JP7727438B2 - Dome structure - Google Patents

Description

The present invention relates to a dome structure.

Conventionally, a dome structure has been proposed in which a tension ring body and a compression ring body are connected by a beam (see, for example, Patent Document 1).

Special Publication No. 2002-542410

A conventional dome structure is a stable structure in which the force system is closed against the constant load on the dome, in other words, the static load.
However, during an earthquake, if the axial force acting on the beams fluctuates and the deformation increases beyond the allowable strength of the beams, this balance may be lost and global buckling may occur. In particular, if the fluctuating axial force and bending moment of the beams due to vertical earthquakes (pitch-sway earthquakes) cause the beams to yield and become plastic, or if a sudden increase in deformation occurs due to member buckling, the balance of stress and deformation of the entire dome will be lost and the stability of the dome roof will be suddenly reduced.

The present invention takes the above into consideration and aims to provide a dome structure that can ensure stability in the event of an unexpected vertical earthquake.

The dome structure of the first aspect includes a tension ring body supported by a structural body, a compression ring body provided above and inside the tension ring body, a plurality of beam members extending diagonally upward and inward from the tension ring body and connected to the compression ring body, and a tension control unit that controls the tensile force acting on the tension ring body.

In the dome structure according to the first aspect , during an up-and-down earthquake, an additional tensile force acts on the tension ring body in the circumferential direction due to the compressive axial force and bending moment acting on the beams.
The tensile force acting on the tension ring body can be controlled by the tension control unit, and the axial force and bending moment acting on the beam material are suppressed.
This prevents the beams from yielding and becoming plastic due to vertical earthquakes, and prevents the beams from buckling, ensuring the stability of the dome structure.

The dome structure of the second aspect includes a tension ring body supported by a structural body, a plurality of beam members extending diagonally upward and inward from the tension ring body, a fixing portion provided on the upper inside of the tension ring body and connecting the tip ends of the plurality of beam members, and a tension control portion that controls the tensile force acting on the tension ring body.

In the dome structure according to the second aspect , during an up-and-down earthquake, an additional tensile force acts on the tension ring body in the circumferential direction due to the compressive axial force and bending moment acting on the beams.
The tensile force acting on the tension ring body can be controlled by the tension control unit, and the axial force and bending moment acting on the beam material are suppressed.
This prevents the beams from yielding and becoming plastic due to vertical earthquakes, and prevents the beams from buckling, ensuring the stability of the dome structure.
The fixed portion includes both a portion that directly connects the tip ends of the beams together, and a portion that connects the tip ends of the beams with a member other than a ring, such as a disk.

The invention of the third aspect is a dome structure of the first or second aspect , in which the tension ring body has a connecting portion at at least one location in the circumferential direction, and the tension control portion has a tensioning member that connects one end of the tension ring body to the other end at the connecting portion while applying a tensile force, and stretches when a tension greater than a preset tension is applied to the tension ring body.

In the dome structure of the third aspect , when a pulling force greater than a preset tension acts on the tension ring body, the tension member to which the tension force is applied extends, thereby preventing an excessive increase in the tension force acting on the tension ring body.
This suppresses excessive axial force and bending moment generated in the beam material, and makes it possible to suppress plastic deformation and buckling of the beam material.

As explained above, the dome structure of the present invention has the excellent effect of ensuring stability in the event of an unexpected vertical earthquake.

1 is a perspective view showing a dome to which the dome structure according to the first embodiment is applied. 1A is a cross-sectional view showing an example of a tension control unit, and FIG. 1B is a cross-sectional view showing the tension control unit when tension is applied. 10A is a cross-sectional view showing another example of a tension control section, and FIG. 10B is a cross-sectional view showing the tension control section when tension is applied. 10A is a cross-sectional view showing another example of a tension control section, and FIG. 10B is a cross-sectional view showing the tension control section when tension is applied. 10A is a cross-sectional view showing an example of a tension control section of a compression ring body used in a dome structure according to a second embodiment, and FIG. 10B is a cross-sectional view showing the tension control section when a compressive force is applied. FIG. 11 is a perspective view showing an example of a tension control unit of a compression ring body used in a dome to which the dome structure according to the third embodiment is applied. FIG. 10 is a perspective view showing a dome to which a dome structure according to a fourth embodiment is applied. FIG. 10 is a perspective view showing a dome to which a dome structure according to another embodiment is applied.

