JP6952628B2 - Joint structure of half PCa shear wall - Google Patents

Description

The present disclosure relates to a joint structure of half PCa shear walls in a building.

The shear walls of buildings are generally constructed of cast-in-place concrete. In order to shorten the construction period, it is preferable to use a precast concrete (PCa) member, but the large PCa member has a problem of transportability and a problem that the crane for lifting the PCa member becomes large. Further, when a relatively small PCa member is used, the number of joints of the reinforcing bars increases, and if the reinforcing bars are joined by the mechanical joint, the work takes time and there is a problem that the merit of shortening the construction period cannot be sufficiently obtained. Based on these problems, various structures of shear walls using PCa members have been proposed.

For example, in Patent Documents 1 and 2, small PCa blocks are stacked to form a pair of wall bodies facing each other, vertical streaks, horizontal streaks and anchoring streaks are arranged in the internal space thereof, and grout material is placed. The reinforcing wall constructed in the above is described.

Further, Patent Document 3 describes a seismic wall formed by connecting PCa members that are long in the vertical direction and short in the wall plate direction. Since the concrete portion of the PCa member has a pair of wall surface portions forming the wall surface of the wall to be constructed and a connecting portion connecting the central portion of the pair of wall surface portions in a plan view, the concrete portion is H-shaped in a plan view. Is doing. Further, the PCa member has a horizontal streak whose center is embedded in the connecting portion and whose end portion protrudes, and a vertical streak which is embedded in the wall surface portion so that the upper end side protrudes. Cast-in-place concrete is cast in the hollow portion formed between the adjacent PCa members, and the horizontal bars are joined by the horizontal bars of the adjacent PCa members and the lap joint. The vertical bars are joined by mechanical joints.

Further, Non-Patent Document 1 describes a seismic wall using a PCa member in which a pair of PCa plates facing each other are connected by truss bars. Since the vertical and horizontal bars are arranged in the PCa board, the filling property and workability when placing cast-in-place concrete between the pair of PCa boards are good. The vertical bar forms a lap joint in the wall thickness direction with the differential bar protruding from the concrete portion of the PCa beam.

Japanese Unexamined Patent Publication No. 2004-197328 Japanese Unexamined Patent Publication No. 2004-218251 Japanese Unexamined Patent Publication No. 2013-053491

Noriyuki Furuya et al. "Development of Half Precast Shear Wall Frame (Part 1)" Obayashi Technical Research Institute Bulletin, 1992, No.45, pp. 21-28

The reinforcing wall described in Patent Documents 1 and 2 reinforces an existing wall. Therefore, a small PCa block is used, and when applied when constructing a new building, the work of stacking the small PCa blocks is complicated. In the earthquake-resistant wall described in Patent Document 3, it takes time to join the vertical bars with a mechanical joint, and the construction period cannot be sufficiently shortened. In the seismic wall described in Non-Patent Document 1, since the vertical bars and the reinforcing bars are joined so as to overlap each other in the thickness direction of the wall, it is not possible to arrange the horizontal bars connecting the columns and the wall.

In view of such a problem, an object of the present invention is to provide a joint structure of a half PCa shear wall which has good workability and can easily secure a space for a joint.

The joint structure (1,41) of the half PCa shear wall according to at least some embodiments of the present invention is arranged apart from the first PCa member (6a, 42a) and the first PCa member in the wall thickness direction. A first wall portion (2) having a second PCa member (6b, 42b) and a first cast-in-place filler (7a, 46a) including a cast-in-place filler filled between the first PCa member and the second PCa member. , 43) and the second wall portion (4,44) directly or indirectly adjacent to the first wall portion in the first direction along the wall surface of the half PCa shear wall, and the said in the first direction. The third PCa member (6c, 42c) that matches the first PCa member, and the fourth PCa member (6d) that is arranged apart from the third PCa member in the wall thickness direction and matches the second PCa member in the first direction. , 42d), and the second wall portion having second cast-in-place portions (7b, 46b) including the cast-in-place filler filled between the third PCa member and the fourth PCa member, and said first. Each of the fourth PCa member is a concrete portion (8,47) including a main body portion (9) having a predetermined thickness from the outer surface, and any one of vertical bars (11,28) and horizontal bars (12,27). On the other hand, it has first reinforcing bars (11, 27) extending in the first direction and located inside the main body portion, and the first wall portion and the second wall portion are respectively. It has a second reinforcing bar (12, 28) which is one of the vertical bar and the horizontal bar and is orthogonal to the first direction and extends in the second direction along the wall surface of the half PCa shear wall. One end side of the first reinforcing bar of the first wall portion plunges into the second in-situ striking portion, and the first reinforcing bar of the second wall portion becomes the first reinforcing bar of the first wall portion. On the other hand, it is characterized in that it is arranged so as to form a lap joint so as to be displaced in the second direction. Here, "directly adjacent" means a case where the concrete parts of both members are in direct contact with each other, or a case where only a filler such as grout is arranged between both members, and "indirectly" adjacent means. This refers to the case where other members such as beams and floor slabs are interposed between the concrete parts of both members. In addition, "lap joint" includes an empty lap joint.

According to this configuration, since the vertical streaks are joined by the lap joint, the workability is better than the case where the mechanical joint is used. Further, since the portions forming the lap joint in the first reinforcing bar are arranged so as to overlap each other in the second direction, that is, in the vertical direction or the horizontal direction and in the direction orthogonal to the wall thickness direction, there is an empty space in the wall thickness direction. It expands and makes it easier to secure space for the joint of the second reinforcing bar.

