JP3690468B2 - Seismic reinforcement structure - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seismic reinforcement structure suitable for use in the seismic reinforcement of buildings such as buildings and condominiums.
[0002]
[Prior art]
Conventionally, in order to improve the earthquake resistance of existing buildings, various structures and construction methods have been developed and provided to increase the proof stress by reinforcing members such as columns, beams, walls, and floors.
Needless to say, new buildings are designed and constructed to provide the required earthquake resistance.
[0003]
[Problems to be solved by the invention]
However, the conventional techniques as described above have the following problems.
That is, even when a member is reinforced in an existing building or in a newly built building, for example, in the case of a reinforced concrete structure, the number of reinforcing bars to be used and the diameter are usually changed on the intermediate floor. Such a portion becomes a weak layer with weaker rigidity and yield strength than other layers, and it is inevitable that an unbalance between the yield strength and rigidity of the entire building occurs. Therefore, when a strong earthquake occurs, energy concentrates on the weak layer and damage is concentrated.
[0004]
In addition, it is normal that the upper floors of buildings have margins in proof stress, and as a result, it can be said that the upper floors have more seismic performance than the lower floors.
[0005]
Furthermore, in recent years, there are an increasing number of cases where seismic structures that use relative displacement of each floor and absorb relative displacement energy with various damping devices such as dampers are applied as effective construction methods to reduce earthquake response. Even in such a case, there is also a problem that the effectiveness of the vibration control device is not uniform on each floor due to the imbalance between rigidity and proof strength of each floor.
[0006]
In addition, in order to improve the earthquake resistance of existing buildings, there is always a demand for technology that allows construction to be performed while using the buildings.
[0007]
The present invention has been made in consideration of the above points, and provides an earthquake-resistant reinforcement structure that can relax energy concentration in a layer with weak proof strength and rigidity and obtain efficient earthquake resistance. Let it be an issue.
[0008]
[Means for Solving the Problems]
According to the first aspect of the present invention, a reinforcing frame having rigidity substantially equal to or higher than that of a structure is pin-bonded to the base and top of the structure, and installed from the base to the top along the outer surface of the structure. The reinforcing frame intermediate portion is joined to the structure at an interval determined by the seismic reinforcement structure, and the reinforcing frame has one pair of one end joined to a pin and extending diagonally. and diagonal members, the longitudinal members extending in the vertical direction between the upper and lower the oblique material consists erection has been a crosspiece between the left and right of the vertical member, the water square between said structure and said reinforcing frame It is characterized by being joined so as to allow relative displacement determined in the direction.
[0009]
When the structure is deformed by an earthquake or the like, the structure itself is subjected to a response deformation that is largely deviated with respect to a straight line connecting the top portion and the base portion of the structure with a layer having weak proof strength and rigidity. At this time, since the reinforcing frame is installed from the base portion to the top portion of the structure, the reinforcing frame suppresses deformation in the layer having weak proof strength and rigidity and forces deformation to other layers having small deformation. Moreover, when the horizontal relative displacement between the reinforcement frame and the structure is equal to or less than a predetermined displacement, the deformation of the structure is not transmitted to the reinforcement frame, but is transmitted when the displacement exceeds a predetermined displacement. .
[0010]
The rigidity of the reinforcing frame is determined by the degree of rigidity unbalance of the structure, but is preferably 1 to 30 times the rigidity of the structure.
[0013]
The invention according to claim 2 is the earthquake-proof reinforcement structure according to claim 1 Symbol placement, it is characterized in that the damper is integrated into the reinforcing frame.
[0014]
Thereby, the energy of the deformation of the structure transmitted to the reinforcing frame is absorbed by the damper.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a seismic reinforcement structure according to the present invention will be described with reference to FIGS. 1 to 9.
[0016]
In FIG. 1, reference numeral 1 denotes a building (structure) to be seismically reinforced, and 2 denotes a reinforcing frame.
As shown in this figure, the reinforcing frame 2 is installed along the side surface of a four-story building 1, for example, and is joined to the base 1a and the top 1b of the building 1 via pins 3A and 3B. ing.
