JPH07189273A - Stabilizing structure of underground pressure-resistant structure - Google Patents

Abstract

PURPOSE:To hold the function of a pressure-resistant structure easily by stably bearing the underground pressure-resistant structure installed in the ground without depending upon the status of a bedrock on an outer circumference while preventing the generation of a crack, etc., by internal pressure. CONSTITUTION:Concrete rings reinforced by PC strands are sunk and mounted successively on the bottom of a shaft 16 excavated and formed by using various reverse circulation muddy water type pit excavators, etc., to construct a pressure-resistant structure 17 while muddy water having normal specific gravity in the shaft 16 is replaced with heavy muddy water 20, thus covering the periphery of the pressure-resistant structure 17 with heavy muddy water 20. The pressure-resistant structure 17 is stabilized by the heavy muddy water pressure of the filled heavy muddy water 20 while depth, in which the pressure-resistant structure 17 is installed, the excavation depth of the shaft 16, is reduced, thus allowing the mounting of the economical pressure-resistant structure 17. A barrier curtain 18 consisting of reinforced fibers such as carbon fibers, glass fibers, etc., is interposed between heavy muddy water 20 filled around the pressure-resistant strucure 17 and a bedrock on an outer circumference.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to stabilization of an underground pressure resistant structure for stabilizing an underground pressure resistant structure which is installed in the ground and stores a pressurized fluid such as a high pressure gas or a high pressure liquid. Regarding the structure.

[0002]

2. Description of the Related Art Pressure vessels such as various pressure tanks have been conventionally used as pressure resistant structures for storing pressurized fluids such as high-pressure gas and high-pressure liquid. In addition, especially in urban areas, in order to effectively use the ground surface of the area where these pressure resistant structures are installed and to improve the landscape,
Techniques for providing these pressure resistant structures in the ground have been proposed.

On the other hand, as an underground pressure resistant structure installed in the ground, a structure capable of withstanding higher pressure is demanded, and for example, CAES (Compressed Air) which is proposed to effectively use nighttime electric power. In the Energy Storage system, it is necessary to store high-pressure air of, for example, about 20 to 60 atm in an underground cavity formed by an underground pressure resistant structure.

The CAES system given as an example stores a high pressure gas, that is, high pressure air in an underground cavity by operating a compressor by night power, and uses the stored high pressure air during a daytime when power consumption is high. The turbine is operated to generate electricity. Further, according to this system, surplus power energy can be stored in urban areas without being returned to a pumped storage power plant such as a dam, so that efficient power use can be achieved.

[0005]

However, the above-mentioned C
An underground pressure-resistant structure installed in the ground represented by an underground cavity for storing high-pressure air in the AES system has a structure in which the internal pressure-resistant fluid is stored inside the underground pressure-resistant structure. Since the load toward the direction is applied, especially when the outer ground is loose, the earth pressure or water pressure to resist the outward load is not sufficient, so There is a problem that a large tensile stress is generated, which causes a crack or the like, which may make it impossible to stably maintain the function of the pressure resistant structure.

Further, due to the condition of the ground around the outer surface of the underground pressure-resistant structure, for example, non-uniformity, discontinuity, anisotropic deformation, anisotropic ground pressure, deformation of the ground due to long-term creep, etc. There is a problem that a biased load may be applied to the pressure-resistant structure, and therefore there is a risk that the pressure-resistant structure cannot be stably supported from the outside due to the outer peripheral ground.

Therefore, the present invention has been made in view of the above problems, and stably supports an underground pressure resistant structure installed in the ground without being influenced by the condition of the ground around the periphery. It is an object of the present invention to provide a stabilizing structure for an underground pressure resistant structure capable of preventing the occurrence of cracks and the like and easily retaining its function.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above object, and its gist is to provide an underground pressure resistance for storing a pressurized fluid such as high-pressure gas or high-pressure liquid installed in the ground. A stabilizing structure for an underground pressure-resistant structure for stabilizing a structure, comprising the heavy mud water filled to cover the outer periphery of the underground pressure-resistant structure, whereby the pressure-resistant structure is stabilized. It is in a structured structure.

Here, in the above description, the heavy mud water is defined as a liquid having a specific gravity which is approximately equal to or smaller than the unit volume weight of the surrounding ground, and is the temperature of the stored fluid in the room temperature or underground pressure resistant structure. It has physical properties based on the principle of Pascal as a fluid in a region, and is preferably composed of stable components that do not easily settle for a long period of time and does not rot, and specifically, for example, water, bentonite, a synthetic dispersant, and a heavy crystal. It is possible to use a mixture of fine stone powder and the like.

Further, in the present invention, it is preferable that a curtain member is interposed between the heavy mud water filled in the outer periphery of the underground pressure resistant structure and the outer peripheral ground.

