JP2583125B2 - Underground cavity construction method and equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method and an apparatus for constructing a large-scale spherical cavity underground at a large depth.

With the recent concentration of populations and institutions in urban areas and the emergence of land problems such as rising land prices, there has been a great deal of interest in the use of deep underground spaces in urban areas. In this deep underground space utilization concept, large-scale unsupported hollow spaces can be used for urban facilities such as sewage treatment facilities and municipal waste treatment facilities, and as storage facilities such as pressure tanks and water tanks. Has been raised. In particular, the spherical cavity is a shape that is more advantageous in strength against other pressures such as earth pressure and water pressure than other shapes (for example, Kamaboko type, bell shape, etc.), and has poor deep and ground conditions (low strength) Etc.) suitable for the shape of the cavity at the location.

[Conventional technology]

Conventional techniques for building the underground cavity (space) include a shield method, an open cut method, and a mountain method (such as a blasting method).

[Problems to be solved by the invention]

The structure of a large-scale hollow space in soft rock ground requires a structure surrounded by an outer wall that has strength and water resistance to withstand earth pressure and groundwater pressure in order to prevent collapse.

In the conventional mountain method, a concrete outer wall is constructed using a formwork and a support from the inside of the cavity created by excavation and earth removal. There was a risk of collapse in section (2), and there was a problem in ensuring safety. In addition, when there was infiltration of groundwater, work was difficult (or impossible).

In the excavation method, the surrounding area is closed off with a vertical wall from the surface of the ground using the underground continuous wall method, and the bottom and ceiling of the cavity are constructed using this wall as a retaining wall. In this case, it is necessary to excavate a large ground surface area larger than the projected area of the cavity, so that it cannot be constructed in a narrow place or where there is a structure. Furthermore, with the current construction method using a continuous underground wall, the bottom part cannot be closed because it is closed on a vertical wall. For this reason, there has been a problem that the construction cannot be performed if water from the bottom cannot be prevented.

The present invention has been made in consideration of the above, and it is possible to construct a large-scale spherical cavity, use only a small amount of land on the surface, can be applied under existing structures, and can be applied to soft rock ground. It is intended to provide a possible underground cavity construction method.

In addition, the above-mentioned spherical cavity can be constructed with a high-precision shape and dimensions, and it is possible to cope with a somewhat flat shape,
It is an object of the present invention to provide an underground cavity building apparatus that can be applied to a deeper depth.

[Means for solving the problem]

In order to achieve the above object, the underground cavity construction method according to the present invention is to construct a shaft from the ground, excavate a semi-circular groove radially from the shaft, and on the peripheral surface of the groove, upper and lower ends A curved spherical wall excavator connected to a pillar erected in a shaft is installed, and a curved groove excavation is performed by the spherical wall excavator. Concrete is poured into the inside to construct an outer peripheral wall for a unit longitude, and the following is repeated to close and form a spherical outer peripheral wall composed of a spherical underground continuous wall. Is excavated and discharged from the shaft to form a spherical underground cavity.

In addition, the underground cavity construction apparatus that implements the above-described underground cavity construction method is a curved rail that is rotatably supported at both ends on a column that is erected in a shaft, and that connects a number of bow-shaped rails in a freely bendable manner. An excavator that runs on one side of the curved rail and excavates the side opposite the one side of the curved rail, a front jack provided on the excavator traveling side of the curved rail, and a rear side provided on the other side of the curved rail It consists of a jack and a seal member provided on the outer peripheral surface of the arc shape of the curved rail.

[Action]

A spherical outer peripheral wall consisting of a continuous underground wall centered on a shaft is constructed. Then, the spherical outer peripheral wall is constructed for each unit longitude, and finally a spherical outer peripheral wall continuous with the side wall of the shaft is constructed.

In addition, the curved rail of the underground cavity building device is formed by bending each arched rail that constitutes it, making it straight, inserting it along the support from the shaft, and lowering it in the arc-shaped groove excavated in advance in the ground. The arcuate rails are sequentially expanded in an arc shape from the arcuate rails along the circumferential surface of the groove. Then, the excavator is mounted on the side of the curved rail. The curved rail is jacked forward by the amount of excavation by the excavator, and concrete is poured into the space behind the jack.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a conceptual view of the method of the present invention. First, a shaft 1 is constructed, a spherical outer peripheral wall 2 made of concrete is constructed below the shaft 1, and then a bedrock 3 inside the outer peripheral wall 2 is constructed. Cavities are excavated to complete the underground cavities. The excavated soil at this time is discharged from the shaft 1 to the ground. The shape of the outer peripheral wall 2 is not limited to a spherical shape, and other shapes such as a spheroid such as a rugby ball shape (FIG. 2) and a pumpkin shape (FIG. 3) as shown in FIGS. 2 and 3 are also conceivable.

