JP2016216904A - Method for reinforcing existing spherical tank having steel-pipe brace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcing method for earthquake resisting and the like, which enables execution of reinforcement work without stopping an operation or being subject to the restriction of the operation, in regard to an existing spherical tank having a steel-pipe brace.SOLUTION: A part of intersection of a long steel-pipe brace 3 and short steel-pipe braces 4a and 4b, and a connection part between a support 2 and the steel-pipe braces are partially filled with mortar 6, 11 and 26 while using fillers 3 and 17.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a method for reinforcing an existing spherical high pressure gas storage tank in which a steel pipe brace is attached to a support column supporting the tank.

  The brace structure of the spherical tank includes a steel pipe brace and a tie rod brace. These are required to have sufficient strength as a reinforcing material for earthquake resistance or the like. For high-pressure gas facilities, seismic design is required based on the High-Pressure Gas Safety Act and the Act on Ensuring the Safety of Liquefied Petroleum Gas and Optimization of Transactions, but it occurred on March 11, 2011 In light of accidents resulting from the Great East Japan Earthquake, the necessity of reviewing the strength of the braces has been recognized again.

  Among the braces mentioned above, for steel pipe braces, a part of the “Aseismic Design Standards for High Pressure Gas Facilities” related to the High Pressure Gas Safety Act has been revised (enforced as of January 1, 2014), and since the enforcement of the law As for the newly established spherical tank, the strength study on the intersection of steel pipe braces was newly stipulated. In addition, "required reinforcement" that does not require this strength study was newly defined by the partial revision of "Operation and Interpretation of Seismic Design Standards for High-Pressure Gas Facilities" (Effective on the same date as above).

  For spherical tanks newly established before the effective date of the partial revision of the above “High-Pressure Gas Equipment Seismic Design Standards”, conformity with the revised seismic design standards is not legally required, but The notice gives the seismic evaluation based on the seismic design standards and technical advice that seismic reinforcement should be carried out if necessary (2014140519 on May 21, 2014) No. 1 “Measures to improve earthquake resistance of existing high-pressure gas facilities”). As a more specific method, the operator shall make an earthquake-resistant evaluation based on the above-mentioned earthquake-resistant design standards. As a result, for facilities that are not considered to have sufficient earthquake resistance, It describes that a plan for measures for security between development and refurbishment should be formulated and reported to the prefecture.

  Examples of a method for reinforcing a steel pipe brace of a spherical tank that has already been installed (referred to as “existing spherical tank” in the present specification) include diaphragm reinforcement and penetration gusset reinforcement (see Non-Patent Documents 1 and 2).

  However, these reinforcement methods require construction involving the use of fire. Therefore, in many cases, such as existing spherical tanks are containers for storing combustible materials, it is not possible to reinforce the steel pipe braces during tank operation by these methods. That is, in these methods, it is necessary to stop the tank operation and perform the reinforcement work, and an economic loss due to the operation stop occurs.

  As a coping method that does not use fire, measures to lower the liquid level in the tank can be considered.

  However, even with this method, there is an unavoidable operational limitation due to a decrease in storage capacity.

  In addition, even if the existing spherical tank is not a container for storing flammable materials, reinforcement work that requires fire during tank operation is not desirable, and the above-mentioned diaphragm reinforcement and penetration gusset reinforcement are not suitable for installation of diaphragms during construction. Since the strength of the struts and steel pipe braces is expected to decline temporarily, it is necessary to stop the tank operation and perform reinforcement work.

  Furthermore, it is desirable to suppress the addition of a new burden to the existing spherical tank as much as possible. For example, when the weight of equipment after construction increases, the seismic force acting on it increases, the stress generated in each part increases, and the burden on the supporting foundation and ground must also be considered.

  Currently, for existing spherical tanks, as a means of reinforcement such as earthquake resistance, the tank operation is not stopped, the operation is not restricted, and the unnecessary burden on the equipment can be suppressed as much as possible. New methods are strongly desired.

