JP7587789B2 - Wall structure, construction method of wall structure, and design method of wall structure - Google Patents

Description

The present invention relates to a wall structure having an opening, a construction method for the wall structure, and a design method for the wall structure.

For example, Patent Document 1 discloses a technique for improving the strength of existing walls in reinforced concrete buildings by attaching H-shaped steel frames to columns and beams. Another technique for seismic reinforcement is to add reinforced concrete walls to existing walls.

JP 2004-169504 A

However, existing walls that are the subject of seismic reinforcement may have openings. Figure 15 is a graph showing an example of the relationship between the opening ratio and safety margin for existing walls with openings. The safety margin is a value calculated under specified conditions, with the wall strength calculated by the diagnostic criteria formula specified by the Japan Building Disaster Prevention Association as the denominator and the wall strength calculated by experiments as the numerator. As shown in Figure 15, the safety margin decreases as the opening ratio of the opening increases, and drops significantly when it exceeds 0.4. For this reason, technology is required for seismic reinforcement using additional wall sections to improve the wall strength while leaving the openings in the existing wall. Note that this demand is not limited to wall structures in which additional wall sections are added to existing walls, but is also common to wall structures that are newly constructed to be in contact with columns or beams, for example.

The wall structure that solves the above problem has a wall made of a cement composition having a predetermined thickness, a rectangular opening provided on the inside in an in-plane direction perpendicular to the thickness direction of the wall, a rectangular metal frame material that surrounds the opening and is joined to the inside of the cement composition of the wall, and a metal plate material that is fixed to the corners of the frame material and embedded in the cement composition of the wall.

The wall construction method that solves the above problem is a method for constructing a wall structure having a rectangular opening, and includes a frame installation process for installing a rectangular metal frame material that surrounds the opening and has plate materials fixed to the corners, and a wall formation process for pouring a cement composition around the frame material so that the plate materials are embedded, thereby forming a wall portion of the cement composition.

According to the above configuration, the frame material surrounding the opening is joined to the inside of the cement composition of the wall, and the plate material fixed to the corners of the frame material is embedded, thereby improving the wall strength of the wall structure with an opening.

In the wall structure having the above-described configuration, it is preferable that the wall structure further includes reinforcing bars embedded in the cement composition of the wall portion around the periphery of the frame material, and that the cement composition contains concrete.
The construction method for a wall structure having the above-described configuration preferably further includes a reinforcement process for arranging steel bars around the frame material between the frame material installation process and the wall formation process, and in the wall formation process, concrete is poured around the frame material so that the plate material is embedded, to form a wall made of reinforced concrete.

According to the above-mentioned configuration, since the wall portion is made of reinforced concrete, the bearing strength of the wall portion can be effectively improved.
In the aforementioned configuration, an aperture ratio of the opening may exceed 0.4.

As in the above configuration, when the opening ratio of the opening exceeds 0.4, the wall strength of the wall structure can be effectively improved.
In the above configuration, it is preferable that the plate material is embedded so as to extend parallel to the in-plane direction.

According to the above-mentioned configuration, since the plate members are parallel to the in-plane direction, mechanical loads can be effectively transmitted between the vertical frame members and the horizontal frame members of the frame member.
In the above configuration, an existing structure portion may be provided on the outer side of the wall portion in the in-plane direction so as to be in contact with the wall portion.

As in the above configuration, the wall structure can be provided with a wall portion in contact with the existing structural portion.
In the above configuration, it is preferable that the wall portion and the existing structural portion are joined via a post-installed anchor that is provided in advance in the existing structural portion.

According to the above-mentioned configuration, the wall portion can be joined more firmly to the existing structural portion.
In the above configuration, the wall portion may have an existing wall portion in contact with the wall portion in the thickness direction.

As in the above configuration, by providing the wall portion so as to be in contact with the existing wall portion, it is possible to improve the wall strength of the wall structure including the existing wall and the wall portion.
In the above configuration, it is preferable that a surface of the existing wall portion that comes into contact with the wall portion is roughened or provided with a cotter.

