JPS6122104B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of constructing cylindrical steel structures such as silos.

Cylindrical steel structures such as steel silos generally have a block structure in which circumferential rings (side plate rings) are stacked in several stages. The method used is to stack the stacks one by one using a crane or the like and weld the welded joints of each stack each time. However, with this construction method, as the circumferential rings are piled up, the work areas such as welding become progressively higher, which requires higher scaffolding, and there are problems such as reduced work efficiency and safety due to high-altitude work. Naturally, such problems have a large impact on construction costs.

The present invention was devised in view of the lack of such conventional methods, and it is possible to weld and join each circumferential ring without involving work at heights in constructing a cylindrical steel structure using circumferential rings. The purpose is to provide a construction method that can be used.

Therefore, when a plurality of circumferential rings are piled up and welded together, the present invention provides a block consisting of two or more welded circumferential rings, which is stacked on top of another circumferential ring and then welded together. A block consisting of a plurality of circumferential rings is formed by repeating the process of stacking the joined blocks on another circumferential ring and welding and joining them according to the number of circumferential rings to be joined. By doing this, welding of circumferential rings can always be performed between one circumferential ring and a block consisting of a plurality of welded circumferential rings stacked on top of it, and it is possible to avoid the need for high places during construction. The work can be avoided.

Figures 1A to 1D show the basic configuration of the present invention.According to this, two workplaces are prepared for assembling the peripheral ring block, and first, as shown in Figure 1A, the peripheral ring block is assembled in workshop A. Stack peripheral ring A ₂ on top of body ring A ₁ and weld them together to form block M _1.
to form. During this time, a circumferential ring was placed in work area B.
Have a ₃ ready. Next, this joined block _M1 is lifted up and carried to the workshop B by a crane or the like, stacked on the circumferential ring _a3 , and welded and joined to form the block _M2 . Furthermore, a block M ₂ consisting of three circumferential rings from workshop B is stacked on circumferential ring a ₄ prepared in workshop A and welded together to form four circumferential rings a ₁ , a ₂ , a ₃ ,
Block _M3 consisting of _a4 is formed. Then, by repeating the above cycle according to the number of circumferential rings a to be joined, a block consisting of an arbitrary number of circumferential rings is formed. Then, the block M obtained by joining a plurality of circumferential rings a is finally transported to a construction site by a crane or the like, and is fixed to the base there. Therefore, in the above-mentioned work, the welding work of the circumferential ring a is performed between _a1 and _a2 , between _M1 and _a3 , and between _M2 and _a4 , and therefore, the work is always The welding is carried out at the height of the upper edge of the lowermost circumferential ring a, so there is no need to perform high-altitude welding as in the past. It is possible to stack any number of circumferential rings within the range of its abilities to create a block.

Figures 2A to 2E show an embodiment in which the present invention is applied to the construction of a silo. In this embodiment, a silo is constructed by stacking four circumferential rings b ₁ to b ₄ .According to this, circumferential rings b ₁ and b ₂ are first prepared in workshop A and workshop B, respectively. . Dropping fittings 1 are attached to the circumferential rings b at a plurality of positions in the circumferential direction at the bottom thereof, and in this embodiment, the dropping fittings 1 also serve as hanging fittings for the circumferential rings. In addition, each circumferential ring b is placed on a support stand 2 in order to prevent the drop-in fitting 1 protruding from its lower end from touching the ground and to allow a worker to enter the circumferential ring b from below. There is.

From this state, first, the circumferential ring b ₂ in the workshop b is lifted up by a crane (not shown) and stacked on the circumferential ring b ₁ in the workshop A, as shown in FIG. 2A. The circumferential ring b ₂ is lifted up by attaching a lifting wire 3 to each drop-in fitting 1, and the circumferential ring b ₂ thus lifted is attached to a drop-in fitting protruding from its lower end. 1 is stacked on the circumferential ring b ₁ by dropping it inside the upper end of the circumferential ring b ₁ .

In this state, the inner periphery of the abutting part between the circumferential rings b ₁ and b ₂ is welded together, but for this reason, the circumferential rings
A temporary scaffold 4 for welding work, which should be located inside the circumferential ring b _{1, is provided in advance at the part where b 1 is} placed, and the above-mentioned welding is performed by a worker on the temporary scaffold 4. . After the welding is completed, the drop-in fitting 1 is cut and removed by an operator.