Ministry of Economy, Trade and Industry Ministry of Economy, Trade and Industry

  The present invention has been made in view of the above problems, and for existing spherical tanks having steel pipe braces, it is possible to carry out reinforcement work such as earthquake resistance without stopping operation, and there are operational restrictions such as liquid level reduction. It is an object of the present invention to provide a method for reinforcement that does not receive the burden and does not cause an unnecessary burden on the facility.

  In an existing spherical tank with a steel pipe brace, high stress is generated because of the intersection of the steel pipe braces (long brace, which is a long steel pipe brace and short brace, which is a short steel pipe brace), the strut and the steel pipe brace. In view of the connection portion, it is effective and important that the reinforcement of strength such as earthquake resistance in the existing spherical tank is focused on these points.

As described above, according to the present invention, as a first aspect, a long brace, which is a long steel pipe brace, and a short brace, which is a short steel pipe brace, are attached to a column supporting a tank so as to cross each other. A method for reinforcing a spherical tank,
(A) A step of providing each column with a column first opening for injecting and filling a column mortar (lower mortar) inside the column below the column,
(B) Injecting the lower mortar from the first support column opening, and filling the lower mortar at a position inside the lower column and where the long brace or short brace is attached;
(C) closing the first support column opening;
(D) a step of providing each column with a column second opening for injecting and filling the column upper mortar (upper mortar) and a filler into the upper inside of the column;
(E) A filling material is placed on the lower mortar from the second column opening so that the upper mortar is disposed at the position inside the upper portion of the column and where the long brace or the short brace is attached. Injecting, and
(F) Injecting the upper mortar onto the filling from the support column second opening, and filling the upper mortar at the position described in (e),
(G) closing the support column second opening;
(H) a step of providing each long brace with a long brace opening for injecting a filling and mortar into the inside of each long brace;
(I) Filling the inside of the lower part of the long brace from the long brace opening so that the mortar is arranged inside the long brace and at a position where the long brace and the short brace intersect. Injecting things,
(J) Injecting mortar onto the filling from the elongated brace opening, and filling the mortar at the position described in (i);
(K) closing the long brace opening;
There is provided a method for reinforcing an existing spherical tank.

As a second aspect, the present invention provides an existing spherical shape in which a long brace that is a long steel pipe brace and a short brace that is a short steel pipe brace are attached to a support column that supports a tank so as to intersect each other. A tank reinforcement method,
(A) providing a column opening in each column;
(B) Injecting mortar from the support opening, and filling the lower mortar into the position inside the lower part of the support and where the long brace or the short brace is attached;
(C) injecting a filling material onto the lower mortar from the opening of the column so that the upper mortar is disposed at the position inside the upper column of the column and where the long brace or short brace is attached; ,
(D) injecting mortar over the filling from the support opening, and filling the upper mortar at the position described in (c);
(E) closing the column opening;
(F) providing each long brace long brace opening;
(G) The inside of the long brace is filled into the lower inner side of the long brace from the long brace opening so that the mortar is arranged at a position where the long brace and the short brace intersect. Injecting things,
(H) Injecting mortar onto the filling from the long brace opening, and filling the mortar at the position described in (g);
(I) closing the long brace opening;
There is provided a method for reinforcing an existing spherical tank.

  According to the reinforcing method of the present invention, construction can be performed without using fire, so that the existing spherical tank can be subjected to reinforcement work such as earthquake resistance during its operation.

  In addition, since the reinforcement work can be performed during the tank operation, the work can be performed regardless of the tank opening time. Reinforcement can be performed.

  Furthermore, in the method of the present invention, it is not necessary to change conditions such as storage tank capacity, so that there are no operational restrictions as in the liquid level lowering measure.

