JP7033468B2 - Construction method of liquid barrier and liquid barrier - Google Patents

Description

The present invention relates to a method for constructing a liquid barrier and a liquid barrier.

Conventionally, for example, as a storage tank for storing liquefied natural gas, a structure having a storage tank provided with a steel outer tank and an inner tank, and a reinforced concrete liquid barrier constructed as an outer peripheral structure of the storage tank. Things are known. The outer tank is provided with a cylindrical outer tank liner plate on the outer peripheral side.
In the construction of the storage tank having such a configuration, the construction period is prolonged because the storage tank having the outer tank and the inner tank is constructed after the construction of the liquid barrier is completed. Therefore, as a construction method for shortening the construction period in the construction of the liquid barrier, for example, the construction method shown in Patent Documents 1 to 3 is known.

In Patent Document 1, a precast concrete formwork integrally provided with an outer tank liner plate is assembled as an inner formwork of a liquid barrier, and concrete is cast between the outer formwork assembled on the outer periphery of the inner formwork. A method of constructing a tank to be installed and to construct a formwork has been proposed. The construction method described in Patent Document 1 does not require an inner scaffolding for the liquid barrier, and the construction of the liquid barrier and the construction of the inner tank can be carried out at the same time after the foundation slab is constructed. It can be shortened.

Patent Document 2 describes a point in which an arc-shaped stiffener extending in the circumferential direction is connected to the outer peripheral surface of a formwork material, and a wall-shaped structure is constructed using a structure in which a reinforcing bar is connected or integrated with the stiffener. Are listed. In this case, the structures connected in the circumferential direction have a structure in which stability can be maintained by connecting the respective stiffeners.
Further, in Patent Document 3, a reinforcing bar pedestal which extends in the vertical direction and has a through hole formed in the reinforcing bar pedestal in the circumferential direction is connected to the outer tank liner plate, and the diameter of the outer tub is connected to the plurality of through holes. The configuration in which the inner reinforcing bars and the outer reinforcing bars arranged inside and outside the direction are inserted is described.

Japanese Unexamined Patent Publication No. 2010-106501 Japanese Unexamined Patent Publication No. 2017-223055 International Publication No. 2011/006213

However, in the conventional liquid barrier construction method, the liner plate assembled in advance may be bent and deformed due to its own weight, and there is a problem in installation accuracy. Therefore, there is a problem that it takes time and effort to position the liner plates and connect the liner plates to each other.

Further, when the structure is assembled in advance of the adjacent structure in the circumferential direction as in Patent Document 2, the structure can be attached to the preceding structure, so that the posture is stable. However, when the structure is installed independently without the structure installed in advance next to the circumferential direction, the structure becomes unstable and the installation accuracy is lowered. .. Moreover, in the case of Patent Document 2, since the stiffener extends along the circumferential direction, the vibrator thrown in from above when placing the concrete interferes with the stiffener and cannot be inserted to the lower side. There was a problem that the compaction was insufficient and the desired quality could not be ensured.

Further, in the case of Patent Document 3, since both the inner reinforcing bar and the outer reinforcing bar are inserted and attached to the through holes of the reinforcing bar pedestal, it takes time and effort. Further, in Patent Document 3, since the reinforcing bar pedestal connected to the outer tank liner plate positions and supports the reinforcing bar at a predetermined position, the reinforcing bar pedestal is used as a hanging tool for lifting a heavy outer tank liner plate. The through holes formed cannot be utilized. Therefore, it is necessary to install the suspended steel material as a separate member, which is troublesome.
As described above, as a method for constructing a liquid barrier, there is a demand for a construction method that can achieve a good balance of construction efficiency, construction accuracy, and quality, and there is room for improvement in that respect.

The present invention has been made in view of the above-mentioned problems, and provides a method for constructing a liquid barrier, which can improve construction efficiency and accuracy, and can suppress deterioration of quality, and a liquid barrier. The purpose is.

In order to achieve the above object, in the method for constructing the liquid barrier according to the present invention, a plurality of lots in which a cylindrical and reinforced concrete liquid barrier provided along the outer tank of the storage tank is divided in the circumferential direction and the vertical direction. It is a method of constructing a liquid barrier in which inner and outer reinforcing bars are embedded inside and outside the radial direction of the liquid barrier, which is constructed for each concrete, and is located on the inner peripheral surface of the lot. The arcuate outer tank liner plate constituting the outer tank and the inner reinforcing bar arranged on the outer peripheral side of the outer tank liner plate and embedded in the concrete were placed in a horizontal position with the outer peripheral surface facing downward. A step of integrally assembling the liner unit into a unit in a state, a step of arranging the liner unit at a predetermined position of the liquid barrier in a vertical position with the outer peripheral surface in the vertical direction, and a step of arranging the liner unit in a vertical direction, and an outer peripheral side of the liner unit. In the step of unitizing the liner unit, which comprises a step of providing an arc-shaped formwork at intervals and a step of filling concrete between the outer tank liner plate and the formwork. A step of providing a vertical reinforcing material extending in the vertical direction and having a plurality of through holes formed at intervals in the vertical direction on the outer surface of the outer tank liner plate in the vertical position, and the step of providing the vertical reinforcing material. A step of inserting an inner horizontal bar extending in the circumferential direction in each of the plurality of through holes and attaching the inner vertical bar to the inner horizontal bar, and providing a reinforcing bar support member extending in the radial direction in the vertical reinforcing material. It is characterized by having a step of supporting the outer reinforcing bar so as to have the outer horizontal bar and the outer vertical bar of the outer reinforcing bar.

