JP2990769B2 - Roof construction method for underground cryogenic liquid storage tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for constructing a roof portion of an underground low-temperature storage tank for storing a low-temperature liquid such as LNG, and in particular, a large diameter of about 60 m in diameter. TECHNICAL FIELD The present invention relates to a method for constructing a roof part of an underground low-temperature storage tank, which has achieved a shortened construction period of a roof part having the above.

[Prior Art] In recent years, underground low-temperature storage tanks for storing low-temperature liquids such as LNG have been buried underground with a bottomed cylindrical concrete tank in order to increase the storage capacity. Construction,
A dome-shaped roof is attached to the upper opening of the buried tank. And this roof diameter is
It has a large diameter of about 60m.

Conventionally, the construction method of this dome-shaped roof portion is the eighth method.
As shown in the figure, a wide space in a bottomed cylindrical tank body a buried underground and built is effectively used. First, materials such as a roof bone c and a roof plate d constituting the roof portion b are sequentially loaded into the tank body a, and a temporary support or a temporary support base f is assembled on the bottom plate e of the tank body a.

Next, the roof bone c is assembled along the temporary support f thus assembled. The roof bone c is composed of vertical bones g extending radially outward and radially from the roof top, and these vertical bones g.
And a transverse bone h that is tied and bridged therebetween.

After being assembled from the roof bone c in this manner, a roof plate d is stretched outside the roof bone c, and a roof frame i having a circular dome shape is completed. In addition, a cooling material layer for shutting off external heat input is integrally attached to the roof frame i. In this case, a cooling material j is stretched and attached inside the roof frame i in advance. The roof part b completed in this way is moved upward to the upper part of the tank body a by the air-raising or jack-up method, and is connected and fixed to the knuckle plate k provided in advance at the upper opening edge of the tank body a. The installation of the roof part b is completed.

[Problems to be Solved by the Invention] In the above-described conventional roof construction method, the construction period occupies about half of the construction period of the entire underground low-temperature storage tank. However, there is an inconvenience that the demands of consumers cannot be satisfied promptly due to prolongation. In addition, there is a disadvantage that the entire construction period is extended over a long period of time, resulting in an increase in personnel costs and the like.

Therefore, the present invention has been devised in order to effectively solve the above-described drawbacks, and an object of the present invention is to improve the construction method of the roof portion of the underground low-temperature storage tank to improve the entire underground low-temperature storage tank. It is an object of the present invention to provide a method of constructing a roof of an underground low-temperature storage tank that has achieved a shortened construction period.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a dome-shaped roof construction method which is attached to an upper opening of a bottomed cylindrical tank body. The horizontal bone is bridged between a pair of vertical bone frames curved in the same direction to form a substantially fan-shaped divided bone frame, a roof plate is stretched on the upper surface of the divided bone frame, and a cold insulator is provided on the lower surface thereof. After forming a plurality of divided roof units in a substantially fan shape in parallel with or before the construction of the tank body, these divided roof units are carried into the bottom of the inside of the tank body, and the divided roof units are divided in the inside of the tank body. The units are sequentially joined in the width direction to form a dome-shaped roof portion, and then the roof portion is raised by air lasing or jack-up, and is installed on the upper opening side of the tank body. According to the method of the present invention, as described above, the dome-shaped roof portion installed on the upper portion of the tank body is constituted by a plurality of split roof units including a split bone frame, a roof plate, and a cold insulator, and the split roof unit is formed in the tank body. And installed in the upper opening of the tank body.

Therefore, by forming this split roof unit in parallel with or before the construction of the tank body, the roof construction work inside the tank body, after assembling the split roof unit in the tank body, rises in the tank body. Then, since it is only installed in the upper opening, the construction period required for roof construction is greatly reduced.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the construction method of the roof part 4 of the underground low-temperature storage tank according to the present invention is performed in advance in a factory or the like on the bottom plate 2 in the underground low-temperature storage tank 1 for storing low-temperature liquid such as LNG. After the manufactured plurality of divided roof units 3 are carried in and the plurality of divided roof units 3 carried on the bottom plate 2 are joined to construct a circular dome-shaped roof portion 4, the roof portion 4 is air-raised or It is raised by jack-up and connected and fixed to a knuckle plate 5 provided at the upper edge of the tank body of the underground cold storage tank 1.

The roof 4 is for sealingly covering the upper opening of the cylindrical underground cold storage tank, and extends radially and radially from a cylindrical central block 16 provided on the roof top. A plurality of divided roof units 3 constituting the vertical bone A and the horizontal bone B are joined together in a circular dome shape. Further, temporary roof receiving posts having different lengths are provided at a lower portion of the roof portion 4 to support each of the divided roof units 3 when assembling the roof portion 4 from the divided roof units 3.
A plurality of 11, 12, and 13 are provided.

As shown in FIG. 1, the divided roof unit 3 first forms a vertical frame 6 in a fan shape so as to divide the vertical bone A constituting the roof portion 4 into a predetermined length. A horizontal bone 7 for supporting the vertical frame 6 is spanned between the fitted vertical frames 6 to form a divided bone frame 8, and a roof panel 9 is stretched on the outside of the divided bone frame 8. The heat insulating material 10 for blocking external heat input is stretched over the base material.

Particularly, the vertical frame 6 of the fan-shaped split roof unit 3 is formed of a C-shaped groove steel as shown in the figure. Therefore, when connecting the divided roof units 3 adjacent to each other, connection by welding or the like is facilitated.

