JP7360772B2 - Earthquake reinforcement structure - Google Patents

Description

The present invention relates to an earthquake-resistant reinforcement structure for an existing building having a cantilevered slab.

"Slab" means the structural floor or roof between the upper and lower floor dwelling units constructed of reinforced concrete. Furthermore, the term "cantilevered slab" refers to a portion of the slab that protrudes from the exterior wall like a cantilever beam. Cantilever slabs are mainly used for communal hallways and balconies in apartment buildings.

When seismically reinforcing an existing reinforced concrete (RC) building, it is strongly desired to ensure daylight from the existing windows. Earthquake reinforcement structures that meet this demand are disclosed in Patent Documents 1 and 2, for example.

The "seismic reinforcement structure for an existing building" in Patent Document 1 has a compressive strength on the outer surface of the columns and beams located on the outside wall side of the existing building that is higher than the compressive strength of the concrete that makes up the columns and beams. A reinforcement body made of concrete is fixed.

The "reinforced structure" of Patent Document 2 includes a reinforced column part, a reinforced beam part, and a reinforced intersection part. The reinforcing column section is arranged on the exterior wall side of the existing building at a position corresponding to the column section, and is made of a hardened concrete body with reinforcing bars embedded therein. The reinforcing beam section is arranged on the exterior wall side of the existing building at a position corresponding to the beam section, and is made of a hardened concrete body with reinforcing bars embedded therein. The reinforced intersection is placed on the exterior wall side of the existing building at a position corresponding to the intersection, is connected to the ends of the reinforcing columns and the ends of the reinforcing beams, and is made of hardened polymer cement mortar with embedded reinforcing bars. Consisting of

Japanese Patent Application Publication No. 2008-50788 JP 2017-20332 Publication

In the case of the seismic reinforcement structure of Patent Document 1, it is necessary to remove the existing cantilevered slab (common hallway or balcony) and install an additional beam with approximately the same beam height (beam height) as the existing beam. As a result, the seismic performance of the existing building blocks themselves deteriorates, and noise, vibration, dust, etc. are generated that residents cannot tolerate.

On the other hand, in the case of the reinforced structure of Patent Document 2, the existing cantilevered slab can be preserved and the seismic performance of the existing frame itself can be prevented from deteriorating.
However, since hardened concrete is used for the reinforced columns and beams, and hardened polymer cement mortar is used for the reinforced intersections, it is necessary to pour concrete twice, which requires extra man-hours and costs, and a different type of concrete is used. There is a risk that the strength of the joint may be insufficient.

In addition, in the case of a mixed structure (hereinafter referred to as SRC/RC construction) where the lower layer is a steel-framed reinforced concrete structure (SRC structure) and the upper layer is a reinforced concrete structure (RC structure), the seismic performance of only the part (middle layer) where the SRC structure switches to the RC structure is often low.
However, in the case of the reinforcement structures of Patent Documents 1 and 2 mentioned above, in order to transmit the vertical axial force of the upper layer to the foundation, it is necessary to add a reinforcing structure from the upper layer to the foundation. Therefore, extra man-hours and costs are required for reinforcing the lower layer and foundation work, and noise, vibration, dust, etc. are also generated in the lower layer.

The present invention was devised to solve the above-mentioned problems. That is, a first object of the present invention is to provide an earthquake-resistance reinforcing structure that can seismically reinforce an existing building by preserving the existing cantilevered slab and avoiding double pouring of concrete. The second purpose is to seismically strengthen an existing SRC/RC building, which has low seismic performance only in the part where SRC construction is switched to RC construction (middle floor), by omitting reinforcement of the lower floors and foundation work. Our goal is to provide earthquake-resistant reinforcement structures that can be used.

According to the present invention, an earthquake-resistance reinforcing structure for an existing building includes a column and a beam located along an outer wall surface, and a cantilever slab that is cantilever-supported by the column and the beam and extends outward. There it is,
a reinforcing column portion disposed at a position corresponding to the column portion;
a reinforcing beam portion disposed at a position corresponding to the beam portion,
The reinforcing column part and the reinforcing beam part have a common overhang joint part at their intersection,
The reinforcing beam part is a wide flat beam having a rectangular cross section and a height smaller than the width, and the lower end is located above the lower end of the beam part, and is in contact with the lower surface of the cantilever slab and extends outward. extends horizontally to
The seismic reinforcement structure is provided, in which the overhang joint has a width larger than the column and has a hinge relocation structure in which a hinge is formed near the width end of the overhang joint.