Further, in the liquid barrier according to the present invention, a cylindrical reinforced concrete structure provided along the outer tank of the storage tank is formed, and inner reinforcing bars and outer reinforcing bars arranged inside and outside in the radial direction are embedded in the concrete. An arc-shaped outer tank liner plate that is a liquid embankment and is located on the inner peripheral surface of the concrete and constitutes the outer tank, and an outer surface of the outer tank liner plate that extends in the vertical direction and is spaced in the vertical direction. It is provided with a vertical reinforcing material in which a plurality of through holes are formed by opening a hole, and a reinforcing bar supporting material provided in the vertical reinforcing material and extending in the radial direction. The vertical reinforcing material is inserted into each of the plurality of through holes, and the inner vertical bars are arranged in a state of being attached to the inner horizontal bars. It is characterized by being arranged in a supported state so as to accompany it.

In the present invention, the liner unit can be provided by integrally assembling the vertical reinforcing material, the inner reinforcing bar, and the outer reinforcing bar to the outer surface of the outer tank liner plate arranged in the horizontal position. Since the vertical reinforcing material reinforces the outer tank liner plate and has sufficient strength, the liner unit is placed in a vertical position and lifted by a crane or the like using the through hole of the vertical reinforcing material to provide a liquid barrier. Can be placed in a predetermined position. After that, by providing a formwork and filling concrete, it is possible to construct a lot at the place where the liner unit is arranged. Then, a liquid barrier can be constructed by constructing a plurality of lots.
As described above, in the present invention, since there is no work at height and the work can be unitized as a liner unit by working with a ground structure in a good working condition, the work at height can be reduced, the work efficiency can be improved, and the outer tank can be improved. The inner and outer reinforcing bars can be incorporated into the liner plate accurately and efficiently. Further, in the present invention, it is possible to reduce the work on the upper part of the liquid barrier during the construction of the liquid barrier, so that the construction period can be shortened.

Further, in the present invention, since the outer tank liner plate is reinforced by the vertical reinforcing material, the outer tank is placed in a vertical position at a predetermined position as a liquid barrier in a state where the liner unit is placed vertically before the concrete is placed. It is possible to prevent the liner plate from bending and deforming in the direction in which it falls. Therefore, the amount of displacement of the position of the outer tank liner plate before the concrete is placed can be suppressed to a small size, and the liquid barrier and the outer tank of the storage tank after the concrete is placed can be constructed with high accuracy.

Further, in the present invention, only the inner and horizontal reinforcing bars of the inner reinforcing bar are inserted into the through holes of the vertical reinforcing material, and the outer reinforcing bars are only supported by the reinforcing bar supporting material. Can be minimized, and the reinforcing bar assembly work can be performed easily and efficiently.
Further, in the present invention, since the vertical reinforcing material is arranged in a state of being extended in the vertical direction with respect to the outer tank liner plate, when concrete is placed between the outer tank liner plate and the formwork. , The vibrator can be inserted from above to below the casting area. Therefore, the placed concrete can be sufficiently compacted and the quality can be ensured.

Further, in the method of constructing the liquid barrier according to the present invention, the liner units connected in the vertical direction are connected to the upper end portion of the vertical reinforcing material in the lower liner unit and the vertical reinforcing material in the upper liner unit. It is preferable that the lower end portion of the is abutted and fixed.

In this case, since the ends of the vertical reinforcing members of the upper and lower lots are fixed to each other by the fixing means, the liner units before the concrete is placed can be arranged in a stable posture. Therefore, the position of the outer tank liner plate on the liquid barrier can be accurately arranged.

Further, in the method of constructing the liquid barrier according to the present invention, the outer peripheral surfaces of the vertical reinforcing materials connected vertically are provided with reinforcing ribs connected over the outer peripheral surface of the vertical reinforcing materials. preferable.

In the present invention, since the connection between the vertical reinforcing members of the liner units arranged above and below is further reinforced by the reinforcing ribs, the liner units before the concrete is placed can be arranged in a more stable posture to prevent them. The position of the outer tank liner plate on the liquid embankment can be accurately arranged.

Further, in the method of constructing the liquid barrier according to the present invention, it is preferable that the formwork is fixed to a separator connected so as to project from the outer peripheral surface of the vertical reinforcing material.

In this case, the end portion of the separator for the formwork on the outer tank liner plate side can be fixed to the outer peripheral surface of the vertical reinforcing material having less deformation than the outer tank liner plate having insufficient installation accuracy. .. Therefore, it is possible to reduce the labor required for the work of adjusting the length of the separator, and it is possible to arrange the formwork with high accuracy.