At least some embodiments of the present invention are characterized in that, in the above configuration, the first to fourth PCa members each have the second reinforcing bar.

According to this configuration, since the second reinforcing bar is arranged at the PCa manufacturing factory, the work at the construction site can be reduced.

In at least some embodiments of the present invention, in any of the above configurations, the concrete portions (8) of the first to fourth PCa members (6a to 6d) bulge inward from the main body, respectively. It has a plurality of ridges (10) extending along the first direction, the first reinforcing bar is embedded in the ridges, and the ridges of the third and fourth PCa members are. Each of the first and second PCa members is characterized in that they are arranged so as to be offset in the second direction with respect to the ridges.

According to this configuration, a cotter is formed on the joint surface between the PCa member and the concrete portion in each wall portion, and the shear strength is improved. Further, since the first reinforcing bar is embedded in the ridge, it is possible to prevent the first reinforcing bar from being separated from the PCa member during transportation of the PCa member or the like.

At least some embodiments of the present invention are characterized in that, in the above configuration, at least a part (12b) of the second reinforcing bar is arranged so as to penetrate the ridge.

According to this configuration, the second reinforcing bar arranged so as to penetrate the ridge makes it easy for stress to be transmitted at the joint surface between the ridge and the in-situ striking portion.

In at least some embodiments of the present invention, in any of the above configurations having ridges, the first rebar of the second wall is from the ridge to the end on the first wall side. It is characterized by rushing into the second on-site hitting section.

According to this configuration, since the first reinforcing bar crosses the joint surface between the ridge and the second in-situ striking portion, stress is applied at the joint surface between the ridge and the second in-situ striking portion due to the shear friction and the dowel action. It becomes easier to be transmitted.

In at least some embodiments of the present invention, in the first configuration, the first to fourth PCa members (42a to 42d) each support the first reinforcing bar (11) exposed from the concrete portion. Therefore, it is characterized by having a supporting reinforcing bar (48) protruding from the concrete portion.

According to this configuration, since both portions of the first reinforcing bar that form the joint are embedded in the in-situ casting portion 46, stress transmission of the joint of the first reinforcing bar can be performed without going through the joint surface. Further, since the configuration of the PCa member is simplified, the manufacture of the PCa member becomes easy.

In any of the above configurations, at least some embodiments of the present invention include a third wall portion (5,45) or a PCa pillar (29) that is directly or indirectly adjacent to the second wall portion in the second direction. ), And the reinforcing bars (13, 31) protruding in the second direction from the concrete portion (8, 47, 30) of the third wall portion or the PCa column are the second reinforcing bars of the second wall portion. It is characterized in that it rushes into the second in-situ striking portion in order to form a lap joint.

According to this configuration, the reinforcing bars are joined by the lap joint also in the second direction, so that the workability at the construction site is improved.

In at least some embodiments of the present invention, in any of the above configurations, the first reinforcing bar of the first PCa member and the first reinforcing bar of the second PCa member are aligned with each other in the wall thickness direction. It is characterized in that, on one end side thereof, the outer sides of the sill are engaged with each other by a width retaining bar (14).

According to this configuration, the width stop bar can prevent the first PCa member and the second PCa member from moving in a direction away from each other.

In at least some embodiments of the present invention, in any of the above configurations, the first reinforcing bar is the vertical reinforcing bar (11), and the second wall portion is the first wall via the floor slab (3). It is characterized in that it is adjacent to the portion, or the first reinforcing bar is the vertical reinforcing bar, and the second wall portion is directly adjacent to the first wall portion.

According to the former configuration, the first in-situ casting portion and the floor slab can be integrally cast with concrete to improve workability. The latter configuration is suitable for separating concrete between the first cast-in-place part and the floor slab.

According to the present invention, it is possible to provide a joint structure of a half PCa shear wall which has good workability and can easily secure a space for a joint.

(A) plan view and (B) front view showing the joining structure according to the first embodiment. Perspective view showing the joint structure according to the first embodiment A perspective view showing a procedure for constructing a joint structure according to the first embodiment. A perspective view showing a procedure for constructing a joint structure according to the first embodiment. A perspective view showing a procedure for constructing a joint structure according to the first embodiment. A perspective view showing a procedure for constructing a joint structure according to the first embodiment. A perspective view showing a procedure for constructing a joint structure according to the first embodiment. Enlarged sectional view showing the procedure for constructing the joint structure according to the first embodiment. A perspective view showing a procedure for constructing a joint structure according to a first modification of the first embodiment. Perspective view which shows the joining structure which concerns on 1st modification of 1st Embodiment Perspective view which shows the joining structure which concerns on 2nd modification of 1st Embodiment Top view showing the joint structure according to the 2nd modification of the 1st Embodiment Top view showing a joint structure according to a third modification of the first embodiment. Horizontal sectional view showing a joint structure according to a fourth modification of the first embodiment. A perspective view showing a state in which the joint structure according to the fifth modification of the first embodiment is being constructed. A perspective view showing a state in which the joint structure according to the sixth modification of the first embodiment is being constructed. A plan view showing a joint structure according to a seventh modification of the first embodiment. Cross-sectional view showing an example of the structure of the floor slab and the beam in the first embodiment and its modified example. Horizontal cross-sectional view showing a joint example of a concrete portion of a shear wall in the first embodiment and its modified example. A perspective view showing a state in which the joint structure according to the eighth modification of the first embodiment is being constructed. Horizontal cross-sectional view showing the joint structure of the shear wall and the column according to the first embodiment. Horizontal cross-sectional view showing a modified example of the joint structure between the earthquake-resistant wall and the column according to the first embodiment. Perspective view showing a state in the process of constructing the joint structure according to the second embodiment. Plan view showing the earthquake-resistant wall according to the second embodiment