According to the above configuration of the present invention, the reinforcing column part and the reinforcing beam part are provided, the reinforcing beam part is a wide flat beam, the lower end of the reinforcing beam part is located above the lower end of the beam part, and the reinforcing beam part is a cantilever slab. Since it contacts the lower surface and extends outward horizontally, the existing cantilever slab can be preserved without being removed, thereby increasing the seismic performance of the seismically reinforced structure.

Furthermore, the reinforcing column and the reinforcing beam have a common overhanging joint at their intersection, and the overhanging joint is wider than the pillar of the existing building and is located near the width end. It has a hinge relocation structure that forms a hinge part. As a result, the span length of the reinforcing beam can be made substantially shorter than that of the existing building, and the seismic performance of the seismically reinforced structure can be further improved.

Moreover, the same concrete can be used as a whole for the seismic reinforcement structure mentioned above.
Therefore, by using the hinge relocation structure, it is possible to avoid double pouring of concrete and to strengthen earthquake resistance of an existing building.

FIG. 2 is a front view of an existing building with a cantilevered slab. FIG. 1A is a view taken along the line AA in FIG. 1A. FIG. 1A is a view taken along the line BB in FIG. 1A. FIG. 1B is an enlarged view of section C in FIG. 1A. FIG. 2A is a sectional view taken along line DD in FIG. 2A. FIG. 2A is a sectional view taken along line EE in FIG. 2A. FIG. 2B is a view taken along the line FF in FIG. 2A. It is a sectional view of a vertical column part, a reinforcement beam part, and a reinforcement intermediate column. FIG. 2A is an explanatory diagram of part A in FIG. 2A. FIG. 2B is an explanatory diagram of part B in FIG. 2A. FIG. 2B is an explanatory diagram of the C section in FIG. 2A. FIG. 2B is an anchor diagram of a portion corresponding to FIG. 2A. FIG. 5A is a sectional view taken along line BB in FIG. 5A. It is an anchor diagram of columns and beams. It is a figure which shows 2nd Embodiment of a reinforcement beam part. It is a figure which shows 2nd Embodiment of a reinforcement intermediate column.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings. Note that common parts in each figure are given the same reference numerals, and redundant explanation will be omitted.

1A is a front view of the existing building 1, FIG. 1B is a view taken along the line AA in FIG. 1A, and FIG. 1C is a view taken along the line BB in FIG. 1A.
In this example, the existing building 1 is a nine-story apartment complex (for example, a condominium), and is supported cantilevered by columns 3 and beams 4 located along the outer wall surface 2. and an outwardly extending cantilevered slab 5. The cantilevered slab 5 is a common hallway or balcony.

The horizontal cross-sectional shape of the pillar portion 3 is, for example, a rectangular shape with a width of 900 mm on the outer wall surface 2 and a thickness of 650 mm. Further, the vertical cross-sectional shape of the beam portion 4 is, for example, a rectangular shape with a height of 700 mm and a thickness of 450 mm. Further, the vertical cross-sectional shape of the cantilevered slab 5 is, for example, a flat plate shape with a maximum height of 230 mm and a width in the depth direction (Y direction) of 1400 mm. Further, the cantilever slab 5 is supported in a continuous cantilever manner by the upper end portion of the beam portion 4 and the column portion 3.

Furthermore, the existing building 1 has a floor slab 6 and windows 7.
The floor slab 6 is a structural floor made of reinforced concrete and located between the upper and lower floor dwelling units. Further, the window 7 is a lighting window provided on the wall of each living room of the apartment complex.
The existing building 1 further includes an intermediate wall 8 that vertically connects a pair of vertically adjacent beam portions 4 between a pair of horizontally adjacent pillar portions 3. The intermediate wall 8 is a fixed wall independent from the column part 3.