According to the method of constructing the liquid barrier and the liquid barrier of the present invention, it is possible to improve the construction efficiency and the construction accuracy, and it is possible to suppress the deterioration of the quality.

It is a vertical sectional view which shows the schematic structure of the storage tank by embodiment of this invention. It is a vertical sectional view which shows the construction state of the liquid barrier of the storage tank shown in FIG. It is a side view of a liner unit. It is a side view which saw the liner unit from the outer peripheral side, and is the figure which omitted a part of the buried member. It is a side view which saw the liner unit from the outer peripheral side, and is the figure which omitted a part of the buried member. It is a side view which saw the liner unit from the outer peripheral side, and is the figure which omitted a part of the buried member. It is a side view which shows the connection part between the vertical reinforcing members of the upper and lower liner units. It is a side view which looked at the connection part shown in FIG. 7 from the outer peripheral side. It is a side view of the state where the formwork is installed in the liner unit, and is the figure corresponding to FIG.

Hereinafter, the method of constructing the liquid barrier and the liquid barrier according to the embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the liquid barrier 1 according to the present embodiment is constructed over the entire circumference of the outer peripheral side of the circular storage tank 10 in a plan view for storing LNG. That is, the storage tank 1A has a configuration including a liquid barrier 1 and a storage tank 10. The liquid barrier 1 is a reinforced concrete structure, which is constructed by prestress concrete, and is constructed by unitizing buried members 4 (see FIGS. 3 and 4) such as reinforcing bars and reinforcing steel materials to be buried in the concrete at the time of construction. It was constructed by a construction method aimed at improving efficiency.

Here, in the following description, in the storage tank 10 constituting the storage tank 1A and the liquid barrier 1, the direction orthogonal to the tank center axis O is defined as the radial direction X1, and the direction is defined as the radial direction X1 and is rotated around the tank center axis O. The direction is defined as the circumferential direction X2, and the direction along the tank center axis O is defined as the vertical direction X3. Then, in the radial direction X1, the side closer to the tank center axis O is defined as the inner peripheral side, and the opposite direction is defined as the outer peripheral side.

The storage tank 10 is constructed on a plurality of support piles 11, 11, ... Which are buried in the ground and are supported on a reinforced concrete foundation board 12. The storage tank 10 includes a bottom wall 13 arranged on the foundation board 12, an outer tank 14 and an inner tank 15 located on the outer peripheral portion of the bottom wall 13, and a top wall 16 covering the upper opening of the outer tank 14. It is equipped with.

The outer tank 14 and the inner tank 15 are each formed in a circular shape when viewed from above. The outer tank 14 is coaxially arranged on the outer peripheral side of the inner tank 15 at intervals. The outer tank 14 and the inner tank 15 are provided with an outer tank liner plate 2 and an inner tank liner plate 17 on the outer peripheral side of each. The top wall 16 is composed of an outer peripheral side and an inner peripheral side liner plate continuously connected to the upper end portion of the outer tank liner plate 2 and the inner tank liner plate 17. The space inside the bottom wall 13, the space between the outer tank 14 and the inner tank 15, and the space inside the top wall 16 are filled with a cold insulating material.

The outer tank liner plate 2 constitutes the outer peripheral surface of the outer tank 14, and is made of a steel plate curved in the circumferential direction X2. The inner tank liner plate 17 is arranged on the inner side surface 2b side of the outer tank liner plate 2 at intervals.

The liquid barrier 1 is a cylindrical concrete structure arranged on the foundation board 12 along the outer peripheral surface of the outer tank 14 and coaxial with the storage tank 10. In the storage tank 1A, as shown in FIG. 2, the concrete facing the inner side surface 1a of the liquid barrier 1 and the outer tank liner plate 2 of the outer tank 14 are integrally provided.

As shown in FIG. 2, the liquid barrier 1 includes a concrete portion 3 provided on the outer peripheral side of the outer tank liner plate 2 of the outer tank 14 with a predetermined thickness, and a buried member 4 (embedded in the concrete portion 3). (See FIG. 3) and. In the present embodiment, as a method of constructing the liquid barrier 1, a plurality of liner units 20 in which the outer tank liner plate 2 and the burial equipment 4 are integrally assembled by groundwork to form a unit are used, and these are placed at predetermined positions. The construction method by building is adopted.

The liquid barrier 1 is constructed by a construction method in which a plurality of lots P divided into the circumferential direction X2 and the vertical direction X3 are sequentially stacked from the lower side to the upper side. That is, a plurality of lots P are sequentially connected to each other in the circumferential direction X2 at the bottom stage (first stage), and further, the second stage lot P2 (P), the third stage lot P3 (P), and so on.・ Install. For the construction of each lot P, for example, the liner unit 20 unitized by grounding in a temporary storage space at the site is set at a predetermined construction position of the liquid barrier 1, and the outer surface of the lot P and the opening in the circumferential direction X2. After installing the formwork 5 in the portion (the 褄 portion), the work is carried out by filling the space between the formwork 5 and the outer tank liner plate 2 of the liner unit 20 with concrete.
Here, as an example of the size of each lot P of the liquid barrier 1, when the total circumference of the liquid barrier 1 is 270 m and is divided into 24 in the circumferential direction X2, the peripheral length is about 11.5 m and the height is high. It will be 5.6 m.