It is a figure which shows an example of the existing spherical tank which has a steel pipe brace. It is the figure which expanded and showed a part of the existing support | pillar of an existing spherical tank, and the existing steel pipe brace (long brace and short brace). It is a figure which shows the process in one Example of this invention. 3 to 11 are diagrams according to the same embodiment. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process in one Example of this invention. It is a figure which shows the process (at the time of completion) in one Example of this invention. It is a figure which shows the analysis object in a comparison experiment. It is a figure which shows the analysis object in a comparison experiment. It is a figure which shows the result (average stress in a steel pipe inner surface) of a comparison experiment. It is the schematic of mortar unfilling (Case 1), mortar partial filling (Case 2), and mortar full filling (Case 3).

  Hereinafter, an embodiment according to a method for reinforcing an existing spherical tank according to the present invention will be specifically described with reference to the drawings.

Example 1
FIG. 1 shows an example of an existing spherical tank 1 having a steel pipe brace. In such a spherical tank, a long brace 3 that is a long steel pipe brace and a short brace 4a and 4b that are short steel pipe braces are attached to a support column 2 that supports the tank. There is a space inside the column 2 and the long brace 3.

  FIG. 2 is an enlarged view of a part of the existing struts of the existing spherical tank and the existing steel pipe braces (long brace and short brace). As shown in FIG. 2, in the struts (2, 2) and the steel pipe braces (3, 4 a, 4 b) attached therebetween, there are four joint portions (A, B, C, D) between the struts and the steel pipe braces. There is one intersection (E) between the steel pipe braces (long brace and short brace). When shaking due to an earthquake or the like occurs, high stress is generated in these joint portions (A, B, C, D) and crossing portions (E) (Note that A to E in FIG. 2 roughly indicate positions where high stress occurs. Is shown). The reinforcing method of the present invention reinforces these joint portions / intersection portions and the periphery thereof in a concentrated manner. This reinforcement is realized by partially filling the inside (inside) of the support column and the long brace with mortar.

  The steps of the reinforcing method of the present invention are as follows.

  In the present invention, for all the support columns, the lower portion where the steel pipe brace is attached (around the locations indicated by A and B in FIG. 2 and its surroundings as appropriate) is reinforced from the inside of the support columns with mortar. Therefore, first, as shown in FIG. 3, the first support column 2 is provided with the first support column opening 5 for injecting and filling mortar into the lower inner side of each support column.

  If the mortar is dropped as it is from a high position, the components (mainly cement, water, fine aggregate) become non-uniform due to the impact of the drop, which may affect the performance after mortar setting. In the present embodiment, this problem is addressed by providing a first support column opening 5 closer to the lower column than a second support column opening, which will be described later, separately from the second support column opening.

  The method of the present invention can be applied even during tank operation, and this is one of the major features of the present invention. When the method of the present invention is used during tank operation, The opening work for providing the first support column opening 5 (the same applies to the opening work of other openings described later) is a method that does not use fire (for example, an air-driven drill or a hole saw, a steel pipe and a tooth of the drill or the hole saw). Use a special jig that does not expose the contact area. The first column opening, the second column opening described later, and the long brace opening calculate the appropriate shape, inner diameter, area, and the like in consideration of the strength of the columns and braces.

  The first support column opening 5 is located above (for example, filling the lower mortar 6 shown in FIG. 4) above a position where a lower mortar (also referred to as a “lower mortar” or “lower mortar” in this specification) is filled. It shall be provided within about 1 m upward from the upper end 7 of the range.

  Next, mortar for the lower part is injected from the first support opening 5 of the support, and a position inside the lower part of the support 2 and one end of the long brace 3 and the short brace 4b is attached (at B and A in FIG. 2). Fill the lower mortar around the indicated location and its surroundings as appropriate.

  FIG. 4 shows a state after the lower mortar 6 is filled. The range of filling includes a range 18 from the inner bottom end 8 of the support column 2 to at least the upper end 9 of the portion where the long brace 3 and the short brace 4b are joined to the support column 2 (at least this range covers the cover). In view of effectively reinforcing the strength, it is preferable to fill beyond this range as appropriate to the upper side.