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 and 2 show a joint structure 1 of a half PCa shear wall according to the first embodiment. The joint structure 1 includes a first wall portion 2 that constitutes an earthquake-resistant wall on the lower floor and a second wall portion that constitutes the earthquake-resistant wall on the upper floor and is adjacent to the first wall portion 2 via the floor slab 3 in the vertical direction. 4 and a third wall portion 5 that constitutes an earthquake-resistant wall on the upper floor and is adjacent to the second wall portion 4 in the lateral direction. The first to third wall portions 2, 4, and 5 are walls having a half PCa structure, respectively.

The first wall portion 2 has a first PCa member 6a that defines one surface of the wall and a second PCa that is arranged apart from the first PCa member 6a in the wall thickness direction and defines the other surface of the wall. It has a member 6b and a first cast-in-place portion 7a including a cast-in-place filler filled between the first PCa member a and the second PCa member 6b.

Similarly, the second wall portion 4 is arranged apart from the third PCa member 6c that defines one surface of the wall and the third PCa member 6c in the wall thickness direction to define the other surface of the wall. It has a fourth PCa member 6d and a second cast-in-place portion 7b including a cast-in-place filler filled between the third PCa member 6c and the fourth PCa member 6d. Similarly, the third wall portion 5 is arranged so as to be separated from the fifth PCa member 6e, which defines one surface of the wall, and the fifth PCa member 6e in the wall thickness direction, to form the other surface of the wall. It has a sixth PCa member 6f to be defined, and a third cast-in-place casting portion 7c including a cast-in-place filler filled between the fifth PCa member 6e and the sixth PCa member 6f. Hereinafter, when the first to sixth PCa members 6a to 6f are collectively referred to or not distinguished, they are simply referred to as PCa member 6, and when the first to third in-situ striking portions 7a to 7c are collectively referred to or not distinguished, It is simply referred to as the on-site hitting section 7.

Each PCa member 6 has a concrete portion 8 formed of concrete cast in a factory, and the concrete portion 8 has a flat plate-shaped main body portion 9 having a predetermined thickness from the outer surface and a main body portion 9. It has a plurality of ridges 10 that bulge inward (on the side of the in-situ striking portion 7) and extend along the vertical direction. Further, each PCa member 6 has a vertical bar 11 embedded in the ridge 10 and a horizontal bar 12 embedded in the main body 9. The ridges 10 are arranged at substantially equal intervals, and one vertical bar 11 is embedded in each ridge 10.

The filler of each cast-in-place portion 7 is made of concrete cast at the construction site. When the width of each cast-in-place portion 7 is narrow, grout may be used as the filler instead of concrete.

Between the first wall portion 2 and the second wall portion 4, the vertical bar 11 is joined by a lap joint. The horizontal bar 12 between the second wall portion 4 and the third wall portion 5 is joined by forming a lap joint with the joint bar 13.

3 to 7 show a procedure for constructing the joint structure 1. Hereinafter, the detailed structure of the joint structure 1 will be described along with the construction procedure.

First, each PCa member 6 is manufactured at the factory. Although not shown, for example, a deck plate for a floor or a roof can be used as a formwork for forming the ridge 10. After installing the formwork with the deck plate at the bottom, the vertical bars 11 are arranged along the recesses of the deck plate, the horizontal bars 12 are arranged so as to be orthogonal to the vertical bars 11, and concrete is cast. After curing the concrete, remove the frame. The steel deck plate used as the formwork may be embedded in the earthquake-resistant wall as it is as a structure without removing it. Each manufactured PCa member 6 is transported to a construction site.

FIG. 3 shows a state in which a lower floor structure such as the first wall portion 2 is constructed. The upper end side of the vertical bar 11 provided on the first and second PCa members 6a and 6b protrudes from the concrete portion 8 and the floor slab 3 of the first and second PCa members 6a and 6b. In order to prevent the first and second PCa members 6a and 6b from being displaced so as to be separated from each other, the width retaining bars 14 having hook-shaped ends are aligned with each other in the wall thickness direction. It is preferable to arrange the second PCa member 6b on the upper surface of the floor slab 3 so as to engage with the outside of the vertical bar 11. As shown in FIG. 1, the width retaining bar 14 may be arranged at the upper ends of the wall portions 2, 4 and 5.

FIG. 4 shows a state in which the third and fifth PCa members 6c and 6e are installed. The third PCa member 6c is installed so as to receive the upper portion of the vertical bar 11 of the first PCa member 6a in the recess 15 formed between the ridges 10 and 10 adjacent to each other. Since the vertical streaks 11 are embedded in the ridges 10 except for the upper end portion, the vertical streaks 11 and the ridges 10 of the third PCa member 6c are relative to the vertical streaks 11 and the ridges 10 of the first PCa member 6a, respectively. It is displaced in the lateral direction (extending direction of the horizontal streaks 12). The fifth PCa member e is installed so as to be adjacent to the second PCa member 6c in the lateral direction and to receive the vertical streaks 11 of the lower floors in the recess 15. The outer surfaces of the first, third and fifth PCa members 6a, 6c, 6e (the surface of the concrete portion 8 opposite to the ridge 10) are on the same plane so as to form one surface of the shear wall. To position.

