JPH0335469B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a construction method for an underground low-temperature storage tank,
In particular, the present invention relates to a construction method for an underground low-temperature storage tank that improves the construction method for the upper part of the storage tank side wall.

[Conventional technology]

Underground low-temperature storage tanks generally have a structure in which most of the lower part of the tank is built underground, and the upper part of the side walls and roof of the tank are exposed to the ground surface, making them intimidating to nearby residents and the surrounding environment. Consideration has been given to reducing the impact of perceived and visible pollution.

In a conventional low-temperature storage tank, a roof aggregate is welded to an anchor member buried in the upper end of an upright side wall, and a roof is stretched over the roof aggregate to form a storage tank.

[Problem that the invention seeks to solve]

In the case of the above-mentioned conventional underground low temperature storage tank, the roof is the same size as the upper opening of the storage tank formed by the upright side walls, so the roof that appears above the ground is large and still gives an intimidating feeling. Additionally, when an earthquake occurs, the low-temperature liquid inside oscillates, causing sloshing, in which the liquid level oscillates in a straight-arc wave pattern due to its own periodicity, which adversely affects the floating roof and tank.

In order to solve the above-mentioned visibility problems and problems with sloshing in conventional underground low-temperature storage tanks, this invention reduces the size of the roof portion that appears on the ground surface and effectively attenuates fluctuations in the liquid level due to sloshing. The object of the present invention is to provide a method for constructing an underground low-temperature storage tank, which allows easy construction of a low-temperature storage tank with a structure that is superior in terms of reinforcing properties and strength.

[Means for Solving the Problem] In order to achieve the above object, the present invention embeds an anchor member in advance in the upper part of the upright side wall of a cryogenic storage tank, and inserts an inwardly curved segment in the anchor member into the upright side wall. It is attached to the upper part of the side wall as an inner formwork for constructing an upper curved wall of the side wall that curves inward, and a temporary formwork is temporarily installed on the outside, concrete is poured between these, and this concrete and the segment are It is characterized by constructing a curved wall at the upper part of the side wall with a narrowed upper opening, and constructing a roof on top of the curved wall.

[Effect]

Since the upper part of the side wall is narrowed by the curved wall,
It is possible to easily construct a low-temperature storage tank that reduces the size of the roof that appears on the ground surface, effectively attenuates sloshing on the inner surface of the curved wall, and has excellent reinforcing properties and strength.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a vertical cross section of an example of an underground low temperature storage tank constructed by the construction method of the present invention, in which a side wall upper curved wall 3 is formed at the upper end of an upright side wall 2 of the storage tank 1, and a portion of the upright side wall 2 is shown in FIG. is buried underground, the outer surface of the curved wall 3 is covered with embankment 4, and only the roof 5 is exposed on the ground surface. 6 indicates the low temperature liquid in the storage tank 1.

The segment 7 used in the construction method of the present invention has an arc shape that matches the curvature of the circumference of the storage tank 1 as shown in FIG. A skin plate 9 made of iron plate such as SS material and having a thickness of about 2 m/m is stretched over the entire surface of the skin plate 8, and a foam material is laminated on the skin plate 9 in a slightly smaller area. A cold insulating material layer 10 consisting of
and a membrane 11 attached to the surface of the cold insulating material layer 10, and bolts 12 for connecting adjacent segments are buried at required positions at the ends of the concrete layer 8. A recessed portion 13 is formed.

As shown in FIG. 3, the segment 7 formed in this manner is fixed to an anchor member 14 that is installed inside the upper end of the upright side wall 2 and buried in the upper end of the upright side wall 2 in advance, so that the segment 7 adjacent to the segment 7 are sequentially connected by bolts 12 and nuts 15, and are connected over the entire circumference of the upper end of the upright side wall 2. As a result, the upper end of the upright side wall 2 is narrowed into a curved shape toward the inside of the storage tank 1 by each segment 7, and this is used as an inner formwork for forming the curved wall 3. Note that the segments 7 are stacked in one or more stages depending on the degree of narrowing of the upper end opening portion of the storage tank 1.

On the other hand, an outer formwork 18 is provided outside the upper end of the upright side wall 2.
is temporarily constructed, and this outer formwork 18 and the segment 7
Concrete and 19 are placed between the curved wall 3
is constructed. In this case, at the upper end of the curved wall 3,
An anchor member 20 for connecting roofing material is buried.