[First embodiment]
A dome structure according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.
1 is a perspective view of a building 12 equipped with a dome 10 to which a dome structure according to an embodiment of the present invention is applied. The building 12 of this embodiment may be a stadium, for example, but may be something other than a stadium.

The building 12 comprises a circular structure 14. Spectator seats (not shown) are provided on the inner periphery of the structure 14, for example.

The dome 10 is provided on top of the structure 14. The dome 10 is composed of an annular tension ring body 16, an annular compression ring body 18 located inside and above the tension ring body 16, multiple beam members 20 that connect the tension ring body 16 and the compression ring body 18 and extend in the radial direction (radial direction) of the tension ring body 16 and the compression ring body 18, and a roof member 22. The roof member 22 is provided over the entire space between the tension ring body 16 and the compression ring body 18, but only a portion of it is shown in Figure 1.

The tension ring body 16 comprises multiple (four in this embodiment) arc-shaped ring pieces 16A, and adjacent ring pieces 16A are connected via a tension control unit 24. The ring pieces 16A are, for example, made of steel or the like. The compression ring body 18 and beam material 20 are also made of steel or the like.

The tension ring body 16 is supported by multiple bearing materials 26 installed on top of the structure 14, allowing the tension ring body 16 to expand and contract in the circumferential direction. Examples of the bearing materials 26 that can be used include laminated rubber made by alternating layers of steel plates and rubber layers, sliding bearings, and rolling bearings.

The tension control unit 24 controls the circumferential tension of the tension ring body 16, and as an example, the structure shown in Figures 2 to 4 is applied.

First, the tension control unit 24 shown in FIG. 2 will be described.
As shown in Figure 2, the ring piece 16A has a hollow structure, for example, a square pipe shape, and its circumferential ends are closed with a cover member 28. A partition wall 30 is fixed inside the ring piece 16A at a position away from the cover member 28.

A tension member 32 is provided so as to penetrate the cover member 28 of each of the ring pieces 16A and the partition wall 30. The tension member 32 is preferably made of a material that is more stretchable than the ring pieces 16A. For example, the tension member 32 can be made of PC steel rods, strands, etc.

In this embodiment, the tension member 32 is made of PC steel rod and has male threads 34 formed at both ends, onto which nuts 36 are threaded. The nuts 36 are tightened while in contact with the bulkhead 30, applying a tensile force (prestress) to the tension member 32 in advance.

(Action, effect)
Next, the effects of the dome 10 having the tension control unit 24 shown in FIG. 2A provided on the tension ring body 16 will be described.
During normal times (when stationary) when no earthquake is occurring, the tension ring body 16 is constantly subjected to circumferential tension (arrow A) due to the loads of the compression ring body 18, beam material 20, and roof material 22 acting from the radial inside to the outside.

When a vertical earthquake occurs, the entire dome 10 moves up and down, causing the axial force of the beams 20 to fluctuate. The compressive axial force and bending moment acting on the beams 20 then exert a greater tension on the tension ring 16 than usual.

When a large tension acts on the tension control section 24 and exceeds the pre-tensioning force (prestress), as shown in Figure 2 (B), the tension control section 24 separates, the tension member 32 extends, and the tension ring body 16 extends circumferentially, suppressing the axial force and bending moment acting on the beam 20. This prevents the beam 20 from yielding and becoming plastic or buckling due to a vertical earthquake, ensuring the stability of the dome 10.

Next, the tension control unit 24 shown in FIG. 3A will be described.
In the tension control unit 24 shown in Figure 3(A), the end of one ring piece 16A and the end of the other ring piece 16A (on the right side of the drawing) are connected by a rod-shaped or plate-shaped tension member 38 made of low-yield-point steel. Low-yield-point steel is a steel material that stretches more easily than the steel material that makes up the ring pieces 16A. In the tension ring body 16 shown in Figure 3(A), the portion connected by the tension member 38 is defined as a connecting portion 39.

In this embodiment, the tension member 38 is formed so that the central portion in the longitudinal direction has a smaller diameter than the end portions in the longitudinal direction, making the central portion more easily stretchable. The tension member 38 may have the same cross-sectional area along its entire length (constant diameter along its entire length), in which case it can be designed to have a low yield strength to allow for early elongation and deformation.