On the inner surface of the third and fifth PCa members 6c and 6e (the surface of the concrete portion 8 on the side where the ridge 10 is formed), the joint bar 13 so as to straddle the third and fifth PCa members 6c and 6e in the lateral direction. Is attached. The joint bar 13 is hooked on a hook (not shown) attached to the inner surface of the concrete portion 8 of the third and fifth PCa members 6c and 6e. For the joint bar 13, for example, a U-shaped reinforcing bar is used, and the upper and lower portions extending in the lateral direction are vacant with respect to the horizontal bars 12 (see FIG. 1) of the third and fifth PCa members 6c and 6e, respectively. It is substantially aligned in the wall thickness direction so as to form a lap joint.

Next, as shown in FIG. 5, the fourth and sixth PCa members 6d and 6f are installed. The surfaces of the 4th and 6th PCa members 6d and 6f are the same as those of the concrete portions 8 of the 3rd and 5th PCa members 6c and 6e so that the surface of the concrete portion 8 on the side where the ridge 10 is formed is on the inside. It faces the surface on the side where the ridge 10 is formed. The positional relationship between the second, fourth, and sixth PCa members 6b, 6d, and 6f is the same as the positional relationship between the first, third, and fifth PCa members 6a, 6c, and 6e. Similar to the inner surfaces of the third and fifth PCa members 6c and 6e, the inner surfaces of the fourth and sixth PCa members 6d and 6f are jointed so as to straddle the fourth and sixth PCa members 6d and 6f in the lateral direction. The muscle 13 is attached.

The vertical streaks 11 and ridges 10 of the third PCa member 6c and the vertical streaks 11 and ridges 10 of the fourth PCa member 6d are aligned with each other in the wall thickness direction. Further, the vertical bars 11 of the third and fourth PCa members 6c and 6d are close to the vertical bars 11 of the first and second PCa members 6a and 6b, which are the targets of the lap joint, respectively, in the lateral direction of the ridge 10. It is preferable that it is close to the end of the. Further, since the vertical streaks 11 on the lower floors are received by the recesses 15 on the upper floors and the vertical streaks 11 on the upper floors are embedded in the ridges, the lower end side of the vertical streaks 11 on the upper floors is the vertical streaks on the lower floors. It is aligned laterally with respect to the upper end side of 11. In order to prevent the third and fourth PCa members 6c and 6d from moving away from each other, the third and fourth PCa members 6c and 6d are fixed to each other with a separator (not shown) or the like used for the mold. You may. The same applies to the fifth and sixth PCa members 6e and 6f.

Next, as shown in FIG. 6, a filler is placed between the third and fourth PCa members 6c and 6d, and between the fifth and sixth PCa members 6e and 6f, and the second and third in-situ casting portions 7b are placed. , 7c is formed. Further, as shown in FIG. 7, the floor slab 3 is constructed on the second and third wall portions 4 and 5.

The filler of the cast-in-place portion 7 and the floor slab 3 on the cast-in-place portion 7 may be cast with the same type of concrete at the same time. In general, the concrete strength required for the floor slab 3 (for example, 30 N / mm ² ) is often lower than the concrete strength required for the shear wall (for example, 48 N / mm ^2). In such a case, concrete of the strength required for the floor slab 3 is used for the filler and the floor slab 3, and concrete having a higher strength than that required for the shear wall is used for the concrete portion 8 of each PCa member 6 (for example,). , 60 N / mm ² ) may be used. The first to third wall portions 2, 4 and 5 have concrete having different strengths in the wall thickness direction, and as a whole satisfy the strength required for the earthquake-resistant wall.

The earthquake-resistant wall and floor slab 3 on the upper floors are further constructed by the same procedure. As shown in FIG. 1, the width retaining bar 14 may be arranged at the upper ends of the wall portions 2, 4 and 5.

FIG. 8 is a cross-sectional view showing details of the configuration between the floor slab 3 and each PCa member 6 when the filler for the cast-in-place portion 7 is placed. The bolt 16 is fixed to the floor slab 3 so that its head protrudes from the upper surface of the floor slab 3. Each PCa member 6 is arranged so as to be placed on the head of the bolt 16. Therefore, a gap is formed between the lower surface of each PCa member 6 and the upper surface of the floor slab 3. A pair of root winding angles 17 and 17 are installed so as to abut the upper surface of the floor slab 3 and the outer surface of the lower portion of each PCa member 6. A separator 18 is installed between the pair of root-wrapping angles 17 and 17 to prevent the pair of root-wrapping angles 17 and 17 from moving apart from each other. When the filler is placed between the PCa members 6 and 6 facing each other, the filler wraps around in the gap between the lower surface of each PCa member 6 provided by the bolt 16 and the upper surface of the floor slab 3. Before placing the filler between the PCa members 6 and 6 facing each other, the gap provided by the bolt 16 may be filled with the filler such as grout.

