JP2019190079A - Earthquake-proof reinforcement construction method - Google Patents

Abstract

To provide an earthquake-proof reinforcement construction method which can construct an earthquake-proof reinforcement wall in a short construction period.SOLUTION: An earthquake-proof reinforcement construction method includes: an anchor mounting step of mounting a plurality of anchor members 11 on a frame 3 of a building; a bar arranging step of disposing a plurality of reinforcements 12 vertically and horizontally in the frame 3; a form installing step of installing a form in the frame 3; an installing step of filling, in the form, a high strength grout material constituted by an aggregate containing cement, expansive admixture and pea gravel, a grout composition containing a cement dispersant, a thickner and a foaming agent, and water within a range which does not exceed a beam width in a beam width direction of a beam 2 so that a thickness of an earthquake-proof wall 10 becomes equal to or less than 130 mm; a curing step of curing the high strength grout material; and a form dismantling step of dismantling the form. The form installing step, the installing step and the curing step are performed only once respectively.SELECTED DRAWING: Figure 1

Description

    The present invention relates to a seismic reinforcement method.

    Conventionally, seismic reinforcement has been performed on existing reinforced concrete structures by various methods. For example, in Patent Document 1 below, seismic reinforcement that improves the seismic strength of an existing building by constructing a new reinforced concrete seismic reinforcement wall in a frame surrounded by pillars and beams of the existing building. The construction method is disclosed.

JP 2016-142022 A

    However, in the conventional method of constructing a new reinforced concrete seismic reinforcement wall, the concrete sinks, so after the concrete is placed, there is no contraction in the gap formed between the existing beam and the top of the newly installed concrete wall. It was necessary to place mortar. As described above, the conventional construction method has a problem that it is necessary to perform the placing process twice and the construction period is long.

    If the beam width of the existing beam is narrow, the distance between the end face on the reinforcement side of the existing wall (the side where the seismic reinforcement wall is built in the horizontal direction perpendicular to the existing wall) and the end face on the reinforcement side of the existing beam is Because it is short, the seismic reinforcement wall with the thick wall of the conventional construction method protrudes from the upper and lower existing beams to the reinforcement side. Therefore, in such a case, it is necessary to increase the number of beams so that the seismic reinforcement walls do not protrude from the upper and lower beams. In this case, for the upper beam, the non-shrink mortar wall may be extended upward so that the non-shrink mortar beam is formed on the side of the existing beam. For the beam), the side of the beam must be separated from the seismic reinforcement wall, and a formwork must be installed, and the non-shrink mortar beam must be increased by filling it with non-shrink mortar. In addition, since various wiring, piping, ducts, etc. are arranged on the back of the ceiling, before adding non-shrink mortar beams to the side of the lower beam, these wiring, piping, ducts, etc. May need to be relocated. As described above, in the conventional construction method, since the seismic reinforcement wall becomes thick, it is often necessary to increase the number of beams, and it is necessary to perform various operations in addition to the construction of the earthquake resistance reinforcement wall, resulting in a longer construction period. There was a fear.

    This invention is made | formed in view of this point, The objective is to provide the earthquake-resistant reinforcement construction method of constructing | assembling the earthquake-resistant reinforcement wall which can be constructed | assembled in a construction period shorter than before.

    The present invention provides a seismic reinforcement method for increasing the holding strength of the building by constructing a seismic reinforcing wall in a frame surrounded by a pair of left and right columns and a pair of upper and lower beams of the building. An anchor attaching step for attaching a plurality of anchor members so as to protrude into the frame, a bar arrangement step for arranging a plurality of reinforcing bars vertically and horizontally in the frame, and the earthquake-proof reinforcing wall in the frame. A mold installation step for installing a mold for the above, a grout composition containing cement, an expanding material, an aggregate containing bean gravel, a cement dispersant, a thickener, and a foaming agent, and water in the mold A placing step of filling a high-strength grout material composed of the above-mentioned anti-seismic reinforcing wall into a range not exceeding the beam width in the beam width direction so that the thickness of the seismic reinforcement wall is 130 mm or less; The high strength filled in the mold at A curing step for curing the grout material to form the wall body including the plurality of reinforcing bars; and a mold disassembly step for disassembling the mold after the curing step. Each of the setting process and the curing process is performed only once.