Next, a specific configuration of the liner unit 20 will be described with reference to the drawings. Here, in the following description, the liner unit 20 will be described in a state where it is arranged at a predetermined construction position of the liquid barrier 1.
As shown in FIGS. 3 and 4, the liner unit 20 is unitized by integrally assembling the outer tank liner plate 2 and the above-mentioned buried member 4, and one lot P of the liquid barrier 1 shown in FIG. The configuration is set to the shape and size corresponding to. The dimensions of the outer tank liner plate 2 in the liner unit 20 are, for example, 11.6 m in circumference and 5.6 m in height.

On the outer surface 2a of the outer tank liner plate 2, a plurality of vertical reinforcing members 21 extending in the vertical direction X3 of the outer surface 2a and arranged at intervals in the circumferential direction X2 and vertically extending along the circumferential direction X2. It is provided with a lateral reinforcing member 22 connected to the reinforcing member 21.

As shown in FIG. 3, the vertical reinforcing material 21 is made of H-shaped steel, and the inner flange 211 is welded to the outer surface 2a of the outer tank liner plate 2 except for the upper portion (non-fixed portion 21a described later). Is fixed by. The web 212 of the vertical reinforcing member 21 is formed so that a plurality of through holes 213 are arranged in a row at predetermined intervals in the vertical direction X3. The inner horizontal bar 41A of the inner reinforcing bar 41, which will be described later, is inserted into these through holes 213. Therefore, the through holes 213 are provided at intervals corresponding to the arrangement intervals of the inner horizontal bars 41A of the inner reinforcing bars 41 (see FIGS. 4 and 5).

Here, FIG. 4 is a view showing the liner unit 20, in which the left side region R1 divided by the breaking lines in the left-right direction of the paper surface shows all the buried members 4, and the central region R2 is in a state where the outer reinforcing bars 42 are omitted. The right side region R3 shows a state in which the outer reinforcing bar 42 and the sheath pipe 43 are omitted. FIG. 5 is a diagram in which the outer reinforcing bar 42, the sheath pipe 43, and the lateral reinforcing material 22 are omitted in the liner unit 20. FIG. 6 is a diagram showing only the outer tank liner plate 2 and the sheath tube 43.

As shown in FIG. 3, the upper portion of the vertical reinforcing member 21 has a non-fixed portion 21a that is not fixed to the outer tank liner plate 2. The lower end portion 2d of the outer tank liner plate 2 on the upper side of the liner unit 20 connected from above is inserted between the non-fixed portion 21a of the vertical reinforcing member 21 and the outer tank liner plate 2. As a result, the upper and lower outer tank liner plates 2 are connected to each other in a state of overlapping in the radial direction X1.

As the lateral reinforcing member 22, a pair of angle members having an L-shaped cross section arranged at intervals in the radial direction X1 are used. A plurality (here, two places) of the pair of lateral reinforcing members 22 are arranged in the vertical direction X3. The horizontal reinforcing material 22 on the inner peripheral side is fixed to the outer flange surface 21c (outer peripheral surface of the vertical reinforcing material 21) of the vertical reinforcing material 21 by welding. The lateral reinforcing material 22 on the outer peripheral side is fixed to the tip of the reinforcing bar support material 22A extending in the radial direction X1 from the outer flange surface 21c of the vertical reinforcing material 21 by welding.

As shown in FIGS. 3 and 4, the buried member 4 is integrally assembled with the outer tank liner plate 2. The buried member 4 is peripheral to the inner reinforcing bar 41 arranged closer to the outer tank liner plate 2, the outer reinforcing bar 42 arranged at intervals from the inner reinforcing bar 41 to the outer peripheral side, and the inner reinforcing bar 41 and the outer reinforcing bar 42. It has a sheath tube 43 extending in the direction X2 and the vertical direction X3.

As shown in FIGS. 3 to 5, the inner reinforcing bars 41 are arranged in a grid pattern along the circumferential direction X2 and the vertical direction X3. The inner horizontal bar 41A of the inner reinforcing bar 41 extending in the circumferential direction is curved along the circumferential direction X2 and is arranged at a position spaced from the outer surface 2a to the outer peripheral side. As described above, the inner horizontal bar 41A is arranged in a state of being passed through the through hole 213 formed in the web 212 of the plurality of vertical reinforcing members 21.
The inner vertical bar 41B of the inner reinforcing bar 41 extending in the vertical direction X3 extends linearly in the vertical direction X3 and is connected to the outside of the inner horizontal bar 41A. The upper end portion 41a and the lower end portion 41b of the inner vertical bar 41B project outward from the upper end portion 2c and the lower end portion 2d of the outer tank liner plate 2, respectively.

