JPH0656078B2 - Underground dome construction method and device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method and an apparatus for constructing an underground dome.
More specifically, for example, a volume of several tens of thousands of meters in the underground
No. ³ underground dome construction method and apparatus therefor.

[Prior Art] Recently, a method of driving a generator with a gas turbine has been proposed as an auxiliary power generation system at the peak of daytime power consumption. This kind of gas turbine is 50-60kg / c
Although high pressure air of about m ² is required, it is unreasonable to manufacture such high pressure air using a compressor when the electric power is insufficient.

Therefore, it is considered that high-pressure air is manufactured by using late-night power that has surplus power and is low in cost, stored in a storage tank, and used at the peak of daytime power consumption.

When storing high-pressure air, a large city requires a storage volume of tens of thousands of m ³ per storage unit. Since it is practically difficult to install such a large-capacity storage tank in the suburbs of a large city, it is considered to store high-pressure air underground.

On the other hand, the conventional underground dome is intended for the construction of an underground power plant, etc., and most of them are constructed in a rocky area.

However, in large cities, it is rare to have a rocky area in the suburbs, and a new construction method for constructing the above-mentioned large-volume underground dome on relatively soft ground is necessary.

[Problems to be Solved by the Invention]

The present invention has been made focusing on such a problem, and its purpose is to efficiently construct a strong concrete underground dome without using reinforcing means or formwork even on relatively soft ground. Another object of the present invention is to provide an underground dome construction method and apparatus for constructing it without wastefully using ready-mixed concrete.

[Means for Solving the Problems]

The underground dome construction method of the present invention that can achieve the above-mentioned object, when constructing an underground dome having a larger diameter than the shaft in the lower part of the shaft, after forming a conical cavity in the ceiling part in the lower part of the shaft, Cone-shaped particles are raised in the cavity to form a conical void with the ceiling, and then concrete is poured into the conical void to form a concrete ceiling, Then, after removing the particulate matter in the cavity, each time a ring-shaped groove is formed immediately below the peripheral portion of the conical ceiling, fresh concrete is poured into the groove to form a ring-shaped concrete side wall. It is characterized in that the ring-shaped side wall is constructed in multiple stages downward.

Here, the shape of the ceiling is not particularly limited,
From the viewpoint of strength and easiness of construction method, it is desirable to make it a conical shape.

In addition, the angle of repose of particles such as sand or gravel deposited in a conical shape in the cavity is usually around 40 °, so the top inside angle of the conical ceiling may be around 40 °. desirable.

On the other hand, an underground dome construction device used when constructing an underground dome has a cylindrical main body that can be moved up and down in a vertical shaft, and a plurality of lateral excavation in a rotating body located in the middle of the main body. In an underground dome construction device in which arms are arranged to be openable and closable, a vertical shield machine is provided at the tip of the main body, and a tip drum cutter capable of moving in and out in the longitudinal direction is provided at the tip of the lateral excavation arm, and further, An excavating slag discharging means and a fresh concrete supplying means are provided on the main body and the lateral excavating arm, and further, a distance measuring arm is openably and closably disposed on the rotating body portion, and further, a distance along the distance measuring arm. It is characterized in that the meters are attached at predetermined intervals.

Here, the distance meter is not particularly limited, but since it is generally measured in turbid water, it is preferable to use an ultrasonic wave or an electromagnetic wave.

[Action]

Thus, after forming a cavity with a conical ceiling at the bottom of the shaft, a granular material is conically deposited in the cavity to form a conical void with the ceiling, and then , Each time a fresh concrete is poured into the conical void to form a concrete ceiling, and then, after removing particulate matter in the cavity, a ring-shaped groove is formed immediately below the peripheral portion of the conical ceiling. By pouring fresh concrete into it to form a ring-shaped concrete side wall and constructing this ring-shaped side wall in multiple stages downward, reinforcing means and formwork can be provided even on relatively soft ground. A strong underground dome made of concrete can be efficiently constructed without using it, and waste concrete can be used without waste.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but before that, an outline of an underground dome constructed by the method of the present invention will be described.

As shown in FIG. 2, this underground dome 1 is below the shaft 2 and is composed of a concrete ceiling 4 and a concrete side wall 6.

To illustrate the dimensions of each part, the shaft 2 has an inner diameter of 6 m and a depth of 500 to 600 m. On the other hand, both the inner diameter and the height of the underground dome 1 are 50 to 80 m. The concrete thickness is about 1 m. However, it goes without saying that these numerical values are for helping understanding of the scale of the underground dome 1 and are not limited to these dimensions.

The bottom of the underground dome 1 is formed in the process of forming the side wall 6, but when the bottom wall 10 made of concrete is formed,
This is the final step.

