JP2001182376A - Steel tower supporting type chimney and its construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further reduce construction time and cost, and improve workability without spoiling strength against wind or earthquakes. SOLUTION: A cylindrical body 3 is erected upright inside of a steel tower 2 to support the cylindrical body 3 by the steel tower 2. The horizontal external sectional form of the steel tower 2 is shaped to be substantially equal at any position in the height direction, and further, the steel tower 2 is constituted of blocks 7 having the same shape with a plurality of vertically divided blocks. Furthermore, the cylindrical body 3 is hung in the steel tower 2 and supported thereby. Oil dampers 13 are interposed between the top of the steel tower 2 and the cylindrical body 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tower-supporting chimney in which a tubular body is supported auxiliary or directly by a tower, and a method of constructing the same.

[0002]

2. Description of the Related Art One type of chimney includes a structure in which a tubular body is built upright inside a steel tower, and the tubular body is supported from the side by the steel tower. For such a tower-supported chimney, see JP-B-54-39149, JP-B-8-14212.
No. 6,019,064, and discloses that the device has an advantage that it is resistant to wind and earthquake and can be constructed relatively inexpensively.

[0003]

The construction of such a so-called tower-supported chimney has been reduced while improving its resistance to wind and earthquakes. Reduction has come to be desired.

The present invention has been made in view of the above circumstances, and has as its object to further reduce the construction cost, shorten the construction period, and improve the workability without impairing the resistance to wind and earthquake.

[0005]

As means for solving the above-mentioned problems, a tower-supporting-type chimney having the following structure and a construction method thereof are employed. In other words, the tower supporting chimney according to claim 1 is a tower supporting chimney in which a tubular body is built upright inside a tower and the tubular body is supported by the tower, wherein the steel tower has a horizontal cross-sectional shape. Are substantially equal at any point in the height direction and are constituted by a plurality of blocks of the same shape divided in the height direction.

In this tower-supporting chimney, the tower is divided into blocks of the same shape, and the tower is constructed by assembling the blocks on the foundation, thereby making it possible to standardize the members constituting the tower. The production cost of the block body is reduced, and the construction cost of the tower itself is reduced.

According to a second aspect of the present invention, there is provided a tower supporting type chimney according to the first aspect, wherein the tubular body is suspended by connecting a lower end thereof to the tower via a suspending member. It is characterized by.

In this tower-supporting chimney, since the tubular body is suspended from and supported by the steel tower, the steel tower receives the pulling force generated when the tubular body receives a lateral force. Since it stands on the foundation outside the body and has higher stability than the barrel, it can sufficiently withstand the pull-out force caused by the tubular body receiving a lateral force. Also, when the cylinder is rigidly fixed on the foundation, a large bending moment acts near the foundation of the cylinder, but by suspending and supporting the cylinder, this bending moment can be significantly reduced. Will be able to

According to a third aspect of the present invention, there is provided a tower-supporting chimney according to the second aspect, wherein a wall thickness of a side wall of the tubular body located below a top of the tower is equal to a top of the tower. Characterized in that it is formed to be thinner than the wall thickness.

In this tower-supported chimney, since the tubular body is suspended and supported by the steel tower, the bending moment acting on the vicinity of the base of the tubular body is significantly greater than when the tubular body is rigidly fixed to the foundation. Become smaller. This makes it possible to reduce the thickness of the side wall of the cylindrical body located below to a thickness that exhibits sufficient strength against bending, thereby reducing the construction cost of the cylindrical body.

According to a fourth aspect of the present invention, there is provided a tower supporting type chimney according to the first to third aspects, wherein a damper is interposed between the top of the tower and the tubular body. Features.

The cylinder vibrates when subjected to a lateral force, causing a relative displacement between the top of the tower and the cylinder. Therefore, a damper is interposed between the top of the tower and the tubular body, and when a relative displacement occurs between the top of the tower and the tubular body, this is activated to attenuate the vibration. In this tower-supporting chimney, the damping of the cylinder body can be achieved by providing a damper at the top of the tower. In addition, since the installation work of the damper can be performed using the steel tower as a scaffold, workability at high places is improved.

According to a fifth aspect of the present invention, there is provided a tower supporting type chimney according to the fourth aspect, wherein the damper operates with respect to a relative displacement in all directions in a horizontal plane between the tower and the tubular body. It is characterized in that a plurality is provided as described above.

