JP5164012B2 - Seismic reinforcement structure for spherical tank legs - Google Patents

Description

  The present invention relates to a seismic reinforcement structure for a leg portion of a spherical tank, which is improved in safety against an earthquake with respect to a spherical tank that stores compressed gas, liquefied gas, and the like.

Based on FIG. 5, the leg part structure which supports the spherical shell (it consists of a spherical shell board) of a spherical tank is demonstrated.
The spherical tank 1 supports a spherical shell 3 with a leg structure 2.
The leg structure 2 includes a foundation 5, a support section 6 that stands on the foundation 5 and supports the spherical shell 3, and a connection that connects the support 6 to the spherical shell 3. It is formed by a portion 4 and a brace 7 provided so as to be inclined and crossed between the support portions 6 and 6.
(A) shows the spherical tank which has the pipe brace 71 formed with a steel pipe, (b) shows the spherical tank 1 which has the tie rod brace 72 which provided the turn buckle in the steel bar material.

FIGS. 6A and 6B show a conventional example of reinforcing a support portion 6 of a spherical tank 1 having a tie rod brace using a shape steel material. FIG. 6A shows a lower portion of the support portion 6, and FIG. Show.
When the support portion 6 of the leg structure 2 that supports the spherical shell 3 of the spherical tank 1 is subjected to earthquake-proof reinforcement, it is reinforced using a shape steel material 61 or the like. The shaped steel members 61 are, for example, arranged in a plurality of vertical rows along the outer peripheral surface of the support portion 6 using channel steel materials having a U-shaped cross section, and are fixed by welding. Furthermore, although not shown, each member of the pipe brace or tie rod brace is reinforced with earthquake resistance by reinforcing it with a shape steel material or replacing it with a new member having improved strength.

  The invention of the prior art in which the existing spherical tank leg portion, which is improved in durability and earthquake resistance by suppressing displacement due to vibration or shaking due to an earthquake or strong wind, is disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-2006. There is an invention of No. 273398 “Reinforcing structure of spherical tank legs”. According to the present invention, an annular support frame provided in the vicinity of a foundation with respect to an existing spherical tank support, an inclined material provided from the support frame to the support, and the inclined material and the support are provided. It is a reinforcing structure that is formed into an integral rigid structure with the connecting horizontal beam material, and the column, the inclined material, and the horizontal beam material are joined to each other by bolt connection etc. at the column mounting portion via the bending material. It is a rigid structure that is assembled and constructed on site without using fire.

  The invention of the prior art relating to the reinforcement modification of an existing spherical tank with improved durability and seismic resistance of the column and foundation against vibrations and shaking caused by earthquakes or strong winds is disclosed in Patent Document 2 by the present applicant. There is an invention of Japanese Patent Application Laid-Open No. 2008-162657 “Structure and Construction Method of Legs of Spherical Tank”. The present invention includes an upper support column that protrudes outward in the horizontal direction from a spherical shell of an existing spherical tank, a support column that is installed vertically from the upper support column and supports the existing spherical tank vertically, and a footing that supports the support column. This is a reinforcing structure for the legs of an existing spherical tank in which a foundation made of a pedestal is provided at an outer peripheral position from directly below the spherical shell body of the existing spherical tank.

JP 2006-273398 A JP 2008-162657 A

  When the spherical tank 1 shown in FIG. 5 is reinforced to improve earthquake resistance, the load applied by the earthquake and strong wind applied to the spherical tank is applied in all directions with respect to the legs, so that FIGS. 6 (a) and 6 (b) of the conventional example. The reinforcement structure of the leg portion where the steel members 61 are welded in a plurality of vertical rows on the outer peripheral surface of the columnar support portion 6 shown in FIG. Occurred. Also, the aesthetic appearance was not good due to the reinforcing member.

  In the invention of Japanese Patent Application Laid-Open No. 2006-273398, “Reinforcing Structure of Spherical Tank Leg” of Patent Document 1, an annular frame member, an inclined member, and a horizontal beam member are combined on the outer periphery of a support column that supports an existing spherical tank. Although the structure is designed to improve the work efficiency through safe work, a large space is required around the spherical tank.

  Further, the invention of Japanese Patent Application Laid-Open No. 2008-162657 “Structure and Construction Method of Legs of Spherical Tank” in Japanese Patent Application Laid-Open No. 2008-162657 is a reinforcement modification of an existing spherical tank with improved durability and seismic resistance of columns and foundations. However, it was necessary to install new struts on the spherical shell surface and to modify the foundation.