Next, the underground dome building device will be described with reference to FIG.

In FIG. 1, reference numeral 12 denotes an underground dome building device, which has a length reaching from the inside of the shaft 2 to the dome bottom (not shown). In this underground dome construction device 12, a main body 16 has a cylindrical shape, and an upper end portion thereof is a guide 1 attached to an upper portion of the main body.
It is held by 8 so as not to cause lateral shake.

Further, the main body 16 is provided with a vertical shield machine 20 at its lower end (tip). The vertical shield machine 20 is provided with a drum cutter 22 and a suction port (not shown) for cutting slag at the most distal end thereof.

The cutting slag is pumped to the ground as mud or slurry together with groundwater by a pump for pumping mud (not shown) provided in the main body 16. Generally, since the shaft 2 is filled with ground water to a considerably high position, the pump head of the pump does not need to be so high. Reference numeral 23 indicates the arrangement position of the pump chamber.

The main body 16 has a rotary body portion 24 at a predetermined position thereof, and the rotary body portion 24 has a pair of lateral excavation arms 26 and 2.
One end of 6 is supported by a shaft 28. In the present embodiment, the pair of lateral direction excavating arms 26, 26 are symmetrically supported with respect to the rotating body 24, while the pair of distance measuring arms 30, 30 are pivotally supported at a position having a 90 ° phase difference from them. is doing.

These arms 26, 30 are adapted to be opened and closed by pillars 32 like umbrella bones. That is, one end of the support column 32 (the support column 32 of the distance measuring arm 30 is not shown because it is hidden by the arm 30) is pivotally supported by the middle portion of the arms 26 and 30, and the other end is supported by the main body 16. Is pivotally supported by a guide (not shown) provided at the upper and lower sides, and the arms 26 and 30 are opened and closed with the shaft 28 as a fulcrum when the guide moves up and down along the main body 16.

The distance measuring arm 30 includes an ultrasonic distance measuring sensor 31.
Are attached at predetermined intervals. This sensor 31
In general, measurement is performed in turbid water, so that electromagnetic waves are preferable in addition to ultrasonic waves.

As a drive mechanism for opening and closing the arms 26 and 30, it is preferable to use a drive mechanism widely used in this type of device, for example, a hydraulic jack.

The lateral excavation arm 26 has traveling drum cutters 34, which can move along the arms 26, on both sides of the lateral excavation arm 26, and a tip drum cutter 36 capable of projecting a predetermined length at the tip thereof and discharge of a cutting slag and fresh concrete. It has an opening (not shown) for injection.

A supply pipe (tremy) 37 that also serves to supply fresh concrete, sand or gravel and a mud excavation sludge pipe 38 are provided in the cylindrical main body 16. These pipes 37, 38 are connected to a raw concrete supply pipe (not shown) and a slag discharge pipe (not shown) mounted in the lateral excavation arm 26 via a bent joint pipe and a switching valve (not shown).

In FIG. 1, reference numeral 40 is a wire for raising and lowering the main body, 41
Is a tremie hood made of iron (a narrow collar-shaped tubular body) having holes for allowing fresh concrete to uniformly flow out in the lateral direction, and 14 is the lower end of the shaft 2.

Next, a process of constructing an underground dome will be described with reference to FIGS. 3 to 7.

As shown in FIG. 3, the shaft 2 is constructed by the well-known open well Izutsu settlement method.

In the case of underwater excavation, the aqua header 42 or the reverse construction method is appropriately selected and used according to the depth.
Reference numeral 44 is a vertical shaft excavator that rotates around the shaft of the vertical shaft.

After constructing the vertical shaft 2, as shown in FIG. 4, the underground dome building device 12 is hung inside the vertical shaft 2 with the wire 40, and then the vertical shield machine 20 attached to the tip of the main body 16 is installed.
The drum body 22 of the main body 16 is driven by driving the drum cutter 22 of
Drill 4 until it comes out of shaft 2. The excavated slag is lifted together with mud water from the suction port provided at the tip of the vertical shield machine 20.

When the rotary body portion 24 of the main body 16 comes out of the vertical shaft 2, the rotation of the drum cutter 22 is stopped, and the lower end portion (tip portion) of the main body 16 is fixed to the ground 17. At this time, the upper portion of the main body 16 is supported in the vertical shaft 2 by the guide 18.

Next, the traveling drum cutter 3 provided on the lateral excavation arm 26
4 and the tip drum cutter 36 are driven, the rotary barrel 24 is rotated, and the lateral excavation arm 26 is further rotated by the shaft 28.
The ground 17 is excavated while the legs are opened at the fulcrum. The excavated slag is lifted from the opening at the tip of the lateral excavation arm 26.