In this tower-supported chimney, by providing a plurality of dampers so as to operate for relative displacement in all directions in the horizontal plane, the vibration is effectively attenuated even if the cylinder vibrates in any direction. Is done. Further, by providing a plurality of dampers, even if one of the dampers fails, the other dampers operate to compensate for the failed damper, so that safety is improved. Furthermore, the construction cost can be reduced by using a plurality of relatively small dampers.

According to a sixth aspect of the present invention, there is provided a tower supporting type chimney according to the first, second, third, fourth or fifth aspect, wherein the tower is provided at a plurality of positions having different heights other than a top portion. Are supported in the horizontal direction.

In this tower-supporting chimney, the cylinder below the top of the tower is horizontally supported by the tower, so that the damper provided at the top of the tower attenuates the vibrations that occur in the barrel projecting above the top. At the same time as supporting the wind force by supporting the tubular body below the top with a steel tower, it also has a vibration-resistant structure that resists vibration caused by wind, earthquake, etc. Is enhanced.

According to a seventh aspect of the present invention, there is provided a method for constructing a tower-supporting chimney, wherein the outer shape of the horizontal cross section is substantially equal at any point in the height direction, and the blocks are divided into a plurality of pieces in the height direction. A method for constructing a tower supporting type chimney in which a tubular body is built upright inside a steel tower to be supported and the tubular body is supported from the side by the steel tower, wherein the block body is sequentially assembled to construct the steel tower. It is characterized by comprising one step and a second step of constructing a tubular body inside the steel tower.

In this method of constructing a tower-supporting chimney, the work period on site is shortened by manufacturing the blocks first and assembling the blocks sequentially on the foundation. Also, by constructing the tubular body inside the tower, it is not necessary to separately provide a scaffold, and the construction is simplified.

According to an eighth aspect of the present invention, in the method of constructing a tower-supporting chimney according to the seventh aspect, the second step is performed in parallel with the first step. I do.

In this method of constructing a tower-supporting chimney, the construction period can be shortened by performing the two steps in parallel.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment according to the present invention will be described with reference to FIGS. As shown in FIG. 1, the tower supporting type chimney according to the present embodiment is constructed by erecting a stack 3 of a chimney inside an iron tower 2 constructed by fixing a lower end on a foundation 1. 3 is supported by a steel tower 2.

The turret 2 has a truss structure in which a steel pipe forming a column (leg) 4 arranged in three directions and a steel beam forming a beam 5 between the columns 4 and 4 or a brace 6 between the column 4 and the beam 5 are combined. And a so-called straight tower configuration in which the outer shape of the horizontal cross section is substantially the same at any point in the height direction. The column 4 may be made of a section steel, and the brace 6 may be made of a steel pipe.

As shown in FIG. 2, the steel tower 2 is composed of a plurality of blocks 7 equally divided in the height direction.
The block bodies 7 have the same shape, and have a steel pipe 4a forming a part of the column 4, a beam shaped steel 5a forming a beam 5 by connecting upper ends of the steel pipes 4a to each other, and a lower end of the steel pipe 4a. A bracing section steel 6a constituting a brace 6 is provided between the center of the section steel 5a and the bracing section 6a. A reinforcing member 8 is provided between the steel pipe 4a and the braced section steel 6a.

As shown in FIG. 3, each block 7 has
A connecting member 9 is horizontally installed between the adjacent beams 5 and 5 with the column 4 interposed therebetween. The tubular body 3 is connected to other block bodies 7 except for the block body 7 located at the top of the steel tower 2 via a horizontal support 10 provided on a connecting member 9.

The horizontal support 10 comprises a projection 11 fixed to the side surface of the tubular body 3 and a guide 12 fixed to the connecting member 9 and sandwiching the projection 11 from both sides. The projection 11 is a guide 12
The movement of the cylinder body 3 in the radial direction and the tangential direction is restricted, and only the movement in the vertical direction is free.

A plurality of oil dampers (dampers) 13 are interposed between the connecting member 9 provided on the block body 7 located at the top of the steel tower 2 and the tubular body 3. As shown in FIG. 4, two oil dampers 13 are provided for one connecting member 9, and one of the oil dampers 13 is provided.
a is provided between a vicinity of one end of the connecting member 9 and a damper fixing portion 14 provided at a position closest to the connecting member 9 of the tubular body 3, and another oil damper 13 b is provided at the other end of the connecting member 9. It is installed between the vicinity and the damper fixing part 14. Ball joints are employed at each connecting portion at both ends of the oil damper 13 so as to absorb displacement during operation of the damper and deformation of the cylindrical body 3 due to heat (extension in the length direction occurs). The oil damper 1 for the connecting member 9
The number of 3 is not necessarily two, and the required number is determined by performing vibration analysis or the like.