[0017]
The reinforcing frame 2 has one end joined to the pins 3A and 3B, and a pair of diagonal members 4a extending diagonally, a vertical member 4b extending vertically between the upper and lower diagonal members 4a, and the building 1 The main frame is composed of a frame main body 4 assembled in a substantially ladder shape with a horizontal member 4c installed between left and right vertical members 4b, 4b at the floor level of each floor. The frame body 4 includes a brace material 5 incorporated in each layer on the intermediate floor.
[0018]
Further, two pairs of brace dampers 6 are incorporated in the frame body 4 so as to correspond to the respective layers of the building 1.
[0019]
The rigidity of the reinforcing frame 2 having such a configuration is set to, for example, 1 to 30 times the rigidity of the building 1 itself.
[0020]
As shown in FIG. 2, the frame body 4 is joined to the bracket 7 whose intermediate portion is fixed by using the in-plane rigidity of the floor and the veranda of each layer of the building 1 as follows. . The cross member 4 c of the frame body 4 is provided with a joint plate 8 extending toward the building 1, and a plurality of long holes 9 are formed in the joint plate 8. Each long hole 9 is a long hole having a long diameter in the horizontal direction along the side surface of the building 1, and a joining pin 10 integrally attached to the bracket 7 is inserted into the long hole 9. The joining pin 10 is engaged so as to be movable within the range of the long diameter direction of the long hole 9.
[0021]
In the building 1 including the reinforcing frame 2 having such a configuration, when the building 1 is deformed due to an earthquake or the like, the building 1 itself is a straight line connecting the base 1a and the top 1b with a layer having weak proof strength and rigidity. It undergoes a response deformation that deviates greatly. At this time, since the reinforcing frame 2 is installed from the base 1a to the top 1b of the building 1, the bending resistance of the reinforcing frame 2 suppresses deformation of the layer having weak proof strength and rigidity, and other layers with small deformation. Force deformation. By the way, since such an effect is not exerted by following the building 1 if the rigidity of the reinforcing frame 2 is low, the rigidity of the reinforcing frame 2 is 1 to 30 relative to the rigidity of the building 1 as described above. It is preferable to set to double.
[0022]
Further, the reinforcing frame 2 is joined to each layer of the building 1 via the long hole 9 and the joining pin 10, so that the deformation amount in each layer of the building 1 is within the range of the major axis direction of the long hole 9. In some cases, since the joining pin 10 does not reach the end of the long hole 9, the deformation of the building 1 is not transmitted to the reinforcing frame 2, and the deformation amount of the building 1 exceeds the range of the long diameter direction of the long hole 9. Only when the joining pin 10 comes into contact with the end of the long hole 9, the deformation of the building 1 is transmitted to the reinforcing frame 2.
[0023]
The deformation energy of the building 1 transmitted to the reinforcing frame 2 is converted into thermal energy by the brace damper 6 incorporated in the reinforcing frame 2 and absorbed.
[0024]
In the above-mentioned seismic reinforcement structure, the reinforcement frame 2 having a rigidity substantially equal to or higher than that of the building 1 is installed from the base 1a to the top 1b along the outer surface of the building 1, and the intermediate portion is provided on each floor of the building 1. It has a joined structure.
As a result, when deformation occurs in the building 1 due to an earthquake or the like, the bending resistance of the reinforcing frame 2 suppresses the deformation of the weak layer that largely deviates from the straight line connecting the base 1a and the top 1b of the building 1 and Can force deformation to other small layers. Therefore, the deformation of the building 1 at the time of the earthquake can be made uniform in each layer, and as a result, the seismic energy is evenly consumed in each layer of the building 1, and high earthquake resistance performance is exhibited by preventing energy concentration in a specific layer. be able to.
[0025]
Moreover, since the reinforcement frame 2 can be attached to the building 1 only by external work, it is possible to perform the work while using the building 1 even when the building 1 is an existing one. Further, since there is almost no increase in load or the like for the foundation portion of the building 1, it is particularly advantageous in the existing building 1. Furthermore, the reinforcing frame 2 itself has a simple structure.
[0026]
In this way, the total required cost can be significantly reduced by reinforcing the building 1 with earthquake resistance with the reinforcing frame 2.