    According to the present invention, the wall of the seismic reinforcement wall is not made of concrete like the conventional reinforced concrete seismic reinforcement wall, but is made of cement, an expanded material, an aggregate containing bean gravel, a cement dispersant, an increase It was decided to comprise the hardened | cured material of the high intensity | strength grout material comprised with the grout composition containing water and a foaming agent, and water. Since the high-strength grout material contains an expansion material and a foaming agent, the high-strength grout material hardly sinks when cured, and has the same non-shrinkage property as a non-shrink mortar. On the other hand, since the high-strength grout material contains bean gravel, the temperature rise due to drying shrinkage and heat of hydration of the cured product is significantly smaller than that of a general non-shrink mortar. According to such a seismic reinforcement method, unlike the conventional reinforced concrete seismic reinforcement wall, it is not necessary to place non-shrink mortar after placing concrete. Since the wall body can be configured, it is possible to shorten the construction period for constructing the earthquake-proof reinforcement wall.

    In addition, since the gravel material used is bean gravel, the aggregate particles are rounded, and even when the maximum size of the aggregate is as small as 7 mm or less, the slump flow is 500 mm or more. High fluidity can be secured. From this, the thickness of the seismic reinforcement wall can be reduced to 130 mm or less. Therefore, even if the beam width of the existing beam is narrow and the distance between the end face on the reinforcement side of the existing wall and the end face on the reinforcement side of the existing beam is short, the seismic reinforcement wall does not protrude from the existing beam in the beam width direction. It can be constructed, and the extra striking of the beam with non-shrink mortar can be omitted. Therefore, it is not necessary to move various wirings, pipes, ducts and the like on the back of the ceiling, and the construction period for constructing the earthquake-resistant reinforcing wall 10 can be greatly shortened from this point.

    As described above, according to the present invention, it is possible to provide an earthquake resistant reinforcement method capable of constructing an earthquake resistant reinforcement wall in a shorter construction period than before.

FIG. 1 is a cross-sectional view showing a frame portion of a building in which a seismic reinforcing wall according to Embodiment 1 of the present invention is constructed. FIG. 2 is a cross-sectional view showing a frame portion of a building in which the seismic reinforcement wall according to Embodiment 1 of the present invention is constructed. FIG. 3 is a cross-sectional view showing a frame portion of a building in which a seismic reinforcement wall is constructed by a conventional method. FIG. 4 is a process chart showing the steps of each method in chronological order in order to compare the steps of the conventional method and the seismic reinforcement method (main method) according to the present invention.

    Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are merely preferred examples in nature, and are not intended to limit the scope of the present invention, its application, or its use.

Embodiment 1
As shown in FIG.1 and FIG.2, the earthquake-proof reinforcement wall 10 is constructed | assembled in the frame 3 comprised with the left-right pair 1 and the upper-lower paired beam 2 of the existing building of a reinforced concrete structure. In the first embodiment, an existing wall 4 made of reinforced concrete is built in the frame 3, and the seismic reinforcement wall 10 is added along the existing wall 4 to reinforce the existing wall 4. It is.

    The seismic reinforcing wall 10 includes a plurality of anchor members 11, a plurality of reinforcing bars 12, a split reinforcing bar 13, and a wall body 14.

    The anchor member 11 is for integrating the existing wall 4 to be seismically reinforced and the wall body 14 of the newly installed seismic reinforced wall 10. The anchor member 11 is attached to the frame 3 so as to protrude into the frame 3. Specifically, with respect to the pair of columns 1 and the pair of beams 2, a plurality of anchor members 11 are respectively embedded in the column 1 or the beam 2 at the tip side of the anchor bars, and the remaining portions are in the frame 3. It is attached to protrude. The remaining part of each anchor member 11 not embedded in the column 1 or the beam 2 is included in the wall body 14. For each column 1 and beam 2, a plurality of anchor members 11 are provided at predetermined intervals.

    The plurality of reinforcing bars 12 includes a plurality of vertical bars 12a extending in the vertical direction and a plurality of horizontal bars 12b extending in the horizontal direction. The plurality of vertical bars 12 a and the plurality of horizontal bars 12 b are arranged in a lattice shape in the frame 3 and are included in the wall body 14. The plurality of vertical bars 12a are arranged at predetermined intervals in the horizontal direction from the left end to the right end in the frame 3. The plurality of horizontal bars 12b are arranged at predetermined intervals in the vertical direction from the upper end to the lower end in the frame 3.

