JP2009299292A - Shear transmission structure between sidewall of underground tank and continuous underground wall - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce cost by simplifying a structure. <P>SOLUTION: This shear transmission structure 10 between a sidewall 3 of an underground tank 1 and a continuous underground wall 2 constructed in the ground is constructed by embedding a slip bar 11 over both of the sidewall 3 of the underground tank 1 and the continuous underground wall 2, integrally fixing a continuous underground wall side embedded part 11a of the slip bar 11 to the continuous underground wall 2, and providing a buffer material 12 on the sidewall side embedded part 11b of the slip bar 11. The weight of the underground tank 1 is not transmitted to the continuous underground wall 2, but only the buoyancy applied to the underground tank 1 is transmitted to the continuous underground wall 2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shear transmission structure between a side wall and a continuous underground wall in an underground tank used for LNG storage or the like.

Conventionally, for example, an underground tank used for LNG storage is constructed in a state of being buried in the ground, and receives buoyancy due to the water pressure of the underground water. Therefore, for example, Patent Document 1 discloses a technique in which a water drainage structure is provided near the bottom of the underground tank so that the pumping pressure does not act on the underground tank in order to prevent the floating of the underground tank due to this buoyancy. ing.
Patent Document 1 describes a structure in which groundwater submerged inside the underground continuous wall is collected in a crushed stone layer provided in the lower part of the underground tank and further drained to the ground with a pump.

Further, for example, Patent Document 2 proposes a structure that prevents floating in an underground tank that takes an operation mode without draining water.
Patent Document 2 discloses a structure in which a slip bar is inserted between a side wall of an underground tank and a continuous underground wall, and the continuous underground wall and the side wall are integrated, and is open to the side wall side of the continuous underground wall. Saddle pipe is buried, one end of the slip bar is inserted into the sheath pipe and fixed with filling hardened material, and the other end is buried in the side wall, so that the underground tank is connected to the continuous underground wall in the axial direction of the slip bar Describes a structure that can be displaced freely and prevents the underground tank from floating by adding the weight of the underground continuous wall.
Japanese Patent Laid-Open No. 9-2572 JP-A-9-268582

  By the way, underground tanks usually have drainage facilities, and after tank completion, both when draining operation and when draining operation is not performed (when draining operation is interrupted due to an earthquake, etc.) Designed to be able to. Therefore, when a slip bar is provided between the side wall and the continuous underground wall, if the body weight of the tank itself is large, the slip bar should be installed so that it can withstand both buoyancy and the body weight of the tank itself. There is a problem that the number increases or the diameter increases, which increases the cost.

  The present invention has been made in view of the above-described problems, and provides a shear transmission structure between a side wall and a continuous underground wall in an underground tank that can reduce costs by adopting a simple structure. With the goal.

  In order to achieve the above object, in the shear transmission structure between the side wall and the continuous underground wall in the underground tank according to the present invention, the side wall in the underground tank having the side wall and the bottom plate inside the continuous underground wall constructed in the ground, A shear transmission structure with a continuous underground wall, characterized in that a steel bar is embedded over both the continuous underground wall and the side wall, and a buffer material is provided on the side wall side embedded part of the steel bar. Yes.

In the present invention, when an upward force is applied to the underground tank by receiving the pumping pressure that acts upward in the vertical direction due to the water pressure of the groundwater, a force to lift the underground tank is applied. The upward movement of the underground tank is restricted in a state in which is in contact with the buried portion on the side wall side of the steel rod having the shear transmission structure. That is, the upward force applied to the side wall is transmitted to the continuous underground wall through the steel bar. Therefore, the weight obtained by adding the weight of the continuous underground wall to the weight of the tank itself provides resistance to the buoyancy acting on the underground tank that has been subjected to the pumping pressure (upward force to lift), and the underground tank is lifted Can be suppressed.
Moreover, since the buffer material is provided on the side wall side buried part of the steel bar, downward force such as the weight of the underground tank does not act on the steel bar, and the downward force is applied via the steel bar. It will not be transmitted to the continuous underground wall. Therefore, it is sufficient that the steel rod has a proof strength corresponding only to the upward buoyancy acting on the underground tank. For example, a shear transmission structure with reduced specifications such as the number and diameter of the steel rod can be provided. .

