Adjacent building structure

Abstract

To enhance damping performance of one building constructed adjacent to the other building having high damping performance.SOLUTION: An adjacent building structure 50 includes: a first building 100 supported by a first direct foundation 150 and having a first basement floor 120; a second building 200 constructed adjacent to and facing the first building 100, having the same scale as the first building 100, having higher damping characteristics than the first building 100, supported by a second direct foundation 250, and having a second basement floor 220; and an underground space part 300 exposing a first underground outer wall 120A and a second underground outer wall 220A adjacently facing each other from the first direct foundation 150 of the first building 100 and the second direct foundation 250 of the second building 200 to a ground surface 10A.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to adjacent building structures. [Background technology]

[0002] Patent Document 1 discloses technology relating to a protection structure and protection method that can avoid or mitigate damage caused by unequal settlement of adjacent buildings in the event of ground liquefaction, etc. In this prior art, an adjacent building protection structure is configured by including a first underground structure installed in a first building, a second underground structure installed in a second building adjacent to the first building, and a buffer member arranged across the first and second underground structures.

[0003] Patent Document 2 discloses a technology related to earthquake-resistant underground structures that is mainly applied when structures with different vibration characteristics are installed next to each other. In this prior art, the soft ground that is the ground area extending between adjacent structures is replaced with a deformation absorbing area near the ground surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-110454 [Patent Document 2] Japanese Patent Application Publication No. 11-323960 Summary of the Invention [Problem to be solved by the invention]

[0005] It is known that the shaking of buildings during earthquakes can be suppressed by increasing the damping capacity of the building through the use of vibration control devices such as vibration dampers and mass dampers installed in the building. For adjacent buildings, vibration control devices are installed on each building to suppress shaking.

[0006] Here, if one building with high damping performance can be used to improve the damping performance of another building constructed adjacent to it, it will be possible to reduce construction costs, for example.

[0007] Alternatively, if one building with high damping performance can be used to improve the damping performance of another adjacent building, for example, there will be no need to install a vibration control device in the other building, or the number of vibration control devices installed can be reduced, allowing for more spacious use of the interior space.

[0008] In view of the above, an object of the present invention is to improve the damping performance of a building constructed adjacent to another building having high damping performance. [Means for solving the problem]

[0009] The first aspect is an adjacent building structure comprising a first building supported on a direct foundation and having a basement floor; a second building constructed adjacent to and facing the first building, having the same scale as the first building but higher damping characteristics than the first building, supported on a direct foundation and having a basement floor; and an underground space portion in which adjacent and opposing underground exterior walls of the first and second buildings are exposed from the direct foundations to the ground surface.

[0010] In the first adjacent building structure, an underground space is provided from the foundations of adjacent and opposing first and second buildings of the same size to the ground surface, and the adjacent and opposing underground exterior walls are exposed. This reduces the constraint of the basement floor by the ground, making it easier for the rocking behavior of the two buildings to be transmitted via the foundations. During an earthquake, the second building, which has high damping performance, responds to the rocking behavior of the first building and absorbs vibration energy on behalf of the first building, reducing the response of the first building.

[0011] A second aspect is the adjacent building structure described in the first aspect, in which the underground space portion also exposes the underground exterior wall on the opposite side to the adjacent side of the first building and the second building.

[0012] In the second adjacent building structure, the basement exterior walls of the first and second buildings on the opposite side to the adjacent side are exposed, further reducing the constraint on rocking behavior caused by the basement ground. This makes it easier for the rocking behavior of the two buildings to be transmitted to each other, further reducing the response of the first building.

[0013] A third aspect is the adjacent building structure described in the second aspect, in which the underground space portion exposes the underground exterior walls around the entire perimeter of the basement floors of the first building and the second building.

[0014] In the third adjacent building structure, an underground space is formed around the entire periphery of the basement exterior walls of the first and second buildings, which further reduces the constraint on rocking behavior caused by the basement ground. This makes it easier for the rocking behavior of the two buildings to be transmitted to each other, further reducing the response of the first building.

[0015] A fourth aspect is an adjacent building structure described in any one of the first to third aspects, in which the first building and the second building have elevations with an aspect ratio between the building height and the building width of 4 or more, and the orientation of the elevations of the first building and the second building is the same.