    The split reinforcing bar 13 is constituted by a spiral bar. The split reinforcing bars 13 are installed at the joint portion with the frame 3, that is, at the outer edge of the seismic reinforcing wall 10. The split reinforcing bars 13 are provided so as to face the pair of columns 1 and the pair of beams 2, and are included in the wall body 14.

    The wall body 14 is made of a hardened material of high-strength grout material, and is formed in the frame 3 so as to include a portion of the anchor member 11 in the frame 3, the reinforcing bar 12, and the split reinforcing bar 13. The wall body 14 is formed to have a thickness of 130 mm or less. Specifically, in this embodiment, the wall body 14 is formed with a thickness of 125 mm. The high-strength grout material constituting the wall body 14 is constructed by adding water and kneading to a premix grout composition in which cement, an expanding material, an aggregate, a cement dispersant, a thickener and a foaming agent are premixed. Manufactured on site. In the present embodiment, a high-strength grout material produced by kneading with 8 parts by mass or more and 20 parts by mass or less of water with respect to 100 parts by mass of the premix grout composition is used.

    The cement contained in the premix grout composition may be any hydraulic cement. The cement content in the premix grout composition is preferably 20% by mass or more and 35% by mass or less. If it is less than 20% by mass, strength development is inferior (compressive strength is small), and if it exceeds 35% by mass, drying shrinkage increases or temperature rise due to heat of hydration increases.

    The expansion material contained in the premix grout composition may be any material as long as the main component is a substance that grows hydrate crystals such as calcium hydroxide and ettringite by hydration and increases the bulk volume. However, a material suitable for JISA6202 “expanding material for concrete” is particularly preferable because the expansion rate relative to the amount of mixing is stable. The content of the expansion material in the premix grout composition is preferably 1% by mass or more and 7% by mass or less. If the amount is less than 1% by mass, it is difficult to obtain the effect of the expanding material, and the shrinkage increases. If the amount exceeds 7% by mass, the unconstrained portion may be reduced in strength.

    The thickener contained in the premix grout composition is not particularly limited, and at least one of water-soluble cellulose, polysaccharide, polyvinyl compound, alkyl starch, starch ether and the like can be used. Moreover, since a thickener is easy to premix, the thing of a powder (powder thickener) is preferable. The content of the thickener in the premix grout composition is preferably 0.0002% by mass or more and 0.02% by mass or less. If it is less than 0.0002% by mass, it is difficult to obtain the effect of containing a thickener, and the material separation resistance becomes low. Because there is.

The cement dispersant contained in the premix grout composition is not particularly limited, and a water reducing agent, a high performance water reducing agent, an AE water reducing agent, a high performance AE water reducing agent, a fluidizing agent, or the like can be used, and premixing is easy. In view of this, powder (powder cement dispersant) is preferable. When a powdery high-performance water reducing agent or a powdery high-performance AE water reducing agent is used as a cement dispersant, it is more preferable because the compressive strength of the grout mortar at the age of 28 days is easily 45 N / mm ² or more. The cement dispersant content in the premix grout composition is preferably 0.03% by mass or more and 3% by mass or less because high fluidity is obtained and material separation is difficult.

    The foaming agent contained in the premix grout composition is not particularly limited as long as it is a powder foaming agent, and may be any powder that generates gas after being kneaded with water. By this foaming action, the settlement phenomenon of the grout mortar can be prevented and integrated with members such as the existing wall 4, the existing pillar 1 and the beam 2. That is, non-shrinkage is obtained. The content of the foaming agent in the premix grout composition is preferably 0.0002% by mass or more and 0.03% by mass or less. If the amount is less than 0.0002% by mass, it is difficult to obtain the effect of the foaming agent. If the amount exceeds 0.03% by mass, excessive expansion occurs particularly in a high-temperature environment, and there is a concern about a decrease in compressive strength.

    Aggregates contained in the premix grout composition contain beans gravel having a particle size of more than 4 mm and not more than 7 mm. Moreover, the said aggregate contains the aggregate whose particle size is smaller than bean gravel other than bean gravel. Examples of the aggregate having a small particle size include river sand, land sand, sea sand, crushed sand, silica sand, artificial aggregate, and slag aggregate. As the above-mentioned aggregate, a lightweight aggregate having a large water absorption rate is not so preferable because drying shrinkage becomes large.