The outer peripheral wall 2 is formed integrally with the intermediate portion of the shaft 1 and the side walls of the extended bottom 4 of the shaft 1 to form a shell as shown in FIG.

 Next, the procedure for applying the shell will be described with reference to FIG.

(1) Vertical shaft construction (Fig. 5) Underground cavity A where cylindrical underground continuous wall 5 is to be built
The shaft 1 is constructed by excavating inside the underground continuous wall. At this time, depending on the characteristics of the soft rock, a rock bolt / shot concrete method may be applied instead of the underground continuous wall. In the middle of the shaft 1, an enlarged diameter portion 1a is formed at a portion corresponding to the upper end of the underground cavity,
The bottom 4 is closed by a continuous wall.

(2) Grooving work (Fig. 6, Fig. 7, Fig. 8) A column 6 is erected in the shaft 1 and an excavator 7 for grooving is mounted on the column 6, and the enlarged diameter portion 1a of the shaft 1 is installed. And prepare for grooving excavation. As the excavator 7, a boom cutter type excavator is used as an example.

Next, an excavator 7 excavates an arc-shaped groove 8 whose inner peripheral surface is along the outer surface of the underground cavity A from both the enlarged diameter portion 1 a of the shaft 1 on both sides of the column 6. At this time, the excavator 7 extends its excavation arm as the excavation radius increases, and moves the excavator 7 down along the column 6.

After the excavation of the groove 8, the excavator 7 for grooving is pulled up, and the spherical wall excavator 9, 9 having a structure to be described later is inserted into each of the grooves 8, 8 in both grooves 8, 8.
Set along the inner peripheral surface of. Thereafter, the mortar 10 is filled in the grooves 8, 8 and the mortar 10 is closed. At this time, the space for the insertion portion of the spherical wall excavator 9 and the space of the shaft 1 are secured by using a mold or the like, and only the grooves 8, 8 are closed with the mortar 10.

(3) Construction of the outer peripheral wall (FIGS. 9 and 10) The slide cutter provided on the excavation surface side of the spherical wall excavator 9 excavates one unit longitude L of the spherical outer peripheral wall, and then excavates the excavation. Only the spherical wall excavator 9 is advanced in an arc shape around the column 6, and concrete 10 a is cast from the shaft 1 behind it.

The above operations are sequentially repeated to build the spherical outer peripheral wall 2 with concrete. At this time, since two spherical wall excavators 9 are used, each of them works over a range of 180 °.

(4) Excavation Work in Cavity (FIGS. 11 and 12) The excavator 7 is set in the shaft 1 again, and the rock inside the outer peripheral wall 2 constructed in the step (3) is excavated. At this time, the underground continuous wall 5 forming the hollow shaft 1 is cut, and excavation is performed while cutting and expanding the shaft 1. The excavated soil is slurried with muddy water and discharged. This excavation is performed with care so as not to damage the outer peripheral wall 2.

(5) Reinforcement work of outer peripheral wall When reinforcement of outer peripheral wall 2 is necessary, it is appropriately performed by driving in anchor bolts or the like.

When excavating the excavation space in each of the above works, muddy water mixed with bentonite is injected from the ground to fill the excavation space. As a result, each excavation space is backed up by the weight of the muddy water and is stabilized without collapsing, and the excavated earth and sand is discharged from the bottom 4 of the shaft 1 in a slurry state by a discharge pump.

Next, the configuration and operation of the spherical wall excavator 9 serving as a main excavator for performing the above-mentioned underground cavity construction method will be described in the following.
This will be described with reference to FIGS.

In the figure, reference numeral 11 denotes a curved rail formed by connecting a plurality of arcuate rails 11a, 11a... So as to be freely bent in an arc shape, and both ends of the curved rail are connected to upper and lower support rings 12a, 12b fitted to the column 6. ing.