  Further, in the shear transmission structure between the side wall and the continuous underground wall in the underground tank according to the present invention, the side wall and the continuous underground wall in the underground tank having the side wall and the bottom plate inside the continuous underground wall constructed in the ground. In this shear transmission structure, a steel bar is embedded over both the continuous underground wall and the side wall, and a buffer material is provided under the continuous underground wall side embedded part of the steel bar.

In the present invention, when an upward force is applied to the underground tank by receiving a pumping pressure that acts upward in the vertical direction due to the water pressure of the groundwater, a steel rod integrated on the side wall is applied with a force to lift the underground tank. The upward force will also be applied. At this time, the upward movement of the underground tank is restricted in a state in which the continuous underground wall side buried portion of the steel bar is in contact with the upper part of the inner surface of the insertion hole of the continuous underground wall. That is, the upward force applied to the side wall is transmitted to the continuous underground wall through the steel bar. Therefore, the weight obtained by adding the weight of the continuous underground wall to the weight of the tank itself provides resistance to the buoyancy acting on the underground tank that has been subjected to the pumping pressure (upward force to lift), and the underground tank is lifted Can be suppressed.
In addition, since the buffer material is provided under the continuous underground wall side buried part of the steel bar, downward force such as the weight of the underground tank does not act on the steel bar, and the downward force is It is no longer transmitted to the continuous underground wall via Therefore, it is sufficient that the steel rod has a proof strength corresponding only to the upward buoyancy acting on the underground tank. For example, a shear transmission structure with reduced specifications such as the number and diameter of the steel rod can be provided. .

  According to the shear transmission structure between the side wall and the continuous underground wall in the underground tank of the present invention, the buoyancy (upward force) applied to the underground tank without transmitting the weight (downward force) of the underground tank to the continuous underground wall. ) Can be transmitted to the continuous underground wall, it is possible to reduce the proof stress of the steel rod and to reduce costs such as member costs.

Hereinafter, a shear transmission structure between a side wall and a continuous underground wall in an underground tank according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
1 is a longitudinal sectional view showing a schematic configuration of a shear transmission structure of an underground tank according to a first embodiment of the present invention, FIG. 2 is an enlarged view of a main part of the shear transmission structure shown in FIG. 1, and FIG. It is an AA line sectional view shown.

  Reference numeral 1 in FIG. 1 indicates an underground tank according to the first embodiment constructed in the ground G. The underground tank 1 is used, for example, as an LNG storage tank, is reinforced concrete, is formed in a bottomed cylindrical shape along the inner periphery of a continuous underground wall 2 having a cylindrical wall shape, and a side wall 3 and a bottom plate 4.

  The continuous underground wall 2 is constructed in the ground deeper than the bottom plate 4 of the underground tank 1 for the purpose of preventing the collapse of the ground as a soil retaining and a water stopping function. It is constructed by a well-known technique in which an excavation groove is provided along and concrete is poured into the groove. The edge between the continuous underground wall 2 and the side wall 3 of the underground tank 1 provided on the inner peripheral side thereof is cut by an edge cutting material S such as a vinyl sheet and is not fixed to each other (FIG. 2). reference).

A plurality of shear transmission structures 10, 10,... Are interposed between the continuous underground wall 2 and the side wall 3 of the underground tank 1, and the underground tank 1 is connected by the shear transmission structures 10, 10,. And the continuous underground wall 2 are connected to each other. These shear transmission structures 10, 10,... Are arranged in a large number at predetermined intervals along the vertical direction and circumferential direction of the underground tank 1.
In addition, about the edge cut | disconnection of the continuous underground wall 2 and the side wall 3, depending on how the concrete grounding process of the continuous underground wall 2 side with respect to the side wall 3 is carried out, even if it does not interpose the edge cutting material S, it will be in a substantially edge-cut state. There is a case.

  As shown in FIGS. 2 and 3, the shear transmission structure 10 includes a slip bar 11 (steel bar) embedded over both the continuous underground wall 2 and the side wall 3, and a side wall-side embedded portion 11 b of the slip bar 11. It is the structure provided with the shock absorbing material 12 provided only on the top.