    The aggregate preferably has a bean gravel content of 15% by mass or more and 45% by mass or less. If the bean gravel content is less than 15% by mass, the temperature increase due to drying shrinkage and heat of hydration increases, and if it exceeds 45% by mass, the material separation resistance is poor and bleeding is likely to occur. . In addition, as for the said aggregate, it is more preferable in the content rate of beans gravel being 16 mass% or more and 40 mass%.

    In addition, since the above-mentioned aggregate is easy to obtain high fluidity and excellent in material separation resistance, the content ratio of particles having a particle diameter of more than 0.3 mm and 4 mm or less is 40% by mass or more and 65% by mass or less. The content of particles having a diameter of more than 0.3 mm and not more than 2.5 mm is 30% by mass to 55% by mass, the content of particles having a particle size of 0.3 mm or less is 1% by mass to 45% by mass, Is preferably 10% by mass or less.

    Drying shrinkage is such that the content ratio (a / B) of the aggregate mass (a) to the mass (B) of the binder contained in the premix grout composition is 1.8 to 3.0 in terms of mass ratio. It is preferable because it is small and difficult to separate, and the temperature rise due to heat of hydration is small. If it is less than 1.8, the amount of unit cement increases, so the drying shrinkage reducing effect and the effect of reducing hydration heat generation are poor, and if it exceeds 3.0, the material separation resistance is inferior and bleeding is likely to occur. Because. It is more preferable that a / B is 2.2 or more and 2.6 or less because drying shrinkage is small, material separation is difficult, and temperature rise due to heat of hydration is small. Here, the binder (B) includes cement, gypsum, pozzolanes such as silica fume and metakaolin, and latent hydraulic substances such as blast furnace slag powder and an expanding material.

    As described above, the seismic reinforcement wall 10 of Embodiment 1 is a hardened product of a high-strength grout material in which the wall body 14 made of concrete in the conventional construction method is composed of the premix grout composition and water. It consists of As described above, since the high-strength grout material contains an expansion material and a foaming agent, the high-strength grout material hardly sinks when cured, and has a non-shrink property similar to a non-shrink mortar. On the other hand, since the high-strength grout material contains bean gravel, the temperature rise due to drying shrinkage and heat of hydration of the cured product is significantly smaller than that of a general non-shrink mortar. Therefore, in the conventional construction method, since concrete sinks, as shown in FIG. 3, after placing the concrete wall body 20, non-shrink mortar is injected between the concrete wall body 20 and the existing beam 2. The non-shrink mortar wall body 30 is placed, and the concrete wall body 20 and the non-shrink mortar wall body 30 constitute the wall body of the earthquake-proof reinforcement wall. In the first embodiment, the high-strength grout material is cured. The wall body 14 of the earthquake-proof reinforcement wall 10 can be comprised only with a thing.

In addition, it has been confirmed that the hardened | cured material of the high intensity | strength grout material of the above compositions has a high compressive strength of 50 N / mm < ² > or more by the compressive strength test of the material age 28 days. This compressive strength is at least twice the compressive strength (about 24 N / mm ² ) of “Ready mixed concrete” defined in JISA5308. Therefore, the wall body 14 of the seismic reinforcement wall 10 is made of a hardened material of such a high strength grout material having a very high compressive strength, so that the wall body is composed of the concrete wall body 20 and the non-shrink mortar wall body 30. The seismic reinforcement wall 10 having the same proof strength with a thin wall thickness t1 (see FIG. 2) can be constructed as compared with the seismic reinforcement wall constructed by the conventional method.

    Specifically, as shown in FIG. 3, the wall thickness t2 of the seismic reinforcing wall of the conventional method is 250 mm, whereas the seismic reinforcing wall 10 of the present embodiment has the wall of the seismic reinforcing wall of the conventional method. It is possible to construct the seismic reinforcing wall 10 having equivalent strength with a wall thickness t1 (= 125 mm) which is half of the thickness t2.

-Seismic reinforcement method-
Below, the earthquake-proof reinforcement construction method which increases the possession strength of the existing building by building the earthquake-proof reinforcement wall 10 in the frame 3 based on the process chart of FIG. 4 is demonstrated. In the process chart of FIG. 4, the construction period (day) is shown in the upper stage, the processes of the conventional construction method are shown in chronological order in the middle stage, and the processes of the seismic strengthening construction method (main construction method) according to the present invention in the lower stage. They are shown in order.

