JP4182855B2 - Seismic wall and its reinforcement method - Google Patents

Description

  The present invention relates to a seismic wall that bears a load in a structure and a method for reinforcing the same.

  Conventionally, in order to increase the strength of structures against earthquakes, reinforcement methods have been adopted in which a seismic wall is added or the thickness of the seismic wall is increased. However, these reinforcement methods require various constructions such as rebar construction, formwork, concrete placement, etc., which is very time consuming, labor intensive and costly, and increases the cost. There were also problems such as the restriction of ease of use and the area that can be used effectively within the structure by the increase in the thickness of the seismic wall. In addition, in the case of existing earthquake-resistant walls, it is necessary to perform shearing work and hole formation work on columns or beams, and noise and dust may be generated during these operations, which may adversely affect the surrounding environment. was there. Moreover, when performing these operations, welding may be necessary, and in that case, safety measures against fire are also necessary.

In view of this, various reinforcing methods have been proposed in the past that do not depend on the addition or increase of the thickness of the shear wall. For example, a method has been proposed in which a sheet formed of fiber reinforced resin (FRP: Fiber Reinforced Plastics) is attached to a wall surface of a seismic wall for reinforcement (for example, see Patent Documents 1 and 2).
Japanese Patent Laid-Open No. 10-25904 JP-A-11-62269

  However, in such a reinforcing method using a fiber reinforced resin sheet, since the fiber reinforced resin sheet is bonded to a concrete structure, the surface treatment of the concrete surface, primer application, resin for impregnation, and winding of carbon fiber are performed. Further, there is a problem that a process such as resin overcoating is required, which requires a lot of time and labor. There is also a problem that skill is required for construction so that wrinkles and bubbles do not enter the fiber reinforced resin sheet.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a seismic wall and a method of reinforcing the seismic wall that can easily increase the proof stress without much time and cost. .

The main invention for achieving the above object is characterized in that a plurality of strip-shaped reinforcing plates are attached to both sides or one side with a space in the vertical direction so that the longitudinal direction thereof is a lateral direction. It is a seismic wall.

In such a seismic wall, the reinforcing plate may be formed of a steel plate. Alternatively, the reinforcing plate may be formed of a fiber reinforced resin including reinforcing fibers extending in the longitudinal direction.

  Further, such a seismic wall may have an opening.

  Further, in such a seismic wall, the reinforcing plate may be formed in an L-shaped cross section and disposed from the wall surface of the seismic wall along the inner peripheral surface of the opening.

Further, the method for reinforcing a seismic wall according to the present invention is to attach a plurality of strip-shaped reinforcing plates on both sides or one side of the seismic wall with an interval in the vertical direction so that their longitudinal directions are in the horizontal direction. It is characterized by.

  According to the present invention, the proof stress can be easily increased without much time and cost.

  The best mode for carrying out the shear wall and the reinforcing method thereof according to the present invention will be described below.

  1 to 3 show an embodiment of a seismic wall according to the present invention. 1 is a front view of the seismic wall, FIG. 2 is a cross-sectional view taken along the line AA ′ in FIG. 1, and FIG. 3 shows the internal reinforcing bar structure of the seismic wall. FIG.

  As shown in FIG. 1, the seismic wall 2 according to the present embodiment is installed in a frame surface composed of a concrete column portion 4 and a concrete beam portion 6.

  The seismic wall 2 is constructed of a reinforced concrete structure, and as shown in FIGS. 2 and 3, a plurality of vertical bars 8 and horizontal bars 10 are arranged in a lattice pattern. Here, the end of each horizontal bar 10 extends to the left and right concrete column parts 4 and is led out and embedded inside the column main bar 12 arranged inside the concrete column part 4. ing. Further, the end portions of the vertical bars 8 are respectively extended to the upper and lower concrete beam portions 6 and embedded in the concrete beam portions 6. In this way, the earthquake resistant wall 2 is constructed integrally with the concrete column portion 4 and the concrete beam portion 6.

  An opening 14 is provided at the center of the earthquake resistant wall 2. As shown in FIG. 2, the opening 14 is formed by penetrating the seismic wall 2 from the front and back. In the present embodiment, the opening 14 should be used as a window part of a building or a door installation part in renewal work. Shall be formed. When an opening is provided from the beginning of construction, an opening reinforcing bar can be used to reinforce the periphery of the opening. However, when an opening is provided during renewal, such an opening reinforcing bar cannot be used for reinforcement. Therefore, in the present embodiment, as described below, the reinforcing plate 20 is attached to the surface of the earthquake resistant wall 2 to reinforce the earthquake resistant wall 2 provided with the opening 14.