The first to third wall portions 2, 4 and 5, respectively, have a half PCa structure. That is, by arranging a pair of PCa members 6 and 6 on both sides of the first to third wall portions 2, 4 and 5 in the wall thickness direction of the earthquake-resistant wall to be constructed, and placing a filler between them. Will be built. In this way, since each PCa member 6 serves as a formwork and does not require formwork construction, and because the vertical bars 11 and horizontal bars 12 do not need to be arranged at the construction site, the construction period can be shortened and the cost can be shortened. Can be suppressed.

Since both the vertical bar 11 and the horizontal bar 12 are joined by the lap joint, the workability is better and the material cost can be suppressed as compared with the case where the mechanical joint is used. Further, the lower end side of the vertical bar 11 is embedded in the ridge 10, the upper end side protrudes from the ridge 10, and the ridges 10 on the lower floor and the upper floor are laterally displaced from each other. The upper end side of the vertical streaks 11 of the lower floor to be formed and the lower end side of the vertical streaks 11 of the upper floor overlap in the horizontal direction. Therefore, as compared with the case where the vertical bars forming the lap joints are overlapped in the wall thickness direction, the empty space in the wall thickness direction of each in-situ striking portion 7 becomes wider, so that the joint bars 13 for connecting the horizontal bars 12 are arranged. It can be streaked and the workability of placing the filler for forming the in-situ casting portion 7 is improved.

Since each PCa member 6 has a ridge 10, unevenness that functions as a shear cotter is formed on the contact surface between each PCa member 6 and each in-situ striking portion 7. It should be noted that the inner surface (the surface on the side having the ridges 10) of the concrete portion 8 of each PCa member 6 is provided with irregularities of about several mm to enhance the integrity with the filler constituting each in-situ casting portion 7. Is preferable. Further, since the vertical streaks 11 are embedded in the ridges 10, it is possible to prevent the vertical streaks 11 from being separated from the PCa member 6 during transportation of the PCa member 6. Since the ridges 10 are provided along the vertical direction, there are irregularities in the lateral direction, but since there are no large irregularities in the vertical direction and air pools are unlikely to occur, a filler for the in-situ casting portion 7 is placed. Cheap.

9 and 10 show a first modification of the first embodiment. The first modification is different from the first embodiment in that the floor slab 3 is constructed after the third to sixth PCa members 6c to 6f to be located on the floor slab 3 are arranged at predetermined positions.

As shown in FIG. 9, after the first wall portion 2 is constructed, the third to sixth PCa members 6c to 6f are arranged at predetermined positions. Although not shown, the third to sixth PCa members 6c to 6f are supported by temporary materials such as a single pipe fixed to a pillar or a floor slab 3 in the lower layer. Next, as shown in FIG. 10, concrete is cast between the first wall portion 2 and the third to sixth PCa members 6c to 6f to construct the floor slab 3.

11 and 12 show a second modification of the first embodiment. The second modification is different from the first embodiment in that the upper ends of the first to third wall portions 2, 4 and 5 are located at the height of the upper surface of the floor slab 3.

The joint structure 1 according to the second modification is suitable for separating concrete between the floor slab 3 and the cast-in-place portion 7. As shown in FIG. 11, both ends of the width retaining bar 14 are placed on the upper surface of the ridge 10 of the PCa member 6 on the lower floor. Since the ridge 10 of the PCa member 6 on the upper floor is laterally displaced with respect to the ridge 10 of the PCa member 6 on the lower floor, the width retaining bar 14 is embedded in the on-site striking portion 7 on the upper floor.

FIG. 12 is a plan view in a state after the filler of the cast-in-place portion 7 is placed and before the concrete of the floor slab 3 is placed. At the time of manufacturing each PCa member 6 at the factory, a slab bar 19 extending so as to penetrate the vicinity of the upper end of the concrete portion 8 in the wall thickness direction is attached. Inside a pair of PCa members 6 and 6 facing each other, the slab bars 19 attached to the respective PCa members 6 are arranged so as to be vertically overlapped to form a lap joint. Further, in order to secure the overlapping length, the slab bar 19 extends from the recess 15 of the concrete portion 8 to the vicinity of the recess 15 of the PCa member 6 on the opposite side, and the inner end thereof forms a U shape. Is preferable. A through hole (not shown) is provided in the vicinity of the upper end of the concrete portion 8 in the wall thickness direction, and a slab bar 19 is inserted into the through hole at the construction site to form an inner peripheral surface of the through hole and the slab bar 19. Grout may be injected between.

FIG. 13 shows a third modification of the first embodiment. In the first embodiment described above, the vertical bars 11 are arranged closer to the lateral ends of the ridge 10 so that the two vertical bars 11 forming the lap joint are close to each other. In the third modification, the vertical bar 11 is arranged at the center of the ridge 10 in the lateral direction and is joined by an empty lap joint. The width retaining bar 14 shown in FIG. 13 is arranged below the second and third wall portions 2 and 5, and is embedded in the second and third in-situ striking portions 7b and 7c. Since the width retaining bar 14 engages with the outside of the two vertical bars 11 and 11 protruding from the lower floors, it is better for the vertical bars 11 to be located in the center of the ridge 10 in the lateral direction to form the PCa member 6 on the upper floors. When installed at a predetermined position, the width retaining bar 14 is likely to fit in the recess 15. In particular, the third modification is suitable when the pitch of the vertical streaks 11 is short.