    As shown in FIG. 4, the seismic reinforcement method includes an anchor attachment process, a bar arrangement process, a formwork installation process, a sealing process, a placing process, a curing process, and a formwork dismantling process. . The anchor attachment process, the bar arrangement process, the mold installation process, the sealing process, the placing process, the curing process, and the mold disassembly process are performed in this order.

    In the anchor attachment process, a plurality of anchor members 11 are attached to the pair of pillars 1 and the pair of beams 2 constituting the frame 3 so as to protrude into the frame 3. Specifically, with respect to the pair of columns 1 and the pair of beams 2, a plurality of anchor members 11 are respectively embedded in the column 1 or the beam 2 at the tip side of the anchor bars, and the remaining portions are in the frame 3. Attach to protrude.

    In the reinforcing bar arrangement process, a plurality of reinforcing bars 12 are arranged vertically and horizontally in the frame 3. Specifically, a plurality of vertical bars 12a are arranged at predetermined intervals in the horizontal direction from the left end to the right end in the frame 3, and a plurality of horizontal bars 12b extending in the horizontal direction are arranged from the upper end to the lower end in the frame 3. Are arranged at predetermined intervals in the vertical direction. In the first embodiment, the split reinforcement bars 13 are disposed at the joint portion of the seismic reinforcement wall 10 with the frame 3 (the outer edge part of the earthquake resistance reinforcement wall 10) in the bar arrangement process.

    In the mold installation process, a mold for configuring the wall body 14 that includes the plurality of reinforcing bars 12 arranged in the bar arrangement process is installed. The formwork is such that the thickness of the seismic reinforcement wall 10 is 130 mm or less, and in the subsequent placing step, the high-strength grout material does not exceed the beam width w in the beam width direction of the pair of beams 2. Installed to be filled. The mold is provided with an injection hole for injecting a high-strength grout material constituting the wall body 14 and a plurality of air vent holes.

    In the sealing step, the gap between the connecting portions of the plate-like members constituting the mold is filled with the sealing member so that the high-strength grout material does not leak from the gap in the placing step.

    In the casting process, a high-strength grout material is filled into the mold from the injection hole formed in the mold installed in the mold installation process using a grout pump. At this time, the high-strength grout material is filled in a range not exceeding the beam width w in the beam width direction of the pair of beams 2 so that the thickness of the earthquake-proof reinforcement wall 10 is 130 mm or less by the mold. . In addition, a high intensity | strength grout material is manufactured by knead | mixing a premix grout composition and water with a mixer in the construction site as mentioned above. In addition, in this embodiment, the high intensity | strength grout material manufactured by knead | mixing with 8 mass parts or more and 20 mass parts or less of water with respect to 100 mass parts of premix grout compositions is inject | poured.

    In the curing process, the high-strength grout material cast in the casting process is cured without giving vibration.

    In the mold disassembly process, the curing process is terminated when the high-strength grout material is cured, and the mold is disassembled.

    The earthquake-proof reinforcement wall 10 along the existing wall 4 is constructed in the frame 3 by the above process. Thus, in the seismic reinforcement method according to the present invention, the placing process is only required once. Therefore, the construction period can be shortened as compared with the conventional construction method in which it is necessary to perform the placing process twice by placing concrete and non-shrink mortar.

    Specifically, as shown in FIG. 4, the conventional construction method includes an anchor attachment process, a bar arrangement process, a first formwork installation process, a first placement process, a first curing process, and a second mold. A frame installation step, a sealing step, a second placing step, a second curing step, and a mold form disassembling step were provided.

    The first formwork installation process is a process of installing a formwork for placing concrete, the first placement process is a process of placing concrete, and the first curing process is a process of hardening the concrete. is there. On the other hand, the second mold installation step is a step of installing a formwork for non-shrink mortar placement, the second placement step is a step of placing non-shrink mortar, and the second curing step is This is a step of curing the non-shrink mortar.

    As shown in FIG. 3, in the conventional method, in the first placing step, after placing the concrete wall 20 up to a height of 200 mm below the existing beam 2, the concrete wall 20 and the existing beam 2 are placed. The non-shrinking mortar is injected between them to drive the non-shrinking mortar wall 30.

    Thus, in the conventional construction method, in order to place concrete and non-shrink mortar, it was necessary to perform the mold installation step, the placement step, and the curing step twice. On the other hand, in the seismic strengthening method (main method) according to the present invention, the work period can be greatly shortened because it is only necessary to perform the mold installation process, the placing process, and the curing process only once. In FIG. 4, according to the present construction method, the construction period can be shortened by 3 days compared to the conventional construction method.