The cylindrical body 3 is formed by continuously assembling cylindrical steel plates. As an example, a castable lining (not shown) is provided on the inner wall surface to improve heat resistance.
The tubular body 3 is not erected directly on the foundation 1, but has its lower end connected to the tower 2 via a suspending member 15 and is suspended from the tower 2.

The tower 2 is shorter than the barrel 3, and the upper end of the barrel 3 projects from the top of the tower 2 when the entire chimney is viewed from the side. The wall thickness of the side wall of the tubular body 3 is gradually increased from the upper end to the vicinity of the top of the steel tower 2 as it goes downward, and becomes the maximum thickness at the same level as the top of the steel tower 2.
The thickness of the side wall located below the top is gradually reduced toward the bottom. Further, a flue port 16 to which an exhaust duct (not shown) is connected is provided on a lower side surface of the cylindrical body 3.

In the tower supporting type chimney constructed as described above, the steel tower 2 is divided into blocks 7 of the same shape to produce the steel pipe 4a, the beam steel 5a, and the bracing steel 6a.
It becomes possible to standardize each member, and further, a connection portion connecting each member. Thereby, the production cost of the block body 7 is reduced, and the construction cost of the steel tower 2 itself is reduced.

Further, in the tower supporting type chimney configured as described above, since the tubular body 3 is suspended and supported by the steel tower 2, the pull-out force generated when the tubular body 3 receives a force in the lateral direction is reduced. The tower 2 will take over, but the tower 2
Is positioned on the foundation 1 with three pillars 4 located outside the tubular body 3 and has high stability, so that the pull-out force generated when the tubular body 3 receives a lateral force is sufficient. You will be able to compete.

The tubular body 3 protruding above the top of the tower 2 vibrates when subjected to a lateral force, thereby causing a relative displacement between the top of the tower 2 and the tubular body 3. Due to this relative displacement, the oil damper 13 operates to attenuate and suppress the vibration generated in the cylinder body 3.

By providing a plurality of oil dampers 13 as shown in FIG. 4, the vibration is effectively attenuated even if the cylinder 3 vibrates in any direction. Further, by providing a plurality of oil dampers 13, even if one of them fails, the other oil damper 13 fails.
The safety is enhanced because it operates in addition to 3. Furthermore, the construction cost can be reduced by using a plurality of relatively small oil dampers.

In the tower supporting type chimney constructed as described above, the tubular body 3 below the top of the tower 2 is horizontally supported by the tower 2, so that each oil damper installed on the top of the tower 2 A vibration damping structure that attenuates the vibration generated in the cylindrical body 3 protruding above the top at 13 and a cylindrical body 3 below the top supported by the steel tower 2 against the force of the wind, and at the same time caused by wind, earthquake, etc. A vibration-resistant structure against vibration is also provided, and the resistance to wind and earthquake is increased.

In addition, since the tubular body 3 is suspended and supported by the steel tower 2, the bending moment acting on the vicinity of the base of the tubular body 3 is significantly larger than when the tubular body 3 is rigidly fixed to the foundation 2. Become smaller. As a result, the thickness of the side wall of the cylindrical body 3 located below is reduced to a thickness that exerts sufficient strength against bending, and thus the construction cost of the cylindrical body 3 can be reduced.

As described above, according to the tower-supported chimney of the present embodiment, the resistance to wind and earthquake is not impaired.
Construction costs can be further reduced.

In this embodiment, an example is shown in which the steel tower 2 standing on the foundation 1 with three pillars 4 as legs is used. However, the steel tower has four pillars with legs as legs, and more. The number of legs may be adopted.

Next, a second embodiment according to the present invention will be described with reference to FIG.
The description will be given with reference to FIG. Although the oil damper 13 is employed in the first embodiment, other known damper mechanisms, such as a combined use of an oil damper and a spring, may be employed instead. Therefore, in this embodiment, a case where a viscous damper is employed will be described. The components already described in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in FIG. 5, the tubular body 3 located at the top of the steel tower 2 is made of three section steels 17a arranged in parallel with the three beams 5 of the same horizontal position. A triangular frame 17 connects the center of each section steel 17a via the horizontal support portion 10. Shafts 18 extending downward as viscous dampers 20 are provided at the respective vertices of the frame 17.
The discs 19a and 19b are fixed horizontally at an interval vertically. In the present embodiment, three section steels 17a are used for the frame 17, but a steel pipe or the like may be used instead.