According to the above configuration, the existing wall portion and the wall portion can be more firmly integrated.
A design method for a wall structure that solves the above-mentioned problems is a design method for a wall structure composed of an existing wall section having an existing rectangular opening and an additional wall section joined to the existing wall section, wherein the additional wall section has a wall section of cement composition having a predetermined thickness, a rectangular metal frame material having a frame material opening that overlaps with the existing opening and joined to the inside of the cement composition of the wall section, and a metal plate material fixed to the corners of the frame material and embedded in the cement composition of the wall section, and the wall strength after addition of the additional wall section is determined in advance for each representative shape of the existing wall section, and the wall strength of the wall structure is calculated based on the shape of the existing wall section and the wall strength determined in advance.

With the above configuration, the wall strength after the additional wall section is installed can be calculated based on the shape of the existing wall section and the wall strength determined in advance, making it possible to quickly determine whether the wall strength of the wall structure has reached the target value.

FIG. 1 is a front view showing a schematic configuration of an embodiment of a wall structure. Front view of the frame body. 1 is a flowchart showing one embodiment of a construction method for a wall structure. FIG. 13 is a front view showing a state after the post-installed anchor installation process is completed. A front view showing the state after the frame material installation process is completed. Cross-sectional view taken along line 6-6. FIG. FIG. 13 is a front view showing a state in which the reinforcement process is completed. A front view showing the state after the first formwork installation process is completed. A front view showing the state after the second formwork installation process is completed. A front view showing the state after the second casting process is completed. 1 is a flow chart illustrating an embodiment of a method for designing a wall structure. FIG. 13 is a diagram showing an example of the structure of a frame body in a modified example. FIG. 13 is a diagram showing an example of the structure of a frame body in a modified example. 13 is a graph showing an example of the relationship between the aperture ratio and the safety margin in a conventional example.

An embodiment of a wall structure, a method for constructing a wall structure, and a method for designing a wall structure will be described with reference to FIGS. 1 to 12.
As shown in FIG. 1, a wall structure 10 is provided in a building 11. The structural type of the building 11 is reinforced concrete construction or steel-reinforced concrete construction. The building 11 includes a column 12, a beam 13, and an existing wall section 14. The column 12 and the beam 13 are existing structural sections. The column 12 and the beam 13 are connected to each other via a joint section 15. The existing wall section 14 is provided so as to contact the column 12 and the beam 13, and has an existing opening section 16 that is rectangular in front view. In this embodiment, the wall structure 10 is composed of the existing wall section 14 and an additional wall section 20 that contacts a contact surface 14a of the existing wall section 14.

The additional wall section 20 has a wall section 21 and a frame body 22. The additional wall section 20 has a rectangular opening 23 on the inside in the in-plane direction perpendicular to the thickness direction of the wall section 21, which overlaps with the existing opening 16 in a front view. The wall section 21 is a cement composition having a predetermined thickness. In the wall section 21 of this embodiment, vertical and horizontal reinforcement bars, which will be described later, are embedded. The wall section 21 is provided so as to be in contact with the columns 12 and beams 13. The frame body 22 is joined to the inside of the wall section 21 and surrounds the opening 23.

As shown in FIG. 2, the frame body 22 has a frame material 25 and a plate material 26. The frame body 22 may have a connecting material 27 and a stud 28. Each member constituting the frame body 22 is made of metal. The plate material 26, the studs 28, and the connecting material 27 are parts that are embedded in the wall portion 21.

The frame material 25 has a rectangular frame shape when viewed from the front. The frame material 25 has a frame material opening 30 that constitutes the opening 23. The frame material 25 is composed of a pair of vertical members 31 and a pair of horizontal members 32.

Each vertical member 31 and each horizontal member 32 has a rectangular plate shape. Each vertical member 31 and each horizontal member 32 is arranged so that the plate surface is aligned along the thickness direction of the wall portion 21. Each vertical member 31 and each horizontal member 32 has a width approximately equal to the thickness of the wall portion 21. The vertical members 31 and the horizontal members 32 are joined at their intersections by a joining method such as welding. The vertical members 31 and the horizontal members 32 are preferably joined by butt welding. The intersections of the vertical members 31 and the horizontal members 32 form corners of the frame member 25.

