JP2018193815A - Reinforced building and method for producing the same - Google Patents

Abstract

To easily reinforce an intermediate layer of an existing building at a low cost.SOLUTION: A reinforced building 1 includes an existing building 10, and a reinforcement structure 20 for reinforcing the existing building 10. The reinforcement structure 20 includes a reinforcement column 21 arranged along a column 11 of the existing building 10, a reinforcement beam 22 arranged along a beam of the existing building 10, and a reinforcement intersection 23 disposed at a location corresponding to an intersection 13 of the existing building 10. The reinforcing column 21 and the reinforcing beam 22 include a concrete hardened body with rebar embedded therein. The reinforcement intersection 23 includes a polymer cement mortar hardened body with the rebar embedded therein. A cutout 12A is provided in a corner on an upper end side and an outer surface side of the existing building 10 of the beam 12. The concrete hardened body is fitted in the cutout 12A, and thereby, the reinforcement beam 22 is supported by the beam 12.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to a reinforced building and a method for manufacturing the same.

  In recent years, various construction methods have been proposed in order to improve the earthquake resistance of existing buildings. Non-Patent Document 1 discloses a method for manufacturing a reinforcing structure that simply and inexpensively reinforces an existing building. The method includes a step of arranging a reinforcing bar at a position corresponding to a column part, a beam part, and an intersection part on the outer wall surface side of an existing building, and a first formwork configured in a part corresponding to the column part of the reinforcing bar A step of placing concrete in the inside and a second formwork formed in a part of the reinforcing bar corresponding to the beam part, and a third formwork configured in the part of the reinforcing bar to be an intersection Filling the inside with polymer cement mortar. The compressive strength of the mortar hardened body in which the polymer cement mortar is hardened is larger than the compressive strength of the hardened concrete body in which the concrete is hardened.

"Summary Report on Building Technology Performance Certification Evaluation Design U Frame Method-Seismic Strengthening Method Using External RC Frame-", Japan Building Research Institute, GBRC Performance Certification No. 13-27

  By the way, for example, in an existing high-rise building (existing building on the 10th to 15th floors), the lower layer part is composed of a steel reinforced concrete structure (SRC structure), and the upper layer from the middle layer part (for example, the vicinity of the sixth floor). It may be composed of reinforced concrete structure (RC structure). That is, in the intermediate layer portion, the structure type may be switched from SRC construction to RC construction. The lower layer portion of SRC structure may have sufficient seismic performance compared with the earthquake resistance performance of the intermediate layer portion of RC structure. When reinforcing such an existing building and constructing a reinforcing structure from the first floor portion of the existing building, the lower layer portion having sufficient strength is also reinforced before the intermediate layer portion is reinforced. Therefore, the construction of a reinforcing structure for the lower layer can be a factor in increasing costs and prolonging the construction period.

  Therefore, the present disclosure describes a reinforced building capable of easily and inexpensively reinforcing an intermediate layer portion of an existing building and a manufacturing method thereof.

  [1] A reinforced building according to one aspect of the present disclosure includes an existing building and a reinforcing structure that reinforces the existing building. The existing building is located at the intersection of the column part including the reinforcing bar, the beam part including the reinforcing bar, the column part and the beam part, and connected to the end of the column part and the end of the beam part, respectively. And having an intersection. The reinforcing structure is disposed along the column and includes a reinforcing column including a hardened concrete body in which a reinforcing bar is embedded, and a reinforcing beam including a hardened concrete body that is disposed along the beam and embedded in the reinforcing bar. And a reinforcing intersection including a polymer cement mortar hardened body in which a reinforcing bar is embedded and is connected to the end of the reinforcing column and the end of the reinforcing beam, respectively, at a position corresponding to the intersection. A notch is provided at a corner on the upper edge side of the beam portion and on the outer surface side of the existing building. The reinforcing beam part is supported by the beam part by locking the hardened concrete body to the notch part.

  In the reinforced building which concerns on one viewpoint of this indication, the reinforcement beam part is supported by the beam part by being latched by the notch part. Therefore, the notch part of the beam part functions like a hook that hooks the reinforcing beam part against the existing building, so that the reinforcing beam part is supported with respect to the existing building and a large shear resistance is generated in the notch part. Demonstrated. Therefore, since the weight of the reinforcing beam portion is transmitted to the beam portion very reliably through the notch portion, it is possible to reconstruct the existing building requiring reinforcement without constructing the reinforcing beam portion with respect to the lower layer portion of the existing building. Reinforcement can be performed on the intermediate layer portion. As a result, it is possible to easily and inexpensively reinforce the intermediate layer portion of the existing building.

  [2] In the reinforced building described in the above item 1, the notch is located at the end of the beam and may be separated from the intersection adjacent to the notch. Here, when a horizontal external force acts on the reinforced building due to the occurrence of an earthquake or the like, the existing building is likely to be broken at the connection portion between the beam portion and the intersection portion. For this reason, if the notch is separated from the adjacent intersection, it is difficult to cause a reduction in the cross-sectional area in the portion of the beam that is prone to breakage. Therefore, sufficient strength of the beam portion can be ensured.

  [3] In the reinforced building described in the above item 2, the inner edge of the notch is located on both ends of the beam provided with the notch from the intersection adjacent to the notch. You may be located in the range to the length of 1/3 of the internal method of a pillar part. Since the beam part of the existing building supports the weight of the floor, wall, etc. for a long time, the central part of the beam part is particularly easily bent. Therefore, if the notch is provided at the center of the beam, the beam may be greatly bent. However, according to the reinforced building described in the third item, the inner edge of the notch is located away from the center of the beam. Therefore, it is difficult for the portion where the reinforcing beam portion is supported by the beam portion to bend. Therefore, it is possible to sufficiently secure the supporting force of the reinforcing beam portion by the beam portion.

  [4] In the reinforced building described in the above item 2 or 3, the length of the notch in the horizontal direction may be 1/50 to 1/4 of the length of the beam. If the length of the notch in the horizontal direction is 1/50 or more of the length of the beam, the portion of the hardened concrete of the reinforcing beam that is located in the notch is firmly locked by the notch. Tend to be. If the length of the notch in the horizontal direction is ¼ or less of the length of the beam, the notch is positioned closer to the end rather than the center of the beam, so the long-term relative to the center of the beam Tend to be smaller.