As shown in FIGS. 3 and 4, the outer reinforcing bars 42 are arranged in a grid pattern along the circumferential direction X2 and the vertical direction X3. The outer lateral reinforcing bar 42A of the outer reinforcing bar 42 extending in the circumferential direction X2 is curved along the circumferential direction X2 and is arranged at a position spaced outward from the outer surface 2a.
The outer vertical bar 42B of the outer reinforcing bar 42 extending in the vertical direction X3 extends linearly in the vertical direction X3 and is connected to the inside of the outer horizontal bar 42A. Specifically, the outer horizontal bar 42A and the outer vertical bar 42B are supported so as to be attached to the outer lateral reinforcing member 22 fixed to the reinforcing bar support member 22A.
The upper end portion 42a of the outer vertical bar 42B is set to be lower than the upper end portion 41a of the inner vertical bar 41B of the inner reinforcing bar 41. The lower end portion 42b of the outer vertical bar 42B protrudes outward from the lower end portion 2d of the outer tank liner plate 2.

The sheath pipe 43 is composed of a horizontal sheath pipe 43A extending in the circumferential direction X2 and a vertical sheath pipe 43B extending in the vertical direction X3, and a PC steel wire (not shown) is inserted into the sheath pipe 43 after concrete is placed. Prestress is introduced into the concrete portion 3 (see FIG. 2).

Next, the construction method of the liquid barrier 1 will be specifically described with reference to the drawings.
First, the above-mentioned liner unit 20 shown in FIGS. 3 and 4 is grounded at the construction site. That is, after the outer tank liner plate 2 is arranged with its outer surface 2a facing upward, the buried member 4 is sequentially assembled to the outer tank liner plate 2 to form a unit.

First, as shown in FIGS. 3, 4 and 5, the outer tank liner plate 2 is arranged in a horizontal position with its outer surface 2a facing up. Then, after a plurality of vertical reinforcing members 21, 21, ... Are fixed to the predetermined positions on the outer surface 2a by welding, the horizontal reinforcing members 22 are fixed to these vertical reinforcing members 21, 21, ... By welding. In the vertical reinforcing material 21, a plurality of through holes 213 are formed in advance so as to be arranged in a row at a factory or the like.
After that, the inner horizontal bar 41A of the inner reinforcing bar 41 is inserted into the through hole 213 formed in the web 212 of each vertical reinforcing member 21 and arranged along the circumferential direction X2. Further, a plurality of inner vertical bars 41B are arranged on the outer peripheral side of the inner horizontal bars 41A. The inner vertical bar 41B may be bound to the inner horizontal bar 41A or may be mechanically connected.

Next, as shown in FIGS. 3, 4, and 6, a plurality of sheath pipes 43 are arranged in the outer peripheral region of the inner reinforcing bar 41. First, the vertical sheath pipe 43B is arranged so as to extend in the vertical direction X3 along the vertical reinforcing member 21 so as to be adjacent to the vertical reinforcing member 21, and is tightly fixed to the vertical reinforcing member 21. Further, once all the vertical sheath tubes 43B, 43B, ... Are fixed, the horizontal sheath tubes 43A, 43A, ... Arranged at intervals in X3, tightly fixed to the vertical sheath tube 43B.

Subsequently, as shown in FIGS. 3 and 4, the outer reinforcing bar 42 is arranged on the outer peripheral side of the sheath tube 43. First, a plurality of outer vertical bars 42B of the outer reinforcing bars 42 are connected to the lateral reinforcing member 22 fixed to the reinforcing bar support member 22A so as to be arranged at intervals in the vertical direction X3. Further, a plurality of outer horizontal bars 42A, 42A, ... Are arranged by supporting them so as to be along the outer peripheral side of the outer vertical bars 42B and binding them to the outer vertical bars 42B.
As a result, the assembly of the liner unit 20 for one lot P as shown in FIG. 2 is completed.

Here, as shown in FIG. 1, the storage tank 1A is constructed up to the state before the construction of the storage tank 10 and the liquid barrier 1. That is, a plurality of support piles 11, 11, ... Are placed on the ground at the construction site of the storage tank 1A, and a reinforced concrete foundation board 12 is constructed on the upper ends (pile heads) of the support piles 11, 11, ... ing. Then, the liner unit 20 unitized by the groundwork as described above is sequentially assembled on the outer peripheral portion of the foundation board 12.
Specifically, as shown in FIG. 2, the crane M is used to lift the liner unit 20 arranged horizontally on the ground so as to be assembled, and to position the base plate 12 at a predetermined position. , It is fixed to the base plate 12 by an appropriate fixing means.

Here, an example is in which the bottom lot (first stage) lot P1 is assembled on the foundation board 12 in the circumferential direction X2 over the entire circumference, and then the second lot P2 is constructed on the first lot P1. Is shown.
In FIG. 2, the construction of the first and second lots P1 and P2 is completed, and the liner unit 20 of the third lot P3 is placed on the second lot P2 and concrete is cast. It shows the construction status of the installation.