The plate material 26 is provided on the outer surface of each corner of the frame material 25 so as to be parallel to the in-plane direction. When viewed from the front, the plate material 26 has an L-shape. The plate material 26 has recesses into which the corners of the frame material 25 fit. After the corners of the plate material 26 are fitted into the recesses, the plate material 26 is joined to the center portions of the vertical members 31 and horizontal members 32 in the width direction by a joining method such as welding.

The connecting members 27 and the studs 28 are rod-shaped members that extend from the outer surface of the frame member 25 toward the outside of the frame member 25. Specifically, the connecting members 27 and the studs 28 extend horizontally from the vertical members 31 and vertically from the horizontal members 32. The connecting members 27 and the studs 28 may each be disposed in the center in the width direction of the vertical members 31 and the horizontal members 32, or may be disposed side by side in the width direction.

The connection members 27 are, for example, reinforcing bars. One end of each of the connection members 27 is joined to each of the vertical members 31 and the horizontal members 32 by a joining method such as welding. The connection members 27 provided on the vertical members 31 constitute horizontal bars embedded in the wall portion 21, and are arranged symmetrically with respect to the center of the vertical members 31 in the vertical direction. The connection members 27 provided on the horizontal members 32 constitute vertical bars embedded in the wall portion 21, and are arranged symmetrically with respect to the center of the horizontal members 32 in the horizontal direction. The arrangement of the connection members 27 refers to the spacing from the intersection of the vertical members 31 and the horizontal members 32 and the spacing from the plate members 26 for the connection members 27 located at the ends. For the other connection members 27, the spacing refers to the spacing from other adjacent connection members 27. The connection members 27 may be provided on the frame members 25 with the same length, or, for example, long connection members 27 and short connection members 27 may be provided alternately.

The studs 28 are, for example, headed studs. The studs 28 are shorter than the connecting members 27. The studs 28 are provided between two adjacent connecting members 27. The ends of the studs 28 opposite the heads are joined to the vertical members 31 or the horizontal members 32 by a joining method such as welding. The studs 28 provided on the vertical members 31 are arranged symmetrically with respect to the center of the vertical members 31 in the vertical direction. The studs 28 provided on the horizontal members 32 are arranged symmetrically with respect to the center of the horizontal members 32 in the horizontal direction. The arrangement of the studs 28 refers to the spacing between each stud 28 and the adjacent connecting members 27, the spacing between the studs 28, etc.

(Construction method of wall structure 10)
A method of constructing the wall structure 10 having the above-mentioned wall portion 21 and frame body 22 will be described with reference to Figs.

As shown in Figure 3, the construction method for the wall structure 10 includes a concave-convex formation process (step S101), a post-installed anchor installation process (step S102), a frame material installation process (step S103), a reinforcement process (step S104), and a wall formation process (step S105). The wall formation process (step S105) also includes a first formwork installation process (step S105-1), a first pouring process (step S105-2), a second formwork installation process (step S105-3), and a second pouring process (step S105-4).

In the unevenness forming process (step S101), unevenness is formed on the contact surface 14a of the existing wall portion 14. Specifically, for example, picking or chipping is performed on the existing wall portion 14 to roughen the contact surface 14a of the existing wall portion 14 and form unevenness. Alternatively, for example, multiple cotters are placed on the existing wall portion 14 to form unevenness on the contact surface 14a of the existing wall portion 14.

In the post-installed anchor installation process (step S102), post-installed anchors 40 are installed in a predetermined arrangement on the columns 12 and beams 13, which are the existing structural parts.
Specifically, as shown in Fig. 4, the post-installed anchors 40 extend horizontally from the column 12 and vertically from the beam 13. The post-installed anchors 40 are installed by using holes that are drilled from the inside of the column 12 and the beam 13. The holes for the post-installed anchors 40 are formed in the portion of the additional wall section 20 where the wall section 21 contacts, for example, at a position corresponding to the center in the thickness direction of the wall section 21. Also, for example, the holes are formed so as to be aligned in the thickness direction of the wall section 21.