During or after such work, another circumferential ring _b3 is prepared in the work place B. This circumferential ring
b ₃ also has a drop-in fitting 1 at its lower part, and a support stand 2
A temporary scaffolding 4 is placed on top of it, and a temporary scaffolding 4 is provided inside it.

The block N ₁ consisting of the joined circumferential ring b ₁ and circumferential ring b ₂ is lifted up again by a crane, and the circumferential ring is placed in the workshop B as shown in Fig. 2 (c).
b Stacked on top of ₃ . Then, in this state, a worker performs welding work on the temporary scaffolding 4, and a block _N2 consisting of circumferential rings _b1 , _b2, and _b3 is formed. After this welding and joining, the drop-in fitting ₁ of the circumferential ring b1 is welded and cut.

Such block _N2 is further hoisted by a crane and stacked on the newly prepared circumferential ring _b4 in the workshop A, as shown in Fig.
A block _N3 is formed consisting of b ₁ , b ₂ , b ₃ and b ₄ . When the assembly of the circumferential ring b is completed in this way, the block _N3 is transported by a crane to the construction site C, as shown in FIG. Pile up. In this case as well, the dropping metal fitting 1 of the circumferential ring _b4 is used for dropping, and the inner periphery welding is performed by a worker inside the hopper block 6.

As described above, according to the method of the present invention, the welding of the circumferential rings b can always be performed at the height of the upper edge of one circumferential ring b, and therefore welding work at high places can be avoided.

Furthermore, silo construction using the method of the present invention is as follows:
In the end, the block _N3 , in which circumferential rings b are stacked in multiple stages, is lifted and transported to the construction site by a crane, so it goes without saying that the number of stacked stages depends on the capacity of the crane.

In this embodiment, when lifting the block N (or the single circumferential ring b), the drop-in fitting 1 is used, but the lifting method shown in Figs. 2 and 3 is used. is taken. That is, for this lifting, a lifting body 7 having a plurality of wire attachment parts 8 corresponding to the drop-in fittings 1 is used.
Each wire attachment part 8 of this suspension body 7 and each drop-in fitting 1 of the peripheral ring b at the bottom of the block N are connected by a wire 3, and the suspension body 7 is lifted by a crane. do. In this embodiment, the hanging body 7 is composed of a cross-shaped frame body, and has wire attachment portions 8 at the tips of each side 71 of the cross shape.
A wire 3 is connected to the terminal. The length of one side 71 of the cross shape of this suspension holder 7 approximately corresponds to the inner radius of the block N, or is configured to be slightly smaller, so that the suspension holder 7 is positioned inside the upper part of the block N when it is lifted. The tip of each side 71 is brought close to (or in contact with) the upper inner circumferential surface of the block N, thereby appropriately preventing the block N from shaking during lifting. Note that the structure of the suspension body 7 is not limited to the above embodiment, and has a plurality of wire attachment portions, and is close to the inner circumferential surface of the block N (or Any suitable structure can be used as long as it can make contact (contact). Therefore, in this embodiment, as mentioned above, the wire 3 is connected to the bottom of the block N for lifting, so the lifting allowance can be kept small, and moreover, the block The wire 3 can also be easily removed at a low location (temporary scaffolding).

According to the present invention described above, when forming a block by stacking and welding a plurality of circumferential rings, it is possible to always perform the welding and joining work at the position of the lowest circumferential ring, which eliminates the need for high scaffolding. There is no need to install it, and it appropriately avoids the problems of reduced work efficiency and reduced safety due to work at heights.
It has the excellent feature of allowing work to be done efficiently and safely.

[Brief explanation of the drawing]

FIGS. 1A to 1D are explanatory diagrams showing the basic structure of the method of the present invention in the order of steps. FIGS. 2A to 2E are explanatory views showing, in order of steps, an embodiment in which the method of the present invention is applied to the construction of a silo. FIG. 3 is an explanatory diagram showing a method of lifting blocks. In the figure, a ₁ , a ₂ , a ₃ , a ₄ , b, b ₁ , b ₂ ,
b ₃ , b ₄ are peripheral blocks, M ₁ , M ₂ , M ₃ , N, N ₁ ,
N ₂ and N ₃ indicate blocks.

Claims (1)

[Claims] 1. When stacking and welding a plurality of circumferential rings, a block consisting of two or more welded circumferential rings is stacked and welded on top of another circumferential ring, and then the block resulting from such welding is Furthermore, by repeating the process of stacking and welding the circumferential rings on top of another circumferential ring according to the number of circumferential rings to be joined, a block consisting of a plurality of circumferential rings is formed. How to build steel structures.