  That is, as shown in FIGS. 1 and 2, the reinforcing plate 20 is disposed on the wall surface of the earthquake resistant wall 2. The reinforcing plate 20 is a reinforcing member arranged to reinforce the earthquake-resistant wall 2, and is adhered to the wall surface portion of the earthquake-resistant wall 2 with an adhesive, and stress is applied to the earthquake-resistant wall 2 by an external force applied from the outside. It is generated and resists the external force applied to the seismic wall 2. The reinforcing plate 20 is formed as a strip-shaped plate material having a predetermined thickness, and is arranged in parallel along the wall surface portion of the earthquake resistant wall 2 with a space in the vertical direction.

  The reinforcing plate 20 is made of carbon fiber reinforced resin (CFRP). The carbon fiber reinforced resin is a resin having carbon fibers therein, and the carbon fibers are embedded so as to extend along the longitudinal direction of the reinforcing plate 20. This carbon fiber reinforced resin has a very high strength, particularly a tensile strength, and is very lightweight and is excellent as a material for a reinforcing material. The fiber reinforced resin (FRP) according to the present invention is not limited to the carbon fiber reinforced resin (CFRP) provided with such a carbon fiber, but other than the carbon fiber, an aramid fiber, a glass fiber, etc. Such resins may be provided with various high-strength fibers.

  Each reinforcing plate 20 is integrally joined to the wall surface portion of the earthquake resistant wall 2 by a bonding material such as an adhesive. Each reinforcing plate 20 is provided with fixing members 22 for fixing the reinforcing plate 20 to the wall surface portion of the earthquake-resistant wall 2 at both ends thereof. The fixing member 22 is formed in a plate shape, and a reinforcing plate 20 is sandwiched between the fixing member 22 and the wall surface portion of the earthquake resistant wall 2 to fix the reinforcing plate 20 to the wall surface portion of the earthquake resistant wall 2. Each fixing member 22 is fixed to the wall surface portion of the earthquake resistant wall 2 via bolts 24.

  In addition, it is preferable to set suitably the width dimension and installation space | interval of the reinforcement board 20 according to the reinforcement intensity | strength required with respect to the earthquake resistant wall 2. FIG. In the present embodiment, as described above, the reinforcing plates 20 are provided at intervals, so that the amount of the reinforcing plates 20 used can be reduced as compared with the case where the reinforcing plates 20 are attached to the entire surface, thereby reducing costs. Can be achieved.

  As described above, in the seismic wall 2 according to the present embodiment, since the reinforcing plate 20 is attached to the wall surface portion, even if an external force is applied to the seismic wall 2 due to an earthquake or the like, the reinforcing plate is caused by the external force. Since stress is also generated at 20 and the reinforcing plate 20 resists, the strength of the seismic wall 2 can be increased.

  In addition, the reinforcing plate 20 is formed in a plate shape instead of a sheet shape as in the prior art, so that the process is more rigorous than in the past, specifically, ground treatment or primer application to the concrete surface, It can be applied easily without the need for steps such as application of the impregnating resin, winding of carbon fiber, and overcoating of the resin. Thereby, compared with the past, time can be shortened, labor and labor can be reduced, and cost can be reduced.

  Moreover, since the material which is thin, light and high intensity | strength is used like the reinforcement board 20, the area which can be utilized effectively inside a structure does not reduce.

  Next, FIG. 4 and FIG. 5 show other embodiments of the reinforcing plate. FIG. 4 is a perspective view showing the reinforcing plate 30, and FIG. 5 is a diagram for explaining an arrangement example of the reinforcing plate 30. The reinforcing plate 30 is made of carbon fiber reinforced resin (CFRP), and is formed into an L-shaped cross section including a long side portion 30b and a short side portion 30c by being bent at the bent portion 30a.

  As shown in FIG. 5, the reinforcing plate 30 can be suitably disposed on the edge 2 a of the opening 14 provided in the earthquake resistant wall 2. That is, since the reinforcing plate 30 is formed in an L-shaped cross section, as shown in the figure, the reinforcing plate 30 is disposed at a right angle from the two wall surfaces of the earthquake resistant wall to the inner surface of the opening 14. Can do. Here, the reinforcing plates 30 are respectively disposed on the front and back sides of the seismic wall 2, the long side portions 30 b of each reinforcing plate 30 are disposed on the wall surface side of the seismic wall 2, and the short side portions 30 c of each reinforcing plate 30 are It is arranged on the inner surface side of the opening 14. The short side portions 30c of these two reinforcing plates 30 are overlapped and joined to each other on the inner surface portion of the opening portion 14. By using the reinforcing plate 30 that is bent and formed into an L-shaped cross section in this way, it is possible to easily reinforce the edge portion of the opening portion 14 formed in the earthquake-resistant wall 2.

  FIGS. 6-8 demonstrates the test done in order to confirm the reinforcement effect of the earthquake-resistant wall which concerns on this embodiment. FIG. 6 is a diagram showing the seismic walls constructed in this test, and FIGS. 7 and 8 are graphs showing the test results.

