JPH1161859A - Construction method and structure for underground structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save the labor and time for the execution of apex concrete and largely shorten the whole construction period by precedingly constructing the most apex of the side wall of an underground structure to be connected to the apex inner face of an underground continuous wall. SOLUTION: After an underground continuous wall 1 is constructed, the most apex 5 of the side wall 4 of an underground structure such as an LNG tank 21 is precedingly constructed to be connected to the apex inner face of the underground continuous wall 1 via connecting members 22. A region surrounded by the underground continuous wall 1 is excavated, and the remaining portion of the side wall 4 except for a base plate and the most apex 5 of the side wall 4 is constructed in the excavated space. The crest of the remaining portion except for the most apex 5 of the side wall 4 is integrated with the lower end of the most apex 5. The labor and time for the execution of apex concrete can be omitted, the construction period can be largely shortened, and this method contributes to the provision of a stable foundation bed in the post process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and structure for constructing an underground structure, particularly an underground structure such as an LNG tank.

[0002]

2. Description of the Related Art Underground spaces are used for various purposes by taking advantage of underground characteristics such as constant temperature, airtightness, nonflammability, explosion proof properties, and high rigidity. Underground oil storage, LNG and LPG tanks, gas Active use of underground space is also being implemented or examined for energy facilities such as compressed air storage tanks for turbine power generation, superconducting coil power storage, and nuclear power plants.

In order to construct such an underground structure, for example, an LNG tank, first, as shown in an example of FIG. 7A, an annular underground continuous wall 1 is formed from a ground surface 9 which is a ground surface at the beginning of construction. Then, the interior space 2 surrounded by the underground continuous wall 1 is dug down while the underground continuous wall 1 is used as a retaining wall. After the bottom plate 3 is constructed on the bottom of the internal space, the side walls 4 are sequentially raised upward from the periphery of the bottom plate to a predetermined height (lot).
When the side wall is completed up to the top 5,
A roof 6 is hung over the top.

[0004] On the other hand, it is common practice to perform necessary facility work in parallel with or after the completion of the civil works, and finally to fill the embankment 8 to complete the LNG tank.

Here, when excavating the internal space 2 of the underground continuous wall 1, excavation-related heavy equipment such as a backhoe or a bulldozer is carried into the internal space, but it is necessary to carry out the excavated earth and sand to the ground. For example, it is necessary to install a lifting machine called Terha in the vicinity 9 of the ground surface of the underground continuous wall 1. Further, after the excavation work is completed, a crane for suspending a reinforced basket or a formwork, a mixer truck or a pump car for placing concrete in the formwork, to continuously construct the side wall 4 of the underground structure. Such heavy equipment must also be installed near the ground surface 9 of the underground continuous wall 1.

Therefore, before starting the excavation work,
As shown in (b), the head concrete 10 in the shape of a headband is wound around the top of the underground continuous wall 1.

According to the head concrete 10, the bending rigidity in the horizontal plane at the top of the underground continuous wall 1 is improved, so that a lifting machine (not shown) loaded on the vicinity 9 of the ground surface and other loads are firmly supported. While being able to
It will also provide a safe construction base.

[0008]

However, the construction process of such head concrete 10, which is performed between the construction process of the underground continuous wall 1 and the excavation process of the internal space 2, is as follows.
It is a so-called critical step in the whole process, and there has been a problem that about two to three months required for the construction of the head concrete leads to a delay in the whole construction period.

The present invention has been made in consideration of the above circumstances, and has as its object to provide a method and a structure of an underground structure capable of shortening the entire construction period by omitting the construction of head concrete. And

[0010]

According to a first aspect of the present invention, there is provided a method for constructing an underground structure, comprising: constructing an underground continuous wall; In the method of constructing an underground structure inside an underground structure, after constructing the underground continuous wall, interconnecting a topmost side wall of the underground structure to a top inner surface of the underground continuous wall. Pre-constructing the inner surface of the top in a form, excavating an area surrounded by the underground continuous wall, constructing a bottom plate and a sidewall remaining portion excluding the top of the sidewall in the excavated space, The top end is integrated with the lower end of the top of the side wall.

