surface is hardly self-sustaining and spring water is generated. Under certain conditions, shafts that can be used for underground storage tanks and the like can be constructed economically without auxiliary methods.

[Brief description of the drawings]

FIG. 1 is a plan view of an assembling apparatus 2 for a storage tank structure 10 according to an embodiment of the present invention.

FIG. 2 is a side view of the assembling apparatus 2 of the storage tank structure 10 according to the embodiment of the present invention.

FIG. 3 is a diagram illustrating an assembling process of the storage tank structure 10 according to the embodiment of the present invention.

FIG. 4 is a view illustrating an assembling process of the storage tank structure 10 according to the embodiment of the present invention.

FIG. 5 is a diagram showing a process of assembling the storage tank structure 10 according to the embodiment of the present invention.

FIG. 6 is a view showing an assembling process of the storage tank structure 10 according to the embodiment of the present invention.

FIG. 7 is a diagram showing a process of assembling the storage tank structure 10 according to the embodiment of the present invention.

FIG. 8 is a diagram showing a construction process of an underground water storage tank according to the embodiment of the present invention.

FIG. 9 is a diagram showing a construction process of an underground water storage tank according to the embodiment of the present invention.

FIG. 10 is a diagram showing a construction process of an underground water storage tank according to the embodiment of the present invention.

FIG. 11 is a diagram showing a construction process of an underground water storage tank in the embodiment of the present invention.

FIG. 12 is a plan view of FIG.

FIG. 13 is a diagram showing a construction process of the underground water storage tank in the embodiment of the present invention.

FIG. 14 is a diagram showing a construction process of an underground water storage tank according to the embodiment of the present invention.

FIG. 15 is a diagram illustrating a construction process of an underground water storage tank according to the embodiment of the present invention.

FIG. 16 is a perspective view of the liner plate 1. FIG.

FIG. 17 is a plan view showing an example of assembling the liner plate 1.

FIG. 18 is a plan view showing an example of the assembled liner plate 1.

FIG. 19 is a view showing a conventional underground water storage tank construction process.

FIG. 20 is a view showing a construction process of a conventional underground water storage tank.

FIG. 21 is a diagram showing a conventional underground water storage tank construction process.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Liner plate as a segment which comprises a structure, 2 ... Assembling apparatus, 3 ... Assembly table, 5 ... Support leg,
Reference numeral 6 denotes a support, 7 denotes a spacer, 8 denotes a hanger as a lifting means, 10 denotes a storage tank structure as a structure, 22 denotes a shaft, 25
... Reinforcing mesh as reinforcement, 27. Base concrete as base, 29. Solidified material as filler.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Katsukuni Ashino 3-1-2 Takada, Chigasaki, Kanagawa (72) Inventor Hiroshi Shibuya 144-71, Kamesugada-cho, Hodogaya-ku, Yokohama, Kanagawa Prefecture (72) Inventor Mori Masato 7-36 Odajimacho, Shinjo City, Yamagata Prefecture (72) Inventor Fujio Seya 1-21-20 Izumigaoka, Iwaki-shi, Fukushima F-term (reference) 2D055 BB01 EB01 GB01 KB04

Claims (5)

[Claims] 1. A method for constructing a shaft comprising a step of excavating a shaft while applying mud pressure to a wall surface, a step of assembling a structure on the ground, and a step of installing and fixing the assembled structure in the shaft. 2. A step of excavating a shaft while applying muddy water pressure to a wall surface, a step of assembling a cylindrical structure having a smaller diameter than the shaft and having an open top and bottom, and a step of assembling the assembled structure and the inner surface of the shaft. Installing the structure in the shaft such that a gap is generated between the outer surface of the structure and the wall surface of the shaft, and discharging the mud while introducing a solidifying material into the bottom of the shaft. Fixing the structure in the shaft by means of a shaft. 3. The method according to claim 2, wherein a reinforcing material is fixed to an opening at a bottom of the structure, and a solidified material reinforces a base formed at a lower portion of the shaft. . 4. A method for assembling a tubular structure having an open top and bottom, which is installed in a shaft, comprising the steps of: dividing a segment divided in a circumferential direction and a height direction;
Forming a first stage by connecting circumferentially at an assembling position; lifting the first stage at a position higher than the height of the segment at the assembling position; and placing the segment under the first stage Connecting and circumferentially connecting to form a second stage. 5. An assembling apparatus for assembling a tubular structure having upper and lower openings by connecting segments divided in a circumferential direction and a height direction, wherein an assembling position of the segment is provided on an upper surface thereof. An assembling table having a working hole formed in the center to provide a working space; a support leg provided on a lower surface of the assembling table to support the assembling table at a predetermined height; A plurality of pillars erected on the upper surface of the assembling table at intervals in the circumferential direction, and having a height greater than the height of the segments, and being rotatable with respect to the supporting pillars on the assembling table. When the assembly is performed by connecting the segments in the circumferential direction at the assembly position, the segments are set at outer positions that do not intersect with the assembly position. When supporting a step composed of a plurality of the segments connected in the circumferential direction, a space connecting the segment of the next step to the lower surface of the step is set at an inner position crossing the assembly position. An assembly device for a structural body, comprising: a spacer to be formed; and a lifting means for lifting the segments connected on the assembly table.