As shown in FIG. 7, the leading liner unit 20A (20) located on the lower side and fixed in advance and the trailing liner unit 20B (20) connected to the upper side of the leading liner unit 20A are attached. When connecting, the end faces 21d and 21e of both the upper and lower vertical reinforcing members 21A and 21B are brought into contact with each other. That is, the lower end surface 21e of the vertical reinforcing material 21B connected from above is brought into contact with the upper end surface 21d of the lower vertical reinforcing material 21A.

Then, as shown in FIGS. 7 and 8, the T-shaped reinforcing member 24 (reinforcing rib) having a T-shaped cross section is fixed by the bolt 24c so as to bridge the outer flange surfaces 21c and 21c of the vertical reinforcing members 21A and 21B. Has been done. The T-shaped reinforcing member 24 has a fixing plate 24a that is brought into contact with the outer flange surface 21c on the surface and a rib 24b that is vertically provided with respect to the fixing plate 24a, with respect to the lower vertical reinforcing member 21A. It is a member that reinforces the upper vertical reinforcing member 21B so that it does not fall over.

Further, as shown in FIG. 7, the connection structure of the outer tank liner plates 2A and 2B in the vertical direction X3 is such that the upper end portion 2f of the outer tank liner plate 2A and the non-fixed portion 21a of the vertical reinforcing member 21A in the preceding liner unit 20A. The lower end portion 2g of the outer tank liner plate 2B of the trailing liner unit 20B is inserted from above by expanding and deforming the upper end portion 2f of the lower outer tank liner plate 2A. 2A and 2B form an overlapping portion 2h on which they overlap and are connected to each other. Then, by welding the upper end portion 2c of the lower outer tank liner plate 2A to the inner side surface 2b of the upper outer tank liner plate 2B (this welded portion is indicated by the symbol W), the upper and lower outer tank liner plates are formed. 2A and 2B are connected to each other.

Then, along with the connection between the upper and lower vertical reinforcing members 21A and 21B, the inner vertical reinforcing bar 41B of the inner reinforcing bar 41, the outer vertical reinforcing bar 42B of the outer reinforcing bar 42, and the vertical sheath pipe 43B also shown in FIG. 3 are the upper and lower liner units 20A and 20B. It is connected between them by an appropriate connection means. For example, the reinforcing bars are connected to each other by a mechanical method or a binding wire, and the sheath tubes are connected to each other by using, for example, an adhesive tape.

Next, after the assembly of the trailing liner unit 20B is completed, as shown in FIG. 2, a scaffold 53 is provided on the outer peripheral side of the assembled liner unit 20 to install the formwork 5. The formwork 5 is curved along the circumferential direction, and is arranged on the outer peripheral side from the outer tank liner plate 2 at a predetermined interval. As shown in FIG. 9, the formwork 5 is installed at a position maintained at regular intervals by a separator 51 suspended from the outer flange surface 21c of the vertical reinforcing material 21 by a fixing means such as welding, and is filled at the time of concrete placement. The concrete is prevented from swelling the formwork 5 toward the outer periphery.

Further, along with the installation of the formwork 5, a prestressed concrete steel wire (PC steel wire) (not shown) is inserted into the horizontal sheath pipe 43A and the vertical sheath pipe 43B. The PC steel wire inserted into the horizontal sheath pipe 43A is arranged so that the fixing end protrudes to the outside of the concrete portion 3. Further, a PC steel wire inserted through the vertical sheath pipe 43B of the lower leading liner unit 20A is inserted into the vertical sheath pipe 43B.

Next, as shown in FIG. 2, the space between the outer tank liner plate 2 and the formwork 5 is filled with concrete from above. As a result, the construction of one lot P is completed, and as described above, a plurality of lots P are sequentially constructed in the circumferential direction X2 and the vertical direction X3. Then, after the concrete placement in all lots P of the liquid barrier 1 is completed, the tension end of the PC steel wire is pulled to give tension to the concrete portion 3, and the construction of the liquid barrier 1 is completed. The outer tank liner plate 2, which is a part of the outer tank 14, is also installed at a predetermined position on the liquid barrier 1 constructed at this time.
After all the lots P of the liquid barrier 1 have been constructed, the PC steel wire is inserted into the sheath pipes 43A and 43B connected between the lots P, and a tensile force is applied to the PC steel wire to apply concrete. Prestress may be introduced into the part 3.

After constructing the liquid barrier 1, as shown in FIG. 1, a storage tank 10 is constructed on the inner peripheral side of the outer tank liner plate 2 installed together with the liquid barrier 1. That is, the bottom wall 13 of the storage tank 10, a part of the outer tank 14 other than the outer tank liner plate 2, the inner tank 15, and the top wall 16 are sequentially constructed, and the bottom between the outer tank 14 and the inner tank 15 is constructed. The space inside the wall 13 and the top wall 16 is filled with a cold insulating material to complete the construction of the storage tank 10, and the storage tank 1A is completed.