Next, the effects of the dome 10 equipped with the tension control unit 24 shown in FIG. 3A will be described.
In this embodiment, when a large tensile force acts on the tension control unit 24, as shown in Figure 2 (B), the tension members 38 elongate, suppressing the axial force and bending moment generated in the beam 20. This prevents the beam 20 from yielding and becoming plastic or buckling due to a vertical earthquake, ensuring the stability of the dome 10.

Next, the dome 10 equipped with the tension control unit 24 shown in FIG. 4(A) will be described.
In this tension control unit 24, a box-shaped protrusion 40 made of steel is integrally formed on the lower half of the end of one ring piece 16A (left side of the drawing), and a box-shaped protrusion 42 made of steel is integrally formed on the upper half of the end of the other ring piece 16A (right side of the drawing).

The lower wall 42A of the upper protrusion 42 and the upper wall 40A of the lower protrusion 40 face each other.
A sheet-like friction member 44 is attached to the lower surface of the lower wall 42A of the upper protrusion 42. The friction member 44 may also be attached to the upper wall 40A of the lower protrusion 40.
The friction member 44 can be formed, for example, from a material similar to the brake material used in automobile brakes, and is formed from a material having a higher coefficient of friction than steel.

Multiple bolts 46 pass through the lower wall 42A of the upper protrusion 42 and the upper wall 40A of the lower protrusion 40. The lower wall 42A of the upper protrusion 42, the upper wall 40A of the lower protrusion 40, and the friction member 44 are sandwiched between the nut 48 threaded onto the bolt 46 and the head 46A of the bolt 46, and the friction member 44 is pressed against the lower wall 42A of the upper protrusion 42.

The bolt 46 passes through a round hole 49 formed in the lower wall 42A of the upper protrusion 42 and passes through an elongated hole 51 formed in the upper wall 40A of the lower protrusion 40. This elongated hole 51 is formed long in the circumferential direction of the tension ring body 16.
The tension of the bolt 46 generates a large surface pressure on the friction member 44, thereby generating a frictional force. Furthermore, by adjusting the tension of the bolt 46, the frictional force can be adjusted.

Normally, as shown in Figure 4(A), the bolt 46 is positioned inside the elongated hole 51, shifted to one side (the left side of the figure), with a gap provided on the right side of the figure. This gap allows one ring piece 16A and the other ring piece 16A to be spaced apart from each other, as shown in Figure 4(B).

Next, the effects of the dome 10 equipped with the tension control unit 24 shown in FIG. 4A will be described.
When an up-and-down earthquake occurs and the entire dome 10 moves up and down, the axial force of the beam 20 fluctuates, and a large tensile force acts on the tension control unit 24, as shown in Figure 4 (B), the friction member 44 slides while being pressed against the upper wall 40B of the lower protrusion 40, causing one ring piece 16A and the other ring piece 16A to move apart circumferentially, and the tension ring body 16 stretches circumferentially.

This suppresses the axial force and bending moment acting on the beams 20, preventing the beams 20 from yielding and becoming plastic or buckling due to an up-and-down earthquake, thereby ensuring the stability of the dome 10.

Second Embodiment
Next, a dome 10 to which a dome structure according to a second embodiment of the present invention is applied will be described. Note that the same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted.
5A, in the dome 10 of this embodiment, a tension control unit 24 is provided on the compression ring body 18. The compression ring body 18 includes a plurality of ring pieces 18A formed in an arc shape, and adjacent ring pieces 18A are connected to each other via the tension control unit 24.

As shown in Figure 5(A), in the normal state of the tension control unit 24 of this embodiment, gaps are provided between the end of the upper protrusion 42 formed on the ring piece 18A on the right side of the drawing and the end of the ring piece 18A on the left side of the drawing, and between the end of the lower protrusion 40 formed on the ring piece 18A on the left side of the drawing and the end of the ring piece 18A on the right side of the drawing. When a compressive force (arrow B) acts on the compression ring body 18, one ring piece 18A and the other ring piece 18A move toward each other, and the compression ring body 18 contracts circumferentially.

This suppresses the axial force and bending moment acting on the beams 20, preventing the beams 20 from yielding and becoming plastic or buckling due to an up-and-down earthquake, thereby ensuring the stability of the dome 10.

[Third embodiment]
Next, a dome 10 to which a dome structure according to a third embodiment of the present invention is applied will be described. Note that the same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted.
In the dome 10 of this embodiment, a tension control unit 24 shown in FIG. 6 is provided on the compression ring body 18 .