Further, in the method of constructing an underground structure according to the present invention, a roof lifting stand is constructed at the top of the side wall, and the roof assembled in the space before or during the construction of the remaining portion of the side wall is constructed. The roof is lifted using the roof lifting base, and the roof is hung over the top of the side wall.

In the construction structure of an underground structure according to the present invention, the underground structure is constructed inside the underground continuous wall along the inner surface of the underground continuous wall. In the construction structure of an underground structure, a top of a side wall of the underground structure and the underground continuous wall facing the top are interconnected.

In the construction method and structure of an underground structure according to the present invention, the underground continuous wall is first constructed, for example, in an annular shape, and then the top of the underground structure side wall is formed on the inner surface of the underground continuous wall. Build ahead. At this time, the construction is performed so that the top of the side wall is connected to the inner surface of the top of the underground continuous wall.

As described above, if the top of the side wall of the underground structure is preliminarily constructed in the form of a headband inside the top of the underground continuous wall by the reverse winding method before the excavation work, the head concrete can be conventionally removed. Without construction, it is possible to improve the bending rigidity in the horizontal plane at the top of the underground continuous wall,
A safe construction base in the post-process will be provided. Since the top of the side wall must be constructed as a part of the main body anyway, a period and materials necessary for constructing the head concrete can be directly saved.

Next, the inside area surrounded by the underground continuous wall is excavated, and then a bottom plate is constructed in the excavated space. Next, the remaining portion of the side wall excluding the top of the side wall from the peripheral edge of the bottom plate is constructed by a so-called forward winding method.

Next, the top of the remaining portion of the side wall is integrated with the lower end of the top of the side wall to complete the skeleton of the underground structure.

Here, a roof lifting frame is constructed at the top of the side wall, and the roof assembled in the space before or during the construction of the remaining side wall portion is lifted using the roof lifting frame, and the roof is mounted on the side wall. If it is bridged to the top, it is possible to carry out civil engineering work and equipment work of the internal space thereafter in all weather.

The roof may be assembled on the excavated ground before the construction of the bottom plate, may be performed on the bottom plate after the construction of the bottom plate, or may be performed at an arbitrary space position using an appropriate support. Is also good.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method and structure for constructing an underground structure according to the present invention will be described below with reference to the accompanying drawings. It is to be noted that the same reference numerals are given to components and the like that are substantially the same as those in the conventional technology, and description thereof will be omitted.

FIG. 1 is a partially enlarged view showing a construction structure of an underground structure according to this embodiment. As can be seen from the figure, in the construction structure of the present embodiment, an LNG tank 21 as an underground structure is constructed inside the underground continuous wall 1,
Of the side walls 4 constituting the LNG tank 21, the top 5 of the side wall and the top of the continuous underground wall 1 facing the top are connected to each other via a joining member 22.

FIG. 2 is a flowchart showing a procedure of a method of constructing an underground structure according to the present embodiment. As can be seen from the figure, in the construction method and structure of the underground structure according to the present embodiment, first, the annular underground continuous wall 1 is placed in FIG.
As shown in (a), construction is performed in the ground from the ground surface 9 (step 101). Here, when constructing the underground continuous wall 1, an embedded metal member 31 is embedded in the top inner surface in advance. Note that the center axis of the underground continuous wall 1 is on the left side in FIG.

Next, as shown in FIG. 2B, after the ground inside the underground continuous wall 1 is dug down appropriately to secure a work space 33, the LNG tank 21 is placed on the inner surface of the top of the underground continuous wall. The top of the side wall 5 is preliminarily constructed in an annular shape (step 102).
At this time, a stud bolt 32 is welded in advance to the embedded metal member 31 installed on the inner surface of the underground continuous wall 1 to form a joining member 22 together with the metal member. Then, the stud bolt 32 is fixed to the concrete frame at the top 5 of the side wall. In addition,
At the lower end of the side wall top 5, a vertical streak 34 is projected in advance downward.

Next, as shown in FIG.
The area enclosed by is excavated to form an internal space 2 (step 103), and then, as shown in FIG. 2B, bottom plates 41, 42, 43, and 44 are provided at the bottom in the excavated space 2. Construction is performed sequentially (step 104).