Here, as the curtain member, carbon fiber,
A screen curtain reinforced with a reinforcing fiber such as glass fiber, a thin-walled iron pipe, or the like can be used, and further, for example, a waterproof sheet or the like used for tunnel lining can be used.

In the above description, the underground pressure resistant structure is composed of, for example, a fume concrete pipe, a prestressed concrete pipe, a precast concrete pipe, a composite pipe of iron pipe and concrete, and the like.

[0013]

According to the stabilizing structure of the present invention, the heavy mud water that covers the outer circumference of the underground pressure resistant structure and has a large specific gravity as compared with the groundwater. Thus, a large external pressure acts as a preload from the outer circumference of the underground pressure resistant structure, and a prestress for resisting the internal pressure of the fluid under pressure is applied in the cross section to reduce the tensile stress generated in the pressure resistant structure.

Further, this heavy mud is present between the pressure resistant structure and the outer peripheral rock, and pushes back the outer peripheral rock as a reaction force of the preload applied to the underground pressure resistant structure and supports the outer peripheral rock. Is given to prevent the loosening of the ground and restrain the outer peripheral ground near the initial ground pressure.

Further, due to its fluidity, this heavy mud water interferes with the effects of non-uniformity of ground, discontinuity, anisotropic deformation, anisotropic ground pressure, deformation of ground due to long-term creep, etc., The preload is evenly applied from the outer circumference of the underground pressure resistant structure without being affected by the condition of the outer ground.

Between the heavy mud water filled in the outer circumference of the underground pressure resistant structure and the outer ground, a barrier curtain reinforced with reinforcing fibers such as carbon fiber and glass fiber, or a curtain such as a thin-walled iron pipe. By interposing a member, it is possible to prevent heavy mud water from being interrupted from groundwater in the surrounding rocks for a long period of time to prevent water leakage and prevent heavy mud water from being lost.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 3 shows a first embodiment of the case where the stabilizing structure of the present invention is adopted in order to stabilize the pressure resistant structure for storing the high pressure air as the fluid to be pressurized in the CAES system. .

That is, this CAES system is a cylindrical pressure resistant structure constructed by using segments or cast-in-place concrete in a tunnel 11 excavated and formed in the ground 10 using a known technique such as a tunnel excavator. Structure 12 and underground space 2 provided near this pressure resistant structure 12
1 and a power generation system 13 including a compressor, a turbine power generator, and the like. And according to this CAES system, the high-pressure air generated by operating the compressor using night-time electric power is fed to the pressure-resistant structure 12 through the connecting pipe 14, and inside this, for example, about 20 to 60 atm. In the high pressure state, the stored high pressure air is taken out and the turbine in the power generation system 13 is operated to generate electric power during the daytime, so that the surplus electric power can be effectively used. it can.

The pressure resistant structure 12 for storing the high pressure air which constitutes the CAES system is stabilized by the heavy mud water 20 covering the outer circumference of the pressure resistant structure 12. That is, the tunnel 11 formed by excavation and formation
A tunnel shaft 15 that opens to the ground surface is in communication with the ground surface. By introducing heavy mud water 20 from the tunnel shaft 15, as shown in FIG. 4, the inner wall surface of the tunnel 11 and the pressure resistant structure 12 are separated. The gap between the outer surface and the outer surface is filled with the injected heavy mud water 20, and the heavy mud water 2 is further added.
By filling 0 to the upper part of the tunnel shaft 15, the heavy mud water 20 exerts a large heavy mud water pressure on the outer peripheral surface of the pressure resistant structure 12 by its pressure head.

Here, the heavy mud water 20 used in this embodiment
Is composed of, for example, the composition shown in Table 1,
Its specific gravity is about 2.00. Therefore, the pressure resistant structure 12 having the heavy mud water 20 filled in the periphery thereof is subjected to a preload on the outer peripheral surface by the large heavy mud water pressure, whereby prestress is introduced into the cross section of the pressure resistant structure 12.
That is, even if a high internal pressure is applied to the inner surface of the pressure resistant structure 12 by the high pressure air that is repeatedly stored, the tensile stress generated in the cross section due to this prestress is reduced. The heavy mud water 20 is used for the pressure resistant structure 12 and the tunnel 1.
As a reaction force of the above-mentioned pre-load which is interposed between the inner wall surface of No. 1 and the pressure resistant structure 12, the inner wall surface of the tunnel 11 which is loosened by excavation is pushed back and a supporting force is applied to the inner wall surface of The ground is restrained near the initial ground pressure, and due to its fluidity, the effects of ground non-uniformity, discontinuity, anisotropic deformation, anisotropic ground pressure, ground deformation due to long-term creep, etc. The preload is evenly applied from the outer periphery of the underground pressure resistant structure 12 without interfering with the condition of the outer peripheral ground.