[0027]
Further, the reinforcing frame 2 is joined to the base 1a and the top 1b of the building 1 and joined to each floor of the building 1 by joining through the long holes 9 and the joining pins 10 so that the reinforcing frame 2 It is the structure which accept | permits the relative displacement defined in the horizontal direction between 2 and the building 1. FIG. Thereby, only when the horizontal relative displacement between the reinforcing frame 2 and the building 1 is equal to or greater than the predetermined displacement, the deformation of the building 1 is transmitted to the reinforcing frame 2 and the deformation is forced to other layers. It has become so.
Therefore, for example, even in the case of an earthquake that does not damage the weak layer of the building 1 even with the conventional structure, the deformation is not forced by the reinforcing frame 2 and the deformation in the layers other than the weak layer does not become excessively large. Can be.
[0028]
Further, the reinforcing frame 2 has a configuration in which a brace damper 6 is incorporated. Thereby, the deformation energy of the building 1 transmitted to the reinforcement frame 2 is absorbed, and the seismic energy can be attenuated efficiently. In addition, the brace damper 6 provided in each layer can be used equally on each floor by the action of the reinforcing frame 2.
[0029]
Here, what is shown in FIG. 3 thru | or FIG. 5 examined the earthquake response in the building model to which the structure as described above is applied.
In the following examination, the seismic wave is assumed to be El Centro1940NS (maximum velocity is normalized to 50 kine). The building will be a three-story reinforced concrete structure with 7m x 5 spans in the girder direction and 5.5 m x 3 spans in the beam-to-beam direction. The total weight of the building during the earthquake shall be 1605 (t). And in such a building, the restoring force characteristic was analyzed as a Tri-Linear Takeda model about the direction of a girder which has few seismic walls and is prone to earthquake damage.
[0030]
FIG. 3 shows the result when the rigidity and proof stress of the first layer of the building 1 are intentionally reduced to ½ to form a weak layer. In the figure, “Original Model” corresponds to the case where the reinforcing frame 2 is not present, and the plastic history is concentrated on the first layer, and the history of the second and third layers is less than the yield deformation. .
In the figure, what is indicated as “rigid rod” corresponds to the case where the reinforcing frame 2 is attached with 10 times the rigidity of the building 1, and loose joining via the long hole 9 and the joining pin 10. When the damper-type brace 6 is abolished (indicated as “no gap” in the figure), the deformation of the first layer, which is a weak layer, significantly forces the response displacement of the third layer.
However, when the damper-type brace 6 is abolished by adopting loose joining (giving a gap corresponding to the yield displacement δy of each layer of the building 1) via the long hole 9 and the joining pin 10 (“gap δy” in the figure). ), The response displacement forced on the third layer is reduced, and a linear deformation connecting the base 1a and the top 1b of the building 1 is obtained.
From the above, the effect of loose joining between the reinforcing frame 2 and the building 1 via the long hole 9 and the joining pin 10 can be confirmed.
[0031]
4 and 5 show the response displacement and the response plasticity rate when the reinforcing frame 2 (the rigidity is 3 times the rigidity of the building because there is no significant weak layer) is attached to the building 1 having no significant weak layer.
In FIG. 4 and FIG. 5, the “rigid rod body model” is a case where loose joining via the long hole 9 of the reinforcing frame 2 and the joining pin 10 is adopted and the damper brace 6 is eliminated. Equivalent to. In this case, it can be confirmed that the response plasticity rate of each floor is equalized by the reinforcing frame 2 including the third layer that has been playing with the seismic performance.
Further, in FIG. 4 and FIG. 5, the “rigid rod damper model” employs loose joints through the long holes 9 of the reinforcing frame 2 and the joining pins 10 and the damper type brace 6 is adopted. It corresponds to the case. In this case, the response of each floor is equalized and reduced, and the response plasticity ratio (magnification of response displacement with respect to the yield displacement of the floor) is remarkably reduced to μ = 0.83 to 1.53. This is a response that does not require any seismic reinforcement as long as the response reduction of this level is obtained even if the building 1 is a reinforced concrete structure in which the existing building is ineligible.