Next, as shown in FIG. 5 (a), the construction of the remaining side wall except the top portion 5 of the side wall 4 is performed in the third lot 51.
Starting from the bottom plate 43 by the winding method, the roof 6 is constructed on the bottom plate 44, and after the construction is completed, as shown by the arrow in FIG. The roof 6 is lifted up (step 105).

Next, the lifted roof 6 is shown in FIG.
(b) As shown in FIG.
A lot 52, a fifth lot 53, and so on are sequentially constructed (step 106).

At this stage, an opening 55 used for carrying in and out of the material 56 is provided in the roof 6. That is, the roof 6 functions as a roof that enables all-weather construction until the construction completion period. Therefore, it is desirable that the assembling and lift-up of the roof 6 be started immediately after the completion of the bottom plate construction, and that the construction of the remaining side wall be performed with the roof 6 spanned over the topmost portion 5.

Next, the top end of the last lot 56 in the remaining portion of the side wall is integrated with the lower end of the top portion 5 of the side wall as shown in FIG. 6 (step 107). That is, at the time of the concrete work of the rod 56, the vertical streaks 34 projecting from the lower end of the topmost portion 5 are fixed to the concrete body of the rod 56.

On the other hand, necessary equipment works such as cooling of the bottom plate, roof or side wall and membrane work and side heater work are performed in parallel with or after the civil work, and finally the embankment 8 is built. Then, the LNG tank 21 is completed.

As described above, according to the construction method and structure of the underground structure according to the present embodiment, L
Since the topmost portion 5 of the side wall of the NG tank 21 is precedently constructed in the form of a headband on the inside of the top of the underground continuous wall 1 by a reverse winding method, so that the underground continuous wall can be constructed without the need to construct the head concrete as in the related art. The bending rigidity in the horizontal plane at the top of the first part can be improved, and a safe construction base in a later process is provided.

Since the top portion 5 of the side wall must be constructed as a part of the side wall 4 of the main body anyway, the construction period of 2 to 3 months required for constructing the head concrete is required. Necessary materials can be omitted as it is.

In addition, according to the present embodiment, the roof 6 cannot be built until about one month has passed since the topmost portion 5 of the side wall 4 was constructed after the construction was completed. Since the top 5 is cured while the underground continuous wall 1 is being constructed, the construction period can be shortened by about one month.

According to this embodiment, the roof 6 constructed on the bottom plate 44 is lifted up by using the top 5 constructed at the beginning of the construction, and the lifted roof is moved to the top 5. Since the bridge is bridged, the remaining wall can be constructed in all weather.

In the present embodiment, the roof is lifted up by using the top constructed in advance, and the lifted roof is bridged over the top. However, instead of such a configuration, the conventional construction is adopted. The procedure, that is, the construction of the side wall may be completed, and then the bridge may be bridged to the top. In such a configuration, all-weather construction cannot be performed, but the same effect as described above can be obtained in that the labor for constructing the head concrete can be omitted and that there is no need to wait for curing at the top. it can.

In this embodiment, the explanation is made on the premise that the roof 6 to be lifted up is almost completed on the bottom plate 44 and connected to the top 5 only after the lift up. For example, if a delay in lift-up and a delay in the start of all-weather construction would lead to a light-weight temporary roof, a truss with a light-transmitting and water-blocking film on a temporarily assembled truss, for example, may be used. The light-weight temporary roof may be lifted up and fixed to the top portion 5 after assembling above.

According to this configuration, the temporary roof can be quickly assembled and lifted up, so that all-weather construction can be introduced at an early stage, and the temporary roof truss can be used as a foothold for the main roof construction. Since it can be performed in parallel with the side wall residual work, it is possible to further reduce the period of about eight months required for the roof concrete work and the subsequent waterproof work.

[0036]

As described above, according to the method of constructing an underground structure according to the first aspect of the present invention, before excavation work, the top of the side wall of the underground structure is continuously grounded by a reverse winding method. Since the head is pre-installed in the shape of a headband inside the top of the wall, it is possible to improve the bending rigidity in the horizontal plane at the top of the underground continuous wall without using the head concrete as in the past, and A safe construction base in the process will be provided.