The present invention has been made in view of the problems of the prior art as described above, and its object is to make it stronger than the conventional structure against pitching and rolling due to earthquakes and strong winds. To improve safety, and to provide a seismic reinforcement structure for the leg of a spherical tank with a simple structure and easy construction for repairing a corroded or damaged part.

Legs seismic reinforcement structure of spherical tank according to the invention of claim 1, the support portion 6 of the existing leg structure 2 extending from the base 5 for supporting a Tamakaratai 3 spherical tank 1 to Tamakaratai 3 and be a clearance from the respective outer surface of the support portion 6 and the connecting portion 4 over the entire connection unit 4 outer periphery, between the new half cylindrical tube divided into a plurality in the longitudinal direction a longitudinal joint strip shaped to A new cylindrical support member 8 which is provided by welding by providing a backing plate 11 and is integrally formed by welding by providing a semi-short tubular backing ring 10 at a circumferential joint portion along the circumferential direction of the new half cylinder. And a gap is provided from the outer surface over the entire outer periphery of the existing pipe braces 71 and 71 provided between the existing support portions 6 and 6 that support the spherical shell 3 of the spherical tank 1. Te, new half divided into a plurality in the longitudinal direction Welding and a backing ring 10 of the semi-minor tubular disposed in a circumferential joint portion along the circumferential direction of the new semi-cylindrical in the longitudinal joint between the cylinder tube provided with strip-shaped backing plate 11 welding to, characterized in that the coating formed by the novel cylindrical brace 9, 9 formed integrally.

The spherical tank leg seismic strengthening structure according to the invention of claim 2 is the leg seismic strengthening structure of the spherical tank according to claim 1 , wherein the gap between the existing support part 6 and the new cylindrical support member 8 ; Each of the gaps between the existing pipe brace 71 and the new cylindrical brace 9 is provided with a semicircular guide ring 12 that maintains the gap and improves the assembly accuracy.

Legs seismic reinforcement structure of spherical tank according to the invention of claim 1, the support portion 6 of the existing leg structure 2 extending from the base 5 for supporting a Tamakaratai 3 spherical tank 1 to Tamakaratai 3 and be a clearance from the respective outer surface of the support portion 6 and the connecting portion 4 over the entire connection unit 4 outer periphery, between the new half cylindrical tube divided into a plurality in the longitudinal direction a longitudinal joint strip shaped to A new cylindrical support member 8 which is provided by welding by providing a backing plate 11 and is integrally formed by welding by providing a semi-short tubular backing ring 10 at a circumferential joint portion along the circumferential direction of the new half cylinder. And a gap is provided from the outer surface over the entire outer periphery of the existing pipe braces 71 and 71 provided between the existing support portions 6 and 6 that support the spherical shell 3 of the spherical tank 1. Te, new half divided into a plurality in the longitudinal direction Welding and a backing ring 10 of the semi-minor tubular disposed in a circumferential joint portion along the circumferential direction of the new semi-cylindrical in the longitudinal joint between the cylinder tube provided with strip-shaped backing plate 11 since coating formed by new cylindrical brace 9, 9 which is integrally formed by welding, the strip-shaped backing plate 11 in the longitudinal joint of the half cylinder provided Hantan the circumferential joint portion of the half cylindrical By providing the tubular backing ring 10, the new cylindrical support member 8 or the joint portion of the new cylindrical brace 9 can be properly positioned and reliably welded.
Further, these backing ring 10 and backing plate 11 are attached in advance to a joint portion of a new cylindrical support member 8 or a new cylindrical brace 9 at the factory, so that temporary assembly becomes easy at the time of assembly at the site. The parts can be reliably aligned.
Thus, by providing the backing ring 10 and the backing plate 11, the dimension setting and accuracy of the joint portion are improved and complete welding can be performed, so that an appropriate connection structure can be obtained.
In addition, since a cylindrical support member with a uniform cross-sectional shape in any direction is used without the need for a reinforcing member such as a shape steel material, the load applied to all the surroundings of the support part of the reinforced leg part and the connection part In contrast, since the durability strength is uniform and a cylindrical reinforcing member is used, the reinforcing structure is smart, stable, and excellent in appearance.
Using a half-cylinder tube and dividing the half-cylinder tube into a plurality of parts in the longitudinal direction reduces the weight and dimensions, facilitates on-site adjustment, facilitates assembly, and allows installation at multiple locations at the same time. It is possible, and the efficiency of on-site construction can be improved efficiently and safely.
Moreover, the corrosion location of a support part or a connection part, a damage location, etc. can be repaired partially, and can be reinforced.
Further, such cross-section of the connecting portion and a pipe braces between the pipe brace and the support portion, because it reinforces the likely locations such as damage or buckling of the pipe braces, to pitch and roll such as earthquakes and strong winds Strong spherical tank legs can be seismic strengthened.
Furthermore, we leave using Ttei because the supporting portion of the existing members, is more strength integral is achieved by the novel cylindrical support member increases.