  The injection of the lower mortar from the first support column opening 5 can be performed through a hose or a pipe (the same applies to the injection of mortar and filler described below).

  The mortar for the lower part (the same applies to the mortar other than the lower part) may be injected in an amount calculated in advance, may be injected while visually observing, or may be performed by both of them. In the case of visual observation, a visual opening is appropriately provided in the support (closed after the work is completed).

  The mortar for the lower part used in the present invention (same for mortars other than the lower part) is mainly manufactured by mixing cement, water, and fine aggregate, and a general one can be used. Non-shrink mortar that does not cause drying shrinkage even after curing is preferred.

  The mortar is in the form of a slurry at the time of production or pouring, but solidifies with the passage of time and adheres to or adheres to the inside of the column. Thereby, the mortar filling location is reinforced.

  After filling the lower mortar 6, the first column opening 5 provided in each column 2 is closed. Closing can be performed using a screwed plug or the like. For example, using a washer having a surface that matches the outer periphery curvature of the support column 2 and sealing with a hexagon bolt or bolt / nut is preferable because the contact surface between the support column and the closing member can be increased and the member can be firmly closed. The state after closing the first support column opening 5 is indicated by a broken line in FIG.

  Reinforcement of the strut is also in the vicinity of the upper part where the steel pipe brace is attached, that is, the position where the long brace and the short brace are attached (locations indicated by C and D in FIG. 2 and its surroundings as appropriate) Reinforce by filling and placing mortar inside the column. Therefore, as shown in FIG. 5, the existing support column 2 is provided with a support column second opening 10 for injecting and filling the support column top mortar (upper mortar) into the upper part of the support column.

  The support column second opening 10 is located above the position where the upper mortar (and filling material described later) is filled (for example, about 1 m upward from the upper end 12 of the filling range of the upper mortar 11 shown in FIG. 7). Shall be provided.

  Here, in the present invention, the filling material is first injected from the second support column opening 10.

  As described above, high stress is generated in the existing spherical tanks with steel pipe braces because the steel pipe braces (long braces, which are long steel pipe braces, and short braces, which are short steel pipe braces), struts and struts. And steel pipe brace connection. Therefore, it is effective to reinforce strength by filling mortar with emphasis on these places.

  On the other hand, when the mortar is filled beyond these locations, the seismic force acting on the spherical tank increases as the weight increases, and the stress generated in the struts, braces and base plate of the spherical tank increases. In addition, as the weight increases, the burden on the foundation and ground supporting the spherical tank also increases. In order to minimize the burden on the spherical tank, foundation and ground, it is not desirable to fill the mortar beyond the necessary part.

For example, when comparing Case 2 (partial filling of mortar according to the present embodiment) described later and a case (Case 3) in which the filling portion of Case 2 is filled with the same mortar instead of filling. (Note that the tank capacity is 3000 m ³ , the number of support columns is 12, the weight of the tank before reinforcement is about 390 tons, the specific gravity of the mortar is 2.40 ton / m ³ , and the specific gravity of the packing is 0.09 ton / m ³ ), When the total volume of the mortar and the filler filled in the long brace is 2.097 m ³ and the total weight is about 12.660 tons, in Case 3, the total volume of the mortar filled in the column and the long brace is the same. 2.097 m ³ , but the total weight is about 60.423 tonnes. In this case, the tank's own weight increases by about 16% in Case 3 (full mortar filling) compared to the case without mortar filling (Case 1), whereas the increase in Case 2 (invention) is about Only 3%. A schematic diagram of Case 1, Case 2 and Case 3 is shown in FIG.