[0016] In the fourth type of adjacent building structure, the first and second buildings, when viewed in plan, exhibit large rocking behavior along the direction of the elevation where the aspect ratio of the building height to the building width is 4 or more, so the second building, which has high damping performance, effectively absorbs vibration energy in place of the first building, reducing the response of the first building. [Effects of the Invention]

[0017] According to the present invention, it is possible to improve the damping performance of a building constructed adjacent to another building having high damping performance. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1A is a cross-sectional view taken along the X direction, schematically illustrating an adjacent building structure according to one embodiment of the present invention, and FIG. 1B is a plan view. [Figure 2]10A is a cross-sectional view taken along the X direction and schematically showing the adjacent building structure of the first modified example, and FIG. 10B is a plan view. [Figure 3] 10A is a cross-sectional view along the X direction schematically showing the adjacent building structure of the second modified example, and FIG. 10B is a plan view. [Figure 4] 10(A) is a cross-sectional view taken along the X direction and showing a schematic diagram of the adjacent building structure of the third modified example, and FIG. 10(B) is a plan view. [Figure 5] 10A is a cross-sectional view along the X direction schematically showing the adjacent building structure of the fourth modified example, and FIG. 10B is a plan view. [Figure 6] 10A is a cross-sectional view along the X direction that schematically shows the structure of an adjacent building in a comparative example, and FIG. 10B is a plan view. [Figure 7] (A) is a numerical analysis model of the adjacent building structure of the comparative example in FIG. 6, and (B) is a numerical analysis model of the adjacent building structure in FIG. [Figure 8] 7(A) shows the analysis results of the numerical analysis model of the comparative example. [Figure 9] 7B shows the analysis results of the numerical analysis model of the embodiment of FIG. [Figure 10] FIG. 10 is an explanatory diagram illustrating the transmission of a rocking phenomenon. [Figure 11] 3 shows the results of a numerical analysis of the adjacent building structure of the first modified example of FIG. 2. [Figure 12] 4 shows the results of a numerical analysis of the adjacent building structure of the second modified example of FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0019] <Embodiment> An adjacent building structure according to one embodiment of the present invention will be described. The two directions that intersect at right angles to the horizontal direction are the X direction and the Y direction, and are indicated by the arrows X and Y, respectively. The vertical direction that intersects at right angles to the X direction and the Y direction is the Z direction, and is indicated by the arrow Z.

[0020] [structure] First, a specific structure of the adjacent building structure according to one embodiment of the present invention will be described.

[0021] As shown in Figures 1(A) and 1(B), the adjacent building structure 50 is composed of two buildings, a first building 100 and a second building 200, constructed adjacent to and facing each other on the ground 10, and an underground space 300 formed in the ground 10. The ground 10 in the figures is the surface ground.

[0022] In this embodiment, the first building 100 and the second building 200 are both made of reinforced concrete, but are not limited to this. They may also be made of steel, steel-framed reinforced concrete, or wood. Furthermore, the first building 100 and the second building 200 may be constructed using a combination of reinforced concrete, steel, steel-framed reinforced concrete, and wood.

[0023] The first building 100 is rectangular in plan view (see FIG. 1(B)), has a first above-ground floor 110 and a first basement floor 120, and is supported by a first spread foundation 150. The first building 100 is an earthquake-resistant building that is not equipped with a vibration control device. The four exterior walls of the first basement floor 120, which is rectangular in plan view, are referred to as first underground exterior walls 120A, 120B, 120C, and 120D. The four elevations of the first above-ground floor 110 are referred to as first elevations 110A, 110B, 110C, and 110D.

[0024] The second building 200 is rectangular in plan view (see FIG. 1(B)), has a second ground floor 210 and a second basement floor 220, and is supported by a second spread foundation 250. The second building 200 is a building with a vibration control structure in which vibration control dampers 90 (FIG. 1(A)) as an example of a vibration control device are provided on each floor. The exterior walls of the second basement floor 220, which is rectangular in plan view, are referred to as second basement exterior walls 220A, 220B, 220C, and 220D. The four elevations of the second ground floor 210 are referred to as second elevations 210A, 210B, 210C, and 210D.

[0025] The first building 100 and the second building 200 are constructed adjacent to each other, and the planar shapes of the first basement floor 120 and the second basement floor 220 are the same as the first aboveground floor 110 and the second aboveground floor 210. In addition, the first elevation 110A and the second elevation 210A face each other, and the first underground exterior wall 120A and the second underground exterior wall 220A face each other.

[0026] In this embodiment, the distance between the first building 100 and the second building 200, that is, the distance between the opposing first elevation 110A and first underground outer wall 120A, and the opposing second underground outer wall 220A and second elevation 210A, is 1 m. The distance between the first building 100 and the second building 200 is preferably 5 m or less, and more preferably about 1 m.

[0027] Here, the second building 200 is provided with vibration dampers 90 on each floor, but is not limited to this. Vibration dampers 90 may be provided on some floors. It is sufficient that the second building 200 is provided with a vibration damping device that absorbs energy and suppresses shaking. Examples of vibration damping devices include a vibration damper 90 provided inside a building as shown in FIG. 1(A) and a mass damper provided on the roof of a building. Examples of the vibration damper 90 include an oil damper, a viscoelastic damper, and a hysteretic damper. Examples of the mass damper include a tuned mass damper (TMD) and an active mass damper (AMD).

