JP3891703B2 - Internal chimney hanging support chimney - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an internal chimney suspension type chimney used as an industrial high-rise chimney.
[0002]
[Prior art]
In industrial high-rise chimneys, smoke stacks are installed upright inside an outer support structure such as a steel tower. To reduce the weight of the internal smoke stack, the upper part of the internal smoke stack is suspended and supported by the outer support structure. Supporting methods are being used. FIG. 7 shows an outline of a conventional chimney with a suspended internal chimney.
[0003]
As shown in FIG. 7, a conventional internal chimney suspension support chimney 01 includes an outer support structure 02 having a steel tower structure, an outer cylinder structure, and the like, and an internal smoke cylinder 03 suspended and supported by the outer support structure 02. It is composed of
[0004]
The internal smoke tube 03 is configured such that a plurality of brackets or ring beams 04 attached to the upper outer surface are slidably mounted on an upward horizontal support surface 05 of the outer support structure 02 in a horizontal direction, and sliding in the swivel direction is stopped by a stopper 06. By being restrained, it is supported in a suspension support type. On the other hand, the lower part of the inner smoke tube 03 is movable in the vertical direction by four side surface support members 07 in the X-axis and Y-axis directions orthogonal to each other provided at the respective node heights of the outer support structure 02. It is supported by. A smoke exhaust duct 08 is connected to the lower part of the internal smoke cylinder 03.
[0005]
[Problems to be solved by the invention]
In such a conventional internal chimney suspension chimney 01, the upper part of the internal chimney 03 is suspended and supported by the outer support structure 02 via a bracket or a ring beam 04, and the lower part thereof is at each contact height position. Side support is provided by the side support member 07. Therefore, when an earthquake occurs, the internal smoke tube 03 vibrates in the horizontal direction integrally with the outer support structure 02. Therefore, it is necessary to construct the outer support structure 02 with higher strength and strength, and even if the weight of the inner stack 03 is reduced, the weight of the outer support structure 02 increases, so that the chimney 01 as a whole There is a problem that it is difficult to reduce the weight without changing the weight.
[0006]
The present invention solves such problems, and an object of the present invention is to provide an internal chimney suspension type chimney in which the entire chimney including the outer support structure is reduced in weight.
[0007]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the chimney for supporting and supporting an internal smoke cylinder according to the invention of claim 1 is constructed so that the upper part of the internal smoke cylinder is suspended and supported in a horizontal direction by a load support means having a seismic isolation member interposed in the outer support structure. slidably with support slidably supported along the lower outer peripheral surface of the inner portion Ento in the vertical direction by the lateral support means of the outer support structure, each support by said side support means and said load supporting means A side surface of the inner smoke tube between positions is connected to the outer support structure through an attenuator that absorbs vibration energy in at least a horizontal direction.
[0008]
Further, in the internal chimney suspension chimney according to the invention of claim 2, the outer support structure is provided on the side surface immediately below the support position of the internal smoke cylinder by the load support means via an attenuator that absorbs at least horizontal vibration energy. It is characterized by being connected to the body.
[0009]
In the internal chimney suspension chimney according to the invention of claim 3, at least a plurality of vertical positions on the side surface of the internal chimney between the support positions by the load support means and the side surface support means at least in the horizontal direction. It is characterized by being connected to the outer support structure through an attenuator that absorbs water.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0011]
FIG. 1 is a schematic front view of an internal chimney suspension supporting chimney according to the first embodiment of the present invention, FIG. 2 is an outline modeled by a plurality of vibration modes in the internal chimney suspension supporting chimney of the present embodiment, and FIG. FIG. 4 is a graph showing the relationship of the additional damping constant of the natural vibration mode with the damping coefficient of the attenuator in the internal chimney suspension support chimney of the embodiment. FIG. The graph showing the relationship of the chimney height with respect to the bending moment to generate | occur | produce is shown.
[0012]
As shown in FIG. 1, the internal chimney suspension support chimney 11 of the present embodiment includes an outer support structure 12 and an internal smoke cylinder 13 that is supported by the outer support structure 12. The outer support structure 12 is composed of a steel tower structure, an outer cylinder structure, and the like, and the inner smoke cylinder 13 is supported on the upper part of the outer support structure 12 in a suspended manner by a load support mechanism 14. That is, the lower surfaces of the plurality of brackets or ring beam 15 attached to the upper outer surface of the internal smoke tube 13 are supported by the upward horizontal support surface 16 of the outer support structure 12 via the vibration isolating rubber 17 so as to face the bracket or ring beam 15. ing. That is, the load support mechanism 14 is configured by the bracket or ring beam 15, the upward horizontal support surface 16 of the outer support structure 12, and the vibration isolation rubber 17 interposed therebetween. The load support mechanism 14 may be provided at a lower height than the upper end of the outer support structure 12.
[0013]
A smoke exhaust duct 18 is connected to the lower end of the internal smoke cylinder 13, and the upper position (or lower position) of the connection portion of the smoke exhaust duct 18 intersects each other in the horizontal direction provided in the outer support structure 12. Are supported by four side surface support members 19 in the X-axis and Y-axis directions. Further, an intermediate position between the load support mechanism 14 and the side support member 19 in the inner smoke tube 13 is provided between the outer support structure 12 and at least the X and Y axis directions that intersect each other in the horizontal direction. Supported by an attenuator 20.