  As described above, the mortar is mainly manufactured by mixing cement, water, and fine aggregate, and immediately after mixing, it is in a slurry state, approaches a solid as time passes, and finally becomes a solid. Since the mortar is injected in the form of a slurry, it flows downward due to its own weight. As a result, the mortar stays at the inner lower part of the support and the inner lower part of the brace, and partial filling of the mortar into the support upper part and the brace connecting part cannot be realized.

  From the above, in order to partially fill the upper portion of the support and the brace with the mortar, a structure for supporting the slurry-like mortar is required. As a structure for this support, in the present invention, a filler is filled.

  That is, in order to reinforce mainly these portions by partially filling the upper mortar around the position where the long brace or short brace is attached inside the upper part of each column, the lower mortar 6 filled first is After curing, the filler is injected from the second support opening 10 toward the lower mortar 6.

  FIG. 6 shows a state after the column 2 is filled with the filler 17. The filling is performed so that the upper mortar 11 described later is filled in an appropriate position. The upper mortar 11 needs to be filled at least in a range 13 that covers a portion where one end of the long brace 3 and the short brace 4a is joined to the support 2 and is to reinforce the strength effectively. In consideration of the above, it is preferable to fill the region 13 beyond this range 13 and to a wider range as appropriate (both the upper end 14 and the lower end 15 of this range 13). Therefore, it is preferable to fill the filler so that the lower end 16 (see FIG. 7) of the upper mortar 11 is located slightly below the lower end 15 of the range 13.

  The filling material in the present invention (including not only the one injected into the support column but also the one injected into the long brace) does not adhere to the inside of the support column or brace as the mortar filled on the packing is cured. The mortar can be supported until it is fixed, and it must be nonflammable. A relatively light weight is preferred. From this point of view, for example, granular pearlite can be used as the filler.

  The filling may be injected in a pre-calculated amount, may be injected while visually observing, or may be performed by both of them. In the case of visual observation, a visual opening is appropriately provided in the support (closed after the work is completed).

  If a new tank is installed (before the tank is in operation), or if the existing spherical tank is stopped and the steel brace is replaced with another one (use fire for this replacement work). It is necessary to stop the operation of the tank), and it is also conceivable that the mortar can be partially filled by a method such as providing a partition in the support column or brace. However, it is impossible to use the above method while continuing operation in the existing spherical tank, because it is essential to use fire for replacement work, and it will not be possible to keep the current strength. .

  After filling the filling material, the mortar for the upper part is injected from the second opening 10 of the support column onto the filling material 17, and the positions where the long brace 3 and the short brace 4 a are attached (C and D in FIG. 2). The upper mortar is filled around the area indicated by. The upper mortar solidifies over time and adheres to the inside of the support column 2. Thereby, the mortar filling location of the support | pillar 2 is reinforced.

  As described above, the upper mortar 11 needs to be filled in a range 13 that covers at least a portion where one end located at the upper part of the long brace 3 and the short brace 4a is joined to the support column 2, but the strength is effectively increased. In consideration of reinforcement, it is preferable to fill the region 13 beyond this range 13 and to a wider range as appropriate (both the upper end 14 and the lower end 15 of this range 13). FIG. 7 shows a state after the upper mortar 11 is filled.

  After filling the upper mortar 11, the column second openings 10 provided in the columns are closed. The closing in this case can also be performed using a screwed plug or the like. Further, for example, using a washer having a surface that matches the outer periphery curvature of the column and sealing with a hexagon bolt or bolt / nut is preferable because the contact surface between the column and the closing member is increased and the column can be firmly closed. The state after the support column second opening 10 is closed is indicated by a broken line in FIG.

  Furthermore, the steel pipe brace is reinforced. This reinforcement is performed by filling the inside of the long brace with mortar at the position where the long brace and the short brace intersect (around the portion indicated by E in FIG. 2 and its surroundings as appropriate).

  Therefore, as shown in FIG. 8, long brace openings 19 for injecting and filling mortar into the long braces are provided in each existing long brace 3.