The outer ends of each of the arcuate rails 11a are connected by hinges 13, and the inner ends of the arc-shaped rails 11a are hydraulic cylinders.
The arcuate rails 11a are connected to each other by extending the hydraulic cylinder 14 so that each of the arcuate rails 11a becomes substantially straight (the fourteenth rail).
(FIG. 15), and by shortening it, it becomes an arc shape (FIG. 15) along the inner periphery of the groove 8.

A rail 15 is provided in the longitudinal direction on the side surface on the excavation direction side of each bow-shaped rail 11a, and sealing grooves 16, 1 are provided on the inner and outer peripheral surfaces.
6 are formed. Further, a concave portion 17 is provided in a part of the rear side surface of the bow-shaped rail 11a, and a rear jack 18 is provided in the concave portion 17. The rear jack 18 pushes a foot 19 to the back side of the bow-shaped rail 11a, a pantograph-like link 20 connecting the bottom surface of the recess 17 and the foot 19, a screw rod 21 for expanding and contracting the link, and a motor for rotating this. It consists of 22. When the jack 18 is reduced, the concave portion 17 is closed by the foot 19. The bases of the links of the jack 18 are meshed and connected with each other by a gear, so that when the jack 18 is extended, the jack 18 projects backward without tilting downward.

On the side surface of the bow-shaped rail 11a on the digging side, a retractable front jack 23 is provided so as to be retractable.

A traveling platform 24 is engaged with the rail 15 of the bow-shaped rail 11a, and an excavator 25 is mounted on the traveling platform 24.

The traveling platform 24 has a traveling mechanism 26 for traveling on the curved rail 11, and a hydraulic drive device 27 for driving the traveling mechanism 26. An example of the traveling mechanism 26 includes a sliding mechanism (not shown in detail) which can mesh with the curved rail 11 and can move only along the rail via a slide shoe, and a driving mechanism using a hydraulic cylinder. The drive mechanism uses two hydraulic cylinders having a rail clamp at the tip, and these are alternately extended and contracted. This traveling mechanism may be replaced with a rack and a pinion.

The excavator 25 includes a boom 28 that can be extended and retracted and turned, and a rotary cutter drum 29 provided at a tip of the boom 28. The excavation width of this excavator 25 is a curve rail 10
It can be excavated with a width larger than the width in the inner and outer peripheral directions.

The seal grooves 16, 16 provided on the inner and outer peripheral surfaces of the curved rail 11 are filled with tube-type hydraulically expandable seal members 30, 30 which can be extended and contacted to the inner surface of the excavation width H. . The seal member 30 is in the form of a flexible bag string, and is expanded by injecting a liquid into the inside.

Next, the excavating operation of the spherical wall excavator 9 having the above configuration will be described.

With the shaft 1 and grooving work completed, the curved rail
11, supporting rings 12a, 12b each having both ends fitted to the column 6.
And inserted into the shaft 1 (Fig. 13).

Then, with the curved rail 11 facing the groove 8, the hydraulic cylinders 14 provided therebetween are shortened and moved in order from the lower bow-shaped rail 11 a into the arc 8 in the groove 8 sequentially. . The curved rail 11 is fixed along the inner peripheral surface of the groove 8 with the uppermost hydraulic cylinder 14 shortened.

The relationship between the groove 8 and the size of the curved rail 11 is as shown in FIG.

That is, for example, the width W _{1 in} the excavation direction of the curved rail 11 is 1 m
Then, the width W of the groove 8 is equal to the space for the excavator 25 and the slurry.
₃ to 3.2 m is required including W2.

The curved rail 11 in the groove 8 is moved to the rear end side in the digging direction by the action of the front jack 23 as shown in FIG.

In this state, a mortar 10 is cast on a part of the groove 8 except for the rail insertion part and the shaft part 1 and the mortar 10 is closed. At this time, the template 3
Insert 1,32 to prevent mortar 10 from flowing into them.

In this state, the lower end of the curved rail 11 faces the bottom 4 of the shaft 1, and the upper end thereof faces the enlarged diameter portion 1a of the shaft 1.