In FIG. 1C, the horizontal direction in which five living rooms are adjacent to each other is the X direction, and the horizontal direction (depth direction) perpendicular to the X direction of each living room is the Y direction.
Further, in this figure, the wall positions X that partition five living rooms are taken as wall positions X1, X2, X3, X4, X5, and X6 in order from the left side. In this example, wall positions X1 and X6 are the outer surface positions of the wall, and wall positions X2, X3, X4, and X5 are the center positions of the wall. The interval between adjacent wall positions X (interval in the X direction) is, for example, 5 m to 7 m.
In this figure, the surface position Y of the outer wall on the front side is surface position Y1, and the surface position Y of the outer wall on the rear side is surface position Y2. Note that the front and back sides of the existing building 1 may be reversed.

In FIGS. 1A and 1B, the existing building 1 is an SRC/RC structure in which the lower layer is an SRC structure and the upper layer is an RC structure. In this example, the lower floors are from the 1st floor to the 5th floor (between 5FL and 6FL), and in this example, the lower floors are from the 5th floor (between 5FL and 6FL) to the roof. Note that FL means the floor position.
Further, in FIGS. 1A and 1B, the lower layer has a steel frame 9 that constitutes an SRC structure. The steel frame 9 includes a column steel frame 9a that is buried in the column part 3 and extends vertically to the lower end of the upper layer, and a beam steel frame 9b that is buried in the beam part 4 and has both ends fixed to the column steel frame 9a. The steel frame 9 is, for example, an H-shaped steel.

In addition, in the present invention, the existing building 1 is not limited to SRC/RC construction, but may be entirely RC construction or SRC construction.

In FIGS. 1A to 1C, an earthquake reinforcement structure 100 according to the present invention is provided on the front side of an existing building 1. In addition, the seismic reinforcement structure 100 is not limited to the front side, and may be on the back side or both.
In this example, the seismic reinforcement structure 100 is an area between the fourth floor floor (4FL) and the seventh floor floor (7FL) of the existing building 1, including the partition wall from wall position X2 to wall position X5. It is set in.
In addition, this structure corresponds to the fact that only the part (middle layer) of the SRC/RC structure where the SRC structure switches to the RC structure has low earthquake resistance. However, it may be applied to places where the seismic performance of RC structures is low.
Therefore, the installation range of the seismic reinforcement structure 100 is not limited to this example, and can be freely set according to the seismic performance of the existing building 1. For example, the seismic reinforcement structure 100 may be provided in a range from wall position X1 to wall position X6.

2A is an enlarged view of section C in FIG. 1A, FIG. 2B is a sectional view taken along line DD in FIG. 2A, FIG. 2C is a sectional view taken along line EE in FIG. 2A, and FIG. 2D is a view taken along line FF in FIG. 2A.
In FIGS. 2A to 2D, the seismic reinforcement structure 100 includes a reinforcement column part 10 and a reinforcement beam part 20.
Further, the reinforcing column part 10 and the reinforcing beam part 20 have a shared overhang joint part 14 at the intersection thereof.

The reinforcing column portion 10 is arranged at a position corresponding to the column portion 3 of the existing building 1. The reinforcing column portion 10 has a vertical column portion 12 and an overhang joint portion 14 that are integrally formed as a whole.
The vertical column part 12 has the same width in the X direction as the column part 3 of the existing building 1, and extends vertically. The overhang joint part 14 has a width in the X direction larger than the column part 3 and the vertical column part 12 of the existing building 1, and has a hinge relocation structure in which a hinge part H is formed near the width end. Details of the hinge relocation structure will be described later.

The reinforcing beam portion 20 is arranged at a position corresponding to the beam portion 4 of the existing building 1. The reinforcing beam section 20 has a horizontal beam section 22 and an overhang joint section 14 that are integrally formed as a whole. Note that, as described above, the reinforcing column portion 10 shares the overhang joint portion 14.
Both ends of the horizontal beam portion 22 in the X direction are connected to the overhang joint portion 14 . Further, as shown in FIG. 2B, the lower end 20a of the reinforcing beam portion 20 is located above the lower end 4a of the beam portion 4 of the existing building 1. Further, the reinforcing beam portion 20 is in contact with the lower surface 5a of the cantilevered slab 5 and extends horizontally to the outside of the vertical column portion 12. The outer end of the reinforcing beam portion 20 is preferably located inside the outer end of the cantilever slab 5. In this example, the reinforcing beam portion 20 is a wide flat beam that has a rectangular cross section and whose height is smaller than its width.
Further, as will be described later, since the reinforcing beam portion 20 is integrated with the beam portion 4 of the existing building 1 via the buried anchor 46, the rigidity of the beam of the seismic reinforcement structure 100 can be significantly increased.