[0032]
In the analysis conditions shown in FIG. 3 to FIG. 5, it is sufficient that the reinforcing frame 2 has a rigidity of about 3 to 30 times the rigidity of the building 1, for example, H-100 × 50 × The required rigidity can be ensured if the reinforcing frame 2 is formed by providing two 7-span truss structures with 5 × 7 steel, and the response bending stress of the reinforcing frame 2 is the short-term allowable stress level. Fits to the extent.
[0033]
In the first embodiment, the brace damper 6 is used as a damper incorporated in the reinforcing frame 2, but other dampers are not hindered.
For example, as shown in FIG. 6, for example, a viscous damper 12 is incorporated between the bracket 11 incorporated in the cross member 4 c of the frame body 4 of the reinforcing frame 2 and the cross member 4 c on the upper floor. Alternatively, as shown in FIG. 7, instead of the viscous damper 12 in FIG. 6, a shear yield type or bending shear yield type damper 13 may be incorporated. In addition, the type of the damper incorporated in the reinforcing frame 2 is not limited at all, and any damper may be incorporated as long as it can exhibit a required function. Of course, in some cases, it is possible to adopt a configuration in which the damper is omitted.
[0034]
In addition, as shown in FIG. 8, when the building 1 cannot attach a reinforcing frame to a girder surface such as an apartment house, the reinforcing frame 22 is connected to a girder surface such as an outer staircase surface of both wife surfaces. You may install in the side surfaces 1c and 1d orthogonal to. Here, the reinforcing frame 22 includes a frame body 4 installed on one side surface 1c of the building 1 and a damper frame 23 installed on the other side surface 1d. The frame body 4 divided and installed in this way is attached to the bracket 7 provided on each floor of the side surface 1c of the building 1 in the same manner as the reinforcing frame 2 (see FIG. 1) shown in the first embodiment. Loose joining is performed through the hole 9 and the joining pin 10. The damper frame 23 has a structure in which a damper 25 for absorbing deformation energy in each floor is incorporated in a frame main body 24 fixed to the other side surface 1d of the building 1.
[0035]
Such a reinforcing frame 22 can also exhibit the same function as the reinforcing frame 2 shown in the above embodiment. In addition, by separately installing the frame main body 4 constituting the reinforcing frame 22 and the damper frame 23 in this way, it is possible to improve the seismic performance without impairing the use environment of the building 1.
[0036]
In addition, as shown in FIG. 9, when an elevator shaft 32 that is continuous in the vertical direction is installed at the center of the building 31, the reinforcing frame 2 may be installed along the side surface of the elevator shaft 32. Is possible. Such an elevator shaft 32 is cylindrical and has higher rigidity than other parts of the building 31, and constitutes the core of the building 31.
[0037]
In addition, in the said embodiment, it was set as the structure which joins the reinforcement frame 2 to each floor of the buildings 1 and 31, but it is also possible to join at other intervals, for example, every 2nd floor or every 3rd floor.
Further, the frame body 4 constituting the reinforcing frame 2 is not limited to any form, and a form capable of obtaining a required bending resistance, such as a plane truss shape or a solid truss shape, may be appropriately adopted. Of course, there is no question about the material of the members constituting the frame body 4.
Further, the structure of the portion where the reinforcing frame 2 is joined to the buildings 1 and 31, that is, the pin joining via the pins 3 A and 3 B at the upper and lower ends of the reinforcing frame 2, and the long holes 9 and the joining pins 10 in each layer of the middle As for the loose joint, other joint structures may be used.
[0038]
In addition, the building to which the seismic reinforcement structure as described above is applied does not ask whether it is newly built or existing.
Further, the locations where the reinforcing frames 2 are installed and the number of the reinforcing frames 2 may be set as appropriate so as to obtain the required seismic reinforcing effect, and are not limited to the above embodiment.
[0039]
Other than this, as long as it does not deviate from the gist of the present invention, any configuration may be adopted, and it is needless to say that the above-described configurations may be appropriately combined.