On the other hand, as shown in FIG. 6, at the upper end of each column 4 corresponding to each vertex of the frame 17, disks 19a and 19b located at each vertex are arranged inside so that the disk 19
A bottomed cylindrical container 21 having a diameter larger than a and 19b is fixed. Inside the container 21, a partition 22 having the same diameter as the container 21 is disposed between the disks 19a and 19b so as to vertically separate the disks 19a and 19b.
Are fixed by welding or the like to the inner peripheral surface of the. The partition 2
A hole 22a is formed at the center of 2 so as not to interfere with the shaft portion 18.

The container 21 includes a space between the inner bottom of the container 21 and the lower disk 19b, a space between the lower disk 19b and the partition 21 and a space between the partition 22 and the upper disk 19a. Silicone (viscous material) 23 is charged so as to be filled on 19a.

In the tower-supporting chimney configured as described above, the viscous damper 20 can exhibit the same damping property in all horizontal directions, so that the three-way vibration of the cylinder body 3 in any direction is possible. The performance of the viscous damper 20 can be brought out to effectively attenuate the vibration.

In this embodiment, the silicone 23 is used as the viscous body, but other known viscous bodies can also be used.

Next, a third embodiment according to the present invention will be described with reference to FIG.
This will be described with reference to FIGS. In the present embodiment,
A method of constructing the tower supporting chimney described in the first embodiment will be described.

First, the block body 7 is manufactured separately at a factory, and is carried into the site using a transport means such as a truck.
Then, when the foundation work on the site is completed, the construction work is carried out one by one on the foundation 1 using a construction crane (first step).

In parallel with the work of assembling the pylon 2, the tubular body 3 is constructed inside the pylon 2 in the middle of construction. Similarly to the steel tower 2, the cylindrical body 3 is divided into cylindrical blocks 3a and separately manufactured at the factory and transported to the site. In this case, the one located at the tip is lifted one by one using a construction crane. Then, the next block 3a is placed on a trolley and moved, and after being integrated with the upper block 3a, it is lifted again by a construction crane. . (Second
Process)

In the work of assembling the steel tower 2, the components of the horizontal support 10 are attached to each block 7 in advance, and the oil damper 13 is attached to the block 7 to be lifted last. And the tower 2, the barrel 3
After standing up together, connection work with the tubular body 3 is performed.

When the construction of the tower supporting type chimney is carried out as described above, the blocks 7, 3a of the tower 2 and the tubular body 3 are manufactured first, and these blocks 7, 3a are mounted on the foundation 1. By assembling one by one, the work period on site can be shortened. Further, by performing the step of assembling the steel tower 2 and the step of assembling the tubular body 3 in parallel, the construction period can be shortened.

By constructing the tubular body 3 inside the steel tower 2, there is no need to separately provide a scaffold, and the work is simplified. In addition, by attaching the damper mechanism to the block body 7 in advance, work at high places is reduced, and work safety is improved. Therefore, it is possible to further reduce the construction cost, shorten the construction period, and improve the workability.

In this embodiment, the process of assembling the tubular body 3 and the process of constructing the steel tower 2 are performed in parallel. However, the steel tower 2 may be built first, and the tubular body 3 may be assembled later. . In this case, without using a construction crane for assembling the tubular body 3, a wire jack is installed on the steel tower 2, and a erection method for pulling up the tubular body 3 along the steel tower 2 or a jack-up device is used. It is also preferable from the viewpoint of cost reduction that an installation method or the like in which the cylinder body 3 is installed on the base of the cylinder body 3 and the cylinder body 3 is jacked up sequentially from the top block.

Further, in the present embodiment, each block body of the steel tower 2 and the tubular body 3 is manufactured in the factory, but a manufacturing yard may be provided adjacent to the site to assemble the block body 7.

[0051]

As described above, according to the tower supporting chimney according to the first aspect of the present invention, the tower is divided into blocks of the same shape and manufactured, and the tower is assembled by assembling the blocks on the foundation. By constructing, it becomes possible to standardize each member constituting the tower, and it is possible to reduce the manufacturing cost of the block body and reduce the construction cost of the tower itself.

According to the tower supporting type chimney of claim 2,
Since the tubular body is suspended and supported by the steel tower, the steel tower takes on the pulling force generated by the tubular body receiving a lateral force, but the steel tower stands on the foundation outside the tubular body. Since it has higher stability than the cage body, it can exhibit sufficient strength against the pulling force generated in the barrel body. Also, when the cylinder is rigidly fixed on the foundation, a large bending moment acts near the foundation of the cylinder, but by suspending and supporting the cylinder, this bending moment can be significantly reduced. Can be.