An example of the arrangement of the post-installed anchors 40 is the distance from the ends of the columns 12 and beams 13 for the post-installed anchors 40 located at the ends. For other post-installed anchors 40, it refers to the distance between adjacent post-installed anchors 40.

It is preferable that a portion of the post-installed anchor 40 installed in the column 12 is provided at a position that is an extension of the connecting member 27 extending from the vertical member 31 of the frame body 22. It is preferable that a portion of the post-installed anchor 40 installed in the beam 13 is provided at a position that is an extension of the connecting member 27 extending from the horizontal member 32 of the frame body 22.

It is preferable that at least one of the post-installed anchors 40 installed in the columns 12 and the post-installed anchors 40 installed in the beams 13 extends to the arrangement area of the connecting members 27 extending from the frame members 25. In this embodiment, the post-installed anchors 40 installed in the beams 13 extend to the arrangement area of the connecting members 27 extending from the cross members 32 of the frame members 25.

The post-installed anchors 40 may have the same protruding length from the column 12 or beam 13, or, for example, post-installed anchors 40 with long protruding lengths and post-installed anchors 40 with short protruding lengths may be installed alternately.

In the frame material installation step (step S103), a frame body 22 having a frame material 25 is installed.
Specifically, as shown in Figures 5 and 6, the frame opening 30 overlaps the existing opening 16, and the frame body 22 is held in a position where the plate material 26 is parallel to the in-plane direction, and then the frame body 22 is connected to a post-installed anchor 40.

As shown in FIG. 7, in this embodiment, the frame body 22 is connected to the post-installed anchor 40 by connecting the connecting member 27 extending from the cross member 32 of the frame body 22 to the post-installed anchor 40 installed on the beam 13 using a connecting device 41 such as a fixing hardware.

In addition, if the post-installed anchors 40 do not extend to the area where the connecting material 27 is arranged, the frame body 22 is connected to the post-installed anchors 40 using, for example, reinforcing bars.
In the reinforcing bar arrangement step (step S104), reinforcing bars are arranged in the portion where the wall portion 21 is to be formed.

Specifically, as shown in FIG. 8, vertical reinforcements 42 are arranged to connect the post-installed anchors 40 that face each other in the vertical direction, and then the vertical reinforcements 42 are connected to the post-installed anchors 40 using a connector (not shown). Also, horizontal reinforcements 43 are arranged to connect the post-installed anchors 40 that face each other in the horizontal direction, and then the horizontal reinforcements 43 are connected to the post-installed anchors 40 using a connector (not shown). Also, horizontal reinforcements 44 are arranged to connect the connecting members 27 and the post-installed anchors 40 that face each other in the horizontal direction, and then the horizontal reinforcements 44 are connected to the connecting members 27 and the post-installed anchors 40 using a connector (not shown). The connecting members 27, the installation anchors 40, and the vertical reinforcements 42 and the horizontal reinforcements 43, 44 may be tied together at their intersections with tie wires.

In the wall forming step (step S105), first, a first formwork setting step (step S105-1) is performed. In the first formwork setting step (step S105-1), a first formwork is set.
As shown in Fig. 9, the first formwork 51 is provided so as to contact the columns 12 on both the left and right sides and the lower beam 13 and to form a gap 52 of, for example, about 20 cm between the first formwork 51 and the upper beam 13. The first formwork 51 has a formwork opening 53 that is located inside the frame material opening 30 when viewed from the front. The first formwork 51 is composed of, for example, a plurality of wooden boards. The first formwork 51 is placed at a position that forms a space between the first formwork 51 and the existing wall portion 14, the space being equal to the thickness of the wall portion 21. The first formwork 51 is supported by supports (not shown) attached to members that constitute the building 11, such as the columns 12 and the beams 13.

In the first casting step (step S105-2), a first cement composition is poured into the space between the existing wall portion 14 and the first formwork 51 and allowed to harden.
Specifically, the first cement composition is poured into the space between the existing wall portion 14 and the first formwork 51 through the above-mentioned gap 52. The first cement composition is poured until it reaches the vicinity of the upper edge of the first formwork 51. The first cement composition is deaerated by being vibrated by a vibrator or the like inserted through the gap 52. An example of the first cement composition is ordinary concrete.