When the lateral excavation arm 26 is opened to a predetermined angle, a tip drum cutter 36 provided at the tip of the lateral excavation arm 26 is projected forward to form a ring-shaped groove 45 having a predetermined depth.
The ring groove 45 becomes a portion that constitutes the side wall 6 of the underground dome 1.

By the excavation work described above, a cavity 46 having a conical ceiling portion and a spherical bottom portion is formed.

Next, the lateral excavation arm 26 is returned to the original position, and the distance measuring arm 30 is opened (not shown) to measure the excavation situation of the ceiling portion.

When the width (height) of the ring groove 45 is insufficient,
The work of widening the ring groove 45 may be performed again.

Next, as shown in FIG. 5, after the underground dome building device 12 is pulled up into the vertical shaft 2, sand or gravel is dropped from the excavated slag suction port provided at the tip of the underground dome building device 12 to deposit the deposited layer 48. To form. The deposition layer 48 leaves a cavity portion forming the ceiling 4 thereon and is deposited to a position where sand or gravel does not enter the ring groove 45.

Next, the hollow portion forming the ceiling 4 is filled with ready-mixed concrete from the tremie hood 41 for concrete supply. When this green concrete is solidified, the deposited layer 48 made of sand or gravel is sucked and discharged.

Then, again as shown in FIG.
After descending inward and excavating to a predetermined depth, the lateral excavating arm 26 is opened until the ceiling 4 is reached while excavating the natural ground. Next, while projecting the tip drum cutter 36, the ring groove 45 is formed similarly to the previous time. In that case, as shown in FIG. 7, it is preferable to grind the concrete of the ceiling 4 constructed previously to expose a clean concrete surface.

In addition, the uneven surface shown in FIG.
3 shows the cutting surface of the tip drum cutter 36. Further, reference numeral 52 is a pipe (tremy) which is provided in the lateral excavation arm 26 and serves both as supply of ready-mixed concrete and discharge of excavated slag.
Is.

Then, after returning the tip drum cutter 36 to the original position, while the lateral excavation arm 26 is rotated, the concrete is filled into the ring groove 45 from the opening hole (not shown) provided at the tip of the lateral excavation arm 26. To do. When this ready-mixed concrete is solidified, a side wall 6-1 having a ring-shaped section is constructed.

By repeating the above operation in sequence, the side walls 6-2, 6-3, ... Are successively constructed, and finally the side wall 6 is constructed, as shown in FIG.

Further, FIG. 8 shows a case where the bottom wall 10 is constructed. That is, when the underground dome building device 12 is used, a spherical excavation surface 54 is formed at the bottom of the cavity 46.

Therefore, the bottom wall 10 is formed by backfilling this part to some extent or by injecting fresh concrete without backfilling. When the ground is weak, the strength of the bottom can be increased in this way.

〔The invention's effect〕

As described above, according to the present invention, it is possible to efficiently use a solid underground dome made of concrete and waste ready-mixed concrete without using reinforcing means or formwork even in relatively soft ground. Can be built without.

[Brief description of drawings]

FIG. 1 is a schematic view of an underground dome building device according to the present invention, FIG. 2 is an explanatory view of an underground dome built by the method of the present invention, and FIGS. 3 to 8 use the underground dome building device according to the present invention. It is explanatory drawing which shows the procedure of constructing an underground dome. 16 ... Main body, 20 ... Vertical shield machine, 24 ... Rotating body, 26 ... Horizontal excavation arm, 30 ... Distance measuring arm, 3
1 ... Distance meter, 36 ... Tip drum cutter.

Claims (2)

[Claims] 1. When constructing an underground dome having a diameter larger than that of the vertical shaft at the lower part of the vertical shaft, a hollow having a conical ceiling is formed at the lower part of the vertical shaft, and then a granular material is conically bulged in the hollow. To form a conical void with the ceiling, and then to inject concrete into the conical void to form a concrete ceiling, and then remove particulate matter in the cavity. After that, each time a ring-shaped groove is formed immediately below the peripheral part of the conical ceiling, fresh concrete is poured into the groove to form a ring-shaped concrete side wall, and this ring-shaped side wall is directed downward. An underground dome construction method characterized by being constructed in multiple stages. 2. An underground dome construction device in which a tubular main body is vertically movable in a vertical shaft, and a plurality of lateral excavating arms are openably and closably arranged in a rotary body located at an intermediate portion of the main body. In addition, a vertical shield machine is provided at the tip of the main body, and a tip drum cutter that can move in and out in the longitudinal direction is provided at the tip of the lateral excavation arm. Means and a fresh concrete supply means are provided, and further, a distance measuring arm is openably and closably arranged on the rotating body portion, and further, distance meters are attached at predetermined intervals along the distance measuring arm. Underground dome construction device that does.