Next, the construction method of the liquid barrier and the operation of the liquid barrier will be described in detail based on the drawings.
As shown in FIG. 3, in the present embodiment, the vertical reinforcing member 21 and the buried member 4 (inner reinforcing bar 41, outer reinforcing bar 42, etc.) are provided with respect to the outer surface 2a of the outer tank liner plate 2 arranged in the horizontal position. The liner unit 20 can be provided by being integrally assembled. Since the vertical reinforcing material 21 reinforces the outer tank liner plate 2 and has sufficient strength, the liner unit 20 is placed in a vertical position as shown in FIG. 2, and the through hole 213 of the vertical reinforcing material 21 is provided. It can be lifted by the crane M and placed at a predetermined position on the liquid barrier 1. After that, by providing the formwork 5 and filling the concrete, the lot P at the place where the liner unit 20 is arranged can be constructed. Then, the liquid barrier 1 can be constructed by constructing a plurality of lots P.

As described above, in the present embodiment, since the liner unit 20 can be unitized by the work with the groundwork in a good working condition without the work at a high place, the work at a high place can be reduced and the work efficiency can be improved. The inner reinforcing bar 41 and the outer reinforcing bar 42 can be incorporated into the outer tank liner plate 2 accurately and efficiently.

Further, in the present embodiment, since the outer tank liner plate 2 is reinforced by the vertical reinforcing material 21, the liner unit 20 is placed in a predetermined position as the liquid barrier 1 in a vertical position, and is made of concrete. It is possible to prevent the outer tank liner plate 2 from being curved and deformed in the direction of tilting before casting. Therefore, the amount of displacement of the position of the outer tank liner plate 2 before the concrete is placed can be suppressed to a small size, and the liquid barrier 1 and the outer tank 14 of the storage tank 10 after the concrete is placed can be constructed with high accuracy. ..

Further, in the present embodiment, only the inner horizontal reinforcing bar 41A of the inner reinforcing bar 41 is inserted into the through hole 213 of the vertical reinforcing material 21, and the outer reinforcing bar 42 is supported by the horizontal reinforcing material 22 via the reinforcing bar supporting material 22A. Therefore, the laborious work of inserting the reinforcing bar into the hole can be minimized, and the reinforcing bar assembling work can be performed easily and efficiently.

Further, in the present embodiment, since the vertical reinforcing material 21 is arranged in a state of being extended in the vertical direction with respect to the outer tank liner plate 2, concrete is placed between the outer tank liner plate 2 and the formwork. At the time of casting, the vibrator can be inserted from above to below the casting area. Therefore, the placed concrete can be sufficiently compacted and the quality can be ensured.

Further, in the construction method of the liquid barrier 1 according to the present embodiment, the ends of the vertical reinforcing members 21 of the upper and lower lots P are fixed to each other by the fixing means, so that the liner before concrete is placed. The units 20 and 20 can be arranged in a stable posture. Therefore, the position of the outer tank liner plate 2 on the liquid barrier 1 can be accurately arranged.

Further, in the method of constructing the liquid barrier of the present embodiment, as shown in FIG. 7, the vertical reinforcing members 21A and 21B of the liner units 20A and 20B arranged above and below are further connected by the T-shaped reinforcing member 24. Since it is reinforced, the liner units 20 and 20 before concrete placement can be arranged in a more stable posture, and the position of the outer tank liner plate 2 on the liquid barrier 1 can be accurately arranged.

Further, in the present embodiment, the end portion of the separator 51 for the formwork 5 on the outer tank liner plate 2 side is the outer flange of the vertical reinforcing material 21 having a smaller deformation than the outer tank liner plate 2 having insufficient installation accuracy. It can be fixed to the surface 21c. Therefore, it is possible to reduce the time and effort required for the work of adjusting the length of the separator 51, and the formwork 5 can be arranged with high accuracy.

As described above, in the method of constructing the liquid barrier according to the present embodiment and the liquid barrier, the construction efficiency and the construction accuracy can be improved, and the deterioration of the quality can be suppressed.

Although the method of constructing the liquid barrier and the embodiment of the liquid barrier according to the present invention have been described above, the present invention is not limited to the above-described embodiment and is appropriately modified without departing from the spirit of the present invention. It is possible.

For example, in the present embodiment, the liner units 20 and 20 connected in the vertical direction are connected to the upper end surface 21d of the vertical reinforcing material 21 in the lower liner unit 20 and the vertical reinforcing material 21 in the upper liner unit 20. The structure is such that the lower end surface 21e is brought into contact with each other to be fixed, but the present invention is not limited to this, and the ends of the upper and lower vertical reinforcing members 21 and 21 are not directly brought into contact with each other, for example, via a connecting member. It may be configured to be inserted and connected, or it may be configured not to fix the vertical reinforcing members 21 and 21 on both the upper and lower sides.
Further, in the present embodiment, the T-shaped reinforcing member 24 is provided as a reinforcing rib over the outer flange surfaces 21c of the vertical reinforcing members 21 and 21 connected vertically, but the member having a T-shaped cross section is provided as the reinforcing rib. It is also possible to omit the reinforcing ribs.

Further, the mounting position and the number of separators 51 used for installing the formwork 5 are not limited to the above-described embodiment, and can be appropriately set. That is, in the present embodiment, the end portion of the separator 51 on the outer tank liner plate 2 side is fixed to the outer flange surface 21c of the vertical reinforcing member 21, but the edge portion of the flange 211 of the vertical reinforcing member 21 is fixed. It may be fixed to.