  In this test, three types of seismic walls as shown in FIGS. Here, a solid earthquake-resistant wall (Comparative Example 1) not provided with an opening shown in FIG. 6 (a), and a earthquake-resistant wall (Comparative Example 2) provided with an opening 14 shown in FIG. 6 (b), 6 (c) and the seismic wall (the seismic wall shown in FIGS. 1 to 3: the present invention example) in which the opening 14 shown in FIG. .

  FIG. 7 is a graph showing the relationship between the load and the member angle when a load is actually applied to each seismic wall shown in FIGS. As shown in the figure, in the example of the present invention, excellent deformation performance was exhibited even in the region exceeding the vicinity of the member angle “0.004” reaching the proof stress in the comparative example 2, and the proof stress was significantly higher than that in the comparative example 2. It can be seen that yield strength characteristics comparable to those of Comparative Example 1 (when no opening is provided) are obtained. Thus, according to the example of the present invention, the proof stress and deformation performance of the earthquake-resistant wall 2 provided with the opening 14 can be improved.

  FIG. 8 shows the relationship between the member angle and the crack width. FIG. 8A shows the test result of Comparative Example 2, and FIG. 8B shows the test result of the present invention example. Here, two measurement points, “Clip 1” and “Clip 2” are set, and the relationship between the member angle and the crack width is shown for each measurement point. Comparing FIG. 8A and FIG. 8B, it is confirmed that the width of the crack generated with the variation of the member angle is smaller in the example of the present invention than in the comparative example 2. That is, it can be seen that the width of the generated crack is smaller in the example of the present invention than in the comparative example 2, the expansion of the crack can be prevented, and the deformation of the earthquake resistant wall can be suppressed.

  In the embodiment described above, the plates formed of carbon fiber reinforced resin (CFRP) are used as the reinforcing plates 20 and 30, but the reinforcing plate 20 according to the present invention is not limited to this, for example, A plate formed of various high-strength materials such as steel may be used.

  In the above-described embodiment, the reinforcing plate 20 is attached to the seismic wall 2 provided with the opening 14 for reinforcement. However, the present invention is not limited to such a case. This includes the case where the reinforcing plate 20 is attached to the seismic wall 2 on which the 14 is not provided for reinforcement.

  In the above-described embodiment, the reinforcing plates 20 are attached to both surfaces of the earthquake-resistant wall 2. However, the present invention is not limited to such a case, and the reinforcement is applied to only one surface of the earthquake-resistant wall 2. The plate 20 may be attached.

  In addition, the fixing member 22 may be omitted when the bonding strength between the reinforcing plates 20 and the wall surface portion of the earthquake-resistant wall 2 can be sufficiently ensured only by adhesion.

It is the front view which showed one Embodiment of the earthquake-resistant wall which concerns on this invention. It is arrow sectional drawing when cut | disconnecting by the A-A 'line | wire in FIG. It is the longitudinal cross-sectional view which showed the internal reinforcement structure of the earthquake-resistant wall shown in FIG. It is the perspective view which showed other embodiment of the reinforcement board which concerns on this invention. It is a cross-sectional view which shows a state when the reinforcement board shown in FIG. 4 is arrange | positioned in the opening part of an earthquake-resistant wall. It is explanatory drawing of the earthquake-resistant wall used for the test for investigating the effect of the earthquake-resistant wall which concerns on this invention. It is the graph which showed the test result for investigating the effect of the shear wall which concerns on this invention. It is the graph which showed the test result for investigating the effect of the shear wall which concerns on this invention.

Explanation of symbols

2 Seismic wall 4 Concrete column part 6 Concrete beam part 8 Vertical bar 10 Horizontal bar 12 Column main bar 14 Opening part 20 Reinforcement plate 22 Fixing member 24 Bolt 30 Reinforcement plate

Claims (6)

A seismic wall characterized in that a plurality of strip-shaped reinforcing plates are attached to both sides or one side with a space in the vertical direction so that the longitudinal direction thereof is a horizontal direction . The earthquake-resistant wall according to claim 1, wherein the reinforcing plate is formed of a steel plate.   The earthquake-resistant wall according to claim 1, wherein the reinforcing plate is formed of a fiber reinforced resin including reinforcing fibers extending in a longitudinal direction. The earthquake resistant wall according to any one of claims 1 to 3, further comprising an opening. 5. The earthquake-resistant wall according to claim 4 , wherein the reinforcing plate is formed in an L-shaped cross section and is disposed along the inner peripheral surface of the opening from the wall surface of the earthquake-resistant wall. A method for reinforcing a seismic wall, comprising attaching a plurality of strip-shaped reinforcing plates on both sides or one side of the seismic wall with a vertical interval therebetween so that the longitudinal direction thereof is a horizontal direction .

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