  The long brace opening 19 is provided above the position where the mortar (and filling material described later) is filled (for example, from the upper end 20 of the mortar filling range shown in FIG. 10 to the top within about 1 m in the vertical direction). .

  From the long brace opening 19, a filler is first injected. This filler is filled inside the long brace so that the mortar is arranged at a position where the long brace and the short brace intersect (around the position indicated by E in FIG. 2 and its surroundings as appropriate). It is what is done. The details of the filling material to be filled here are the same as those for the filling material to be filled in the above-mentioned struts.

  FIG. 9 shows a state after the long brace 3 is filled with the filler 21. The long brace is filled from the lowermost part of the brace so that the mortar is filled in an appropriate position as described later. The mortar filled in the long brace needs to be filled in a range 22 that covers at least a portion where the long brace 3 and the short braces 4a and 4b intersect (a portion indicated by E in FIG. 2). In consideration of effectively reinforcing the strength, it is preferable to fill the region beyond this range 22 and to a wider range as appropriate (both the upper end 23 and the lower end 24 of this range 22). Therefore, the filling material 21 is preferably filled so that the lower end 25 (see FIG. 10) of the mortar is positioned slightly below the lower end 24 of the range 22.

  After the filling material 21 is filled, mortar is injected from the long brace opening 19 onto the filling material 21, and the position where the long brace 3 and the short braces 4a and 4b intersect (location shown by E in FIG. 2) The mortar 26 is filled in and around the periphery as appropriate. This mortar solidifies over time and adheres to the inside of the long brace 3. Thereby, the mortar filling location is reinforced.

  As described above, the mortar 26 needs to be filled in a range 22 (see FIG. 9) that covers at least a portion where the long brace 3 and the short braces 4a and 4b intersect (a portion indicated by E in FIG. 2). However, considering that the strength is effectively reinforced, it is preferable to fill the range beyond this range 22 (with the upper end 23 and the lower end 24 of this range 22) as appropriate. FIG. 10 shows a state after the long brace 3 is filled with the mortar 26.

  After mortar filling, the long brace opening 19 provided in each long brace is closed. In FIG. 11, a state in which the long brace opening 19 is closed is indicated by a broken line. The closing in this case can also be performed using a screwed plug or the like. Further, for example, using a washer having a surface that matches the outer periphery curvature of the column and sealing with a hexagon bolt or bolt / nut is preferable because the contact surface between the column and the closing member is increased and the column can be firmly closed.

  FIG. 11 illustrates a state in which reinforcement by the method of the present invention is completed. All the struts and steel pipe braces of the existing spherical tank to be reinforced are in the state shown in the figure.

(Comparative experiment)
In order to reduce the stress generated in each part by filling the brace intersection and strut / brace joint (connection part) with mortar, a 3000m ³ spherical tank is used as a model, Case 1 (unfilled mortar), Case 2 cases (partial filling of mortar), “2012 Ministry of Economy, Trade and Industry commissioned oil refining industry security measures project (Survey on response to earthquakes and tsunamis at high-pressure gas handling facilities) (1) Examination of earthquakes at high-pressure gas equipment Study of strength evaluation method of 1 brace The average stress generated in each part was calculated according to the method shown in the report (February 2013, High Pressure Gas Safety Association).

The analysis conditions are as follows.
Applicable regulations: High-pressure gas safety law Nominal capacity: 3000 m ³
Content liquid filling rate: 90%
Upper support specifications: φ558.8 × 9.5 t (ACE60H)
Lower column specifications: φ558.8 × 9.5 t (STK41)
Brace specifications: φ267.4 × 8.0 t (STK41)
Tank weight: 3,550 kN
Contents liquid weight: 13,490.8 kN
Snow cover weight: 250 kN
Importance: Ia (β1 = 1.0)
Regional classification: B (β2 = 0.6)
Ground type: Three types of ground (β3 = 2.0)
Tank center of gravity position from bottom of base plate: 10,560mm
Horizontal seismic force: 7,654.69 kN
Vertical seismic force: 20,403.2 kN
Material properties: see Table 1

  The mortar used was a non-shrink mortar mixed with cement, water and sand, and the filler used was pearlite.