Next, a traveling platform 24 equipped with an excavator 25 is engaged with the rail 15 on the excavation side of the curved rail 11 from the enlarged portion 1a of the shaft 1 to start, and excavates downward toward the lower portion of the shaft 1. . Assuming that the excavation allowance at this time is 1 unit longitude, this 1 unit longitude L is, for example, as shown in FIG.
When a 50m, first D ₁ drilling portion of the vertical shaft 1 of the upper (North Pole) is 0.9 m, an intermediate section (equator) of the drilling the D ₂ is 3.2 m, the lower drilling cost of the vertical shaft 1 part of (Antarctica) D ₃ is 0.6 m, the 25
As shown in the figure, it becomes a groove like a vertically cut melon skin. This is excavated so that the boom 28 of the excavator 25 has a predetermined shape by the vertical and horizontal rotation and expansion / contraction operations and the traveling operation.

The excavated earth and sand at this time falls in the space (2 m × 2 m) between the curved rail 11 and the ground, collects at the bottom 4 of the shaft 1, and is discharged to the ground by a slurry pump or an air lift.

After completion of the excavation of the wall groove by one unit longitude L as described above, as shown in FIG. 23, the rear jack 18 of each of the arcuate rails 11a, 11a of the curved rail 11 is moved to FIG. 17 (A). By operating as shown, each foot 19 is pulled, and the curved rail 11 is pushed forward in the excavation direction by the above-mentioned one unit longitude L.
At this time, the front jack 23 on the digging side is held forward with a predetermined length (W ₂ ), and the excavator 25 and the space W ₂ for slurry are secured on the front side of the curved rail 10 in the digging direction. To

Next, concrete is poured into the space formed behind the curved rail 11 to form a part of the underground continuous wall.

At this time, since the concrete is filled from the lower side, prior to this, it is sequentially stored from the lower rear jack 18 and the rear jack 18 is closed with the foot 19, and concrete does not enter into this. At the same time, the back of the curved rail 11 closed by the foot 19 is used as a concrete end form.

In a series of operations from the excavation to the movement of the curved rail 11 to the concrete placement, a continuous wall segment of one unit longitude is created, and this is repeated to construct a spherical continuous underground wall. FIG. 24 shows this work viewed from above. In this figure, B indicates the projected shape of the excavation part for the unit longitude.

In the above operation, the step of closing the groove 8 with mortar may be closed with concrete together with the space for the first unit longitude. In this case, a mold for closing the curved rail insertion portion is not required.

In the above operation, when concrete is cast on the back side of the curved rail 11, the outer peripheral surface of the curved rail 11 is sealed by the seal members 30, 30 provided in this portion.

The seal at the lower part of the curved rail 11 is the seal member
Using a backing plate provided with a tube-type hydraulic inflatable sealing member similar to 30, the backing plate is pressed against the gap from the inside of the shaft 1 and sealed.

〔The invention's effect〕

According to the underground cavity construction method of the present invention, it is possible to construct a large-scale spherical cavity that is advantageous in strength against earth pressure and water pressure. In addition, since all construction can be performed from the shaft 1 having a small diameter, an underground cavity can be built in a narrow place or under an existing structure. In addition, before the internal excavation and earth removal, the outer peripheral wall consisting of a spherical and completely closed continuous wall will be constructed, so that a large-scale underground cavity will be built without risk of collapse even in the weak areas of urban areas. be able to.

Although it is necessary to pump groundwater where there is flooding, according to the method of the present invention, as described above, internal excavation is performed while the deadline is completely closed, so groundwater is not moved, and groundwater is pumped. There is no danger of land subsidence due to.

Furthermore, according to the construction method of the present invention, since it is possible to excavate in a rotating body shape centering on the shaft 1, it is possible to construct a line-symmetric spherical outer peripheral wall centering on the shaft without using any special control means.

According to the apparatus of the present invention for performing the above-mentioned underground cavity construction method, the above-described method of the present invention can be efficiently performed. In particular, according to the underground cavity building apparatus according to the present invention, the outer peripheral wall 2 has a curved rail with the shaft 1 as an axis.
Since the drill can be excavated into a rotating body that can be formed by rotating 11, a spherical outer peripheral wall having a precise shape and dimensions can be constructed. Further, by being a rotating body, it is possible to cope with a somewhat flat shape by changing the shape of the curved rail 11. Furthermore, it can be applied to deep depths by achieving unmanned operation.