  [5] In the reinforced building according to any one of items 1 to 4, the vertical height of the notch is 50 mm or more and 1/2 or less of the beam formation of the beam. There may be. If the height in the vertical direction of the notch portion is 50 mm or more of the beam portion of the beam portion, the portion located in the notch portion of the hardened concrete body of the reinforcing beam portion is firmly locked by the notch portion. There is a tendency. If the height in the vertical direction of the notch is less than or equal to 1/2 the beam formation of the beam, the size of the portion of the beam located below the notch is sufficiently secured, so the weight There is a tendency that the reinforcing beam part which is an object is firmly supported by the beam part.

  [6] In the reinforced building according to any one of Items 1 to 5, the corner portion of the notch portion may be recessed downward. In this case, the part located in the notch portion of the hardened concrete body of the reinforcing beam portion is likely to bite into the notch portion. Therefore, the reinforcing beam portion can be more reliably supported with respect to the existing building.

  [7] In the reinforced building according to any one of the above items 1 to 6, the reinforced structure further includes a connecting member that is inserted through both the beam portion and the reinforcing beam portion. May be. In this case, the beam portion and the reinforcing beam portion are integrated via the connection member. Therefore, since the weight of the reinforcing structure is transmitted to the beam portion via the connection member, the reinforcing beam portion can be more reliably supported with respect to the existing building.

  [8] In the reinforced building according to any one of Items 1 to 6, the reinforced structure may further include a metal plate positioned between the notch and the reinforcing beam. Good. In this case, since the notch is reinforced by the metal plate, a greater shear resistance can be obtained at the notch.

  [9] In the reinforced building described in the above item 8, the reinforced structure further includes a connection member inserted into both the beam portion and the reinforcement beam portion, and the connection member is provided on the metal plate. It may be inserted through the formed through hole. In this case, the beam portion, the reinforcing beam portion, and the metal plate are integrated via the connection member. Therefore, since the weight of the reinforcing structure is transmitted to the beam portion via the connection member and the metal plate, the reinforcing beam portion can be more reliably supported with respect to the existing building. Moreover, since the notch is reinforced by the metal plate, a greater shear resistance can be obtained at the notch.

  [10] In the reinforced building described in the above item 8 or 9, the metal plate may be provided with a fixing member extending in the reinforcing beam portion. In this case, the concrete hardened body of the reinforcing beam portion and the metal plate are integrated via the fixing member. Therefore, since the weight of the reinforcing structure is transmitted to the beam portion via the fixing member and the metal plate, the reinforcing beam portion can be more reliably supported with respect to the existing building.

  [11] A method for manufacturing a reinforced building according to another aspect of the present disclosure includes a column part, a beam part including a reinforcing bar inside, a column part and an end part of the column part at a position where the beam part intersects And a method of manufacturing a reinforced building in which an existing building is reinforced by a reinforcing structure by providing a reinforcing structure in an existing building having an intersection connected to each end of the beam, A first step of forming a notch by rolling the corner on the outer surface side of the existing building on the upper edge side, and a position corresponding to each of the column portion, the beam portion, and the intersection after the first step A second step of arranging the reinforcing bars in the first step, and after the second step, providing the first mold so as to cover the reinforcing bars arranged in the pillar portion, and placing concrete in the first mold After the third step of forming the reinforcing column portion by the second step and the second step, the second step is performed so as to cover the reinforcing bars arranged in the beam portion. A fourth step of forming a reinforcing beam part by placing concrete in the second mold form while filling the notch part, and placing it at the intersection after the second step A third mold is formed so as to cover the reinforcing bars, and a fifth step of forming a reinforcing intersection by filling the third mold with polymer cement mortar. The manufacturing method of the reinforced building which concerns on the other example of this embodiment has an effect similar to the reinforced building which concerns on the said 1st term.

  [12] In the method described in the above item 11, the notch is located at the end of the beam and may be separated from the intersection adjacent to the notch. In this case, the same effect as the reinforced building according to the second item can be obtained.

  [13] In the method described in [12] above, the inner edge of the notch portion is a column portion located on both ends of the beam portion where the notch portion is provided from the intersection adjacent to the notch portion. It may be located within a range up to 1/3 of the inner method. In this case, the same effect as the reinforced building according to the third item can be obtained.

  [14] In the method described in the above item 12 or 13, the length of the notch in the horizontal direction may be 1/50 to 1/4 of the length of the beam. In this case, the same effect as the reinforced building according to the fourth item can be obtained.

  [15] In the method according to any one of the above items 11 to 14, the height in the vertical direction of the notch is not less than 50 mm and not more than ½ of the beam formation of the beam. Also good. In this case, the same effect as that of the reinforced building according to the fifth aspect can be obtained.

  [16] In the method according to any one of Items 11 to 15, the corner portion of the notch portion may be recessed downward. In this case, the same effect as that of the reinforced building according to the sixth aspect can be obtained.

  [17] The method according to any one of the above items 11 to 16, wherein the connecting member is arranged so that the tip portion is located outside after the first step and before the fourth step. The method further includes a sixth step of attaching the base end portion in the beam portion. In the fourth step, a second mold is provided so as to cover the reinforcing bars arranged in the beam portion and the distal end portion of the connection member, and a notch The reinforcing beam portion may be formed by placing concrete in the second formwork while filling. In this case, the same effect as that of the reinforced building according to the seventh aspect can be obtained.

  [18] The method according to any one of Items 11 to 16 includes a sixth step of attaching a metal plate to the notch after the first step and before the fourth step. In addition, in the fourth step, a second mold is provided so as to cover the reinforcing bars and the metal plate arranged in the beam portion, and concrete is placed in the second mold while filling the notch. Thus, the reinforcing beam portion may be formed. In this case, the same effect as that of the reinforced building according to the eighth item can be obtained.

  [19] In the method according to the nineteenth aspect described above, the base end portion of the connecting member is attached to the beam portion so that the distal end portion is located outside after the first step and before the fourth step. 7, and in the fourth step, the reinforcing member disposed in the beam portion, the tip of the connecting member, and the metal plate are covered with the connecting member inserted through the through hole provided in the metal plate. A reinforcing beam portion may be formed by providing a second mold and placing concrete in the second mold while filling the notch. In this case, the same effect as that of the reinforced building according to the ninth item can be obtained.