  In Case 2, the mortar and the filler were filled by the method of Example 1 of the present invention. The first support column opening, the second support column opening, and the long brace opening were each provided at a position 50 cm upward from the upper end of the mortar filling range, and were closed using a screwed plug after filling. Moreover, the lower mortar of the support was filled up to a position of 50 mm upward from the upper end of the joint part of the brace. The upper mortar of the support was filled from the position of 50 mm downward from the lower end of the joint of the brace to the position of 50 mm upward from the upper end of the joint. The mortar of the long brace was filled from a position 50 mm downward from the lower end of the intersection with the short brace to a position 50 mm upward from the upper end of the intersection.

  The analysis object is shown in FIGS.

Table 1 Material properties

  The analysis results (1) and (2) are as follows.

Table 2 shows the average stress and stress reduction rate of each part. FIG. 14 shows the average stress on the inner surface of the steel pipe where the stress is the largest when the respective parts are compared. In addition, in Table 2, the average stress of the brace intersection between the support No. 6 and No. 7 strut / brace joints and the support No. 6 and No. 7 in which the maximum axial force is generated in the brace is shown. The following findings were obtained.
(1) In Case 2 (mortar partially filled case), a stress reduction of about 70% at the maximum is confirmed at the brace intersection compared to Case 1 (mortar unfilled case).
(2) In Case 2, compared to Case 1, a maximum stress reduction of about 65% is confirmed at the strut / brace joint.
(3) From (1) and (2) above, it was confirmed that the generated stress could be reduced by filling the brace intersection and the strut / brace junction with mortar.

Table 2 Average stress and stress reduction rate of each part

(Example 2)
In Example 1, although it has comprised so that the opening part for inject | pouring mortar and a filler into a support | pillar may be provided twice (a support | pillar 1st opening part and a support | pillar 2nd opening part), this opening part is made into one. You can also

  That is, in each strut 2, from the position around the place where the long brace 3 and the short braces 4a and 4b are attached (the place shown by C and D in FIG. 2) at the top of the strut 2 and the upper mortar 11 is filled. Further, a column opening is provided above (for example, the position of the column second opening 10 in FIG. 5), and each column has a mortar for lower column (lower mortar) 6 and a filler 17 on the inner side of the column 2 from this one position. , And mortar for upper part of support (upper mortar) 11 may be injected and filled.

  In this case, there is a certain distance between the column opening and the position where the lower mortar 6 is filled. However, if the mortar is dropped from a high position, the components (mainly cement, water, fine bones) are caused by the impact of the drop. For example, when filling the lower mortar, insert the hose long from the opening of the column to the inside of the column and fill the tip of the hose. Can be arranged in the vicinity of the lower mortar filling location, and the lower mortar can be injected through a hose.

  According to the method of the present invention, it is possible to perform reinforcement work without using fire and without temporarily reducing the existing strength. For this reason, it is possible to perform seismic reinforcement work during the operation of the existing spherical tank, and it is possible to avoid loss due to operation stop.

  In addition, according to the method of the present invention, since the reinforcement work can be performed during the tank operation, the work can be performed regardless of the tank opening time, and compared with the case where the operation is stopped and the work is performed during the opening period. In this way, reinforcement such as earthquake resistance can be performed at an early stage.

  Furthermore, in the method of the present invention, it is not necessary to change conditions such as storage tank capacity, so that there are no operational restrictions as in the liquid level lowering measure.

  Not only that, the method of the present invention is an intersection of steel pipe braces (a long brace that is a long steel pipe brace and a short brace that is a short steel pipe brace) that generate high stress in an existing spherical tank having a steel pipe brace. Reinforcement is intensively performed on the connection part between the support part and the column and the steel pipe brace. In addition, the construction does not require complicated processes or large-scale equipment and instruments. Therefore, according to the method of the present invention, it is possible to efficiently and effectively reinforce the strength and to reduce the construction cost.