In FIG. 2A, the overhang joint 14 is located at the same height as the horizontal beam 22. In FIG.
Further, as shown in FIG. 2D, the vertical column portion 12 of the reinforcing column portion 10 is provided to vertically penetrate the cantilever slab 5. Furthermore, a horizontal gap C1 is provided between the vertical column portion 12 and the cantilever slab 5. The gap C1 is preferably set so that horizontal force is not transmitted to the cantilever slab 5 even if the vertical column portion 12 is displaced during an earthquake. The gap C1 is, for example, 10 to 20 mm.
Further, as will be described later, since the vertical column portion 12 is integrated with the column portion 3 of the existing building 1 via the buried anchor 46, the rigidity of the column of the seismic reinforcement structure 100 can be significantly increased.

In FIGS. 2A to 2D, the seismic reinforcement structure 100 further includes a reinforcement intermediate column 30. The reinforcing intermediate column 30 is arranged at a position corresponding to the intermediate wall 8 and has a width approximately equal to the entire width of the intermediate wall 8. Further, the reinforcing intermediate column 30 is connected to a plurality of vertically adjacent reinforcing beam parts 20.
Moreover, as shown in FIG. 2D, the reinforcing intermediate column 30 is provided to vertically penetrate the cantilever slab 5. Furthermore, a horizontal gap C2 is provided between the reinforcing intermediate column 30 and the cantilever slab 5. The gap C2 is preferably set so that horizontal force is not transmitted to the cantilever slab 5 even if the reinforcing intermediate column 30 is displaced during an earthquake. The gap C2 is, for example, 10 to 20 mm.

With the above-described configuration of the reinforcing intermediate pillar 30, the existing window 7 is not blocked from light by the reinforcing intermediate pillar 30, so that sufficient light shielding from the existing window 7 can be ensured.
Moreover, since the reinforcing intermediate column 30 is connected to the plurality of vertically adjacent reinforcing beam parts 20, the rigidity of the beam of the seismic reinforcement structure 100 can be further increased.
Note that the reinforcing intermediate column 30 is not essential, and may be omitted as long as the beam rigidity of the seismic reinforcement structure 100 is ensured.

FIG. 3 is a cross-sectional view of the vertical column portion 12, the horizontal beam portion 22, and the reinforcing intermediate column 30. In this figure, (a) and (c) are partially enlarged views of FIG. 2D, and (b) are partially enlarged views of FIG. 2B.

In FIG. 3A, the width w1 of the vertical column portion 12 is set to be approximately the same as the width of the column portion 3. In FIG. For example, when the width of the column 3 (width at the outer wall surface 2) is 900 mm, the width of the vertical column 12 is preferably 900 mm.
Further, the thickness b1 of the vertical column portion 12 is set to be approximately equal to or less than the thickness of the column portion 3. For example, when the thickness of the column 3 is 650 mm, the thickness of the vertical column 12 is preferably 550 to 600 mm.
Further, the vertical column portion 12 includes a column main reinforcement 41a extending in the axial direction therein, and an annular reinforcing bar 42a extending annularly surrounding the column main reinforcement 41a in the cross section.

In FIG. 3(b), the height h1 of the reinforcing beam portion 20 is set to be equal to or less than the height from the lower surface 5a of the cantilever slab 5 to the lower end 4a of the beam portion 4. For example, when the height of the beam portion 4 is 700 mm and the maximum height of the cantilever slab 5 is 230 mm, the height h1 of the reinforcing beam portion 20 is preferably 450 to 470 mm.
Further, the horizontal beam portion 22 includes a main beam reinforcement 41b extending in the axial direction therein, and an annular reinforcing bar 42b extending annularly surrounding the main beam reinforcement 41b in the cross section.

In FIG. 3(c), the width w2 of the reinforcing intermediate column 30 is set to be approximately the same as the width of the intermediate wall 8. In FIG. For example, when the width of the intermediate wall 8 is 800 mm, the width w2 of the reinforcing intermediate column 30 is preferably 800 mm.
Further, the thickness b2 of the reinforcing intermediate column 30 is preferably set to be approximately the same as the thickness b1 of the vertical column portion 12. For example, when the thickness b1 of the vertical column portion 12 is 550 mm, the thickness b2 of the reinforcing intermediate column 30 is preferably 550 mm.
Further, the reinforcing intermediate column 30 includes a stud main reinforcement 41c that extends in the axial direction therein, and an annular reinforcing bar 42c that extends annularly surrounding the stud main reinforcement 41c in the cross section.