  [20] In the method described in the above item 18 or 19, the metal plate is provided with a fixing member, and in the fourth step, the second mold frame covers the fixing member, and the fixing member is You may extend in the reinforcement beam part. In this case, the same effect as the reinforced building according to the tenth aspect can be obtained.

  According to the reinforced building and the manufacturing method thereof according to the present disclosure, it is possible to easily and inexpensively reinforce the intermediate layer portion of the existing building.

FIG. 1 is a perspective view showing an example (first example) of a reinforced building in which a reinforced structure is constructed in an existing building. FIG. 2 is a front view schematically showing a part of FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view of another example (second example) of a reinforced building cut in the same manner as FIG. FIG. 5 is a cross-sectional view of another example (third example) of a reinforced building cut in the same manner as FIG. FIG. 6 is a front view schematically showing a part of another example (fourth example) of a reinforced building. FIG. 7 is a front view schematically showing a part of another example (fifth example) of the reinforced building.

  Since the embodiment according to the present disclosure described below is an example for explaining the present invention, the present invention should not be limited to the following contents. In the following description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

<Configuration of reinforced building>
With reference to FIGS. 1-3, the structure of the reinforced building 1 which concerns on this embodiment is demonstrated. The reinforced building 1 is obtained by constructing a reinforced structure 20 on an existing building 10. The existing building 10 includes a column part 11, a beam part 12, an intersection part 13, an outer wall 14, a window 15, and a slab part (not shown). The column part 11, the beam part 12, the intersection part 13, and the slab part are comprised, for example by reinforced concrete.

  For example, as shown in FIG. 3, the beam portion 12 is configured by embedding a reinforcing bar R1 in a hardened concrete body. The reinforcing bar R1 includes a plurality of main bars R1a extending in the extending direction of the beam portion 12, and a plurality of shear reinforcing bars R1b attached to the plurality of main bars R1a so as to surround the plurality of main bars R1a.

  The column portion 11 is provided on a base portion (not shown) and extends along the vertical direction. The beam part 12 is arrange | positioned between the adjacent pillar parts 11, and extends along a horizontal direction. Therefore, the assembly in which the column part 11 and the beam part 12 are assembled has a lattice shape. The column portion 11 and the beam portion 12 have, for example, a rectangular column shape having a rectangular cross section. The thickness (depth) of the column part 11 may be about 400 mm to 1000 mm. The width of the column part 11 may be about 400 mm to 1000 mm. The thickness (depth) of the beam portion 12 may be, for example, about 200 mm to 500 mm. The width of the beam portion 12 may be about 500 mm to 1200 mm.

  The intersection part 13 is a part located in the location where the pillar part 11 and the beam part 12 cross | intersect. The intersecting portion 13 also functions as a part of the column portion 11. The outer wall 14 extends along the vertical plane between the column part 11 and the beam part 12. The window 15 is provided in a region surrounded by the pillar portion 11 and the beam portion 12 in the outer wall 14.

  The slab part extends along the horizontal plane between the column part 11 and the beam part 12. The slab part functions as a floor and a ceiling. In addition, the existing building 10 illustrated by FIG. 1 is a 9-story building.

  The reinforcing structure 20 is provided on the outer wall surface of the existing building 10. The reinforcing structure 20 includes a reinforcing column part 21, a reinforcing beam part 22, a reinforcing intersection part 23, and a connection member 30. The reinforcing column part 21, the reinforcing beam part 22, and the reinforcing intersection part 23 have, for example, a rectangular column shape having a rectangular cross section.

  The reinforcing column part 21 is arranged on the outer wall surface of the existing building 10 and at a position corresponding to the column part 11. The reinforcing column part 21 extends along the same direction as the extending direction of the column part 11. In the example shown in FIG. 1, the reinforcing column portion 21 extends along the vertical direction between the fifth floor and the seventh floor of the existing building 10. The thickness (depth) of the reinforcing column part 21 may be, for example, about 350 mm to 600 mm. The width of the reinforcing column portion 21 may be about 500 mm to 800 mm.

  The reinforcing beam portion 22 is disposed on the outer wall surface of the existing building 10 and at a position corresponding to the beam portion 12. The reinforcing beam portion 22 extends along the same direction as the extending direction of the beam portion 12. That is, the reinforcing beam portion 22 extends along the horizontal direction. The reinforcing beam portion 22 is located between the reinforcing column portions 21 adjacent in the horizontal direction. The thickness (depth) of the reinforcing beam portion 22 may be, for example, about 350 mm to 600 mm. The beam formation (height) of the reinforcing beam portion 22 may be about 500 mm to 900 mm.

  The reinforcing intersection 23 is disposed on the outer wall surface of the existing building 10 and at a position corresponding to the intersection 13. The reinforcing intersection 23 connects the ends of the reinforcing column 21 and the reinforcing beam 22. Therefore, the reinforcing intersection 23 is located at the intersection between the reinforcing column 21 and the reinforcing beam 22. Therefore, the reinforcing structure 20 is configured in a lattice shape by the reinforcing column part 21, the reinforcing beam part 22, and the reinforcing intersection part 23. The thickness (depth) of the reinforcing intersection 23 may be, for example, about the same as the thickness of the reinforcing beam 22 or 600 mm or less.

  The reinforcing column portion 21 and the reinforcing beam portion 22 are made of, for example, reinforced concrete (a hardened concrete body in which the reinforcing bars are embedded). For example, as shown in FIG. 3, the reinforcing beam portion 22 is configured by embedding a reinforcing bar R2 in a hardened concrete body. The reinforcing bar R2 includes a plurality of main bars R2a extending in the extending direction of the reinforcing beam portion 22, and a plurality of shear reinforcing bars R2b attached to the plurality of main bars R2a so as to surround the plurality of main bars R2a.

The reinforcing intersection 23 is made of, for example, a mortar hardened body in which reinforcing bars are embedded. The cured mortar is formed by curing polymer cement mortar. In this embodiment, the compressive strength of a mortar hardened body is larger than the compressive strength of a hardened concrete body when compared with the age of the same day. The compressive strength at the age of 28 days of the cured mortar is preferably 65 N / mm ² or more.

<Polymer cement mortar>
Here, the polymer cement mortar will be described. Polymer cement mortar is a mixture of a polymer cement composition and water.

(I) Polymer cement composition The polymer cement composition is a polymer cement composition for a reinforcing method, and includes cement, fine aggregate, fluidizer, re-emulsifying powder resin, inorganic expansion material, and synthetic resin. Contains fiber.