[0040]
【The invention's effect】
As described above, according to the seismic reinforcement structure according to claim 1, the reinforcement frame having rigidity substantially equal to or higher than that of the structure is pin-joined to the base portion and the top portion of the structure, so that the outside of the structure It is installed from the base portion to the top portion along the side surface, and the intermediate portion is joined at intervals determined by the structure.
Thereby, when a deformation | transformation arises in a structure by an earthquake etc., a reinforcement frame can suppress a deformation | transformation in a layer with weak yield strength and rigidity, and can force a deformation | transformation to another layer with a small deformation | transformation. Therefore, the deformation of the structure at the time of an earthquake can be made uniform in each layer and the seismic energy can be consumed uniformly in each layer, energy concentration in a specific layer can be prevented, and high earthquake resistance performance can be exhibited.
In addition, since the installation of the reinforcing frame to the structure requires only an external work, even when the structure is an existing structure, the work can be performed while using the structure.
In addition, since the reinforcing frame has a simple structure, there is almost no increase in load on the foundation portion of the structure, which is particularly advantageous in the case of seismic retrofitting of existing structures.
Furthermore, the reinforcing frame itself has a simple structure.
Since it is possible to cope with the construction outside the building, the total cost required for the seismic retrofitting can be significantly reduced, for example, about half of the ordinary seismic reinforcement construction method.
[0041]
Further, according to the earthquake-proof reinforcement structure according to claim 1, the reinforcing frame, the portion that is joined to the structure, is configured to permit relative displacement defined in the horizontal direction between the reinforcing frame and the structure ing.
As a result, when the horizontal relative displacement between the reinforcing frame and the structure is equal to or less than the predetermined displacement, the deformation of the structure is not transmitted to the reinforcing frame, but is transmitted when the displacement exceeds the predetermined displacement. The Therefore, for example, in the case of an earthquake with a strength that does not damage the weak layer of the structure even in the conventional structure, it is possible to prevent deformation by the reinforcing frame, and excessive deformation in the layers other than the weak layer is excessive. You can prevent it from getting bigger.
[0042]
According to the seismic reinforcement structure according to the second aspect , the damper is incorporated in the reinforcement frame. Thereby, the deformation energy of the structure transmitted to the reinforcing frame is absorbed by the damper, and the seismic energy can be efficiently absorbed. Moreover, when the dampers are provided in the respective layers, the dampers of the respective layers can be used equally by the action of the reinforcing frame.
[Brief description of the drawings]
FIG. 1 is an elevational view showing an example of an embodiment of a seismic reinforcement structure according to the present invention.
2A is a view as viewed from the arrow of FIG. 1, and FIG. 2B is a view as viewed from the arrow of FIG.
FIG. 3 is a diagram showing a seismic response analysis result in a building model to which the seismic reinforcement structure according to the present invention is applied.
FIG. 4 is a diagram showing another seismic response analysis result.
FIG. 5 is a diagram showing still another seismic response analysis result.
FIG. 6 is an elevational view showing another example of the embodiment of the seismic reinforcement structure according to the present invention.
FIG. 7 is an elevational view showing still another example of the embodiment of the seismic reinforcement structure according to the present invention.
FIG. 8 is an elevational view showing still another example of the embodiment of the seismic reinforcement structure according to the present invention.
FIG. 9 is an elevational view showing still another example of the embodiment of the seismic reinforcement structure according to the present invention.
[Explanation of symbols]
1,31 Building 2,22 Reinforcement frame 6 Brace type damper (damper)
12, 13, 25 Damper

Claims (2)

A reinforcing frame having a rigidity substantially equal to or higher than that of the structure is pin-bonded to the base and top of the structure, and is installed from the base to the top along the outer surface of the structure. Is a seismic reinforcement structure that is joined at intervals defined in the structure,
The reinforcing frame has one end joined to a pin and extends diagonally between two pairs of diagonal members, a vertical member extending vertically between the upper and lower diagonal members, and a bridge between the vertical members on the left and right sides. It has been a consist crosspiece, seismic reinforcement structure, characterized in that it is joined so as to allow relative displacement defined in the horizontal direction between said structure and said reinforcing frame.   The seismic reinforcement structure according to claim 1, wherein a damper is incorporated in the reinforcement frame.

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