As shown in FIG. 10, in the first casting step, the first formwork 51 is removed after the first cement composition has hardened. When the first formwork 51 is removed, the first wall portion 21A is exposed. When the first wall portion 21A is formed, the existing opening 16 and the frame material opening 30 form the opening 23 of the wall structure 10. It is preferable that the first wall portion 21A is formed so that only the base portions of the post-installed anchors 40 installed on the upper beam 13 are exposed in a front view. This allows all the post-installed anchors 40 to be connected to the first wall portion 21A.

In the second formwork installation step (step S105-3), a second formwork is installed.
As shown in FIG. 10, the second formwork 55 has a rectangular shape when viewed from the front. The second formwork 55 is provided so as to be in contact with the columns 12 on both the left and right sides and the upper beam 13. The second formwork 55 is provided with a pouring port (not shown) for pouring the second cement composition. The pouring port is provided in a position close to the upper beam 13. The second formwork 55 is made of, for example, a plurality of wooden boards. The second formwork 55 is disposed in a position that forms a space between the existing wall portion 14 and the second formwork 55 for the thickness of the wall portion 21. The second formwork 55 is supported by a support (not shown) attached to a member constituting the building 11, such as the column 12 or the beam 13.

In the second casting step (step S105-4), a second cement composition is poured into the space between the existing wall portion 14 and the second formwork 55 and allowed to harden. This forms the second wall portion 21B that constitutes the remainder of the wall portion 21.

Specifically, the second cement composition is poured into the space between the existing wall portion 14 and the second formwork 55 through a pouring port provided in the second formwork 55. The second cement composition is poured so that it overflows from the pouring port. The second cement composition is deaerated by hitting the second formwork 55 from the front side with a mallet or the like. One example of the second cement composition is a flowable non-shrink mortar.

As shown in FIG. 11, in the second casting step, the second formwork 55 is removed after the second cement composition hardens. When the second formwork 55 is removed, the wall portion 21 in which the first wall portion 21A and the second wall portion 21B are integrated is exposed. The wall portion 21 is joined to the existing wall portion 14 in a state where it engages with the unevenness formed on the contact surface 14a of the existing wall portion 14. In this way, the additional wall portion 20 is joined to the existing wall portion 14 to form the wall structure 10.

(Action)
In the wall structure 10, an existing wall section 14 is reinforced by an additional wall section 20.
In the additional wall portion 20, the compressive force can be borne by the wall portion 21 made of a cement composition, which is resistant to compression, and the tensile force can be borne by the metal frame body 22, the post-installed anchors 40, and the vertical reinforcements 42 and the horizontal reinforcements 43, 44, which are resistant to tension. The opening 23 of the wall structure 10 is formed by a rectangular frame material 25. The frame material 25 is fixed to the wall portion 21 via studs 28, and the corners are reinforced by plate materials 26. This makes it possible to make the corners of the frame material 25 less likely to deform even if a load acts on the wall structure 10 through the columns 12 and beams 13 during an earthquake or the like. And, since the additional wall portion 20 is joined to the existing wall portion 14, in the wall structure 10, it is possible to make the periphery of the opening 23, particularly the vicinity of the corners of the opening 23, less likely to deform. This reduces the energy of the compressive force lost due to deformation, and therefore the compressive force acting on the wall portion 21 made of a cement composition can be increased. As a result, the wall strength of the wall structure 10 can be improved.

(Method of designing the wall structure 10)
A method for designing the above-mentioned wall structure 10 will be described with reference to Fig. 12. In this design method, when reinforcing the existing wall section 14, the wall strength when the additional wall section 20 is added is calculated, and it is determined whether the calculated wall strength satisfies a target value.

As shown in FIG. 12, first, it is determined whether the building 11 satisfies the application conditions (step S201).
The applicable condition is that the building 11 itself is made of reinforced concrete or steel-reinforced concrete.

For columns 12, various strength conditions such as cross-sectional dimensions, ratio of main reinforcement to cross-section, hoop ratio, concrete strength, and standard strength of main reinforcement and hoops must meet specified standard values.