[Brief description of the drawings]

The drawings show an embodiment of the present invention.
FIG. 3 is a conceptual diagram of the method of the present invention, and FIG. 4 is a sectional view of an underground continuous wall. FIGS. 5 to 12 illustrate the steps of the method of the present invention. FIG. 5 is a sectional view of a shaft, FIG. 6 is an explanatory view of a trench cutting work, and FIG. FIG. 8 is a sectional view taken along the line A, FIG. 8 is a perspective view showing a schematic shape of a shaft and a groove,
FIG. 9 is an explanatory view of the work of the outer peripheral wall construction, and FIG. 10 is B in FIG.
FIG. 11 is a sectional view taken along the line B-B, FIG. 11 is an explanatory view of the work of excavating work in the cavity, and FIG. 12 is a sectional view taken along the line CC of FIG.
13 to 20 show the configuration of the device of the present invention.
FIG. 13 is an explanatory view showing the entire configuration of the spherical wall excavator and how it enters into the groove, FIG. 14 and FIG. 15 are side views showing the configuration and operation of the spherical wall excavator, and FIG. Sectional view of the bow-shaped rail, FIG. 17 is a sectional view of the bow-shaped rail, FIG. 17 (A) is an explanatory view of the operation of the rear jack, and FIG. 18 to FIG. Side view, plan view, front view,
FIG. 21 is a cross-sectional view showing the relationship between a curved rail and a groove of a spherical wall excavator, FIG. 22 is an excavation procedure diagram, FIG. 23 is a rail support holding procedure diagram, FIG. 24 is a plan view showing an excavation procedure, FIG. 25 is a perspective view showing an excavation allowance for a unit longitude. 1 is a shaft, 2 is an outer peripheral wall, 8 is a groove, 9 is a spherical wall excavator, 11
Is a curved rail, 11a is an arcuate rail, 18 is a rear jack, 2
3 is a front jack, 25 is an excavator, and 30 is a sealing member.

 ──────────────────────────────────────────────────続 き Continued on the front page (73) Patent holder 999999999 Taisei Corporation 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo (73) Patent holder 999999999 Central Research Institute of Electric Power Industry 1 Otemachi, Chiyoda-ku, Tokyo ―6-1 (73) Patent Holder 999999999 Hitachi Construction Machinery Co., Ltd. 2-6-1 Otemachi, Chiyoda-ku, Tokyo (73) Patent Holder 999999999 Fujita Co., Ltd. 4-6-115 Sendagaya, Shibuya-ku, Tokyo ( 73) Patent holder 999999999 Komatsu Manufacturing Co., Ltd. 2-3-6 Akasaka, Minato-ku, Tokyo (72) Inventor Masao Hayashi 131-7 Wakamatsu, Abiko-shi, Chiba (72) Inventor Yoshitane Ishino Manda, Hiratsuka-shi, Kanagawa 1200 Komatsu Ltd. Laboratory (72) Inventor Kiyotake Mori 340-15 Iwasawa, Hanno City, Saitama Prefecture (56) References JP-A-2-157399 (JP, A) JP-A-1- 230894 (JP, A) JP-A-2-108798 (JP, A)

Claims (2)

(57) [Claims] 1. A shaft 1 is constructed from the ground, and a semicircular groove 8 is excavated radially from the shaft 1, and on the peripheral surface of the groove 8, both upper and lower ends are supported by a column 6 standing upright in the shaft. The connected curved spherical wall excavator 9 is installed, a curved groove excavation is performed by the spherical wall excavator 9, and thereafter, the vehicle is advanced by the amount of the excavation, and concrete is poured into the space on the rear side of the excavator. Then, the outer peripheral wall for the unit longitude is constructed, and thereafter, the above operation is repeated to close the outer peripheral wall, thereby constructing a spherical outer peripheral wall 2 composed of a spherical underground continuous wall, and then excavating the rock inside the outer peripheral wall 2. ,
This is discharged from the shaft 1 to construct a spherical underground cavity. 2. A curved rail 11 in which both ends are rotatably supported by a column 6 erected in a shaft 1 and a number of bow-shaped rails 11a are connected to bend freely, and one side of the curved rail 11 runs. An excavator 25 that excavates the opposite side of the curved rail 11 from one side, a front jack 23 provided on the excavator traveling side of the curved rail 11, and a rear jack 18 provided on the other side of the curved rail. And a sealing member 30 provided on the outer peripheral surface of the arc shape of the curved rail 11.