  Cement is a common hydraulic material, and any commercially available product can be used. Among them, it is preferable to include Portland cement as defined in JIS R 5210: 2009 “Portland cement”.

From the viewpoint of strength development, the Blaine specific surface area of cement is
Preferably 2000cm ² / g~6000cm ² / g,
More preferably, it is 2500 cm < ² > / g-5000 cm < ² > / g.

  Examples of the fine aggregate include sand such as quartz sand, river sand, land sand, sea sand, and crushed sand. As the fine aggregate, one kind selected from these may be used alone, or two or more kinds may be used in combination. Among these, it is preferable to contain silica sand from the viewpoint of further smoothing the filling property of the polymer cement mortar into the mold.

  When a fine aggregate is screened by the method specified in JIS A 1102: 2014 “Aggregate Screening Test Method”, the mass fraction (%) remaining between successive screens is 0 at a sieve opening of 2000 μm. It is preferable that it is mass%. When all fine aggregates pass through a sieve having a sieve opening of 2000 μm, the mass fraction is 0% by mass.

The mass fraction (%) that remains between each successive sieve is
In 1180 micrometers of sieve openings, it is 5.0-25.0,
In a sieve opening of 600 μm, it is 20.0 to 50.0,
In a sieve opening of 300 μm, it is 20.0 to 50.0,
It is preferably 5.0 to 25.0 at a sieve opening of 150 μm.

The mass fraction (%) that remains between each successive sieve is
In a sieve opening of 1180 μm, it is 10.0 to 20.0,
In a sieve opening of 600 μm, it is 25.0 to 45.0,
In a sieve opening of 300 μm, it is 25.0 to 45.0,
In the case where the sieve opening is 150 μm, it is more preferably 10.0 to 20.0.

  When the fine aggregate is screened according to the above rules, the mortar having better material separation resistance and fluidity is obtained because the mass fraction (%) staying between each successive screen is within the above range. A mortar cured body having higher compressive strength can be obtained.

When the fine aggregate is screened by the method defined in JIS A 1102: 2014 “Aggregate Screening Test Method”, the coarse particle ratio of the fine aggregate is preferably 1.80 to 3.00,
More preferably, it is 2.00-2.80.

  When the coarse particle ratio of the fine aggregate is in the above range, a polymer cement mortar having better material separation resistance and fluidity and a mortar cured body having better strength characteristics can be obtained.

  The above sieving can be performed using several sieves having different openings as defined in JIS Z 8801-1: 2006 “Test sieve—Part 1: Metal mesh sieve”.

The content of fine aggregate is 100 parts by mass of cement,
Preferably it is 80-250 parts by mass,
More preferably, it is 90 to 200 parts by mass,
More preferably, it is 95 mass parts-150 mass parts.

  By setting the content of the fine aggregate to the above range, a mortar hardened body having higher compressive strength can be obtained.

  Examples of the fluidizing agent include formaldehyde condensates of melamine sulfonic acid, casein, calcium caseinate, and polycarboxylic acids. The fluidizing agent may be used alone or in combination of two or more selected from these. Among these, from the viewpoint of obtaining a high water reducing effect, it is preferable to include a polycarboxylic acid-based fluidizing agent. By using a polycarboxylic acid-based fluidizing agent, the water powder ratio can be reduced, and the strength development of the mortar cured body can be further improved.

The content of the fluidizing agent is 100 parts by mass of cement,
Preferably it is 0.05 mass part-2.0 mass parts,
More preferably, it is 0.10 mass part-1.0 mass part.

  By setting the content of the fluidizing agent in the above range, a polymer cement mortar having better fluidity can be obtained. Moreover, the mortar hardening body which has much higher compressive strength can be obtained.

  The type and production method of the re-emulsified powder resin are not particularly limited, and those produced by a known production method may be used. The re-emulsified powder resin may have an anti-blocking agent on the surface. From the viewpoint of durability of the cured mortar, the re-emulsified powder resin preferably contains acrylic. Furthermore, from the viewpoint of adhesiveness and compressive strength, the glass transition temperature (Tg) of the re-emulsified powder resin is preferably in the range of −5 ° C. to 20 ° C.

The content of the re-emulsified powder resin is 100 parts by mass of cement,
Preferably, it is 0.2 part by mass to 5.0 parts by mass,
More preferably, it is 0.5 mass part-4.0 mass parts.

  By setting the content of the re-emulsifying powder resin in the above range, the adhesiveness of the polymer cement mortar and the compressive strength of the mortar hardened body can be achieved at a higher level.

  Examples of the inorganic expansion material include quick lime-gypsum expansion material, gypsum expansion material, calcium sulfoaluminate expansion material, and quick lime-gypsum-calcium sulfoaluminate expansion material. As the inorganic expansion material, one kind selected from these may be used alone, or two or more kinds may be used in combination. Among these, it is preferable to include a quicklime-gypsum-calcium sulfoaluminate-based expansion material from the viewpoint of further improving the compressive strength of the mortar cured body.

The content of the inorganic expansion material is 100 parts by mass of cement,
Preferably it is 2.0 parts by mass to 10.0 parts by mass,
More preferably, it is 3.0 mass parts-9.0 mass parts.

  By setting the content of the inorganic expansive material in the above range, more appropriate expansibility can be exhibited and shrinkage of the mortar hardened body can be suppressed.

  Examples of the synthetic resin fiber include polyethylene, ethylene / vinyl acetate copolymer (EVA), polyolefin such as polypropylene, polyester, polyamide, polyvinyl alcohol, vinylon, and polyvinyl chloride. The synthetic resin fibers may be used alone or in combination of two or more selected from these.

The fiber length of the synthetic resin fiber is from the viewpoint of dispersibility in mortar and crack resistance improvement of the mortar cured body.
Preferably it is 4-20mm,
More preferably, it is 6 mm to 18 mm.

The content of the synthetic resin fiber is 100 parts by mass of cement,
Preferably, it is 0.10 parts by mass to 0.60 parts by mass,
More preferably, it is 0.15 mass part-0.55 mass part.

  By setting the fiber length and content of the synthetic resin fiber in the above range, the dispersibility in the mortar and the crack resistance of the mortar cured body can be further improved.

  The polymer cement composition may contain a setting modifier, a thickener, a metal expansion material, an antifoaming agent, and the like depending on the application.