FIG. 14 shows a fourth modification of the first embodiment. The horizontal bars 12 in the fourth modification are the first horizontal bars 12a embedded in the main body 9 of the concrete portion 8 of the PCa member 6 and the concrete portion 8 of the PCa member 6 arranged inside the first horizontal bars 12a. It has a second horizontal streak 12b that alternately crosses the ridge 10 and the filler of the in-situ striking portion 7 that fills the recess 15. The second horizontal bar 12b is partially embedded in the ridge 10 when the PCa member 6 is manufactured at the factory. The second horizontal bar 12b is preferably arranged so as to be close to the bottom of the recess 15, and by arranging the second horizontal bar 12b in this way, when the PCa member 6 is arranged at a predetermined position, the vertical bar 11 on the lower floor is arranged. It becomes difficult to interfere with. By providing the second horizontal bar 12b, stress is easily transmitted at the joint surface between the side surface of the ridge 10 and the in-situ striking portion 7. When the second horizontal streak 12b is provided, the first horizontal streak 12a may be omitted.

FIG. 15 shows a fifth modification of the first embodiment. The PCa member 6 in the fifth modification is configured such that the lower end portion of the vertical bar 11 projects from the side surface of the ridge 10 toward the recess 15. The lower end of the vertical bar 11 is preferably U-shaped. Due to shear friction and dowel action based on the lower end of the vertical bar 11 protruding from the ridge 10, stress is easily transmitted at the joint surface between the side surface of the ridge 10 and the in-situ striking portion 7. Further, since the lower end portion of the vertical bar 11 protrudes from the ridge 10, the protruding portion also contributes to the lap joint, and the deterioration of the workability of manufacturing the PCa member 6 can be suppressed.

Instead of or in addition to the configurations of the fourth and fifth modifications shown in FIGS. 14 and 15, this joint surface is such that stress is easily transmitted at the joint surface between the side surface of the ridge 10 and the in-situ striking portion 7. The surface may be provided with irregularities or a cotter (shear key) may be provided.

FIG. 16 shows a sixth modification of the first embodiment. In the sixth modification, the means for installing the joint bar 13 is different from that in the first embodiment. An assembly 21 having four auxiliary bars 20 arranged at four corners of a rectangle in a plan view and extending in the vertical direction and joint bars 13 supported by the four additional bars 20 is placed on the floor slab 3. By placing, the joint muscle 13 is arranged at a predetermined position. It is preferable to bind the appendages 20 to the vertical bars 11 on the lower floors. The assembly 21 may be placed on the floor slab 3 before installation of the PCa member 6 having the lateral streaks 12 (see FIG. 1) to be joined as shown in FIG. 16, or a part of the PCa member 6 or It may be placed on the floor slab 3 after all the installation.

FIG. 17 shows a seventh modification of the first embodiment. In the seventh modification, in the pair of PCa members 6 and 6 facing each other, the ridges 10 are arranged so as to be laterally displaced from each other, and the ridges 10 of one PCa member 6 are arranged so as to be laterally displaced from each other. It faces the recess 15. Therefore, the vertical streaks 11 on one PCa member 6 side and the vertical streaks 11 on the other PCa member 6 side are staggered. With such a configuration, the width retaining bar 14 cannot be arranged, but the wall thickness can be reduced.

FIG. 18 shows an example in which the floor slab 3 is constructed by the half PCa method in the first embodiment. The floor slab 3 has a half PCa floor member 22 manufactured at a factory and a site-cast floor portion 23 on which concrete is cast at a construction site. In the example shown in FIG. 18A, the beam main bar 24 and the stirrups 25 surrounding the beam main bar 24 are all arranged at the construction site, and the on-site striking portion 7 of the shear wall and the on-site striking portion 23 of the floor slab 3 are arranged. It is cast integrally with the same type of concrete. In the example shown in FIG. 18B, the lower stirrups 25a in which the PCa members 6 and 6 facing each other extend to the lower part and one side of the lower beam main bar 24 and the stirrup 25, respectively. The upper beam main bar 24 and the cap tie 25b are arranged at the construction site. After arranging the upper beam main bar 24 and the cap tie 25b, the cast-in-place portion 7 of the earthquake-resistant wall and the cast-in-place floor portion 23 of the floor slab 3 are integrally cast with the same type of concrete. In the example shown in FIG. 18C, the upper ends of the PCa members 6 and 6 facing each other are located at the height of the upper surface of the floor slab 3 (second modification), and the PCa member 6 is the beam main bar 24 and the stirrups 25. Has. The upper and lower portions of the stirrups 25 project inward from the concrete portion 8, and the stirrups 25 of the two PCa members 6 and 6 facing each other are combined to form a quadrangular frame shape.