[0014]
As described above, the internal smoke cylinder 13 of the internal smoke cylinder suspension support type chimney 11 of this embodiment is supported by the upper load support mechanism 14 on the outer support structure 12, and the lower end portion thereof is vertically supported by the side support member 19. The intermediate portion is supported by being connected to the outer support structure 12 in the horizontal direction by a plurality of attenuators 20.
[0015]
In the internal chimney suspension support chimney 11 of this embodiment, as shown in FIG. 2, FIG. 2 (a) models the outer support structure 12 and the internal chimney 13 as two parallel beams. It is a representation. As an example, the height of the chimney 11 is 150 m, the height from the upper load support mechanism 14 to the lower side support means 19 is about 120 m, and the attenuation coefficient of the attenuator 20 is C = 100 t · s / m.
[0016]
Then, as shown in FIGS. 2B to 2E, when four different vibration modes are modeled, the dotted line indicates the stationary state of the chimney 11, the solid line indicates the state in which the chimney 11 vibrates halfway to one side, It can be seen that the support structure 12 and the internal stack 13 are subjected to different vibrations for each vibration mode.
[0017]
From this, the damping coefficient C = 100 (horizontal axis) of the attenuator 20 in the primary to quaternary vibration modes (FIGS. 2B to 2E) when the attenuator 20 is used, the natural vibration and The additional attenuation constant h (%) · (vertical axis) is as shown in FIG. That is, as shown in FIG. 3, the damping constant (%) of the natural vibration when the attenuator 20 is not used is about 0.5% as a whole. The secondary damping mode h in the secondary vibration mode and the fourth vibration mode having a large vibration difference between the inner smoke cylinder 12 and the internal smoke cylinder 13 are significantly increased as the damping coefficient C of the attenuator 20 increases, and the primary vibration having a small vibration difference. Even in the vibration mode and the third-order vibration mode, the additional damping constant h (%) gradually increases in a range of about 1.7 to 9 times as compared with the case where the attenuator 20 is not used.
[0018]
Therefore, in the internal chimney-suspended chimney 11 of the present embodiment using the attenuator 20 having the attenuation coefficient C = 100 t · s / m, the maximum additional attenuation constant h (%) shown at the right end in the graph of FIG. The vibration damping effect can be obtained.
[0019]
FIG. 4 (a) shows a comparison in structural design against seismic vibration in a conventional internal chimney suspension chimney and FIG. 4 (b) shows an internal chimney suspension chimney 11 of this embodiment. Yes, it shows the result of comparative examination of bending moment (tm) values generated in each chimney by the vibration analysis performed by Kobe Ocean Meteorological Observatory, EL-CENTRO, TAFT, and Hachinohe seismic waves. The graph and the number of inclined points are the response calculation results based on the notification formula of the Ministry of Construction shown as a reference.
[0020]
As can be seen from the graph of FIG. 4, in the conventional chimney with a built-in chimney suspension (FIG. 4 (a)), most of the bending moment generated in the chimney by the seismic wave in each mode is reduced by the Ministry of Construction. In contrast, the internal smoke stack support chimney 11 (FIG. 4 (b)) of this embodiment clearly shows the effect that most of the generated bending moment decreases below the notification formula value. is there.
[0021]
As a result, the conventional chimney suspension support type chimney faces the bending moment, so that the reinforcement of the outer support structure 12 is indispensable. It is clear that the effect of reducing the weight of the body 12 can be obtained.
[0022]
FIG. 5 shows a schematic front view of the internal chimney suspension support chimney according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in embodiment mentioned above, and the overlapping description is abbreviate | omitted.
[0023]
As shown in FIG. 5, the internal chimney suspension support type chimney 31 of the present embodiment has an upper part of the internal smoke cylinder 13 supported by the load support mechanism 14 on the upper part of the outer support structure 12, and a lower part thereof. It is supported by a side support member 19 provided on the outer support structure 12. Further, the intermediate portion of the inner smoke tube 13 is supported by the outer support structure 12 by the attenuator 20, and the side surface immediately below the support position by the load support mechanism 14 is at least horizontally between the outer support structure 12. It is supported by an attenuator 32 that is connected in the X-axis and Y-axis directions that intersect the direction.
[0024]
Therefore, in the internal chimney suspension support type chimney 31 of this embodiment, each vibration mode of FIG. 2 and FIG. 3 representing the operation of the first embodiment described above is at the height position of the load support mechanism 14. The maximum horizontal vibration of the chimney 11 with respect to the stationary state or the maximum horizontal vibration difference between the inner stack 13 and the outer support structure 13 occurs. At this time, the attenuator 32 directly below the load support mechanism 14 absorbs the horizontal vibration energy generated at the height position of the load support mechanism 14, and as a result, the horizontal vibration of the entire internal chimney suspension support chimney 11 is reduced. Effect is obtained. For this reason, it is possible to further reduce the magnitude of the bending moment generated in the outer support structure 12 by the seismic wave.
