JPH0362960B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology belongs to the technical field of the structure of concrete cylindrical walls with liners for concrete cylindrical tanks, and is a low-temperature double tank for storing low-temperature liquefied gases such as LNG and LPG. Concrete outer tank of shell tank, or
It belongs to the technical field of high dike or concrete single-shell tank structure.

<Explanation of the gist> The present invention provides a low-temperature double-shell tank that is installed on a predetermined foundation and has an outer tank made of concrete with a cold insulating material interposed between the inner tank and the inner tank. This invention relates to a double-shell cylindrical concrete tank having an outer tank concrete wall or a concrete dike (sometimes a cylindrical high dike placed in the immediate vicinity of the tank) for secondary storage of stored liquid in the event of a disaster. ,especially,
The thickness of the cylindrical wall concrete is thinner than that of conventional cylindrical wall concrete, and the cylindrical wall is composed of a concrete outer tank side wall body and a metal liner attached to the inner surface thereof via a dowel or the like. Furthermore, the latter is a double-shelled cylinder with a stiffener integrally fixed on its inner surface to support lateral loads such as those caused by earthquakes, and with a cold insulating material interposed between it and the inner tank. This invention relates to a concrete tank.

<Prior art> As is well known, in recent years, due to changes in the energy situation, the capacity of both service tanks and storage tanks has gradually increased.
Even in the case of low-temperature double-shell tanks for storing low-temperature liquefied gases such as LNG and LPG, the construction of tanks with larger capacities has begun to be designed.

Furthermore, for this type of large storage tank, concrete structures are increasingly being introduced from the standpoint of disaster prevention and unexpected accidents.

Traditionally, single-shell tanks such as water tanks have often been made of concrete, but in recent years, LNG and
In low-temperature double-shell tanks for LPG storage, etc., there is a strong tendency to form the outer tank side walls with concrete for disaster prevention reasons such as nearby fires, earthquakes, unexpected accidents, etc., or from the viewpoint of appearance, and for similar reasons. Concrete structures are also becoming more common, with a cylindrical structure in which a high dike is installed close to the tank.

As an example, a conventional low-temperature double-shell cylindrical concrete tank will be briefly explained with reference to FIG. A concrete outer tank 4 having a liner 10 is erected through 9..., and a bottom cold insulating material 5 and
An inner tank 7 made of low-temperature steel is provided via a side cold insulator 6, and a low-temperature liquefied gas 8 such as LNG or LPG is placed in the inner tank 7.
It is designed to store and receive and operate at designated times.

<Problems to be Solved by the Invention> As mentioned above, these concrete cylindrical tanks have recently become large in size, so they are not only subject to specification limitations due to internal pressure conditions, but also to earthquake loads, wind loads, etc. The lateral load of the tank is also large, and the concrete cylindrical wall has to be enlarged in order to sufficiently withstand this load and support the tank body. For example, in the case of the embodiment shown in Fig. 1, storage capacity
A 40,000 ton LPG tank is generally designed with an outer tank 4 made of 2m thick RC or 1m thick PC concrete.

Not only is the thickness large in terms of strength calculations, but it is also multiplied by a safety factor of 30%, making it even thicker.

Therefore, the thickness and weight of the outer tank 4 made of concrete becomes large, and the amount of concrete used and the amount of reinforcing also become large.As a result, there is a disadvantage that costs increase, and the construction time at the time of construction is increased. Another problem was that the process was long, the amount of work was large, and the construction work was extremely cumbersome.

Furthermore, as the concrete outer tank 4 becomes larger and heavier, the specifications of the foundation 3 also become larger and its structure becomes more complex.

<Objective of the Invention> The object of the present invention is to solve the problem of the concrete cylindrical wall of a double-shell tank such as a low-temperature double-shell tank based on the above-mentioned prior art, and to solve the problem of the external environment of the cylindrical wall. By separating the isolation function and storage fluid retention function from the support function for lateral loads such as wind loads and earthquake loads, we are able to take full advantage of the advantages of concrete, while also making full use of these functions. , an excellent double-shell cylinder that is beneficial to the field of storage technology application in the energy industry by reducing the weight of the tank and simplifying the basic specifications, as well as shortening the construction time and reducing costs. The project aims to provide concrete tanks.

<Means/effects for solving the problem> In order to solve the above-mentioned problem, the structure of the present invention, which is based on the scope of the above-mentioned claims, is based on the thickness of the foundation provided on a predetermined ground. A concrete cylindrical wall with a reduced amount of reinforcement is made as thin as possible to the thickness required by internal pressure conditions, etc., or to a thickness close to that thickness, and is made into the main body of the cylindrical side wall of the outer tank. A metal liner is integrally attached to the side surface of the metal liner via a dowel or the like, and a stiffener is integrally welded around the side surface of the metal liner to increase its strength and rigidity. The concrete outer tank wall body maintains internal pressure and isolates the tank from the external environment, and the metal liner and stiffener provide sufficient protection against wind loads and lateral loads such as earthquakes. This technology reduces the weight of the cylindrical wall as a whole, thereby making it lighter, simplifying the basic specifications, and shortening the construction period and reducing costs. The measures taken were as follows.