    In addition, as shown in FIG. 3, when the beam width w of the existing beam 2 is narrow, the end face on the reinforcement side of the existing wall 4 (the side on which the seismic reinforcement wall 10 is constructed in the horizontal direction perpendicular to the existing wall 4) Since the distance w1 between the end of the existing beam 2 and the end face on the reinforcement side is short, the seismic reinforcement wall protrudes from the upper and lower existing beams 2 to the reinforcement side in the conventional seismic reinforcement wall having a thick wall thickness t2. Therefore, in such a case, it is necessary to increase the number of beams 2 by the width Δw so that the seismic reinforcement walls do not protrude from the upper and lower beams 2. In this case, for the upper beam 2, the non-shrink mortar wall 30 may be extended upward so that a non-shrink mortar beam having a width Δw is formed on the side of the existing beam 2. 2 (the beam 2 behind the downstairs ceiling 5), a side wall of the beam 2 is provided with a formwork separately from the seismic reinforcement wall and filled with non-shrinking mortar 40. Must be increased. Since various wirings, pipes, ducts and the like are arranged on the back of the ceiling 5, before the non-shrink mortar beam body 40 is added to the side of the lower beam 2, these wirings, pipes are arranged. In some cases, it may be necessary to move ducts. As described above, in the conventional construction method, since the seismic reinforcement wall becomes thick, it is often necessary to increase the number of beams, and it is necessary to perform various operations in addition to the construction of the earthquake resistance reinforcement wall, resulting in a longer construction period. There was a fear.

    On the other hand, in the seismic reinforcement construction method (main construction method) according to the present invention, as described above, the seismic reinforcement wall 10 having a thin wall thickness and equivalent strength can be constructed as compared with the seismic reinforcement wall by the conventional construction method. . Specifically, the thickness t1 of the seismic reinforcement wall 10 can be reduced to 130 mm or less. Therefore, in this construction method, it is possible to omit the extra striking of the beam 2 by the non-shrink mortar in the placing process, and it is not necessary to perform various operations accompanying the extra striking of the beam. Can be shortened.

-Effect of Embodiment 1-
As described above, according to the first embodiment, the wall body 14 of the seismic reinforcement wall 10 is not made of concrete like a conventional reinforced concrete seismic reinforcement wall, but cement, expansion material, and pea gravel are used. It was decided to comprise the hardened | cured material of the high intensity | strength grout material comprised with the premix grout composition containing the aggregate containing, a cement dispersing agent, a thickener, and a foaming agent, and water. Since the high-strength grout material contains an expansion material and a foaming agent, the high-strength grout material hardly sinks when cured, and has the same non-shrinkage property as a non-shrink mortar. On the other hand, since the high-strength grout material contains bean gravel, the temperature rise due to drying shrinkage and heat of hydration of the cured product is significantly smaller than that of a general non-shrink mortar. Therefore, in the conventional construction method, since concrete sinks, after placing the concrete wall 20 as shown in FIG. 3, non-shrinking mortar is injected between the concrete wall 20 and the existing beam 2. The non-shrink mortar wall body 30 is placed, and the concrete wall body 20 and the non-shrink mortar wall body 30 constitute the wall body of the earthquake-proof reinforcement wall. In the first embodiment, the high-strength grout material is cured. The wall body 14 of the earthquake-proof reinforcement wall 10 can be comprised only with a thing. Therefore, according to the seismic reinforcement method (main method) for constructing such a seismic reinforcement wall 10, the non-shrink mortar wall body 30 made of non-shrink mortar is placed after the concrete wall body 20 is placed as in the conventional method. Therefore, the construction period for constructing the earthquake-proof reinforcement wall 10 can be greatly shortened. Therefore, according to the first embodiment, it is possible to provide a seismic reinforcement method capable of constructing the seismic reinforcement wall 10 in a shorter construction period than conventional ones.