Further, in the present embodiment, at the connecting portion between the outer tank liner plates 2 and 2 of the upper and lower liner units 20 and 20, the upper end portion 2f of the lower outer tank liner plate 2 and the upper outer tank liner plate 2 are connected. Although the lower end portion 2g is overlapped with the overlapping portion 2h, the connection structure is not limited to this.

Further, the size of one lot P in which the liquid barrier 1 is divided to determine the dimensions of the liner unit 20 can be appropriately set according to the size, shape, and number of divisions of the liquid barrier 1.
Further, in the present embodiment, the LNG tank is exemplified as the storage tank, but another tank such as a crude oil tank may be used.

In addition, it is possible to replace the components in the above-described embodiment with well-known components as appropriate without departing from the spirit of the present invention.

1 Liquid barrier 1A Storage tank 2 Outer tank liner plate 2a Outer side surface 3 Concrete part 4 Buried member 5 Formwork 10 Storage tank 14 Outer tank 20, 20A, 20B Liner unit 21, 21A, 21B Vertical reinforcement 21a Non-fixed part 21c Outer flange surface (outer peripheral surface of vertical reinforcing material)
213 Through hole 22 Horizontal reinforcing material 22A Reinforcing bar support material 24 T-shaped reinforcing member (reinforcing rib)
41 Inner Reinforcing Bar 41A Inner Horizontal Reinforcing Bar 41B Inner Vertical Reinforcing Bar 42A Outer Horizontal Reinforcing Bar 42B Outer Vertical Reinforcing Bar 43 Sheath Tube 51 Separator X1 Radial Direction X2 Circumferential Direction X3 Vertical Direction

Claims (5)

Cylindrical reinforced concrete liquid barriers provided along the outer tank of the storage tank are constructed for each of a plurality of lots divided in the circumferential direction and the vertical direction, and arranged inside and outside the radial direction of the liquid barrier in the concrete. It is a construction method of a liquid barrier in which the inner and outer reinforcing bars are buried.
An arcuate outer tank liner plate located on the inner peripheral surface of the lot and forming the outer tank, and the inner reinforcing bar arranged on the outer peripheral side of the outer tank liner plate and embedded in the concrete are formed on the outer circumference. The process of unitizing the liner unit by integrally assembling it in a horizontal position with the side facing down, and
A step of arranging the liner unit at a predetermined position on the liquid barrier in a vertical position with the outer peripheral surface in the vertical direction.
The process of providing an arc-shaped formwork at intervals on the outer peripheral side of the liner unit, and
The process of filling concrete between the outer tank liner plate and the formwork,
Have,
In the process of unitizing the liner unit,
A step of providing a vertical reinforcing material on the outer surface of the outer tank liner plate, which extends in the vertical direction in the vertical position and has a plurality of through holes formed at intervals in the vertical direction.
A step of inserting an inner horizontal bar extending in the circumferential direction in each of the plurality of through holes of the vertical reinforcing material and attaching the inner vertical bar to the inner horizontal bar.
The vertical reinforcing material is provided with a reinforcing bar support material extending in the radial direction, and the vertical reinforcing material is provided with a step of supporting the reinforcing bar supporting material so as to have the outer horizontal bars and the outer vertical bars of the outer reinforcing bar. Construction method of liquid barrier. The liner units connected in the vertical direction are fixed by abutting the upper end portion of the vertical reinforcing material in the lower liner unit with the lower end portion of the vertical reinforcing material in the upper liner unit. The method for constructing a liquid barrier according to claim 1. The construction of the liquid barrier according to claim 2, wherein the outer peripheral surfaces of the vertical reinforcing members connected to each other are provided with reinforcing ribs connected over the outer peripheral surfaces of the vertical reinforcing members. Method. The method for constructing a liquid barrier according to any one of claims 1 to 3, wherein the formwork is fixed to a separator connected so as to project from the outer peripheral surface of the vertical reinforcing material. .. It is a liquid barrier that is a cylindrical reinforced concrete structure provided along the outer tank of the storage tank and has inner and outer reinforcing bars arranged inside and outside in the radial direction embedded in the concrete.
An arcuate outer tank liner plate located on the inner peripheral surface of the concrete and constituting the outer tank, and
A vertical reinforcing material extending in the vertical direction and having a plurality of through holes formed at intervals in the vertical direction on the outer surface of the outer tank liner plate.
Reinforcing bar support material provided in the vertical reinforcing material and extending in the radial direction, and
Equipped with
In the inner reinforcing bar, the inner horizontal bar extending in the circumferential direction is inserted into each of the plurality of through holes of the vertical reinforcing material, and the inner vertical bar is arranged in a state of being attached to the inner horizontal bar.
The liquid barrier is characterized in that the outer horizontal bar and the outer vertical bar of the outer reinforcing bar are arranged in a state of being supported so as to be attached to the reinforcing bar support material.

Images