  Thus, the industrial applicability of the present invention is extremely high.

DESCRIPTION OF SYMBOLS 1 Existing spherical tank 2 Prop 3 Long braces 4a, 4b Short brace 5 Prop 1st opening 6 Lower mortar (lower mortar)
7 Upper end of lower mortar filling range 8 Inner lowermost end 9 of column 2 Upper end of a portion where long brace 3 and short brace 4b are joined to column 2 Column second opening 11 Upper mortar 12 Upper mortar 11 filling range Upper end 13 Covering the portion where the upper ends of the long brace 3 and the short brace 4a are joined in the support column 2 The upper end 15 of the range 13 The lower end of the range 13 The lower end 16 of the upper mortar filling range 17 The filling 18 of the support 2 Range from the innermost lower end 8 to the upper end 9 of the portion where the long brace 3 and the short brace 4b are joined to the support 2 19 long brace opening 20 upper end 21 of the mortar filling range of the long brace filling 22 long Range 23 covering the intersection of brace 3 and short braces 4a and 4b Upper end 24 of range 22 Lower end of range 22 Lower end of mortar 26 Mortar A, B, C, D Joint part of strut and steel pipe brace (long brace or short brace) E Intersection part of steel pipe braces (long brace and short brace)

Claims (2)

A method of reinforcing an existing spherical tank in which a long brace that is a long steel pipe brace and a short brace that is a short steel pipe brace are attached to a support column that supports the tank,
(A) A step of providing each column with a column first opening for injecting and filling a column mortar (lower mortar) inside the column below the column,
(B) Injecting the lower mortar from the first support column opening, and filling the lower mortar at a position inside the lower column and where the long brace or short brace is attached;
(C) closing the first support column opening;
(D) a step of providing each column with a column second opening for injecting and filling the column upper mortar (upper mortar) and a filler into the upper inside of the column;
(E) A filling material is placed on the lower mortar from the second column opening so that the upper mortar is disposed at the position inside the upper portion of the column and where the long brace or the short brace is attached. Injecting, and
(F) Injecting the upper mortar onto the filling from the support column second opening, and filling the upper mortar at the position described in (e),
(G) closing the support column second opening;
(H) a step of providing each long brace with a long brace opening for injecting a filling and mortar into the inside of each long brace;
(I) Filling the inside of the lower part of the long brace from the long brace opening so that the mortar is arranged inside the long brace and at a position where the long brace and the short brace intersect. Injecting things,
(J) Injecting mortar onto the filling from the elongated brace opening, and filling the mortar at the position described in (i);
(K) closing the long brace opening;
A method for reinforcing an existing spherical tank, comprising:
A method of reinforcing an existing spherical tank in which a long brace that is a long steel pipe brace and a short brace that is a short steel pipe brace are attached to a support column that supports the tank,
(A) providing a column opening in each column;
(B) Injecting mortar from the support opening, and filling the lower mortar into the position inside the lower part of the support and where the long brace or the short brace is attached;
(C) injecting a filling material onto the lower mortar from the opening of the column so that the upper mortar is disposed at the position inside the upper column of the column and where the long brace or short brace is attached; ,
(D) injecting mortar over the filling from the support opening, and filling the upper mortar at the position described in (c);
(E) closing the column opening;
(F) providing a long brace opening in each long brace;
(G) The inside of the long brace is filled into the lower inner side of the long brace from the long brace opening so that the mortar is arranged at a position where the long brace and the short brace intersect. Injecting things,
(H) Injecting mortar onto the filling from the long brace opening, and filling the mortar at the position described in (g);
(I) closing the long brace opening;
A method for reinforcing an existing spherical tank, comprising:

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