For beam 13, various strength conditions such as cross-sectional dimensions, ratio of main reinforcement to cross-section, stirrup ratio, concrete strength, and standard strength of main reinforcement and hoops must meet specified standard values.

The existing wall section 14 must satisfy predetermined standard values for shape conditions such as the opening position, opening ratio, and wall shape, as well as various strength conditions such as thickness, concrete strength, vertical and horizontal reinforcement ratios, and standard strength of reinforcing bars.

If the applicable condition is satisfied (step S201: YES), it is determined whether the existing wall portion 14 is a single-layer wall (step S202).
If the existing wall section 14 is a single-layer wall (step S202: YES), the wall strength is calculated using a quick reference table. The quick reference table specifies the wall strength after the additional wall section 20 is added for each of the representative shape conditions of the existing wall section 14. The wall strength specified in the quick reference table is a value based on the results of a simulation. Specifically, it is a value based on the results of an FEM analysis performed on the case where the additional wall section 20 is added to the existing wall section 14.

The FEM analysis is performed using standard values of strength conditions for the columns 12, beams 13, and existing wall section 14. For the additional wall section 20, the FEM analysis is performed using predetermined standard values for additional construction conditions such as the thickness of the wall section 21 (e.g., about two types), the strength of the wall section 21 (strength of the cement composition), the vertical and horizontal reinforcement ratios, the standard strength of the rebar, the material, thickness, and width (= thickness of the wall section 21) of the vertical members 31 and horizontal members 32, and the material and length of the studs 28.

If the existing wall section 14 is a single-layer wall (step S202: YES), the wall strength is calculated based on the shape of the existing wall section 14 and the look-up table (step S203). Specifically, the wall strength is calculated by selecting multiple wall strengths with shape conditions similar to the shape of the existing wall section 14 to which the additional wall section 20 is to be added, and linearly interpolating the multiple selected wall strengths. Then, if the wall strength calculated using the look-up table is greater than the target value, the additional wall section 20 is designed according to the additional wall conditions.

If the existing wall section 14 is a multi-story wall (step S202: NO), the safety margin of the wall strength is calculated based on a quick reference table for wall strength based on the diagnostic criteria formula defined by the Japan Building Disaster Prevention Association (step S204). If the calculated safety margin is greater than a predetermined threshold and this condition is met (step S205: YES), the wall strength is calculated based on the diagnostic criteria formula even if the opening ratio exceeds 0.4 (step S206). The reinforced wall section 20 is then designed according to the condition that the wall strength based on the diagnostic criteria formula is greater than the target value.

If the building 11 does not satisfy the application conditions (step S201: NO) and if the safety margin is equal to or less than a predetermined threshold (step S205: NO), an individual FEM analysis is performed (step S207), and the wall strength is calculated based on the analysis results (step S208). If the wall strength based on the analysis results is greater than the target value, the reinforcement wall section 20 is designed according to the conditions for the reinforcement wall section 20 set during the analysis.

The effects of this embodiment will be described.
(1) In the wall structure 10, the reinforced wall section 20 is provided so as to be in contact with the existing wall section 14. This makes it difficult for the wall structure 10 to deform even if a load acts through the columns 12 and beams 13 during an earthquake or the like, thereby improving the wall strength of the wall structure 10.

(2) Since the first wall portion 21A is made of reinforced concrete, the wall strength of the wall structure 10 can be effectively increased.
(3) Even if the opening ratio of the existing opening 16 exceeds 0.4, the wall strength of the wall structure 10 can be effectively increased.

(4) In the frame body 22, plate materials 26 that reinforce the corners of the frame material 25 are embedded parallel to the in-plane direction. This makes it possible to effectively utilize the strength of the plate materials 26 against forces that tend to deform the corners of the frame material 25 along the in-plane direction.

(5) The wall section 21 of the reinforced wall section 20 is joined to the existing structural components, the columns 12 and beams 13, via post-installed anchors 40. This allows the wall section 21 to be more firmly joined to the columns 12 and beams 13.