Moreover, concrete having a higher compressive strength than the concrete of the existing building 1 is used for the concrete forming the vertical column part 12, the horizontal beam part 22, and the reinforcing intermediate column 30.
With the above-described configuration, the vertical column part 12, horizontal beam part 22, and reinforced intermediate column 30 are set to have sufficient strength against compression, tension, bending, shear, and torsion that occur in each part under a predetermined earthquake load. ing.

4A is an explanatory diagram of part A in FIG. 2A, FIG. 4B is an explanatory diagram of part B in FIG. 2A, and FIG. 4C is an explanatory diagram of part C in FIG. 2A.

4A, (a) is an enlarged view of part A in FIG. 2A, and (b) is a sectional view taken along line BB in (a).
In this figure, the overhang joint 14 has a vertical cross section corresponding to the end of the horizontal beam 22. Further, the reinforcing bars (beam main reinforcement 41b and annular reinforcing bar 42b, not shown) of the reinforcing beam portion 20 shown in FIG. 3(b) are similarly arranged in the overhang joint portion 14.
Further, the overhang joint portion 14 has a horizontal cross section wider than the end portion of the vertical column portion 12. In addition, the reinforcing bars (column main reinforcement 41a and annular reinforcing bar 42a) of the vertical column 12 shown in FIG. (not shown) are similarly reinforced.
Due to the above-described configuration, the overhang joint portion 14 is set to have higher strength than the horizontal beam portion 22 and the vertical column portion 12 against compression, tension, bending, shearing, and torsion.

In FIG. 4A, the hinge relocation structure has reinforcing bars 44 that are embedded in the overhanging joint 14 and form a hinge H near the width end thereof (near the connection with the horizontal beam 22). The reinforcing bars 44 are, for example, bending reinforcing bars 44a, U-shaped reinforcing bars 44b, cap bars 44c, or restraint bars 44d.
The hinge portion H is formed at the position indicated by △ in the figure. The horizontal position of the hinge H from the right side of the vertical column 12 is preferably shorter than the width w1 of the vertical column 12, and when the width w1 of the vertical column 12 is 900 mm, it is preferably 400 to 500 mm. is 450mm.
With the above configuration, the rigidity of the overhang joint 14 can be increased, the span length of the reinforcing beam section 20 can be made shorter than that of the beam section 4 of the existing building 1, and the seismic performance of the seismic reinforcement structure 100 can be improved.

In FIG. 4B, (a) is an enlarged view of section B in FIG. 2A, and (b) is a sectional view taken along line BB in (a).
In this figure, the overhang joint 14 has a vertical cross section corresponding to the end of the horizontal beam 22. Furthermore, reinforcing bars (beam main bars 41b and annular reinforcing bars 42b, not shown) of the horizontal beam part 22 shown in FIG. 3(b) are similarly arranged in the overhang joint part 14.
Further, the overhang joint portion 14 has a horizontal cross section wider than the end portion of the vertical column portion 12. In addition, the vertical portion 14a corresponding to the vertical column portion 12 of the overhanging joint portion 14 includes reinforcing bars (column main reinforcement 41a and annular reinforcing bar 42a, not shown) of the vertical column portion 12 shown in FIG. 3(a). ) are similarly reinforced.
Due to the above-described configuration, the overhang joint portion 14 is set to have higher strength than the reinforcing beam portion 20 and the vertical column portion 12 against compression, tension, bending, shearing, and torsion. This configuration is similar to FIG. 4A.

In FIG. 4B, the hinge relocation structure includes reinforcing bars 44 that are embedded in the overhanging joint 14 and form a hinge H near the connection with the horizontal beam 22. The reinforcing bars 44 include, for example, bending reinforcing bars 44a, U-shaped reinforcing bars 44b, and restraint bars 44d.
The position of the hinge portion H is preferably shorter than the width w1 of the vertical portion equivalent portion 14a from the left and right side surfaces in the diagram of the vertical portion equivalent portion 14a, and when the width w1 of the vertical column portion 12 is 900 mm, the position is 400 to 500 mm, Preferably it is 450 mm.
With the above configuration, the rigidity of the overhang joint 14 can be increased, the span length of the reinforcing beam section 20 can be made shorter than that of the beam section 4 of the existing building 1, and the seismic performance of the seismic reinforcement structure 100 can be improved.