[0021]

[Table 1] Further, FIG. 1 shows that the present invention is adopted to stabilize another type of underground pressure resistant structure used in the CAES system,
It is a schematic sectional drawing which shows a 2nd Example. That is, in this embodiment, for example, a concrete ring reinforced with PC strands is successively sunk and installed at the bottom of the vertical shaft 16 excavated and formed by using various types of reverse circulation mud type vertical hole excavators, etc. Is constructed and the mud having a normal specific gravity in the shaft 16 is replaced with the heavy mud 20, so that the pressure-resistant structure 17 is covered with the heavy mud 20. Also in this embodiment, the pressure-resistant structure 17 is stabilized by the action of the heavy mud water 20 similar to the above-described embodiment, and the pressure-resistant structure 17 is installed by the stabilization by using the heavy mud water 20. It is possible to reduce the depth, that is, the excavation depth of the vertical shaft 16 to enable economical installation of the pressure resistant structure 17. Further, in this embodiment, in particular, after the shielding curtain 18 made of reinforcing fibers such as carbon fiber and glass fiber is provided in the shaft 16 so as to cover the periphery of the pressure resistant structure 17, the barrier curtain 18 and the pressure resistant structure 17 are provided. The mud water in the vertical shaft 16 is replaced while injecting the heavy mud water 20 between it and the outer periphery of the shaft. That is, according to this method, when the mud is pushed out and the shaft 16 is filled with the heavy mud 20, as shown in FIG. 2, the shielding curtain 18 is provided between the heavy mud 20 and the outer peripheral ground 10. As a result, the heavy mud water 20 is shielded from the groundwater contained in the outer peripheral rock 10 for a long period of time, preventing the groundwater from leaking and preventing the heavy mud water 20 from being lost to the outer peripheral rock 10. In this embodiment, the pressure resistant structure 17 is firmly fixed to the bottom of the vertical shaft 16 by concrete or the like so as not to be lifted by buoyancy. The shield curtain 18 can also be used in the first embodiment.

In each of the above embodiments, CAE is used.
The case of applying the present invention to the underground pressure resistant structure for storing high pressure air in the S system has been described.
The stabilizing structure of the underground pressure resistant structure according to the present invention is not limited to the above-mentioned embodiment, and is not limited to the L. G. It can be adopted to stabilize any underground pressure-resistant structure for storing high-pressure gas such as P or other pressurized fluid such as high-pressure liquid.

[0023]

As described above, according to the stabilizing structure for an underground pressure resistant structure of the present invention, heavy mud water having a large specific gravity is filled around the underground pressure resistant structure. By the water pressure, without being affected by the situation of the surrounding rocks,
It is possible to stably support the underground pressure resistant structure installed in the ground, and to apply a prestress to resist the internal pressure of the pressurized fluid by exerting an external pressure from the outer circumference of the underground pressure resistant structure. By doing so, it is possible to reduce the tensile stress, prevent the occurrence of cracks, etc., and stably maintain the function of the underground pressure resistant structure. By interposing a screen curtain reinforced with reinforced fibers such as carbon fiber or glass fiber or a curtain member such as thin iron pipe between the mountain and the mountain, heavy mud water can be shielded from the groundwater in the surrounding rocks for a long time. Water leakage can be prevented and
It is possible to easily prevent heavy mud water from leaking to the outer ground.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a stabilizing structure of an underground pressure resistant structure according to an embodiment of the present invention, and illustrates a case where it is applied to a pressure resistant structure installed in a shaft.

2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is an explanatory view showing a stabilizing structure of an underground pressure resistant structure according to another embodiment of the present invention, and illustrates an example of application to a pressure resistant structure installed in a tunnel.

FIG. 4 is a cross-sectional view taken along the line BB of FIG.

[Explanation of symbols]

 10 Ground 11 Tunnel 12 Underground pressure resistant structure 16 Vertical shaft 18 Blocking screen 20 Heavy mud

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Yamashita 4-640 Shimoseido, Kiyose-shi, Tokyo Inside Obayashi Technical Research Institute Co., Ltd.

Claims (2)

[Claims] 1. A stabilization structure of an underground pressure resistant structure for stabilizing a underground pressure resistant structure which is installed in the ground and stores a pressurized fluid such as a high pressure gas or a high pressure liquid, comprising: A stabilizing structure for a pressure resistant structure comprising heavy mud water filled around the underground pressure resistant structure. 2. The underground pressure resistant structure according to claim 1, wherein a curtain member is interposed between the heavy mud water filled around the underground pressure resistant structure and the outer ground. Stabilized structure.