Parallel to the pouring of the concrete 19 of this curved wall 3, or after curing of the concrete 19, a segment 7 for constructing an inner tank in which low temperature liquid is stored.
It is necessary to connect the membranes 11 provided on the surfaces of the tubes, and a corrugation 16 as shown in FIG. 4 is used. This corrugation 16
is made of a low-temperature-resistant thin metal plate and is placed along the inner surface of the vertical joint of the segment 7, and includes a segment abutting portion 16a that follows the concave curved inner surface shape of the joint of the segment 7; It consists of a bent part 16b extending from the upper end of the segment 7 to the upper end of the upright side wall 2 so as to wrap around the upper end.
A convex ridge 16c is provided which is formed in an omega-shaped sliding bulge. This corrugation 16 is placed across the joint of the segment 7 as shown in FIG.
The space formed by the end face is filled with a regular or irregularly shaped cold insulating material 17, and the bolts 12 and nuts 15 are also hidden by this cold insulating material 17.

Further, the lateral joints of the membranes 11 of the segments 7 are connected by low-temperature-resistant flat metal thin plates.

Furthermore, after the concrete 19 of the curved mold 3 is cured, the outer frame 18 is removed, and the anchor member 20 at the upper end thereof is removed.
As shown in Figure 6, a roof frame 21 made of shaped steel etc.
are welded and a roof plate 22 is stretched thereon, and a cold insulation material 23 is stretched on the inner surface to construct a roof 5. In this case, the cold insulation material 23 is connected to the corrugation 16.
so as to cover up to the bent portion 16b. The outside of the curved wall 3 is covered with embankment 4.

The cryogenic storage tank 1 thus completed has a configuration in which the upper end of the upright side wall 2 is narrowed, as shown in FIG. The size of the curved wall 3 becomes significantly smaller, and the apparent size of the part that appears on the other side becomes smaller, reducing the intimidating appearance, and even if the low-temperature liquid in the low-temperature storage tank is shaken by an earthquake, the inner surface of the curved wall 3 will not tilt downward. Since it is curved so as to face the opposite direction, vibration waves are well attenuated and this contributes to countermeasures against sloshing.

(Effects of the Invention) As described in detail above, in the present invention, an anchor member is buried in advance in the upper part of the upright side wall of a low temperature storage tank, and a segment concave inwardly is inserted into the anchor member at the upper part of the upright side wall. The upper part of the side wall that curves inward is installed as an inner formwork for constructing a curved wall, and a temporary formwork is temporarily installed on the outside and concrete is poured between them, and the upper opening is narrowed by this concrete and the segment. Since the underground cryogenic storage tank is constructed by constructing a curved wall at the upper part of the side wall and constructing a roof on top of it, the resulting cryogenic storage tank has a form in which the area of the upper part that appears above the ground is small. As a result, the feeling of intimidation can be reduced and visible pollution can be eliminated, as well as having the effect of damping the agitation of the low-temperature liquid inside. When constructing a low-temperature storage tank with such effects,
In this invention, concrete is poured using segments that have been produced to a standard in a factory or the like as the inner formwork of a curved wall, which is difficult to construct, and these segments are made into a part of the curved wall, so that they cannot be removed after being poured. Construction is extremely easy as it is unnecessary, and since the segments function as reinforcing materials even after concrete is poured, the greater the strength of the area, the better the construction and structure of the low temperature storage tank after completion. effective.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view showing an example of a low temperature storage tank constructed by the construction method of the present invention, Fig. 2 is a perspective view of the segment used in the construction method of the invention, seen from the inner side, and Fig. 3 is the same as that shown in Fig. 1. FIG. 4 is a perspective view of the corrugation, FIG. 5 is a sectional view taken along the line A-A in FIG. FIG. 7 is a partial sectional view showing the construction process of the joint, a front view seen from the inside, and FIG. 8 is an enlarged sectional view taken along the line B--B in FIG. 7. 1... Low temperature storage tank, 2... Upright side wall, 3... Side wall upper curved wall, 4... Embankment, 5... Roof, 6... Low temperature liquid, 7... Segment, 8... Concrete layer, 9... Skin plate, 10...cold material layer,
11...membrane, 12...bolt, 13...
Recessed portion, 14...Anchor member for fixing segment, 1
5...Natsuto, 16...Corrugation, 17,
23...Cold insulation material, 18...Outer formwork, 20...Anchor member for connecting roofing material, 21...Roof frame, 22...
roof shingles.

Claims (1)

[Claims] 1 An anchor member is buried in advance in the upper part of the upright side wall of the low temperature storage tank, and an inwardly curved segment is installed in the anchor member as an inner formwork for constructing an upper curved wall of the side wall that curves inwardly in the upper part of the upright side wall. Installation: Temporary formwork is temporarily installed on the outside, concrete is poured between them, and a side wall with a narrowed upper opening is constructed using this concrete and the segments, and a curved wall at the top of the side wall is constructed. A construction method for an underground low temperature storage tank characterized by constructing a roof.