[0028] The vibration damper 90 shown in FIG. 1(A) is installed on the X-direction structural face and exerts a vibration damping effect against shaking in the X direction.

[0029] 1(A) and 1(B), the first building 100 and the second building 200 are generally of the same scale. The same scale means that the building height from the ground surface 10A, the planar shape, and the natural frequency are the same or approximately the same.

[0030] In this embodiment, the building height of each of the first building 100 and the second building 200 is 60 m, but is not limited to this.

[0031] In addition, the first building 100 and the second building 200 in this embodiment are rectangular in shape in plan view, with the building width of the first elevations 110B, 110D and second elevations 210B, 210D, which are the short sides, being 15 m, and the building width of the first elevations 110A, 110C and second elevations 210A, 210C, which are the long sides, being 30 m, but this is not limited to this. However, it is desirable for the aspect ratio of the building height to the building width of each elevation to be 4 or more. In this embodiment, the aspect ratio of the first elevations 110B, 110D and second elevations 210B, 210D is 4.

[0032] In addition, in this embodiment, the first elevations 110B and 110D of the first building 100 and the second elevations 210B and 210D of the second building 200 have the same orientation. Specifically, the first elevations 110B and 110D, which have an aspect ratio of 4 between the building height and the building width, and the second elevations 210B and 210D of the second building 200 have the same in-plane direction in a plan view and are on the same line. However, the first elevations 110B and 110D and the second elevations 210B and 210D of the second building 200 do not have to have exactly the same orientation. The first elevations 110B and 110D and the second elevations 210B and 210D of the second building 200 may be offset in the Y direction.

[0033] As described above, the out-of-plane directions of the first elevations 110B and 110D of the first building 100 and the second elevations 210B and 210D of the second building 200 in this embodiment are parallel to each other in the same Y direction when viewed from above. Similarly, the out-of-plane directions of the first elevations 110A and 110C of the first building 100 and the second elevations 210A and 210C of the second building 200 in this embodiment are parallel to each other in the same X direction when viewed from above. However, this is not limited to this. The elevations may not be parallel to each other, but may be slightly angled.

[0034] In addition, the depth of the first foundation bottom 150A and the second foundation bottom 250A, which are the bottom surfaces of the first spread foundation 150 and the second spread foundation 250 in this embodiment, is 7 m. In other words, the distance from the first floor to the foundation bottom is 7 m. However, this is not limited to this, and the depth may be less than 7 m or may be 7 m or more.

[0035] Furthermore, in this embodiment, the natural frequencies of the first building 100 and the second building 200 are approximately the same, with the first order being 0.67 Hz and the second order being 1.77 Hz, but this is not limiting.

[0036] In addition, the ground 10 on which the first building 100 and the second building 200 in this embodiment are constructed is soft or becomes soft due to distortion during an earthquake. The ground 10 in this embodiment has a shear velocity of about 200 m / s, which indicates the hardness of the ground.

[0037] The ground 10 from the first foundation bottom 150A of the first spread foundation 150 and the second foundation bottom 250A of the second spread foundation 250 around the first basement floor 120 of the first building 100 and the second basement floor 220 of the second building 200 to the ground surface 10A has been removed to form an underground space portion 300. The underground space portion 300 exposes the first underground outer walls 120A, 120B, 120C, 120D and the second underground outer walls 220A, 220B, 220C, 220D from the first foundation bottom 150A of the first spread foundation 150 and the second foundation bottom 250A of the second spread foundation 250 to the ground surface 10A.

[0038] As described above, the distance between the first underground outer wall 120A and the second underground outer wall 220A in the underground space portion 300 is 1 m. In addition, the distance between the first underground outer walls 120B, 120C, 120D and the second underground outer walls 220B, 220C, 220D in the underground space portion 300 and the wall surface 300A of the underground space portion 300 is 1 m, but is not limited to this.

[0039] A cover member such as an expansion joint (not shown) is provided in the gap between the ground surface 10A in the underground space 300 and the first building 100 and second building 200. Rainwater that has entered the underground space 300 is drained by a drainage mechanism (not shown).

[0040] [Effect] Next, the operation of this embodiment will be described.