According to the third aspect of the present invention, there is provided a tower supported chimney.
Since the tubular body is suspended and supported by the steel tower, the bending moment applied to the vicinity of the base of the tubular body is significantly reduced as compared with the case where the tubular body is rigidly fixed to the foundation. This makes it possible to reduce the thickness of the side wall of the cylindrical body located below to a thickness that exerts sufficient strength against bending, thereby reducing the construction cost of the cylindrical body.

According to the tower supporting type chimney of claim 4,
By providing the damper at the top of the tower, vibration control of the cylinder body can be achieved, and workability in installing the damper can be improved.

According to the tower supporting type chimney of claim 5,
By providing a plurality of dampers so as to operate for relative displacements in all directions in a horizontal plane, even if the cylinder vibrates in any direction, the vibration can be effectively attenuated. Further, even if one of the dampers fails, the other dampers operate to compensate for the failed damper, thereby improving safety. Furthermore, the construction cost can be reduced by using a plurality of relatively small dampers.

According to the tower supporting type chimney of claim 6,
A damper installed at the top of the tower will dampen the vibration that occurs in the cylinder projecting above the top, and the tower below the top will be supported by the tower to counter wind forces, and at the same time as wind, earthquake, etc. A vibration-resistant structure against vibrations caused by the vibration is also provided, and sufficient resistance to wind and earthquake can be exerted.

According to the method of constructing a tower-supporting chimney according to the seventh aspect, the work period on site can be shortened by manufacturing the blocks first and assembling the blocks sequentially on the foundation. Can be. Further, by constructing the tubular body inside the steel tower, it is not necessary to separately provide a scaffold, and the construction can be simplified.

According to the construction method of the steel tower supporting type chimney according to the eighth aspect, the construction period can be shortened by performing the two steps in parallel.

[Brief description of the drawings]

FIG. 1 is a side view of a tower supporting type chimney according to a first embodiment of the present invention.

FIG. 2 is a side view showing the structure of a block constituting a steel tower.

FIG. 3 is a sectional view taken along line III-III in FIG.

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 is a view showing a second embodiment according to the present invention, and is a plan view showing a configuration of a viscous damper installed in a steel tower.

FIG. 6 is a side sectional view showing an internal structure of a viscous damper.

FIG. 7 is a view showing a third embodiment according to the present invention, and is a process diagram showing step by step a method of constructing a tower supported chimney.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Foundation 2 Steel tower 3 Cylindrical body 4 Column 5 Beam 7 Block body 10 Horizontal support part 13 Oil damper (damper) 15 Suspension member 20 Viscous damper

Continued on the front page (72) Inventor Tsutomu Maekawa 4-2-2 Kannon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture Inside Mitsubishi Heavy Industries, Ltd. Hiroshima Works (72) Inventor Hiroshi Kondo 4-2-2 Kanon Shinmachi, Nishi-ku, Hiroshima City, Hiroshima Prefecture No. Mitsubishi Heavy Industries, Ltd. Hiroshima Works

Claims (8)

[Claims] Claims: 1. A tubular body is built upright inside a tower,
A tower supporting chimney supporting the tubular body by the tower, wherein the tower has the same shape in which the outer shape of a horizontal cross section is substantially equal at any point in the height direction and is divided into a plurality in the height direction. A tower supported chimney characterized by being constituted by a block body. 2. The tower-supported chimney according to claim 1, wherein the tubular body is suspended by being connected to the tower at a lower end via a suspension member. 3. The wall thickness of a side wall of the tubular body located below the top of the tower is formed to be thinner than a wall thickness equivalent to the top of the tower. Tower supported chimney. 4. The tower-supported chimney according to claim 1, wherein a damper is interposed between the top of the tower and the tubular body. 5. The tower supporting type according to claim 4, wherein a plurality of the dampers are provided so as to operate with respect to a relative displacement in all directions in a horizontal plane between the tower and the tubular body. chimney. 6. The tower support according to claim 1, wherein the tower supports the tubular body horizontally at a plurality of positions having different heights other than the top. Type chimney. 7. An upright cylindrical body inside a steel tower having a horizontal cross-section having substantially the same outer shape at any point in the height direction and having a plurality of blocks of the same shape divided in the height direction. A method for constructing a tower supporting chimney for constructing and supporting the tubular body by the tower, comprising: a first step of sequentially assembling the block bodies to construct the tower; and constructing a tubular body inside the tower. A method for constructing a tower-supporting chimney, comprising a second step. 8. The method according to claim 7, wherein the second step is performed in parallel with the first step.