(Ii) Polymer cement mortar The polymer cement mortar includes the polymer cement composition described above and water. The polymer cement mortar can be prepared by blending and kneading the above polymer cement composition and water. The polymer cement mortar thus prepared has excellent fluidity (flow value). For this reason, the filling into the mold for forming the reinforcing structure 20 can be performed smoothly. Therefore, it can be suitably used as a polymer cement mortar for the reinforcing structure 20. When preparing the polymer cement mortar, the flow value of the polymer cement mortar can be adjusted by appropriately changing the water powder ratio (water amount / polymer cement composition amount).

The water powder ratio is
Preferably, it is 0.13-0.18,
More preferably, it is 0.14-0.17.

  The flow value in this specification is measured by the following procedure. A cylindrical vinyl chloride pipe having an inner diameter of 50 mm and a height of 100 mm is placed on a glass sheet having a thickness of 5 mm. At this time, it arrange | positions so that one end of a pipe made from a vinyl chloride may contact polishing glass, and the other end may face upward. The polymer cement mortar is poured from the opening on the other end side, and the vinyl chloride pipe is filled with the polymer cement mortar, and then the vinyl chloride pipe is pulled up vertically. After the mortar spread stops, the diameter (mm) in two directions perpendicular to each other is measured. Let the average value of a measured value be a flow value (mm).

The flow value of polymer cement mortar is
Preferably, it is 170 mm to 250 mm,
More preferably, it is 190 mm to 245 mm,
More preferably, it is 210 mm-240 mm.

  When the flow value is in the above range, a polymer cement mortar excellent in material separation resistance and filling property can be obtained.

(Iii) Mortar cured body The mortar cured body can be formed by curing polymer cement mortar. The mortar hardened body formed in this way has high compressive strength when integrated with the reinforced concrete reinforcing column portion 21 and the reinforcing beam portion 22 constituting the reinforcing structure 20, and thus the earthquake resistance of the existing building 10. Can be improved.

As used herein, “compressive strength” refers to a cylindrical specimen having a diameter of 5 cm and a height of 10 cm in accordance with JIS A 1132: 2014 “How to make a specimen for concrete strength test”, and JIS A 1108: 2006 “Concrete”. Means a value (N / mm ² ) measured according to “compressive strength test method”.

The compressive strength of the cured mortar body as measured by the above test method is 28 days old.
Preferably, it is 60 N / mm ² or more,
More preferably, it is 65 N / mm ² or more,
More preferably, it is 70 N / mm ² or more.

  When the compressive strength is in the above-described range, when integrating with the reinforced concrete reinforcing column portion 21 and the reinforcing beam portion 22 constituting the reinforcing structure 20, it is possible to exhibit further excellent seismic performance.

<Description of notch>
Next, the relationship between the beam portion 12 and the reinforcing beam portion 22 will be described in detail with reference to FIGS. 2 and 3. In the present embodiment, the beam portion 12 in which the reinforcing beam portion 22 is disposed is provided with two notches 12A between adjacent column portions 11 as shown in FIG. One notch portion 12 </ b> A is located near one end of the beam portion 12 between adjacent column portions 11. The other notch portion 12 </ b> A is located near the other end of the beam portion 12 between the adjacent column portions 11. The notch 12A is separated from the intersection 13 adjacent to the notch 12A.

  As shown in FIG. 3, the notch portion 12 </ b> A is provided on the upper edge side of the beam portion 12 and on the outer surface side of the existing building 10. The cutout portion 12 </ b> A is recessed stepwise toward the inside of the existing building 10. In the present embodiment, the notch 12A has a rectangular parallelepiped shape. Therefore, each surface constituting the notch 12A is substantially orthogonal to other adjacent surfaces.

  The width (length in the horizontal direction) w (see FIG. 2) of the notch 12A is about 1/50 to 1/4 of the length of the beam 12 (inner method of the adjacent pillars 11) W. Also good. When the width w is 1/50 or more of the length W, a portion of the hardened concrete body of the reinforcing beam portion 22 located at the notch 12A tends to be firmly locked by the notch 12A. If the width w is ¼ or less of the length W, the notch portion 12A is positioned closer to the end rather than the central portion of the beam portion 12, so that the long-term load on the central portion of the beam portion 12 is reduced. There is a tendency. For example, the lower limit of the width w may be about 80 mm or about 100 mm.

  The horizontal distance 11 (see the same figure) in the horizontal direction between the notch 12A and the intersection 13 adjacent to the notch 12A may be larger than the beam formation H (see FIG. 3) of the beam 12. Good. In general, when a horizontal external force acts on the reinforced building 1 due to an earthquake or the like, a bending force is generated at the end of the beam portion 12. Thereby, a crack extending obliquely at an angle of about 30 ° to 45 ° from the corner of the boundary portion between the end portion of the beam portion 12 and the intersecting portion 13 may occur at the end portion of the beam portion 12. When this crack reaches the notch portion 12A, the strength of the beam portion 12 tends to decrease. However, if the linear distance l1 is larger than the beam H, even if a crack occurs at an angle of about 45 °, the crack is difficult to reach the notch 12A. Therefore, it is possible to sufficiently secure the supporting force of the reinforcing beam portion 22 by the beam portion 12. The lower limit of the straight line distance l1 may be, for example, about ¼ of the beam formation H or about １ ／ of the beam formation H. The lower limit of the linear distance l1 may be about 100 mm, for example.

  In the horizontal direction, the linear distance l2 (see FIG. 2) between the intersection 13 adjacent to the notch 12A and the inner edge of the notch 12A (the edge near the center of the beam 12) is the beam It may be 1/3 or less of 12 lengths (inner method) W.

  The lower limit of the height h (see FIG. 3) in the vertical direction of the notch 12A may be, for example, about 50 mm or about 100 mm. The upper limit of the height h may be, for example, about ½ of the beam formation H of the beam portion 12.

  For example, the lower limit of the depth d (see the same figure) in the horizontal direction of the notch 12A may be about 20 mm. The upper limit of the depth d may be, for example, about ¼ of the depth D of the beam portion 12 (see the figure).

  As shown in FIG. 3, a hardened concrete body of the reinforcing beam portion 22 is disposed in the notch portion 12A. That is, the concrete hardened body of the reinforcing beam portion 22 is locked to the notch portion 12A. Therefore, the reinforcing beam portion 22 is supported by the beam portion 12.