(6) The contact surface 14a of the existing wall portion 14 is uneven. This makes it possible to more firmly integrate the existing wall portion 14 and the boost wall portion 20.
(7) The connection between the frame body 22 and the post-installed anchors 40 can improve the efficiency of load transmission in the additional wall section 20. As a result, the load transmitted from the columns 12 and beams 13 to the additional wall section 20 can be effectively dispersed.

(8) In the frame member 25, the vertical members 31 and the horizontal members 32 are joined by butt welding. This increases the efficiency of force transmission between the vertical members 31 and the horizontal members 32.

(9) Since the stud 28 is shorter than the connecting material 27, it is easier to secure space for the connection work between the connecting material 27 and the post-installed anchor 40.
(10) Since the studs 28 are headed studs, the frame material 25 and the wall portion 21 can be joined more firmly.

(11) The wall portion 21 of the reinforcement wall portion 20 is composed of a first wall portion 21A and a second wall portion 21B. This allows the wall portion 21 to be formed so as to be in reliable contact with the columns 12 and beams 13.

(12) The wall strength of the wall structure 10 can be easily calculated by using the quick reference table. As a result, it can be quickly determined whether the wall strength of the wall structure 10 has reached the target value.

This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.
The contact surface 14a of the existing wall portion 14 does not need to have any projections or recesses.

The wall structure 10 is not limited to being composed of the existing wall section 14 and the additional wall section 20 .
For example, the wall structure 10 may be a newly constructed wall that is in contact with the existing structural parts, that is, the columns 12 and beams 13 , and has the same structure as the reinforcement wall part 20 .

- The wall structure 10 is not limited to a configuration in which the wall section 21 is joined to the existing structural parts, the columns 12 and beams 13, via post-installed anchors 40. For example, the wall section 21 may be joined to the columns 12 and beams 13 by the hardened cement composition engaging with the irregularities formed on the surfaces of the columns 12 and beams 13.

In the frame body 22, the plate material 26 may be a plate-shaped material that reinforces the corners of the frame material 25. For this reason, the plate material 26 may be provided at an angle with respect to the in-plane direction.
13, the frame body 22 may have only the connecting members 27 as rod-shaped members extending outward from the outer surface of the frame material 25. In this case, it is preferable that the connecting members 27 are provided in place of the above-mentioned studs 28, that is, that the connecting members 27 are provided at narrower intervals than the frame body 22 having the studs 28. This can increase the fixing force of the frame material 25 to the wall portion 21 and makes the frame material 25 less likely to deform when a load is applied to the increased wall portion 20.

- For example, as shown in FIG. 14, the frame body 22 may be configured such that a rib material 57 is joined to the outer surface of the frame material 25. One example of the rib material 57 has a rectangular plate shape and is arranged so that its longitudinal direction runs along the frame material 25. This increases the mechanical strength of the frame body 22 itself, making the frame material 25 less likely to deform when a load is applied to the reinforcement wall section 20.

A single rib material 57 may be provided for the vertical member 31 and the horizontal member 32 to connect the plate material 26, or multiple ribs may be provided to connect the plate materials 26. The rib material 57 may be provided only near the corners of the frame material 25.

The rib material 57 may be arranged in the width direction of the vertical members 31 and horizontal members 32 so as to sandwich a rod-shaped member such as the connecting member 27, or may be arranged only on one side of the rod-shaped member, for example, on the side of the existing wall portion 14.

The rib material 57 may also be disposed in the center of the vertical members 31 and horizontal members 32 in the width direction. In this case, rod-shaped members such as the connecting members 27 may be disposed so as to sandwich the rib material 57 in the width direction of the vertical members 31 and horizontal members 32, or may be disposed alternately on one side and the opposite side of the rib material 57.

- It is preferable that the cross member 32 located on the lower side is provided with an air vent hole that serves as an escape route for air bubbles in the cement composition when pouring in the first pouring step (step S105-2). This makes it less likely that poor filling of the cement composition will occur near the cross member 32 located on the lower side.

- As a construction method that reduces the occurrence of insufficient filling of the cement composition near the cross member 32 located on the lower side, the wall formation process (step S105) may include a process of forming a wall with a height that reaches the cross member 32 located on the lower side.

