JPH04302799A - Underground type low-temperature tank roof building-up method - Google Patents

Abstract

PURPOSE:To enable simultaneous execution of the tub and roof building-up operation by causing a basic roof block, which has been formed by mounting a plurality of sectorial divisional roof members to a center portion of the future dome roof, to be placed from above down to the opening end surface of a tub member covering from side to side thereof, and then sequentially joining the remaining divisional roof members to the basic roof block. CONSTITUTION:In order to construct the roof, a bottomed-cylinder shaped concrete- made tub member 1, which is opened at its top, is built up under the ground, and a ring-like knuckle plate 2 is mounted thereon along the peripheral edge of the opening. On the other hand, for a roof portion 3 arc prepared a center portion 4 and sectorial divisional roof members. Next, a plurality of divisional roof members 5 arc attached to the center portion 4 to form a basic roof block 10. Subsequently, the basic roof block 10 is lifted up by, for example, a crane, and is transferred to over the opening of the concrete-made tub member 1. Then, the basic roof block is mounted to the knuckle plate 2 in such a manner as to be placed thereon covering from side to side thereof. Then, the other divisional roof members are sequentially joined to the basic roof block 10 to thereby build up the dome roof as a whole.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a novel method for constructing the roof of an underground low-temperature tank, and more particularly to a method for constructing the roof of an underground low-temperature tank that allows construction of the tank body and roof at the same time. .

0002

2. Description of the Related Art In general, underground low temperature tanks are known as tanks for storing low temperature liquids such as LPG and LNG. Conventionally, as shown in Fig. 7, this underground low-temperature tank is constructed by first constructing a bottomed cylindrical concrete tank body a with an open top underground, and then inserting an opening b into the concrete tank body a. An annular knuckle plate c is attached along the circumferential direction, and a dome-shaped roof d covering the opening is assembled inside the tank body a.

[0003] After assembling the dome-shaped roof d in the tank body a in this way, the roof d is raised inside the tank body a by air raising or jacking method, and its base end is attached to the knuckle plate c. Connected and installed.

A suspension deck f is suspended from the inside of the roof d for supporting a cold insulating material layer e covering the upper opening b of the tank body a. This suspension deck f is located at the bottom of the concrete tank body a.
It is attached to the roof d at the same time as the roof d is assembled. Therefore, when the roof d is moved upward by an air raising method or the like, the suspension deck f is also moved together. In this way, after the dome-shaped roof d is attached to the upper opening of the concrete tank body a, a cold insulation material layer g is interposed inside the concrete tank body a to substantially accommodate the low-temperature storage liquid. The underground low temperature tank is completed by installing a membrane panel to form an inner tank h.

[0005]

[Problems to be Solved by the Invention] In the construction of conventional underground cryogenic tanks, the period for constructing the roof d occupies approximately half of the period for constructing the entire tank. In particular, in the conventional roof construction method, a concrete tank a is installed underground.
After completing the construction, roof d is assembled inside the tank body, and after this is lifted and transferred by jacking up or air raising method, roof d is assembled because it will be attached to tank body a of the tank. During this period, there was a problem in that no work could be done inside tank body a.

Furthermore, unless the roof a is attached to the opening b at the top of the concrete tank body a, there is a problem in that the inner tank h cannot be assembled by attaching the cold insulation material layer g to the wall of the tank body. That is, when moisture enters the cold insulation material layer g, the cold insulation performance is impaired.

Therefore, the present invention was devised to effectively solve the above-mentioned problems, and its purpose is to improve the conventional method of constructing the roof of an underground cryogenic tank. The purpose of the present invention is to provide a method for constructing a roof for an underground low-temperature tank that can shorten the construction period.

[0008]

[Means for Solving the Problems] The present invention involves burying a bottomed cylindrical tank underground, providing a ring-shaped knuckle plate along the opening of the tank, and then attaching a ring-shaped knuckle plate to the knuckle plate. In the method of constructing a dome-shaped roof covering the opening by supporting the ends, the knuckle plate is attached, and a center part that divides the center top of the roof above the ground, and a plurality of outer peripheral parts of the center part are provided. At least two fan-shaped split roof pieces are formed, which are divided radially into individual pieces, and at least two
After attaching the two split roof pieces to form a basic roof block, the basic roof block is attached to the knuckle plate and spanned over the tank opening, and then the remaining split roof is sequentially attached to the center part and the knuckle plate. It was constructed by spanning the pieces and joining them together.

[0009]

[Operation] With the above configuration, first, the dome-shaped roof is divided and molded at the ground level into a center part that partitions the central peak and fan-shaped split roof pieces that are radially divided into a plurality of pieces on the outer periphery of this center part. As a result, these split roof pieces can be formed outside the tank construction site, which increases factory utilization and can be done in parallel with the concrete tank body construction work. In addition, after forming the basic roof block, this is attached to the knuckle plate and spanned over the tank opening, and the remaining split roof pieces are successively joined to this basic roof block. The basic roof block created can be used as a working base, and the roof can be constructed without using pillars from the bottom to support the roof or special scaffolding.

Furthermore, the opening of the concrete tank body is covered by sequentially joining the split roof pieces, and a layer of cold insulation material is attached to the wall of the tank body depending on the covered part, and the inner tank is closed. can be assembled, shortening the construction period for the entire tank.

[0011]

EXAMPLES Specific examples of the present invention will be described in detail with reference to the drawings.