  As shown in FIG. 3, the connecting member 30 connects the beam portion 12 and the reinforcing beam portion 22. The connecting member 30 is inserted through both the beam portion 12 and the reinforcing beam portion 22 so as to extend in the horizontal direction. That is, the proximal end portion of the connection member 30 is embedded in the beam portion 12, and the distal end portion of the connection member 30 is embedded in the reinforcing beam portion 22. For example, the connecting member 30 may be a reinforcing bar or an anchor bolt.

  In FIG. 3, two connecting members 30 are arranged in the vertical direction. The connection member 30 located on the upper side passes through the notch 12A. The connection member 30 located on the lower side passes below the notch 12A. The number and position of the connection members 30 are not particularly limited.

<Manufacturing method of reinforced building>
Then, the method (manufacturing method of the reinforced building 1) which constructs the reinforcement structure 20 with respect to the intermediate | middle layer part of the existing building 10 is demonstrated. First, a predetermined portion of the beam portion 12 located in the intermediate layer portion is wound with a concrete hammer or the like to form a notch portion 12A. At this time, it may be rolled to such an extent that the reinforcing bar R1 of the beam portion 12 is exposed.

  Next, an insertion hole is formed in the region corresponding to the notch 12A in the beam portion 12 and the region below the notch 12A in the beam portion 12 using a drill or the like. Next, the connection member 30 is inserted into the insertion hole, and the proximal end portion of the connection member 30 is embedded in the beam portion 12. Thereby, the connection member 30 is fixed to the beam portion 12. Note that the distal end portion of the connection member 30 is located outside the insertion hole.

  Next, reinforcing bars are arranged on the outer wall surface of the existing building 10 and at positions corresponding to the column part 11, the beam part 12 and the intersection part 13. Next, a beam part formwork is configured so as to cover the reinforcing bar R2 arranged in the beam part 12. Thereby, the reinforcing bar R2 and the tip of the connecting member 30 are surrounded by the beam part formwork and the outer wall surface of the beam part 12. Next, concrete is placed in the beam form. At this time, the concrete is also filled into the notch 12A. After the concrete is hardened to become a hardened concrete body, the reinforcing beam 22 is formed at a position corresponding to the beam 12 by removing the beam form.

Next, the crossing formwork is configured so as to cover the reinforcing bars arranged in the crossing part 13 at both ends of the reinforcing beam part 22 formed in the previous step. As a result, the reinforcing bars are surrounded by the cross section formwork and the outer wall surface of the cross section 13. Next, the polymer cement mortar is filled in the mold for intersection. The filling of the polymer cement mortar into the cross form for the crossing is performed after the penetration resistance value of the concrete placed in the form for the beam part becomes 0.1 N / mm ² or more (for example, about 2 hours elapses). After). After the polymer cement mortar is hardened to form a mortar hardened body, the crossing part form is removed, so that the reinforcing crossing portions 23 are formed at positions corresponding to the crossing portion 13 and at both ends of the reinforcing beam portion 22. . Here, the “penetration resistance value” is a value obtained by the test method described in JIS A 1147-2007 “Concrete setting time test method”.

  Next, on the upper side of the reinforcing intersection 23 formed in the previous step, the column part form is configured so as to cover the reinforcing bars arranged in the column part 11. Thus, the reinforcing bars are surrounded by the column part formwork and the outer wall surface of the column part 11. Next, concrete is placed in the column form. By removing the column part formwork after the concrete has hardened to become a concrete hardened body, the reinforcing column part 21 is formed at a position corresponding to the column part 11 and above the reinforcing intersection part 23. In other words, the reinforcing intersection 23 formed in the previous step is located at the lower end of the reinforcing pillar 21.

  Next, on the upper end side of the reinforcing column portion 21 formed in the previous step, the beam portion formwork is configured so as to cover the reinforcing bars arranged in the beam portion 12. As a result, the reinforcing bar is surrounded by the beam part formwork and the outer wall surface of the beam part 12. Next, concrete is placed in the beam form. After the concrete has hardened to become a hardened concrete body, the beam form is removed, so that the reinforcing beam part is positioned at the upper end side of the reinforcing column part 21 formed in the previous step and corresponding to the beam part 12. 22 is formed. In other words, the reinforcing beam portion 22 formed in the current step is positioned above the reinforcing beam portion 22 formed in the previous step.

  Thereafter, similarly to the above, the reinforcing intersection 23, the reinforcing pillar portion 21, and the reinforcing beam portion 22 are sequentially formed from the lower side to the upper side of the existing building 10. As described above, the reinforced structure 20 is provided in the existing building 10 and the reinforced building 1 is completed.

<Action>
In the present embodiment as described above, the reinforcing beam portion 22 is supported by the beam portion 12 by being locked to the notch portion 12A. Therefore, the notch portion 12A of the beam portion 12 functions like a hook for hooking the reinforcing beam portion 22 to the existing building 10, so that the reinforcing beam portion 22 is supported to the existing building 10 and the notch portion. A large shear resistance is exhibited at 12A. Therefore, since the weight of the reinforcing beam portion 22 is transmitted to the beam portion 12 through the notch portion 12A very reliably, the reinforcing beam portion 22 can be reinforced without constructing the lower portion of the existing building 10. It is possible to reinforce the required intermediate layer portion of the existing building 10. As a result, it is possible to easily and inexpensively reinforce the intermediate layer portion of the existing building 10.

  In the present embodiment, the notch 12A is located at the end of the beam 12 and is separated from the column 11 adjacent to the notch 12A. Here, when an external force in the horizontal direction acts on the reinforced building 1 due to the occurrence of an earthquake or the like, the existing building 10 is likely to be broken at the connection portion between the beam portion 12 and the intersection portion 13. For this reason, if the notch 12A is separated from the column 11 adjacent to the notch 12A, it is difficult to cause a reduction in the cross-sectional area in the portion of the beam 12 where breakage is likely to occur. Therefore, sufficient strength of the beam portion 12 can be ensured.

  By the way, since the beam part 12 of the existing building 10 supports the weight of floors, walls and the like for a long time, the central part of the beam part 12 is particularly easily bent. Therefore, if the notch 12A is provided at the center of the beam 12, the beam 12 may be greatly bent. However, in this embodiment, the linear distance l2 can be set to 1/3 or less of the length W of the beam portion 12. In this case, the inner edge of the notch 12 </ b> A is located away from the center of the beam 12. Therefore, the portion where the reinforcing beam portion 22 is supported by the beam portion 12 is not easily bent. Accordingly, it is possible to sufficiently secure the supporting force of the reinforcing beam portion 22 by the beam portion 12.