FIG. 19 is a horizontal cross-sectional view of an earthquake-resistant wall showing an example of joining PCa members 6 and 6 laterally adjacent to each other in the first embodiment. In the example shown in FIG. 19 (A), the concrete portions 8 and 8 of the PCa members 6 and 6 adjacent to each other in the lateral direction are separated from each other, and a filler is cast integrally with the in-situ casting portion 7 between them. Will be set up. In the example shown in FIG. 19B, the concrete portions 8 and 8 of the PCa members 6 and 6 adjacent to each other in the lateral direction are separated from each other, and a grout 26 is provided between the concrete portions 8 and 8 in addition to the cast-in-place portion 7. Infused. In the examples shown in FIGS. 19C to 19E, the lateral ends of the concrete portions 8 and 8 of the two PCa members 6 and 6 are in contact with each other. In the example shown in FIG. 19C, the ends of the concrete portions 8 and 8 have the same width as the neighboring portions. In the example shown in FIG. 19D, the inside of the lateral end portion of each concrete portion 8 is chamfered. In the example shown in FIG. 19 (E), the lateral ends of the respective concrete portions 8 are formed at an acute angle so as to be brought into contact with each other on the outside. When the end portion is formed at an acute angle, the end portion may be reinforced with a steel plate or the like. If the lateral end portion of the concrete portion 8 is chamfered or formed at an acute angle, the work of attaching the two concrete portions 8 and 8 to each other becomes easier.

FIG. 20 shows an eighth modification of the first embodiment. The eighth modification is applied by rotating the PCa member 6 of the first embodiment by 90 °. In this eighth modification, the ridge 10 of the PCa member 6 extends in the lateral direction. Therefore, the reinforcing bar embedded in the ridge 10 and extending in the lateral direction becomes the horizontal bar 27, and the reinforcing bar embedded in the main body 9 and extending in the vertical direction becomes the vertical bar 28. One end side of the horizontal bar 27 protruding from the concrete portion 8 forms a lap joint with the horizontal bar 27 embedded in the ridge 10 of the PCa member adjacent to the protruding side. Further, the vertical bars 28 and 28 of the PCa members 6 and 6 that are vertically adjacent to each other are joined by the joint bars 13. Further, in joining the PCa column 29 and the earthquake-resistant wall to each other, the column lateral bar 31 is projected from the concrete portion 30 of the PCa column 29, and the protruding portion is received by the recess 15 of the PCa member 6 to receive the PCa member 6 A lap joint is formed with the horizontal bar 27 of the above.

FIG. 21 shows a case where the earthquake-resistant wall is joined to the PCa column 29 in the first embodiment. The PCa column 29 surrounds the concrete portion 30 that defines the outer shape of the column, the column main bar 32 that is embedded in the concrete portion 30 and extends in the vertical direction, and the column main bar 32 that is embedded in the concrete portion 30 and surrounds the column main bar 32. It has a strip 33 extending in the horizontal direction and a column horizontal bar 31 having one end embedded in the concrete portion 30 and extending laterally so that the other end protrudes from the concrete portion 30. The column horizontal bars 31 are arranged at the same height as the horizontal bars 12, and the other end side of the column horizontal bars 31 rushes into the second in-situ striking portion 7b, so that the horizontal bars 12 and the column horizontal bars 31 are connected by an empty lap joint. Is done. A filler 34 made of concrete or grout is placed between the second wall portion 4 and the concrete portion 30 of the PCa pillar 29. When the same type of filler as the filler for the cast-in-place portion is used as the filler 34, both may be integrally cast.

FIG. 22 shows a modified example in which the earthquake-resistant wall is joined to the PCa column 29 in the first embodiment. This modified example differs from the example shown in FIG. 21 in that the horizontal bar 12 of the second wall portion 4 is arranged at the construction site and embedded in the on-site striking portion 7. The horizontal bar 12 is arranged by hooking it on a hook (not shown) or the like attached to the PCa member 6. The horizontal bars 12 are double-arranged, and the width stop bars 35 are engaged with the two horizontal bars 12 and 12 that are aligned in the wall thickness direction. The column horizontal bars 31 and the horizontal bars 12 may be overlapped with each other in the wall thickness direction as shown in the figure, or may be overlapped with each other in the vertical direction. By burying the horizontal bar 12 in the in-situ striking portion 7, the lap joint can be formed in a state close to the column horizontal bar 31, so that stress is easily transmitted between the horizontal bar 12 and the column horizontal bar 31. In addition, the horizontal bar 12 may be embedded in the in-situ striking portion 7 other than the portion to be joined to the PCa column 29.

23 and 24 show the joint structure 41 of the half PCa shear wall according to the second embodiment. In the description, the configurations common to the first embodiment are designated by the same reference numerals by omitting the description. The joining structure 41 according to the second embodiment is different from the first embodiment in that the PCa member 42 does not have the ridge 10 (see FIG. 4).

The joint structure 41 includes a first wall portion 43 that constitutes an earthquake-resistant wall on the lower floor, a second wall portion 44 that constitutes an earthquake-resistant wall on the upper floor and is adjacent to the first wall portion 43 via the floor slab 3. It constitutes an earthquake-resistant wall on the upper floor and has a third wall portion 45 adjacent to the second wall portion 44. The first to third wall portions 43, 44, and 45 are walls having a half PCa structure, respectively.

The relative positional relationship between the first to third wall portions 43, 44, 45 is the same as that of the first embodiment, respectively, and the pair of PCa members 42a to 42f and the site filled between them are filled. It has in-situ punching portions 46a to 46c including a punching filler. The method of adding a subscript to the code of the PCa member 42 and the on-site striking portion 46 and the meaning when the subscript is omitted are the same as those in the first embodiment.