The vertical frames 6 of the adjacent split roof units 3 are connected by a connecting plate 15 as shown in FIGS.

One end of the connection plate 15 is welded to a part of the vertical frame 6 constituting a side of the split roof unit 3 at a predetermined interval. The other end of the connecting plate 15 is fitted into a downwardly tapered projection 20 in the vertical frame 6 of another split roof unit 3 to be joined. The vertical plate frames 6 can be joined together by fitting the connecting plate 15 into the connector. In addition, connection bolt holes 17 are formed on both front and rear sides of the connection plate 15 and the projection 20.By fastening the connection bolt 19 through the connection bolt 19 on the front and rear sides of the projection 20 and the connection plate 15, The entire split roof unit 3 is gradually crimped.

In addition, the connecting plate 15 and the connecting plate
15 is connected by welding.

 Next, the method of the present invention will be described.

First, as shown in FIG. 2, the divided roof unit 3 and the central block 10 and the like previously manufactured in a factory or the like are loaded onto the bottom plate 2 in the underground low-temperature storage tank 1, and the central block 16
Is mounted on the temporary roof support column 11 prepared in advance.

Next, as shown in FIG. 3, each divided roof unit 3 is circumferentially arranged so as to form a circle around a central block 10 mounted on the roof support column 11, and the roof support columns 11,1 are arranged.
2 to form an inner peripheral portion. Further, the divided roof units 3 are further arranged on the outer periphery in the circumferential direction and mounted on the roof support columns 12 and 13 to form the outer periphery.

At this time, the divided roof units 3 arranged in the circumferential direction and the radial direction connect the butting longitudinal frames 6 to each other by a plurality of connecting plates 15 as shown in FIGS. The part without the mark will be connected by welding.
Similarly, the roof shingles 9 that abut each other by connecting the divided roof units 3 are integrally connected by welding from above.

When the roof portion 4 is formed in a circular dome shape in this manner, as shown in FIG.
The roof 10 is also integrated in the same manner as the roof slab 9, and the roof 4 is completed.

Next, the roof part 4 completed on the floor plate 2 is raised in the tank 1 by air-raising or jack-up,
As shown in FIG. 5, it is connected and fixed to a knuckle plate 5 provided on the upper edge of the tank body of the tank 1 by welding or the like. At this time, there is a slight gap between the roof plate 9 of each split roof unit 3 and the knuckle plate 5, but this gap is closed by the adjustment plate 14 so that the roof plate 9 and the knuckle plate 5 are integrated. To be connected.

 Next, another modified embodiment will be described.

In this embodiment, as shown in FIG. 7, by changing the size of the split roof unit 3 constituting the above-described roof portion 4a, the stress applied to the connecting portion when the split roof units 3 are combined is dispersed. It was made.

That is, as shown in FIG.
Is set to the same size, the joints become cross-shaped, and the stress on the roof 4 due to vibrations and pressure changes concentrates on the cross-shaped joints with low strength, and the roof 4
This prevents the overall durability from lowering.

As shown in the figure, the roof portion 4a is formed in a substantially trapezoidal shape, and is configured by combining divided roof units 3 having different widths and lengths.

By configuring in this manner, the joints of each of the divided roof units 3 can all be T-shaped, and a cross-shaped joint whose strength is likely to be reduced can be avoided.

[Effect of the Invention] The roof part of the underground cold storage tank is composed of a plurality of divided roof units, and this divided roof unit is formed in parallel with the construction of the tank body or before the construction of the tank body. The construction period of the roof can be greatly reduced. As a result, there is an excellent effect that the demand of the consumer can be satisfied and labor cost can be saved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the entire structure of the split roof unit 3,
FIG. 2 is a side view showing a state in which a circular dome-shaped roof is constructed from the divided roof units 3 on the floorboard, FIG. 3 is an enlarged sectional view showing a connecting portion of the divided roof units 3, and FIG. The side view of FIG. 3 and the roof of FIG.
Partial perspective view showing a state connected to a knuckle plate,
FIG. 6 is a sectional view taken along line AA of FIG. 5, and FIG. 7 is a sectional view taken along line B- of FIG.
FIG. 8 is a partial plan view of a roof portion showing another modified embodiment, and FIG. 9 is a side view showing a construction state of a conventional roof portion. In the figure, 1 is an underground low-temperature storage tank, 2 is a floor plate, 3 is a split roof unit, 4 is a roof, 6 is an osteotomy frame, 7 is a lateral bone, 8 is a split bone frame, 9 is a roof plate, and 10 is a cooling material. , A
Is a vertical bone.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) F17C 3/00, 3/04 F17C 13/08 E04H 7/18

Claims (1)

(57) [Claims] 1. A method of constructing a dome-shaped roof portion to be attached to an upper opening of a tank having a bottomed cylindrical shape, wherein a horizontal space is provided between a pair of vertical bone frames located in a C-shape and curved in the same direction. Bridge the bones to form a roughly fan-shaped split bone frame,
After a roof plate is stretched on the upper surface of the divided bone frame and a cooling material is stretched on the lower surface side thereof, a plurality of substantially roof-shaped divided roof units are formed in parallel with or before the construction of the tank body. Then, these divided roof units are carried into the bottom of the tank body, and the divided roof units are sequentially connected in the width direction in the tank body to form a dome-shaped roof portion.
A roof part construction method for an underground low-temperature liquid storage tank, wherein the roof part is raised by air-raising or jack-up, and is installed on the upper opening side of the tank body.