In FIG. 4A, the horizontal beam portion 22 is connected only to one side (the right side in FIG. 2A) of the overhang joint portion 14. In FIGS. 1A and 2A, the configuration of the other portion where the horizontal beam portion 22 is connected to only one side of the overhanging joint portion 14 is the same as the configuration of FIG. 4A described above.
In FIG. 4B, horizontal beams 22 are connected to both sides of the overhang joint 14. In FIG. In FIGS. 1A and 2A, the configuration of the other portions where the horizontal beam portions 22 are connected to both sides of the overhang joint portion 14 is the same as the configuration of FIG. 4B described above.

In FIG. 4C, (a) is an enlarged view of section C in FIG. 2A, and (b) is a sectional view taken along line BB in (a).
In this figure, reinforcing bars shown in FIGS. 3(b) and 3(c) are similarly arranged in the horizontal beam portion 22 and the reinforcing intermediate column 30.
Further, U-shaped reinforcing bars 44b and restraint bars 44d are arranged at the connecting portion between the horizontal beam portion 22 and the reinforcing intermediate column 30 so as to connect the two.
In FIGS. 1A and 2A, the configuration of other parts where the horizontal beam portion 22 and the reinforcing intermediate column 30 are connected is the same as the configuration of FIG. 4C described above.
With the above-described configuration, the end portion of the reinforcing intermediate column 30 can be firmly connected to the intermediate portion of the horizontal beam portion 22.

5A is an anchor diagram of a portion corresponding to FIG. 2A, and FIG. 5B is a sectional view taken along line BB in FIG. 5A.
Also, Figure 6 is an anchor diagram of columns and beams, (a) is an anchor diagram of 6FL beams, (b) is an anchor diagram of 5FL columns and beams, and (c) is an anchor diagram of 4FL columns. .

In FIGS. 5A, 5B, and 6, the reinforcing column part 10 and the horizontal beam part 22 above 5FL each have a buried anchor 46 that extends horizontally and has one end buried in the column part 3 and the beam part 4, respectively.
The buried anchor 46 is a post-installed anchor in this example. Further, the buried anchor 46 is a tension anchor 46a, a shearing anchor 46b, a variable axial force anchor 46c, or a drop-off prevention anchor 46d.
The above-mentioned buried anchor 46 firmly connects and integrates the reinforcing column part 10 and the column part 3, and the horizontal beam part 22 and the beam part 4 above 5FL, thereby improving the seismic performance of the seismic reinforcement structure 100. be able to.

In FIGS. 5A and 6(a), the reinforcing intermediate column 30 has a fall prevention anchor 47 whose one end is buried in the intermediate wall 8 and extends horizontally.
With this configuration, the reinforcing intermediate column 30 and the intermediate wall 8 are firmly connected and integrated, and the seismic performance of the seismic reinforcement structure 100 can be further improved.

In FIGS. 5A and 6(c), the reinforcing column portion 10 has a welding anchor 48 at its lower end, one end of which is welded to the steel frame 9 and extends horizontally. In this example, the lower end portion of the reinforcing column portion 10 is a vertical column portion 12, and a welding anchor 48 is provided on this vertical column portion 12 and an overhang joint portion 14 above it (5FL).
With this configuration, the axial force acting on the reinforcing column part 10 of the seismic reinforcement structure 100 can be transmitted to the steel frame 9 on the lower floor, and seismic reinforcement can be performed without reinforcement and foundation work of the lower floor.

In FIG. 5A, the range surrounded by a broken line indicates the same type of buried anchor 46, drop-off prevention anchor 47, or welded anchor 48.

The seismic reinforcement structure 100 described above is preferably made of concrete having a higher compressive strength than that of the existing building 1, and is formed by one-shot pouring without pouring.

FIG. 7 is a diagram showing a second embodiment of the reinforcing beam portion 20. As shown in FIG. In this figure, (a) is a plan view of the reinforcing beam portion 20, and (b) is a sectional view taken along line BB in (a).
In this example, the beam portion 4 of the existing building 1 has a first through hole 4b that horizontally penetrates the beam portion 4 between a pair of adjacent pillar portions 3. An exhaust sleeve (not shown) having an outer diameter of 150 mm, for example, is buried in the first through hole 4b, and is configured to discharge exhaust gas from the room (for example, the kitchen) to the outside.