The spherical tank leg seismic strengthening structure according to the invention of claim 2 is the leg seismic strengthening structure of the spherical tank according to claim 1 , wherein the gap between the existing support part 6 and the new cylindrical support member 8 ; along each of the gap between the existing pipe brace 71 and the new cylindrical brace 9, since providing the semicircular plate-like guide ring 12 to improve the assembly precision retaining the spacing of the gap, the existing cylindrical in situ Therefore, when installing the new half-cylinder cylindrical member, it is possible to prevent twisting of the semicircular member, easily align with the existing member, ensure a cylindrical shape without shifting the center, and set and assemble accurately and accurately since it is possible to easily, the work can be performed efficiently repair work.
Further, the guide ring 12 is attached to each of the half cylindrical members of the new cylindrical support member 8 and the new cylindrical brace 9 in advance at the factory, thereby preventing torsion and ensuring an accurate half cylindrical shape. The shape can be maintained during transportation and assembly.

It is explanatory drawing which shows the case of the spherical tank which has a pipe brace in 1st Embodiment of the earthquake-resistant reinforcement structure of the spherical tank leg part concerning this invention. FIG. 2 is an explanatory diagram of the main part of FIG. 1, (a) is an upper part of the support part, (b) is an intermediate part of the support part, (b ′) is an intermediate intersection part of the pipe brace, and (c) is a lower part of the support part. is there. It is explanatory drawing of the principal part of the tie rod brace which shows 2nd Embodiment, (a) is the upper part of a support part, (b) is the intermediate part of a support part, (c) is the lower part of a support part. In the example of the reinforcing member provided in the pipe material, (a) is an explanatory view of a side surface and a longitudinal section, and (b) is an exploded perspective explanatory view. In a general case of a spherical tank, (a) is an overall side view of a spherical tank having a pipe brace, and (b) is an overall side view of a spherical tank having a tie rod brace. About the spherical tank which has a tie rod brace of a prior art example, it is a principal part of the example which reinforces a support part using a shape steel material, (a) is a lower side view of a support part, (b) is AA horizontal cross-section explanation FIG.

An embodiment of a seismic reinforcement structure for a spherical tank leg according to the present invention will be described with reference to FIGS.
The same reference numerals are used for the same terms throughout FIGS. 1 to 4, and a part of the description of each reference is omitted. This embodiment is applied to seismic reinforcement of a leg of a spherical tank having an existing pipe brace and a spherical tank having a tie rod brace.
The number of support parts 6 that support the spherical shell 3 with the connection part 4 increases to 6, 8, 10, 12, etc. according to the scale of the spherical tank 1.
The present invention is not limited only to the following embodiments, and modifications (for example, omission or addition of components, changes in shape of components, etc.) are made to the following embodiments without departing from the gist of the present invention. Of course you can.

1 and 2 show an example of a spherical tank having a pipe brace as a first embodiment of the seismic reinforcement structure for a spherical tank leg according to the present invention.
The spherical tank 1 supports a spherical shell 3 with a leg structure 2.
The leg structure 2 includes a foundation 5, a support section 6 that stands on the foundation 5 and supports the spherical shell 3, and a connection that connects the support 6 to the spherical shell 3. It is formed by a portion 4 and a brace 7 provided so as to be inclined and crossed between the support portions 6 and 6.
FIG. 1 shows a coating of a new cylindrical support member 8 erected vertically from the foundation 5 on the outer periphery of an existing support portion 6 extending from the foundation 5 supporting the spherical shell 3 of the spherical tank 1 to the spherical shell 3. The case of integral forming by welding is shown.
Further, when the existing brace 7 is a pipe-structured brace 71 as shown in the figure, a new cylindrical brace 9 is coated on the outer periphery of the brace 71 in an inclined direction and integrally formed by welding.