  In the present embodiment, the height h may be 50 mm or more and 1/2 of the beam formation H of the beam portion 12. When the height h is 50 mm or more, the portion of the hardened concrete body of the reinforcing beam portion 22 located at the notch 12A tends to be firmly locked by the notch 12A. If the height h is ½ or less of the beam formation H of the beam portion 12, the size of the portion located below the notch portion 12A in the beam portion 12 is sufficiently secured. Some reinforcing beam portions 22 tend to be firmly supported by the beam portions 12.

  In the present embodiment, the connecting member 30 is inserted through both the beam portion 12 and the reinforcing beam portion 22 into both of them. Therefore, the beam portion 12 and the reinforcing beam portion 22 are integrated via the connection member 30. Accordingly, since the weight of the reinforcing structure 20 is transmitted to the beam portion 12 via the connection member 30, the reinforcing beam portion 22 can be more reliably supported with respect to the existing building 10.

<Other embodiments>
As mentioned above, although embodiment concerning this indication was described in detail, you may add various deformation | transformation to said embodiment within the range of the summary of this invention. For example, one or more notch portions 12 </ b> A may be provided in the beam portion 12 between the adjacent intersection portions 13.

  The cutout portion 12A may not be separated from the intersecting portion 13 adjacent to the cutout portion 12A.

  The proximal end portion of the connecting member 30 may be connected to the reinforcing bar R1 of the beam portion 12. As a method of connecting the base end portion of the connecting member 30 to the reinforcing bar R1 of the beam portion 12, for example, a method of hooking the base end portion bent in a hook shape to the reinforcing bar R1, or welding the base end portion to the reinforcing bar R1. And a method of passing the connecting member 30 through the beam portion 12 so that the base end portion is exposed in the existing building 10 and fastening a nut to the base end portion from the inside of the existing building 10. . When the beam portion 12 is made of steel reinforced concrete, a method of screwing the base end portion to the steel frame, a method of welding the base end portion to the steel frame, or the like can be given. On the other hand, the reinforcing structure 20 may not have the connection member 30.

  As FIG. 4 shows, the corner | angular part of 12 A of notches may be depressed toward the downward direction. In this case, a portion of the hardened concrete body of the reinforcing beam portion 22 located at the notch portion 12A is likely to bite into the notch portion 12A. Therefore, the reinforcing beam portion 22 can be more reliably supported with respect to the existing building 10. Here, as shown in FIG. 4, an angle θ formed by a main surface extending in the beam forming direction of the beam portion 12 and a bottom surface extending in the depth direction of the beam portion 12 among the surfaces constituting the notch portion 12A. May be about 45 ° to 90 °.

  As shown in FIG. 5, the reinforcing structure 20 may include a metal plate 32 positioned between the notch portion 12 </ b> A and the reinforcing beam portion 22. The metal plate 32 should just be located in the surface of the notch part 12A at least. In FIG. 5, the metal plate 32 extends along the outer surface of the beam portion 12 from the notch portion 12 </ b> A to the lower portion thereof, and has a crank shape. Since the metal plate 32 is interposed between the notch portion 12A and the reinforcing beam portion 22, the notch portion 12A is reinforced by the metal plate 32, so that a greater shear resistance can be obtained at the notch portion 12A. it can.

  The metal plate 32 is attached to the notch 12A before the reinforcing bar R2 is disposed on the outer surface of the beam 12. Therefore, when concrete is placed in the beam form, the metal plate 32 is also covered with the beam form. Before attaching the metal plate 32 to the notch 12A, a filler (eg, putty, mortar, etc.) may be supplied to the surface of the notch 12A to make the surface of the notch 12A substantially flat. When the reinforcing bar R1 is exposed from the notch 12A, the exposed reinforcing bar R1 and the metal plate 32 may be connected by welding, bonding, or the like.

  As shown in FIG. 5, the metal plate 32 may be formed with a through hole 32 a extending in the thickness direction. The through hole 32 a is formed at a location corresponding to the installation position of the connection member 30 with respect to the beam portion 12. Therefore, the connection member 30 can be inserted into the through hole 32a. The connection member 30 is fixed to the metal plate 32 with a nut. In this case, the beam portion 12, the reinforcing beam portion 22, and the metal plate 32 are integrated via the connection member 30. Therefore, the weight of the reinforcing structure 20 is transmitted to the beam portion 12 via the connection member 30 and the metal plate 32. Accordingly, the reinforcing beam portion 22 can be more reliably supported with respect to the existing building 10. In addition, after attaching the metal plate 32 to the notch portion 12A, the connecting member 30 may be provided in the beam portion 12 through the through hole 32a, or in the through hole 32a after the connecting member 30 is provided in the beam portion 12. You may attach the metal plate 32 to the notch part 12A so that these connection members 30 may penetrate.

  As shown in FIG. 5, the metal plate 32 may be provided with a fixing member 34 extending in the reinforcing beam portion 22. Examples of the fixing member 34 include a stud bolt and a reinforcing bar. The fixing member 34 may be connected to the metal plate 32 by welding or the like. In this case, the concrete hardened body of the reinforcing beam portion 22 and the metal plate 32 are integrated via the fixing member 34. Therefore, the weight of the reinforcing structure 20 is transmitted to the beam portion 12 through the fixing member 34 and the metal plate 32. Accordingly, the reinforcing beam portion 22 can be more reliably supported with respect to the existing building 10. When concrete is placed in the beam part formwork, the metal plate 32 and the fixing member 34 are also covered with the beam part formwork.

  As shown in FIG. 6, not only the hardened concrete body of the reinforcing beam portion 22 but also a hardened mortar body of the reinforcing intersection 23 may be disposed in the notch 12A. That is, the concrete hardened body of the reinforcing beam portion 22 and the mortar hardened body of the reinforcing crossing portion 23 may be locked to the same notch 12A. In this case, the reinforcing beam portion 22 and the reinforcing intersection portion 23 are supported by the beam portion 12.