In one example of this process, similar to the first formwork installation process (step S105-1) to the second casting process (step S105-4) described above, a wall is formed to a height that leaves a gap of about 20 cm between it and the cross member 32 located below, and then a new wall is formed to fill the gap.

The wall structure 10 may have an opening 23 and may be applied to any opening ratio up to about 0.5.
The cement composition is not limited to ordinary concrete or non-shrink mortar. For example, the cement composition may be concrete alone, or may be a cement-based material (fiber-reinforced concrete material) mixed with fibers, such as Slimcrete (registered trademark). In addition, the wall portion 21 does not need to be reinforced.

10...wall structure, 11...building, 12...column as existing structural part, 13...beam as existing structural part, 14...existing wall part, 14a...contact surface, 15...joint part, 16...existing opening, 20...additional wall part, 21...wall part, 21A...first wall part, 21B...second wall part, 22...frame body, 23...opening, 25...frame material, 26...plate material, 27...connecting material, 28...stud, 30...frame material opening, 31...vertical member, 32...horizontal member, 40...construction anchor, 41...connector, 42...vertical reinforcement, 43, 44...horizontal reinforcement, 51...first formwork, 52...gap, 53...formwork opening, 55...second formwork, 57...rib material.

Claims (10)

An existing wall having a rectangular existing opening and a cement composition added wall having a predetermined thickness and joined to the existing wall ;
a rectangular opening provided inside the boost wall portion in an in-plane direction perpendicular to the thickness direction of the boost wall portion and overlapping with the existing opening in a front view ;
A rectangular metal frame material that surrounds the opening and is joined to the inside of the cement composition of the additional wall portion;
A wall structure having a metal plate material fixed to the corners of the frame material and embedded in the cement composition of the reinforcement wall portion. The frame material further includes a reinforcing bar embedded in the cement composition of the reinforcement wall portion around the frame material,
The wall structure of claim 1 , wherein the cement composition comprises concrete. The wall structure according to claim 1 or 2, wherein the aperture ratio of the openings is greater than 0.4. The wall structure according to any one of claims 1 to 3, wherein the plate material is embedded extending parallel to the in-plane direction. The wall structure according to any one of claims 1 to 4, further comprising an existing structure portion in contact with the boost wall portion on the outer side of the boost wall portion in the in-plane direction. The wall structure according to claim 5 , wherein the additional wall portion and the existing structural portion are joined via a post-installed anchor that is provided in advance in the existing structural portion. The wall structure according to any one of claims 1 to 6 , wherein a surface of the existing wall portion in contact with the additional wall portion is roughened or provided with a cotter. A construction method for a wall structure consisting of an existing wall section having a rectangular existing opening and an additional wall section joined to the existing wall section,
a frame installation process for installing a rectangular metal frame having a frame opening that overlaps the existing opening when viewed from the front and a plate material fixed to a corner of the frame;
a wall forming step of pouring a cement composition around the frame material so that the plate material is embedded, and forming the additional wall portion of the cement composition having a predetermined thickness so as to contact the existing wall portion ;
Construction methods for wall structures. Between the frame material installation step and the wall portion formation step, a reinforcing bar arrangement step is further provided for arranging reinforcing bars around the frame material,
In the wall forming step,
The method for constructing a wall structure according to claim 8 , further comprising pouring concrete around the frame material to form a wall portion made of reinforced concrete. A method for designing a wall structure including an existing wall section having a rectangular existing opening and an additional wall section joined to the existing wall section, comprising:
The shot-increasing wall portion is
a wall of a cement composition having a predetermined thickness;
A rectangular metal frame having a frame opening that overlaps the existing opening and is joined to the inside of the cement composition of the wall portion;
and a metal plate material fixed to the corner of the frame material and embedded in the cement composition of the wall portion.
A method for designing a wall structure, comprising: determining in advance the wall strength after the addition of the additional wall section for each representative shape of the existing wall section; and calculating the wall strength of the wall structure based on the shape of the existing wall section and the previously determined wall strength.