In FIG. 7, the above-mentioned reinforcing intermediate column 30 is not provided, and the reinforcing beam portion 20 has a missing portion 24 in the horizontal beam portion 22 at a position facing the first through hole 4b, which communicates the first through hole 4b with the outside. have
In this example, the missing portion 24 is a rectangular notch (300 mm×300 mm in plan view in this example) provided on the side surface of the horizontal beam portion 22. The cutout portion 24 is provided to penetrate from the upper surface to the lower surface of the horizontal beam portion 22, and exhaust gas is smoothly discharged to the outside (below the horizontal beam portion 22) through the cutout portion 24 from the first through hole 4b. ing.
The other configurations are similar to the reinforcing beam portion 20 of FIGS. 1 to 6.

FIG. 8 is a diagram showing a second embodiment of the reinforcing intermediate column 30. In this figure, (a) is a front view of the reinforcing intermediate column 30 corresponding to the partially enlarged view of FIG. 2A. Moreover, (b) is a BB arrow view of (a).
In this figure, the intermediate wall 8 of the existing building 1 has a second through hole 8a (not shown) that penetrates the intermediate wall 8 horizontally. The second through hole 8a is, for example, a ventilation hole that communicates the interior and exterior, or a piping hole (equipment opening) for passing piping of air conditioning equipment. Although two second through holes 8a are provided in this example, there may be one or three or more second through holes.

In FIG. 8, the reinforcing intermediate pillar 30 has a reinforcing intermediate pillar through hole (hereinafter referred to as "reinforcing through hole 32") that communicates the second through hole 8a with the outside at a position aligned with the second through hole 8a. have It is preferable that the diameter of the reinforcing through hole 32 is equal to or larger than that of the second through hole 8a.
In this example, the reinforcing through holes 32 are two circular holes provided in the reinforcing intermediate column 30. The diameter of the reinforcing through hole 32 is, for example, 50 to 150 mm.

As shown in this figure, it is preferable that a plurality of U-shaped reinforcing bars 44b be embedded around the reinforcing through hole 32 to reinforce the reinforcing through hole 32.

According to the embodiment of the present invention described above, the reinforcing column part 10 and the reinforcing beam part 20 are provided, and the reinforcing beam part 20 is a wide flat beam, and the reinforcing beam part 20 is in contact with the lower surface 5a of the cantilever slab 5 and extends outward. Since it extends horizontally in both directions, the existing cantilever slab 5 can be preserved without being removed, and the seismic performance of the seismic reinforcement structure can be improved.

In addition, since the vertical column portion 12 of the reinforcing column portion 10 is smaller in width than the column portion 3 of the existing building 1, and the lower end 20a of the reinforcing beam portion 20 is located above the lower end 4a of the beam portion 4 of the existing building 1, It is possible to secure sufficient lighting from the window 7.

Furthermore, the reinforcing column part 10 and the reinforcing beam part 20 have an overhang joint part 14 shared with each other at the intersection thereof, and the overhang joint part 14 is wider than the pillar part 3 of the existing building 1, It has a hinge relocation structure that forms a hinge portion H near its width end. With this configuration, the span length of the reinforcing beam portion 20 can be made shorter than that of the beam portion 4 of the existing building 1, and the seismic performance of the seismic reinforcement structure 100 can be further improved.

Furthermore, the above-described seismic reinforcement structure 100 can use the same concrete as a whole. That is, the seismic reinforcement structure 100 is preferably made of concrete having a higher compressive strength than the existing building 1, and is formed by one-shot pouring without pouring.
Therefore, by using the hinge relocation structure, it is possible to avoid double pouring of concrete and to strengthen the existing building 1 against earthquakes.

In addition, even if the existing building 1 is an SRC/RC structure with low seismic performance only in the part (middle layer) where the SRC structure is switched to the RC structure, the axial force acting on the reinforcing columns 10 of the seismic reinforcement structure 100 can be reduced from the lower layer. It can be transmitted to the steel frame 9 of the floor. This allows for seismic reinforcement without requiring reinforcement of the lower layer and foundation work.