Each PCa member 42 has a concrete portion 47 formed of concrete cast in a factory, and the concrete portion 47 is substantially only a flat plate-shaped main body portion 9 having a predetermined thickness from the outer surface. Consists of. Further, each PCa member 6 has a vertical bar 11 supported by a support 48 protruding from the inner surface of the main body 9, and a horizontal bar 12 embedded in the main body 9. As the support 48, for example, a lattice muscle can be used. The vertical bar 11, the horizontal bar 12, and the support 48 are attached to the PCa member 42 when the PCa member 42 is manufactured at the factory. The filler of the cast-in-place portion 46 is the same as that of the first embodiment.

The vertical bar 11 between the first wall portion 43 and the second wall portion 44 is joined by a lap joint. The horizontal bar 12 between the second wall portion 44 and the third wall portion 45 is joined by forming an empty lap joint with the joint bar 13. Since the portions of the vertical bars 11 forming the lap joints overlap each other in the lateral direction, the installation space for the joint bars 13 can be secured.

Since both of the portions forming the joint of the vertical bar 11 are embedded in the in-situ striking portion 46, both can be brought close to each other, and the stress transmission of the joint of the vertical bar 11 can be performed without going through the joint surface. .. Therefore, stress is easily transmitted between the connected vertical bars 11 and 11.

Since there is no ridge 10, the configuration of the PCa member 42 is simplified, and the PCa member 42 can be easily manufactured.

Although the description of the specific embodiment is completed above, the present invention can be widely modified without being limited to the above embodiment. Each modification of the first embodiment can be applied to the second embodiment as long as there is no particular contradiction. In addition, the pillar may be cast on site. The upper floor walls may be joined to the lower floor walls via beams instead of floor slabs.

1,41: Half PCa earthquake-resistant wall joint structure 2,43: First wall part 3: Floor slab 4,44: Second wall part 5,45: Third wall part 6,42: PCa member 7,46: Site Strike part 8: Concrete part 9: Main body part 10: Protrusion 11: Vertical bar (first reinforcing bar)
12: Horizontal bar (second rebar)
13: Joint rebar (reinforcing bar protruding in the second direction)
14: Width retaining bar 15: Recessed 27: Horizontal bar (first reinforcing bar)
28: Vertical bar (second rebar)
29: PCa column 31: Column lateral bar (reinforcing bar protruding in the second direction)

Claims (10)

It is a joint structure of half PCa shear wall,
A first site including a first PCa member, a second PCa member arranged apart from the first PCa member in the wall thickness direction, and a cast-in-place filler filled between the first PCa member and the second PCa member. The first wall part with the striking part and
A third PCa member that is directly or indirectly adjacent to the first wall portion in the first direction along the wall surface of the half PCa shear wall and is consistent with the first PCa member in the first direction. A fourth PCa member that is arranged apart from the third PCa member in the wall thickness direction and matches the second PCa member in the first direction, and a site filled between the third PCa member and the fourth PCa member. It has a second wall portion having a second in-situ casting portion containing a casting filler, and has a second wall portion.
Each of the first to fourth PCa members is a concrete portion including a main body portion having a predetermined thickness from the outer surface, and one of vertical and horizontal bars extending in the first direction, and the main body. It has a first reinforcing bar located inside the part,
The first wall portion and the second wall portion are either one of the vertical streaks and the horizontal streaks, respectively, orthogonal to the first direction and in the second direction along the wall surface of the half PCa earthquake-resistant wall. Has an extending second rebar and
One end side of the first reinforcing bar of the first wall portion rushes into the second in-situ striking portion, and the first reinforcing bar of the second wall portion becomes the first reinforcing bar of the first wall portion. On the other hand, a joint structure characterized in that it is arranged so as to form a lap joint so as to be displaced in the second direction. The joining structure according to claim 1, wherein each of the first to fourth PCa members has the second reinforcing bar. Each of the concrete portions of the first to fourth PCa members has a plurality of ridges that bulge inward from the main body and extend along the first direction.
The first reinforcing bar is embedded in the ridge, and the first reinforcing bar is embedded in the ridge.
Claim 1 or 2 characterized in that the ridges of the third and fourth PCa members are arranged so as to be offset in the second direction with respect to the ridges of the first and second PCa members, respectively. The joint structure described in. The joining structure according to claim 3, wherein at least a part of the second reinforcing bar is arranged so as to penetrate the ridge. 3. Joint structure. The joint structure according to claim 1, wherein each of the first to fourth PCa members has a supporting reinforcing bar protruding from the concrete portion in order to support the first reinforcing bar exposed from the concrete portion. Further having a third wall or PCa column directly or indirectly adjacent to the second wall in the second direction.
Reinforcing bars protruding in the second direction from the concrete portion of the third wall portion or the PCa column plunge into the second in-situ striking portion in order to form a lap joint with the second reinforcing bar of the second wall portion. The joint structure according to any one of claims 1 to 6, wherein the joint structure is provided. The first reinforcing bar of the first PCa member and the first reinforcing bar of the second PCa member are aligned with each other in the thickness direction of the wall, and the outsides of the first reinforcing bar are engaged with each other by the width retaining bar on the one end side. The joint structure between earthquake-resistant walls according to any one of claims 1 to 7, wherein the structure is characterized by the above. The invention according to any one of claims 1 to 8, wherein the first reinforcing bar is the vertical reinforcing bar, and the second wall portion is adjacent to the first wall portion via a floor slab. Joint structure between shear walls. The joint structure according to any one of claims 1 to 8, wherein the first reinforcing bar is the vertical reinforcing bar, and the second wall portion is directly adjacent to the first wall portion.

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