Further, according to the first embodiment, the seismic reinforcing wall is made of a hardened material of a high strength grout material having a compressive strength more than twice the compressive strength (about 24 N / mm ² ) of “Ready mixed concrete” defined in JIS A5308. Therefore, the seismic reinforcing wall 10 having the same strength as the wall thickness t1 can be constructed as compared with the seismic reinforcing wall according to the conventional method. In addition, since the gravel material used is bean gravel, the aggregate particles are rounded, and even when the maximum size of the aggregate is as small as 7 mm or less, the slump flow is 500 mm or more. High fluidity can be secured. From this, the thickness of the said earthquake-proof reinforcement wall 10 can be made thin with 130 mm or less. Therefore, even when the beam width w of the existing beam 2 is narrow and the distance w1 between the end surface on the reinforcement side of the existing wall 4 and the end surface on the reinforcement side of the existing beam is short, the seismic reinforcement wall 10 extends from the existing beam 2 in the beam width direction. It can be constructed so as not to protrude, and the extra striking of the beam with non-shrink mortar can be omitted. Therefore, it is not necessary to move various wirings, pipes, ducts and the like on the back of the ceiling, and the construction period for constructing the earthquake-resistant reinforcing wall 10 can be greatly shortened from this point.

    Furthermore, according to the first embodiment, as described above, it is possible to construct the earthquake-resistant reinforcing wall 10 having the same strength as the wall thickness t1 that is thinner than the earthquake-resistant reinforcing wall according to the conventional method. When performing seismic reinforcement of an object, an increase in the weight of the building due to the seismic reinforcement can be reduced. Since the amount of reinforcement of the entire building can be reduced by reducing the increase in weight, the cost for seismic reinforcement can be reduced.

Further, according to the first embodiment, as described above, the high-strength grout material having a compressive strength more than twice the compressive strength (about 24 N / mm ² ) of “ready mixed concrete” defined in JIS A5308. Since the wall 14 of the seismic reinforcement wall 10 is composed of objects, the seismic reinforcement wall 10 is constructed with a wall thickness equivalent to that of a conventional seismic reinforcement wall when performing seismic reinforcement of a multi-level building. Since the number of reinforcement points can be reduced, the cost required for seismic reinforcement can be reduced.

    In addition, since a large amount of concrete is used in the conventional construction method, it is necessary to move a large vehicle such as a concrete pump car. According to the first embodiment, water is added to the premix grout composition and kneaded. Since a high-strength grout material manufactured at the construction site is used, it is not necessary to dispatch a large vehicle. Moreover, since a high-strength grout material can be manufactured near the earthquake-proof reinforcement wall 10 to be expanded, it is not necessary to transport the high-strength grout material. Therefore, according to the seismic reinforcement wall 10 and the seismic reinforcement method of the first embodiment, it is easy even for buildings with narrow sites, buildings with a lot of traffic on the surrounding roads and difficult to design concrete, and high-rise buildings. Can be constructed.

<< Other Embodiments >>
In the said Embodiment 1, although the earthquake-resistant reinforcement construction method which builds the earthquake-resistant reinforcement wall 10 along the existing wall 4 in the frame 3 was demonstrated, the earthquake-resistant reinforcement wall which concerns on this invention and the earthquake-resistant reinforcement construction method which constructs it are the above-mentioned. The present invention is not limited to this, and can also be applied to the case where a seismic reinforcement wall 10 is newly added to the frame 3.

    As described above, the present invention is useful for the seismic reinforcement method.

1 pillar
2 beams
3 frames
4 Existing walls
10 Seismic reinforcement wall
11 Anchor member
12 Reinforcing bars
14 Wall

Claims (2)

A seismic reinforcement method for increasing the holding strength of the building by constructing a seismic reinforcement wall in a frame surrounded by a pair of left and right pillars and a pair of upper and lower beams of the building,
An anchor attachment step of attaching a plurality of anchor members to the frame so as to protrude into the frame;
A bar arrangement process for arranging a plurality of reinforcing bars vertically and horizontally in the frame,
A formwork installation process for installing a formwork for constituting the seismic reinforcement wall in the frame,
A high-strength grout material composed of a grout composition containing cement, an expanding material, an aggregate containing bean gravel, a cement dispersant, a thickener, and a foaming agent and water is added to the above-mentioned formwork. A placing step of filling a range not exceeding the beam width in the beam width direction of the beam so that the wall thickness is 130 mm or less;
Curing step for curing the high-strength grout material filled in the mold in the placing step to constitute a wall body containing the plurality of reinforcing bars,
After the curing step, comprising a formwork dismantling process for dismantling the formwork,
The above-mentioned form installation process, the above-mentioned placing process, and the above-mentioned curing process are each performed only once, respectively. In claim 1,
In the placing step, the high-strength grout material is filled into the formwork without increasing the number of beams by non-shrinking mortar.

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