2A and 2B are explanatory views of the main part of FIG. 1, wherein FIG. 2A is an upper part of the support part, FIG. 2B is an intermediate part of the support part, FIG. It is the lower part of the part.
New cylindrical support members 8a, 8b and 8c are coated on the outer periphery of the existing support portion 6 connected to the lower end edge of the connection portion 4 with the spherical shell, and are integrally formed by welding.
The new cylindrical support members 8a, 8b, and 8c are integrally formed by covering and covering the entire outer periphery of the support portion of the existing leg as shown in the figure. Alternatively, the part that has been corroded or damaged is partially covered and repaired or reinforced by welding.
As described above, the reinforcing structure in which the new cylindrical support members 8a, 8b, and 8c are covered and integrally formed by welding does not require a reinforcing member such as a shape steel material, and the cylindrical support has a uniform cross-sectional shape in any direction. By using the member 8, endurance strength can be obtained with respect to loads in all directions around the support portion 6.
In addition, since a cylindrical reinforcing member is used, the reinforcing structure is smart, stable and aesthetically pleasing.
Using a split cylindrical tube and dividing it into multiple parts reduces weight and dimensions, facilitates on-site adjustment, is easy to assemble, and can be installed at multiple locations at the same time. Reinforcement work is performed well, and the efficiency of site construction can be improved.
Since the supporting member 6 of the existing member can be used as it is, integration with the new cylindrical supporting members 8a, 8b, and 8c is achieved, and the strength is further increased.
As described above, since the construction on the support portion 6 and the brace 71 does not affect the spherical tank body, the construction work can be performed while the body is being used.

Further, new cylindrical braces 9a, 9b, 9c are coated on the outer periphery of the pipe brace 71 of the existing pipe structure in the inclined direction and integrally formed by welding.
The new cylindrical braces 9a, 9b, and 9c are integrally formed by covering the entire outer periphery of the existing pipe brace 71 and welding.
Thus, the outer circumference to the new cylindrical brace 9a of the existing pipe brace 71, 9b, by integrally forming at 9c were coated welded, reinforced new cylindrical brace 9 a, 9b, in the circumferential direction of the load 9c On the other hand, the durability is uniform, and the reinforcing structure is excellent in aesthetics using a simple structural member.
In particular, the pipe brace 71 and the support portion 6 are connected to each other, and the pipe brace 71 such as a crossing portion is reinforced so that the pipe brace 71 is easily damaged or buckled. A strong seismic reinforcement structure for spherical tank legs is obtained.
This new cylindrical brace 9a, 9b, 9c is divided into a plurality of parts, so that the weight and dimensions are reduced, the adjustment on the site is easy, the assembly is easy, and the construction can be performed at a plurality of locations at the same time. Streamline on-site construction.
Like the support member, the pipe brace 71 can be used while leaving the existing member as it is, so that the old and new members can be integrated and the strength can be further improved.

3A and 3B are explanatory views showing the seismic reinforcement structure of the spherical tank leg portion having the tie rod brace of the second embodiment, wherein FIG. 3A is an upper portion of the support portion, FIG. 3B is an intermediate portion of the support portion, and FIG. It is the lower part of a support part.
New cylindrical support members 8a, 8b, and 8c are coated on the outer periphery of the existing support portion 6 connected to the lower portion of the connection portion 4 with the spherical shell and integrally formed by welding.
The brace 72 having the existing tie rod structure is replaced with a new tie rod brace, or a new cylindrical brace is newly attached in an inclined direction (not shown).

The spherical tank leg reinforcing structure having a tie rod brace according to the second embodiment is thus formed by covering the outer periphery of the existing support portion 6 with the new cylindrical support members 8a, 8b, 8c and integrally forming them by welding. Using simple structural members, it is possible to efficiently perform reinforcement work in a safe operation and improve earthquake resistance.
The brace 72 having an existing tie rod structure can be replaced with a new brace 7c having the same tie rod structure to provide a reinforcing structure, or can be modified by attaching a new cylindrical brace.