<Example> Next, an example of the present invention will be described with reference to FIG.
The explanation will be as follows based on FIG.

Note that the same parts as in FIG. 1 will be explained using the same reference numerals.

1' is a double shell cylindrical concrete tank for low temperature storage which constitutes the gist of this invention; for example,
It stores and receives and receives low-temperature liquefied gas 8 such as LNG and LPG, and on the foundation 3' formed on a predetermined ground 2 is an outer tank side wall made of concrete such as RC or PC. The main body 4' is erected in a cylindrical shape, and its thickness is thinner than that of the conventional low-temperature double shell tank 1 shown in FIG.
It can be made as thin as ~300mm, so the amount of RC or PC concrete used and the amount of reinforcement are quite small, and there is no need to increase the safety factor of 30% like in the past. , so its weight is sufficiently small.

When forming the outer tank side wall body 4', well-known dowels 9', 9', . . . are fixed to the inside of the RC or PC.

In the illustrated embodiment, the outer tank body
A predetermined metal liner 10' is integrally attached and fixed to the inner surface of 4' via dowels 9', 9', . . . .

In addition, suitably designed stiffeners (wind garters) 11, 11, etc. are welded and fixed to the inner surface of the metal liner 10', and the outer tank side wall made of concrete is attached via the metal liner 10' and the dowel 9'. The main body 4' is connected to the main body 4', thereby increasing the rigidity of the entire side wall of the outer tank.

Therefore, the concrete outer tank side wall body 4' and the metal liner 10' maintain the internal pressure of the tank due to their airtightness and internal pressure resistance, and
It has a sufficient sealing function to block outside air, and since the stiffener 11 is connected to the metal liner 10' and the concrete outer tank side wall main body 4', it is able to withstand lateral loads such as wind loads and earthquake loads. It will be formed to have great strength and rigidity.

A bottom cold insulating material 5 is laid on the bottom plate of the outer tank on the foundation 3', and a side cold insulating material 6 is provided inside the metal liner 10'. A low-temperature double shell tank 1' is constructed by forming an inner tank 7', a side cold insulating material 6 is filled between the inner tank 7' and a metal liner 10', and an outer tank roof is provided. , LNG in 7 inner tanks,
A low-temperature liquefied gas 8 such as LPG is stored and operated at a predetermined time.

In the above configuration, the concrete outer tank side wall body 4' and the metal liner 10' of the low temperature double shell tank 1' maintain the sealing pressure and vertical load in the outer tank side wall body 4', At the same time, the outside environment and the inside of the tank are shut off, and the low-temperature liquefied gas 8 is received and discharged in a predetermined manner in this state.

Therefore, the stiffeners 11, 11..., metal liner 10', and concrete outer tank side wall body 4' work together to provide high rigidity against lateral loads such as wind loads and earthquake loads during operation. Therefore, although the thickness of the concrete outer tank side wall main body 4' is thinner than the conventional concrete wall, it can sufficiently counter the damage, and the function of the double shell tank 1' will not be impaired in any way. There is no.

It goes without saying that the embodiments of the present invention are not limited to the above embodiments. For example, a metal liner may be attached to the outer surface of the concrete outer tank side wall body, and a stiffener may be attached to the outer surface of the metal liner. Various aspects can be adopted, such as providing a

<Effects of the Invention> According to the present invention, in a large double-shelled cylindrical concrete tank, a stiffener is attached to the metal liner on the side surface of the main body of the concrete outer tank side wall, thereby increasing the strength of the entire cylindrical wall against lateral loads. Because the rigidity can be increased, the concrete specifications for the cylindrical wall do not have to be large-scale, the amount of concrete used is small, and the amount of reinforcement is also small.
Moreover, there is no need to increase the concrete thickness to increase the safety factor as in the conventional method.
Therefore, the construction period can be shortened, and there is an effect that it is possible to reduce the amount of materials used and costs.

Also, since the weight of the cylindrical wall is reduced, the foundation specifications that support it are not as large-scale as a result.
Naturally, the foundation work period is short, which has the advantage of shortening the overall construction time and lowering construction costs.

Furthermore, since a metal liner with a stiffener is attached to the side of the concrete cylindrical wall, the construction may become more extensive, but the overall cost and construction period can be reduced. effective.

[Brief explanation of drawings]

FIG. 1 is a partial half-sectional view of a low-temperature double-shell tank based on the prior art, and FIG. 2 is a partial half-sectional view of one embodiment of the present invention. 3'...Foundation, 7'...Inner tank, 1'...Low temperature double shell tank, 4'...Outer tank side wall body, 10'...Metal liner, 11...Stiffener, 5, 6...Cold storage Material.

Claims (1)

[Claims] 1. In a double-shell cylindrical concrete tank installed on a foundation, the cylindrical wall consists of a concrete outer tank side wall body and a metal liner attached to the side of the concrete outer tank side wall body, and A double shell cylindrical concrete characterized in that the metal liner has a number of stiffeners integrally fixed to its inner surface, and further a cold insulating material is interposed between the metal liner and an inner tank inside the metal liner. tank.