[0025]
FIG. 6 shows a schematic front view of an internal chimney suspension support chimney according to the third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in embodiment mentioned above, and the overlapping description is abbreviate | omitted.
[0026]
As shown in FIG. 6, the internal smoke cylinder suspension support type chimney 41 of the present embodiment has an upper part of the internal smoke cylinder 13 supported by the load support mechanism 14 on the upper part of the outer support structure 12 and a lower part thereof. It is supported by a side support member 19 provided on the outer support structure 12. In addition, the intermediate portion of the inner smoke tube 13 is located between the support positions of the load support mechanism 14 and the side surface support member 19 and between the outer support structure 12 at least in the X-axis and Y-axis directions. Are supported by a plurality of (three in this embodiment) attenuators 42, 43, and 44 provided in connection with each other. The mounting positions and number of the attenuators 42, 43, 44 are appropriately determined according to the height of the chimney 41.
[0027]
Therefore, in the internal chimney suspension support type chimney 31 of the present embodiment, the horizontal vibration energy generated in the chimney 41 due to the earthquake is loaded with the load support mechanism 14 arranged in multiple stages and the attenuators 42, 43, 44. The effect of reducing the horizontal vibration and bending moment of the entire chimney 41 is obtained.
[0028]
【The invention's effect】
As described above in detail in the embodiment, according to the internal chimney suspension support type chimney of the invention of claim 1, the upper part of the internal smoke cylinder is suspended and supported by the load support means having the seismic isolation member interposed in the outer support structure. And supporting the lower outer peripheral surface of the internal smoke cylinder by the side support means of the outer support structure so as to be slidable in the vertical direction, and the internal smoke cylinder between the support positions of the load support means and the side support means. Since the side surface of the device is connected to the outer support structure through an attenuator that absorbs vibration energy at least in the horizontal direction, the vibration damping effect with the maximum additional damping constant can be obtained, and the generated bending moment can be reduced. The weight of the entire chimney including the outer support structure can be reduced.
[0029]
According to another aspect of the present invention, there is provided an internal support for the internal smoke canister, wherein the side surface immediately below the support position of the internal smoke canopy by the load support means is provided through an attenuator that absorbs at least horizontal vibration energy. Therefore, the magnitude of the bending moment generated in the outer support structure can be further reduced by reducing the horizontal vibration of the entire chimney.
[0030]
Further, according to the internal chimney suspension support chimney of the invention of claim 3, at least horizontal vibration energy is set at a plurality of vertical positions on the side surface of the internal smoke cylinder between the support positions by the load support means and the side support means. Since it is connected to the outer support structure through the absorbing attenuator, the horizontal vibration energy generated can be dispersed and absorbed by the load support mechanism and the multiple attenuators to reduce the horizontal vibration and bending moment of the entire chimney. it can.
[Brief description of the drawings]
FIG. 1 is a schematic front view of an internal chimney suspension chimney according to a first embodiment of the present invention.
FIG. 2 is a schematic diagram modeled by a plurality of vibration modes in the internal chimney suspension chimney of the present embodiment.
FIG. 3 is a graph showing a relationship of an additional damping constant of a natural vibration mode with respect to a damping coefficient of an attenuator in the internal smoke-stack hanging chimney according to the present embodiment.
FIG. 4 is a graph showing the relationship between the chimney height and the bending moment generated when the reference model seismic wave is input in the conventional chimney-suspended chimney of this embodiment.
FIG. 5 is a schematic front view of an internal chimney hanging support chimney according to a second embodiment of the present invention.
FIG. 6 is a schematic front view of an internal chimney hanging support chimney according to a third embodiment of the present invention.
FIG. 7 is a schematic view of a conventional internal chimney hanging support chimney.
[Explanation of symbols]
11, 31, 41 Internal chimney suspension support chimney 12 Outer support structure 13 Internal smoke cylinder 14 Load support mechanism 17 Isolation rubber 19 Side support members 20, 32, 42, 43, 44 Attenuator

Claims (3)

The upper support of the inner smoke tube is supported in a slidable and horizontally slidable manner by a load support means having a seismic isolation member interposed in the outer support structure, and the lower outer peripheral surface of the inner smoke tube is supported by the outer support structure. An attenuator that is slidably supported in the vertical direction by side support means, and that absorbs vibration energy at least in the horizontal direction at the side surface of the internal smoke tube between the support positions of the load support means and the side support means. An internal chimney suspension supporting chimney connected to the outer support structure via   2. The internal chimney suspension support chimney according to claim 1, wherein a side surface immediately below a support position of the internal chimney by the load support means is attached to the outer support structure through an attenuator that absorbs at least horizontal vibration energy. Internal chimney hanging support chimney characterized by being connected.   2. The internal chimney suspension support chimney according to claim 1, wherein at least a plurality of vertical positions on the side surface of the internal smoke cylinder between the support positions of the load support means and the side surface support means absorb at least horizontal vibration energy. An internal chimney suspension support chimney connected to the outer support structure through an attenuator.

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