Since the top of the side wall must be constructed as a part of the side wall of the main body anyway, it is necessary to construct the head concrete.
The construction period of up to three months and necessary materials can be omitted as it is.

Also, in the conventional case, if about one month has not passed as the curing period after the top of the side wall has been constructed,
Although the roof could not be built, according to this embodiment, since the top is cured while the underground continuous wall is being constructed, the construction period can be reduced by about one month here. it can.

According to the method of constructing an underground structure according to the second aspect of the present invention, the roof constructed on the bottom plate can be lifted up by using the top constructed earlier. On the side wall portion, there is an effect that construction can be performed in all weather.

Further, according to the construction structure of the underground structure of the present invention according to the third aspect, the side wall of the underground structure constructed in a state of being connected in a headband shape inside the top of the underground continuous wall. The top portion contributes to improving the bending rigidity in the horizontal plane at the top portion of the underground continuous wall before the excavation operation and providing a stable support base in a post-process.

Therefore, it is possible to save the labor for constructing the head concrete, shorten the construction period of two to three months, and if the curing time has elapsed since the top of the side wall was conventionally constructed. Otherwise, the roof could not be built, but according to the present invention, it is only necessary to cure the top portion while the underground continuous wall is being constructed. Can be achieved.

[0042]

[Brief description of the drawings]

FIG. 1 is a detailed longitudinal sectional view showing a construction structure of an underground structure according to an embodiment.

FIG. 2 is a flowchart showing a procedure of a method of constructing an underground structure according to the embodiment.

FIG. 3 is a diagram showing a state in which construction is being performed according to a procedure of a method of constructing an underground structure according to the present embodiment, and FIG.
FIG. 3B is a diagram illustrating a state in which an underground continuous wall is being constructed, and FIG. 3B is a diagram illustrating a state in which the top of an LNG tank, which is an underground structure, has been constructed in advance.

FIG. 4 is a view showing a state in which construction is being performed in accordance with a procedure of a method of constructing an underground structure according to the present embodiment, wherein (a) shows a state where internal excavation is completed, and (b) shows a state The figure which showed a mode that the bottom plate was constructed at the bottom of the internal space.

FIG. 5 is a view showing a state in which construction is being performed in accordance with a procedure of a method of constructing an underground structure according to the present embodiment. FIG. Lifted up the roof, (b)
Fixes the lifted roof to the top,
The figure which showed a mode that the construction of the side wall was progressing continuously.

FIG. 6 is an overall view of an LNG tank completed by a procedure of a method of constructing an underground structure according to the embodiment.

7A and 7B are diagrams showing a method and a structure of an underground structure according to the related art, wherein FIG. 7A is an overall view and FIG. 7B is a detailed view near the top.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Underground continuous wall 2 Internal space 4 Side wall 5 Top part (side wall) 6 Roof 21 LNG tank 22 Joining member 31 Embedded metal (joining member) 32 Stud bolt (joining member) 41-44 Bottom plate 51-56 lot (side wall)

Claims (3)

[Claims] 1. An underground structure construction method for constructing an underground continuous wall and constructing an underground structure inside the underground continuous wall, wherein the underground structure is constructed after the underground continuous wall is constructed. Preceding the inner surface of the underground continuous wall by interconnecting the top of the side wall of the object to the inner surface of the underground continuous wall, excavating an area surrounded by the underground continuous wall, and installing a bottom plate and a bottom plate in the excavated space. A method of constructing an underground structure, comprising: constructing a remaining portion of the side wall except for the top of the side wall, and integrating a top end of the remaining portion of the side wall with a lower end of the top of the side wall. 2. A roof lifting frame is constructed at the top of the side wall, and a roof assembled in the space before or during the construction of the remaining portion of the side wall is lifted using the roof lifting frame, and the roof is lifted. The method for constructing an underground structure according to claim 1, wherein the underground structure extends over the top of the sidewall. 3. A construction structure of an underground structure for constructing an underground structure inside an underground continuous wall along an inner surface of the underground continuous wall, wherein the underground structure includes: A construction structure of an underground structure, wherein the underground continuous wall facing the top is interconnected.