The slip bar 11 is, for example, a round steel bar having an outer diameter D1 (see FIG. 3) of 38 mm, and one end (continuous underground wall side embedded portion 11a, right side toward the paper surface in FIG. 2) is continuous underground. It is embedded in the wall 2 and the other end (side wall side embedded portion 11 b, also on the left side as viewed in the drawing) is embedded in the side wall 3 of the underground tank 1.
The continuous underground wall 2 and the continuous underground wall side buried portion 11a of the slip bar 11 are fixed in a cured state by filling a gap between them with a curing material 13 such as epoxy resin or mortar. And the insertion hole 2A for inserting the continuous underground wall side burying portion 11a formed in the continuous underground wall 2 has a cross-sectional shape capable of filling an appropriate amount of the hardening material 13 around the slip bar 11. Yes.

  The buffer material 12 is made of, for example, a material such as styrene foam, and is provided so as to rise on the side wall-side embedded portion 11 b of the slip bar 11. The installation range of the buffer material 12 is, for example, a range of about 30 mm in the height D2 from the upper end of the slip bar 11 having an outer diameter D1 (see FIG. 3) of 38 mm.

Then, with the cushioning material 12 circumscribed on the slip bar 11, the outer periphery of the slip bar 11 is covered with an insulating tape 14 (insulating member) and buried, so that the slip bar 11 extends along the axial direction E inside the side wall 3. And is free to move.
That is, since the slip bar 11 is integrated with the continuous underground wall 2 and is separated from the side wall 3, the underground tank 1 (side wall 3) is in contact with the continuous underground wall 2. And is not restrained in the horizontal direction.

Next, the effect | action of the shear transmission structure 10 provided in the underground tank 1 mentioned above is demonstrated based on drawing.
As shown in FIGS. 1 and 2, according to the shear transmission structure 10 according to the first embodiment, the boundary surface between the continuous underground wall 2 and the side wall 3 is not joined. Furthermore, the continuous underground wall side buried portion 11a of the slip bar 11 is integrally fixed to the continuous underground wall 2, and the sidewall side buried portion 11b is movable in the axial direction E with respect to the sidewall 3, Even when the side wall 3 of the underground tank 1 undergoes temperature shrinkage or during an earthquake, the side wall 3 can be displaced without being restrained in a direction away from the continuous underground wall 2. Generation of cracks can be prevented.

  In addition, when an upward force F1 is applied to the underground tank 1 due to the pumping pressure that acts upward in the vertical direction due to the water pressure of the groundwater, a force to lift the underground tank 1 is applied, but the slip of the shear transmission structure 10 is applied. Since the lower side of the side wall embedded portion 11b of the bar 11 is in contact with the side wall 3, the upward movement of the underground tank 1 is restricted. That is, the upward force F <b> 1 applied to the side wall 3 is transmitted to the continuous underground wall 2 through the slip bar 11. Therefore, the weight obtained by adding the weight of the continuous underground wall 2 to the weight of the tank itself is a proof force against the buoyancy acting on the underground tank 1 subjected to the pumping pressure (upward force F1 to lift) The lift of the tank 1 can be suppressed.

  Further, since the cushioning material 12 is provided on the side wall buried portion 11b of the slip bar 11, the downward force F2 such as the weight of the underground tank 1 does not act on the slip bar 11, and the downward force F2 thereof. Is not transmitted to the continuous underground wall 2 via the slip bar 11. Therefore, the slip bar 11 only needs to have a yield strength corresponding to only upward buoyancy acting on the underground tank 1, and for example, a shear transmission structure with reduced specifications such as the number and diameter of the steel bars is adopted. Can do.

  As described above, in the shear transmission structure between the side wall and the continuous underground wall in the underground tank according to the first embodiment, the weight (downward force F2) of the underground tank 1 is not transmitted to the continuous underground wall 2. Since only the buoyancy (upward force F1) applied to the underground tank 1 can be transmitted to the continuous underground wall 2, the proof stress of the slip bar 11 can be reduced, and the costs such as the member costs can be reduced. be able to.

Next, other embodiments will be described with reference to the accompanying drawings. However, the same or similar members and parts as those of the above-described first embodiment are denoted by the same reference numerals, and description thereof is omitted. A configuration different from the embodiment will be described.
4 is a longitudinal sectional view showing the structure of the shear transmission structure according to the second embodiment, which corresponds to FIG. 2, and FIG. 5 is a sectional view taken along line BB in FIG.
As shown in FIGS. 4 and 5, the shear transmission structure 20 according to the second embodiment has a structure in which a buffer material 22 is provided on the continuous underground wall 2 side. That is, the side wall-side embedded portion 21 b of the slip bar 21 is embedded and fixed in the side wall 3.