The scope of the present invention is not limited to the embodiments described above, but is indicated by the claims, and includes all changes within the meaning and range equivalent to the claims.

X, X1, X2, X3, X4, X5, X6 wall position, Y, Y1, Y2 surface position,
C1, C2 Gap, H Hinge, 1 Existing building, 2 Exterior wall, 3 Column,
4 beam part, 4a lower end, 4b first through hole, 5 cantilever slab, 5a lower surface,
6 floor slab, 7 window, 8 intermediate wall, 8a second through hole,
9 Steel frame, 9a Column steel frame, 9b Beam steel frame,
10 reinforcing column part, 12 vertical column part, 14 overhanging joint part, 14a vertical part equivalent part,
20 reinforcement beam part, 20a lower end, 22 horizontal beam part, 24 missing part,
30 Reinforcement intermediate column, 32 Reinforcement through hole,
41a, 41b, 41c main reinforcement, 42a, 42b, 42c circular reinforcement,
44 reinforcing bars, 44a bending reinforcing bars, 44b U-shaped reinforcing bars, 44c cap bars,
44d restraint bar, 46 buried anchor, 46a tension anchor,
46b shear anchor, 46c variable axial force anchor,
46d, 47 Fall prevention anchor, 48 Welding anchor,
100 Earthquake-resistant reinforcement structure

Claims (11)

An earthquake-resistant reinforcement structure for an existing building, comprising a column and a beam located along an outer wall surface, and a cantilevered slab extending outward and supported by the column and the beam,
a reinforcing column portion disposed at a position corresponding to the column portion;
a reinforcing beam portion disposed at a position corresponding to the beam portion,
The reinforcing column part and the reinforcing beam part have a common overhang joint part at their intersection,
The reinforcing beam part is a wide flat beam having a rectangular cross section and a height smaller than the width, and the lower end is located above the lower end of the beam part, and is in contact with the lower surface of the cantilever slab and extends outward. extends horizontally to
The above-mentioned overhang joint part has a width larger than the above-mentioned pillar part, and has a hinge relocation structure in which a hinge part is formed near the width end of the seismic reinforcement structure. The seismic reinforcement structure according to claim 1, wherein the hinge relocation structure has reinforcing bars embedded in the overhang joint and forming the hinge near the width end. The seismic reinforcement structure according to claim 1, wherein the reinforcing column portion is provided to vertically penetrate the cantilever slab, and has a horizontal gap between the reinforcing column and the cantilever slab. The beam portion has a first through hole that horizontally penetrates the beam portion between a pair of adjacent pillar portions,
The seismic reinforcement structure according to claim 1, wherein the reinforcing beam portion has a defective portion at a position facing the first through hole that communicates the first through hole with the outside. The seismic reinforcement structure according to claim 1, wherein the reinforcing column part and the reinforcing beam part each have a buried anchor having one end buried in the column part and the beam part and extending horizontally. The existing building has an intermediate wall vertically connecting the adjacent pair of beam portions between the adjacent pair of pillar portions,
Claim 1, further comprising: a reinforcing intermediate column arranged at a position corresponding to the intermediate wall and having a width comparable to the full width of the intermediate wall, the reinforcing intermediate column being connected to a plurality of adjacent reinforcing beam sections. Earthquake reinforcement structure described in . The intermediate wall has a second through hole that horizontally penetrates the intermediate wall,
7. The seismic reinforcement structure according to claim 6, wherein the reinforcing intermediate column has a reinforcing intermediate column through hole that communicates the second through hole with the outside at a position aligned with the second through hole. 7. The seismic reinforcement structure according to claim 6, wherein the reinforcing intermediate column has a fall prevention anchor that has one end embedded in the intermediate wall and extends horizontally. 2. The seismic reinforcement structure according to claim 1, which is made of concrete having a higher compressive strength than existing buildings and is formed by one-shot pouring without pouring joints. The existing building is an SRC/RC structure in which the lower layer is SRC structure and the upper layer is RC structure,
The lower layer has a steel frame that is embedded in the column and extends vertically to the lower end of the upper layer,
2. The seismic reinforcement structure according to claim 1, wherein the reinforcing column part has a welding anchor at a lower end thereof, one end of which is welded to the steel frame and extends horizontally. The seismic reinforcement structure according to claim 1, wherein the existing building is entirely constructed of RC.

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