FIG. 4 is an example of a reinforcing member provided in a pipe material, (a) is a longitudinal sectional explanatory view of a side surface and a main part, and (b) is an exploded perspective explanatory view.
A new half-cylindrical cylindrical support member 8 is coated on the outer periphery of the existing support portion 6 or a new cylindrical brace 9 is coated on the outer periphery of the existing brace 71 and integrally formed by welding.
As shown in the explanatory view (a) of the side and longitudinal section, the new cylindrical support member 8 or the joint portion of the new cylindrical brace 9 is provided with backing rings 10 and 10 as shown in the AA section. The backing plates 11 are provided as shown in the B-B cross section.
Further, as shown in the CC cross section, a semicircular disk-like shape is maintained between the new cylindrical support member 8 and the existing support 6 or between the new cylindrical brace 9 and the existing brace 71. Guide rings 12 and 12 are provided.

As shown in the exploded perspective explanatory view (b), a guide ring 12 having a half-divided disk ring shape (having a notch at a portion where the backing plates 11 and 11 abut) is provided in advance.
Further, belt plate-like backing plates 11 and 11 are provided at the longitudinal joint portion along the longitudinal direction of the half cylinder, and the semi-short tube is provided at the circumferential joint portion along the circumferential direction of both end edges of the half cylinder. The backing rings 10 and 10 are provided.

Thus, by providing the strip-shaped backing plates 11 and 11 at the longitudinal joint portion of the half cylinder, and by providing the semi-short tubular backing rings 10 and 10 at the circumferential joint portion of the half cylinder, The cylindrical support member 8 or the joint portion of the new cylindrical brace 9 can be properly welded with proper alignment.
Further, these backing ring 10 and backing plate 11 are attached in advance to a joint portion of a new cylindrical support member 8 or a new cylindrical brace 9 at the factory, so that temporary assembly becomes easy at the time of assembly at the site. The parts can be reliably aligned.
Thus, by providing the backing ring 10 and the backing plate 11, the dimension setting and accuracy of the joint portion are improved and complete welding can be performed, so that an appropriate connection structure can be obtained.

A semicircular guide ring 12 is provided in the gap between the new cylindrical support member 8 and the existing internal support portion 6 and between the existing brace 71 and the new cylindrical brace 9 to maintain a predetermined distance and improve assembly accuracy. So, when installing the new half-cylinder member along the existing cylindrical shape at the site, it is easy to match with the existing member and can be easily assembled without shifting the center, so that repair work can be performed with high work efficiency. it can.
Further, the guide ring 12 is attached to each of the half cylindrical members of the new cylindrical support member 8 and the new cylindrical brace 9 in advance at the factory, thereby preventing torsion and ensuring an accurate half cylindrical shape. The shape can be maintained during transportation and assembly.

The seismic reinforcement structure for a leg of a spherical tank according to the present invention is not only for a spherical tank for which the durability of the leg is desired to be improved, but also for a leg of an elevated spherical tank for water supply and a monument for which improvement of the seismic performance is desired. It can also be applied to partial repairs.

1 Spherical tank
2 Leg structure
3 spherical shell (spherical shell plate)
4 connections 5 basics
6 Supporting part
61 Shape steel
7 Braces
71 Pipe brace
72 Tie Rod Brace
8 New cylindrical support member
9 New cylindrical brace
10 Back ring
11 Back plate
12 Guide ring

Claims (2)

From basic 5 for supporting a Tamakaratai 3 of spherical tank 1 the existing leading to Tamakaratai 3 leg structure 2 supports 6 and respective support portions 6 and the connecting portion 4 over the entire connecting portion 4 periphery A gap plate is provided from the outer surface, and a belt-like backing plate 11 is provided and welded to a longitudinal joint portion between the new half-divided cylindrical tubes divided into a plurality along the longitudinal direction . A semi-short tubular backing ring 10 is provided at a circumferential joint portion along the circumferential direction and welded to form a new cylindrical support member 8 integrally formed,
A gap is provided from the outer surface of the existing pipe braces 71, 71 provided between the existing support portions 6, 6 for supporting the spherical shell 3 of the spherical tank 1 from the outer surface thereof, along the longitudinal direction. A belt-like backing plate 11 is provided at the longitudinal joint portion of the new split cylindrical tubes divided into a plurality of pieces and welded, and the short joint is formed at the peripheral joint portion along the circumferential direction of the new half cylinder. A spherical tank leg seismic strengthening structure characterized in that a new cylindrical brace 9, 9 integrally formed by welding with a backing ring 10 is formed . A semicircle for maintaining the gap between the existing support 6 and the new cylindrical support member 8 and the gap between the existing pipe brace 71 and the new cylindrical brace 9 to improve the assembly accuracy. A plate-shaped guide ring ( 12) is provided, and the leg portion seismic reinforcement structure for a spherical tank according to claim 1 .