First, as shown in FIG. 3, a bottomed cylindrical concrete tank 1 with an open top is constructed underground, and along the periphery of the opening of this concrete tank 1, A ring-shaped knuckle plate 2 is integrally attached. At the same time, as shown in FIG. 1, the dome-shaped roof 3 is divided into a center part 4 that divides its central top and fan-shaped divided roof pieces 5 to divide the outer circumference of the center part 4 into a plurality of parts radially. Split mold. The center portion 4 and the split roof pieces 5 are formed at a factory or at a field assembly site. Each split roof piece 5 has a roof frame 7 as its basic structure, and is constructed by attaching a roof plate 5a and a split piece 6a of a suspension deck 6 to the roof frame 7. Also, the center part 4
consists of a strength ring 8 and a roof plate 9 covering it.

Next, the basic roof block 10 is formed by attaching at least two of the above-mentioned split roof pieces 5 to the center portion 4 formed in this manner so as to face each other as shown in FIG. As shown in the figure, this basic roof block 10 includes a reinforcing material 1 such as a tie rod for strength as one of the component parts.
Use 3. The suspension deck 6 is attached to the roof frame 7 via a suspension rod 11, and has a disk portion 12 at its center that has approximately the same shape as the center portion 4 described above. A divided piece 6a of a suspension deck 6 suspended from each divided roof piece 5 is connected to this disc portion 12. The basic roof block 10 assembled in this way is suspended by a crane or the like and transferred to the upper opening of the concrete tank body 1, and then attached to the knuckle plate 2 and moved to the opening of the tank body as shown in FIG. passed on to the superiors. After the basic roof block 10 is spanned over the knuckle plate 2 in this way, another divided roof piece 5 is joined to this basic roof block 10 as shown in FIG. In particular, when joining the divided roof pieces 5, they are joined around the basic roof block 10 so as to face each other, and the strength of the whole is gradually increased.

Each split roof piece 5 is mainly composed of a fan-shaped roof frame 7 and a roof plate 5a attached to the outside thereof, as described above, and a suspension deck is provided on the inside of this split roof piece 5. 6 is installed. In particular, as shown in FIG. 4, these roof pieces 5 are assembled around a workbench 14. This workbench 14 has a cross section substantially equal to the center portion 4 and is configured to constitute a work jig and facilitate the connection of the split roof piece 5 to the basic roof block 10. There is. The split roof pieces 5 are integrally assembled by abutting the upper end of the roof frame 7 on the workbench 14, abutting the axial center of the suspension deck 6, and connecting each other with the hanging rods 11.

The split roof pieces 5 assembled in this manner are sequentially transported by a crane or the like and, as described above, are sequentially joined with the basic roof blocks 10 in between, as shown in FIG. 5, to assemble the roof. Further, as shown in FIG. 6, the roof plates 5a constituting each divided roof piece 5 have engaging portions 15 on adjacent sides so as to mesh and engage with each other.

As described above, according to the method of the present invention, first, the dome-shaped roof 3 is divided into a center portion 4 defining the center top of the dome-shaped roof 3 at the ground level, and a fan-like shape in which the outer periphery of the center portion 4 is radially divided into a plurality of pieces. By forming the roof pieces 5 separately into the split roof pieces 5, these split roof pieces 5 can be formed outside the tank construction site, which increases the factory operating rate and can be completed in parallel with the construction work of the concrete tank body 1. obtain.

Furthermore, after forming the basic roof block 10, it is attached to the knuckle plate 2 and stretched over the opening of the tank body, thereby sequentially joining the remaining split roof pieces 5 to this basic roof block 10. Therefore, the above-mentioned basic roof blocks 10 can be used as a work base, and the roof can be constructed without using pillars from the bottom or special scaffolding for supporting the roof.

Furthermore, the roof 3 covers the opening of the concrete tank body 1 by sequentially joining the split roof pieces 5, and a layer of cold insulation material is attached to the wall of the tank body depending on the covered part. The inner tank can be assembled using the same method, and the construction period for the entire tank can be shortened.

[0019]

[Effects of the Invention] According to the present invention, since the tank body and the roof can be constructed at the same time, the construction period for the entire underground low temperature tank can be shortened.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of a roof for explaining the method of the present invention.

FIG. 2 is a schematic perspective view showing a step of assembling a basic roof block, which is one step of the present invention.

FIG. 3 is a schematic side sectional view of a cryogenic tank for explaining the method of the present invention.

FIG. 4 is a schematic perspective view of a split roof piece for explaining the method of the invention.

FIG. 5 is a schematic perspective view showing a step of joining split roof pieces, which is one step of the present invention.

FIG. 6 is a schematic diagram of a roof plate engaging portion of a split roof according to the present invention.

FIG. 7 is a side sectional view showing a conventional example.

[Explanation of symbols]

1 Tank body 2 Roof outer structure 3 Roof 4 Center part 5 Split roof pieces 10 Basic roof block

Claims (1)

[Claims] Claim 1: After burying a bottomed cylindrical tank underground and providing a roof outer structure such as a ring-shaped knuckle plate along the opening of the tank, the roof outer structure is A method for constructing a dome-shaped roof that covers the opening by supporting the base end of the roof, the center portion attaching the roof outer peripheral structure and partitioning the center top of the roof at the ground level; The outer periphery of the portion is divided into a plurality of radially divided fan-shaped roof pieces, and at least two pieces are formed facing the center portion.
After attaching the two split roof pieces to form a basic roof block, the basic roof block is attached to the roof outer peripheral structure and spanned over the tank opening, and then the center part and the roof outer structure are connected. A method for constructing a roof for an underground low-temperature tank, characterized in that the remaining split roof pieces are successively spanned and joined to construct the entire roof.