A first tension rod connection part 50 that is L-shaped in side view is formed on one ring piece 18A, and a second tension rod connection part 52 that is L-shaped in side view and faces in the opposite direction to the first tension rod connection part 50 is formed on the other end of the other ring piece 18A.

The end 50A of the first tension rod connection portion 50 and the end 52A of the second tension rod connection portion 52 are connected by a tension member 38 similar to that in the first embodiment.

(Action, effect)
Next, the effects of the dome 10 having the tension control section 24 shown in FIG. 6 on the compression ring body 18 will be described.

When a vertical earthquake occurs, the entire dome 10 moves up and down, and a compressive force greater than normal acts on the compression ring body 18, causing the tension member 38 to stretch and the compression ring body 18 to be compressed in the circumferential direction (arrow B).
This suppresses the axial force and bending moment generated in the beam material 20, and prevents the beam material 20 from yielding and becoming plastic due to an up-and-down earthquake, or from buckling, thereby ensuring the stability of the dome 10.

[Fourth embodiment]
Next, a dome 10 to which a dome structure according to a fourth embodiment of the present invention is applied will be described. Note that the same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted.
As shown in FIG. 7, in the dome 10 of this embodiment, both the tension ring body 16 and the compression ring body 18 are formed uniformly in the circumferential direction from a steel material or the like.

In the dome 10 of this embodiment, the tension ring body 16 is supported by a plurality of pillars 54. The pillars 54 are made of steel or the like and support the load of the dome 10, but are also capable of bending and deforming. In this embodiment, the pillars 54 serve as the tension control unit 24.
The pillars 54 may be erected on top of the structure 14 or may be erected on the foundation or ground.

(Action, effect)
Next, the effects of the dome 10 of this embodiment will be described.
When a vertical earthquake occurs, the entire dome 10 moves up and down, the axial force of the beam 20 fluctuates, and a tensile force (arrow A) acts on the tension ring body 16 in the circumferential direction. This causes the tension ring body 16 to stretch circumferentially and expand in diameter, and the columns 54 supporting the tension ring body 16 bend and deform radially outward from the tension ring body 16.

This suppresses the axial force and bending moment acting on the beams 20, preventing the beams 20 from yielding and becoming plastic or buckling due to an up-and-down earthquake, thereby ensuring the stability of the dome 10.

[Other embodiments]
The above describes one embodiment of the present invention, but the present invention is not limited to the above, and it goes without saying that the present invention can be implemented in various modified forms within the scope of the gist of the present invention.

In the above embodiment, the shape of the dome 10 was circular, but the shape of the dome 10 is not limited to circular, and may be polygonal or elliptical.

In the above embodiment, the compression ring body 18 is disposed inside the tension ring body 16, and the end of the beam material 20 extending radially inward from the tension ring body 16 is connected to the compression ring body 18. However, the connection target of the end of the beam material 20 is not limited to the compression ring body 18. For example, as shown in Figure 8, a disk-shaped fixing portion 56 may be provided instead of the compression ring body 18, and the end of the beam material 20 may be connected to this fixing portion 56.

Also, although not shown in the figures, the ends of multiple beams 20 may be directly connected to each other at the center of the dome 10.

REFERENCE SIGNS LIST 10 Dome 14 Structure 16 Tension ring body 18 Compression ring body 20 Beam 24 Tension control unit 38 Tension member 39 Connection portion 56 Fixation portion

Claims (3)

a tension ring body supported by the structure;
a compression ring body provided on the upper inner side of the tension ring body;
a plurality of beam members extending obliquely upward and inward from the tension ring body and connected to the compression ring body;
a tension control unit that stretches the tension ring body in a circumferential direction when a tension greater than a preset tension acts on the tension ring body ;
A dome structure having a tension ring body supported by the structure;
a plurality of beam members extending obliquely upward and inward from the tension ring body;
a fixing portion provided on the upper inner side of the tension ring body and connecting the tip ends of the plurality of beam members;
a tension control unit that controls the tensile force acting on the tension ring body;
A dome structure having The tension ring body has a connecting portion at at least one location in the circumferential direction,
The tension control section has a tension member that connects one end and the other end of the tension ring body at the connecting section in a state where a tension force is applied, and that extends when a tension greater than a preset tension acts on the tension ring body.
The dome structure according to claim 1 or 2.