  As shown in FIG. 7, a plurality of notches 12 </ b> A may be provided at the end of the beam portion 12. Also in this case, the linear distance between the inner edge of the innermost notch 12A among the plurality of notches 12A and the intersection 13 adjacent to the notches 12A is the It may be 1/3 or less of the length (inner method) W.

  DESCRIPTION OF SYMBOLS 1 ... Reinforced building, 10 ... Existing building, 20 ... Reinforcement structure, 11 ... Column part, 12 ... Beam part, 12A ... Notch part, 13 ... Intersection part, 21 ... Reinforcement pillar part, 22 ... Reinforcement beam part, DESCRIPTION OF SYMBOLS 23 ... Reinforcement crossing part, 30 ... Connection member, 32 ... Metal plate, 32a ... Through-hole, 34 ... Fixing member, R1, R2 ... Reinforcing bar.

Claims (20)

An existing building,
A reinforcing structure for reinforcing the existing building,
The existing building is
A column containing a reinforcing bar inside,
A beam part including a reinforcing bar inside,
The column part and the beam part are located at the intersections and have an intersection part connected to the end part of the pillar part and the end part of the beam part, respectively.
The reinforcing structure is
Reinforcing pillars that are disposed along the pillars and include a hardened concrete body in which reinforcing bars are embedded;
Reinforced beam portion including a hardened concrete body arranged along the beam portion and embedded with reinforcing bars,
A reinforcing intersection including a polymer cement mortar hardened body which is disposed at a position corresponding to the intersection and is connected to an end of the reinforcing pillar and an end of the reinforcing beam, respectively, and a reinforcing bar is embedded therein. ,
A notch is provided in a corner on the upper edge side of the beam portion and on the outer surface side of the existing building,
The reinforced beam part is a reinforced building supported by the beam part by locking the hardened concrete body to the notch part.   The reinforced building according to claim 1, wherein the notch is located at an end of the beam portion and is separated from the intersecting portion adjacent to the notch.   The inner edge of the notch part is 1/3 of the inner method of the column part located on both ends of the beam part where the notch part is provided from the intersecting part adjacent to the notch part. The reinforced building according to claim 2, wherein the reinforced building is located within a range of up to.   The reinforced building according to any one of claims 1 to 3, wherein a length of the cutout portion in a horizontal direction is 1/50 to 1/4 of a length of the beam portion.   The reinforced building according to any one of claims 1 to 4, wherein a height of the notch portion in a vertical direction is 50 mm or more and 1/2 or less of a beam formation of the beam portion.   The reinforced building according to any one of claims 1 to 5, wherein a corner portion of the cutout portion is recessed downward.   The reinforced building according to any one of claims 1 to 6, wherein the reinforcing structure further includes a connection member inserted into both the beam portion and the reinforcing beam portion.   The reinforced structure according to any one of claims 1 to 6, wherein the reinforcing structure further includes a metal plate positioned between the notch portion and the reinforcing beam portion. The reinforcing structure further includes a connecting member inserted into both of the beam portion and the reinforcing beam portion, both inside,
The reinforced building according to claim 8, wherein the connection member is inserted through a through hole provided in the metal plate.   The reinforced building according to claim 8 or 9, wherein the metal plate is provided with a fixing member extending in the reinforcing beam portion. A column part, a beam part including a reinforcing bar inside, and an intersection part located at a position where the column part and the beam part intersect and connected to an end part of the pillar part and an end part of the beam part, respectively. A method of manufacturing a reinforced building in which a reinforced structure is provided in an existing building and the existing building is reinforced by the reinforced structure,
A first step of forming a notch by rolling a corner on the upper edge side of the beam portion and on the outer surface side of the existing building;
After the first step, a second step of arranging reinforcing bars at positions corresponding to the column part, the beam part, and the intersection part,
After the second step, a first mold is provided so as to cover the reinforcing bars arranged in the pillar, and a reinforcing pillar is formed by placing concrete in the first mold. A third step;
After the second step, a second formwork is provided so as to cover the reinforcing bars arranged in the beam part, and concrete is placed in the second formwork while filling the notch part. A fourth step of forming the reinforcing beam portion by,
After the second step, a third mold is provided so as to cover the reinforcing bars arranged at the intersection, and a reinforcing cement intersection is formed by filling the third mold with polymer cement mortar. The manufacturing method of the reinforced building including the 5th process to do.   The method according to claim 11, wherein the notch is located at an end of the beam portion and is separated from the intersection adjacent to the notch.   The inner edge of the notch part is 1/3 of the inner method of the column part located on both ends of the beam part where the notch part is provided from the intersecting part adjacent to the notch part. The method according to claim 12, which is located within a range of up to.   The method according to any one of claims 11 to 13, wherein a length of the cutout portion in a horizontal direction is 1/50 to 1/4 of a length of the beam portion.   The method according to any one of claims 11 to 14, wherein a height of the notch portion in a vertical direction is not less than 50 mm and not more than ½ of a beam formation of the beam portion.   The method according to any one of claims 11 to 15, wherein a corner portion of the notch portion is recessed downward. After the first step and before the fourth step, the method further includes a sixth step of attaching the proximal end portion of the connecting member in the beam portion such that the distal end portion is located outside,
In the fourth step, a second mold is provided so as to cover the reinforcing bars arranged in the beam and the tip of the connecting member, and the inside of the second mold is filled with the notch. The method according to any one of claims 11 to 16, wherein the reinforcing beam portion is formed by placing concrete on the surface. A sixth step of attaching a metal plate to the notch after the first step and before the fourth step;
In the fourth step, a second mold is provided so as to cover the reinforcing bars and the metal plate arranged in the beam portion, and concrete is placed in the second mold while filling the notch. The method according to any one of claims 11 to 16, wherein the reinforcing beam portion is formed by driving. After the first step and before the fourth step, the method further includes a seventh step of attaching the proximal end portion of the connecting member in the beam portion so that the distal end portion is located outside,
In the fourth step, in a state where the connection member is inserted into a through-hole provided in the metal plate, the reinforcing bar disposed in the beam portion, the distal end portion of the connection member, and the metal plate are covered. 19. The method according to claim 18, further comprising: forming a reinforcing beam portion by providing a second formwork and placing concrete in the second formwork while filling the notch portion. The metal plate is provided with a fixing member,
In the fourth step, the second formwork covers the fixing member,
The method according to claim 18 or 19, wherein the fixing member extends into the reinforcing beam portion.

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