  The cushioning material 22 is provided under the continuous underground wall burying portion 21a of the slip bar 21, and is made of, for example, a material such as polystyrene foam, and is provided so as to circumscribe the continuous underground wall side embedded portion 21a of the slip bar 21. It has been. And the insertion hole 2B formed in the continuous underground wall 2 for inserting the continuous underground wall side burying part 21a of the slip bar 21 has a cross-sectional shape capable of disposing the slip bar 21 and the cushioning material 22 thereunder. It has become.

  In the second embodiment, when an upward force is applied to the underground tank 1 due to the pumping pressure that acts upward in the vertical direction due to the water pressure of the groundwater, a force to lift the underground tank 1 is applied to the side wall. The upward force F <b> 1 is also applied to the slip bar 21 integrated with 3. At this time, the upward movement of the underground tank 1 is restricted in a state where the continuous underground wall side buried portion 21b of the slip bar 21 is in contact with the inner surface upper portion 2a of the insertion hole 2B of the continuous underground wall 2. That is, the upward force F <b> 1 applied to the side wall 3 is transmitted to the continuous underground wall 2 through the slip bar 21. Therefore, the weight obtained by adding the weight of the continuous underground wall 2 to the weight of the tank itself is a proof force against the buoyancy acting on the underground tank 1 subjected to the pumping pressure (upward force F1 to lift) The lift of the tank 1 can be suppressed.

  Moreover, since the buffer material 22 is provided under the continuous underground wall side buried part 21a of the slip bar 21, the downward force F2 such as the weight of the underground tank 1 does not act on the slip bar 21, and the downward direction Is not transmitted to the continuous underground wall 2 via the slip bar 21. Therefore, the slip bar 21 only needs to have a yield strength corresponding to only upward buoyancy acting on the underground tank 1, and for example, a shear transmission structure with reduced specifications such as the number and diameter of the slip bar 21 is adopted. be able to.

As mentioned above, although embodiment of the shear transmission structure of the side wall and continuous underground wall in the underground tank by this invention was described, this invention is not limited to said embodiment, The range which does not deviate from the meaning It can be changed as appropriate.
For example, the configuration, such as the position, quantity, diameter dimension, and axial length dimension of the slip bars 11 and 21 (steel bars) can be arbitrarily selected according to conditions such as the size, weight, pumping pressure, etc. of the underground tank 1. Can be set.

Further, although the insulating tape 14 is employed in the present embodiment, a member such as a resin sheath such as soft vinyl chloride or a tube (cap) may be covered.
Furthermore, the installation range and the installation amount of the buffer materials 12 and 22 are not limited to the present embodiment. For example, in the present embodiment, the continuous underground wall side buried portion of the slip bar, or the side wall side buried portion is provided over the entire axial direction, but may be partially provided within the range.

It is a longitudinal cross-sectional view which shows schematic structure of the shear transmission structure of the underground tank by the 1st Embodiment of this invention. It is a principal part enlarged view of the shear transmission structure shown in FIG. It is the sectional view on the AA line shown in FIG. It is a longitudinal cross-sectional view which shows the structure of the shear transmission structure by 2nd Embodiment, Comprising: It is a figure corresponding to FIG. FIG. 5 is a sectional view taken along line B-B shown in FIG. 4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Underground tank 2 Continuous underground wall 3 Side wall 4 Bottom plate 10, 20 Shear transmission structure 11, 21 Slip bar (steel bar)
11a, 21a Continuous underground wall side buried portion 11b, 21b Side wall side buried portion 12, 22 Buffer material 13 Curing material 14 Insulating tape

Claims (2)

A shear transmission structure between a side wall and a continuous underground wall in an underground tank having a side wall and a bottom plate inside a continuous underground wall constructed in the ground,
A steel rod is embedded over both the continuous underground wall and the side wall,
A shear transmission structure between a side wall and a continuous underground wall in an underground tank, wherein a buffer material is provided on a side wall-side buried portion of the steel bar. A shear transmission structure between a side wall and a continuous underground wall in an underground tank having a side wall and a bottom plate inside a continuous underground wall constructed in the ground,
A steel rod is embedded over both the continuous underground wall and the side wall,
A shear transmission structure between a side wall and a continuous underground wall in an underground tank, wherein a buffer material is provided under the continuous underground wall side buried portion of the steel bar.

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