[0041] In the adjacent building structure 50 of this embodiment, an underground space portion 300 is formed that exposes the first underground outer walls 120A, 120B, 120C, and 120D of the first underground floor 120 and the second underground outer walls 220A, 220B, 220C, and 220D of the second underground floor 220 of the first building 100 and second building 200 that are constructed adjacent to and facing each other and are of the same scale. Therefore, compared to when the underground space portion 300 is not formed, the constraint of the first underground floor 120 and the second underground floor 220 by the ground 10 is reduced, and the mutual rocking behavior is more easily transmitted through the ground 10 via the first spread foundation 150 and the second spread foundation 250.

[0042] Therefore, during an earthquake, the second building 200, which has a vibration-control structure and is equipped with a vibration-control damper 90, an example of a vibration-control device, reacts to the rocking behavior of the first building 100, which has an earthquake-resistant structure and is not equipped with a vibration-control device, and absorbs the vibration energy on behalf of the first building 100, thereby reducing the response of the first building 100.

[0043] From another perspective, by forming the underground space portion 300 and reducing the effect of the first basement floor 120 and the second basement floor 220 being restrained by the ground 10, the effect of inertial interaction, in which vibrations of the first building 100 and the second building 200 propagate through the ground 10 and affect each other, is relatively increased. This makes it easier for the second building 200 to absorb vibration energy in place of the first building 100, reducing the response of the first building 100. In other words, the damping performance of the first building 100 constructed adjacent to it is improved by using the second building 200, which has high damping performance.

[0044] Therefore, the response of the two buildings, the first building 100 and the second building 200, can be reduced while reducing costs compared to installing vibration control devices in the first building 100 and the second building 200, which are constructed adjacent to and facing each other and are of the same size.

[0045] In this way, there is no need to install vibration dampers 90 inside the first building 100, which allows for more efficient use of the indoor space inside the first building 100. Furthermore, if the first building 100 is an existing building, there is no need for reinforcement work to improve earthquake resistance.

[0046] Here, in the adjacent building structure 50 of this embodiment, as described above, the vibration damper 90 provided in the second building 200 exerts a vibration damping effect against shaking in the X direction. Therefore, the vibration damper 90 of the second building 200 improves the damping performance of the first building 100 constructed adjacently against shaking in the X direction. This also applies to the modified examples described later.

[0047] In this embodiment, the first building 100 and the second building 200 exhibit large rocking behavior in the X direction (the direction of the short side of the rectangle in plan view) along the first elevations 110B, 110D and second elevations 210B, 220D, whose aspect ratio between the building height and the building width is 4. Therefore, the second building 200, which has high damping performance, effectively absorbs vibration energy in place of the first building 100, reducing the response of the first building 100.

[0048] Next, the phenomenon in which the rocking behavior of the first building 100 and the second building 200 is transmitted to the ground 10 will be described.

[0049] As shown in Figure 10, when the first building 100 (one of the buildings) exhibits rocking behavior, the ground 10 deforms, and this deformation is thought to be transmitted to the second building 200 (the other building). Therefore, the softer the ground 10 is and the more easily it deforms, the more easily rocking behavior is transmitted. Therefore, when applying the present invention, a softer ground 10 is preferable. The softness of the ground 10 can be expressed by the shear rate, which indicates the hardness of the ground. Therefore, the smaller the shear rate, the greater the effect can be expected. Note that Figure 10 is an explanatory diagram that is easy to understand and exaggerated. Therefore, it does not accurately represent the actual behavior of the ground 10.

[0050] The first building 100 and the second building 200 may be existing buildings or new buildings. For example, in order to reduce the response of the existing first building 100, the second building 200 may be newly constructed adjacent to the first building 100. Alternatively, in order to reduce the response of the existing first building 100, the existing second building 200 constructed adjacent to the first building 100 may be retrofitted with vibration damping devices so that it has high damping. Alternatively, in order to reduce the response of the first building 100 to be newly constructed adjacent to the existing second building 200, the existing second building 200 may be retrofitted with vibration damping devices so that it has high damping. Alternatively, both the first building 100 and the second building 200 may be newly constructed adjacent to each other.

[0051] In the center of a large city, multiple mid- to high-rise buildings are often built adjacent to each other to form city blocks. In such blocks, due to issues such as height restrictions, buildings of roughly the same size and shape are often built adjacent to each other. By improving the damping performance of one of the adjacent buildings of the same size (second building 200), the response of the other building (first building 100) is also reduced. Therefore, the present invention is suitable for application to city blocks where multiple buildings of the same size are built adjacent to each other, such as in the center of a large city.

[0052] The application to the above-mentioned block is suitable when vibration control effects in the X direction are expected. For example, it is suitable for application to a block where the first elevation 110A of the first building 100 and the second elevation 210A of the second building 200 are built facing each other.

[0053] Furthermore, it may be difficult to secure space to install a vibration control device in an existing building (first building 100). However, by installing a vibration control device in a newly constructed building (second building 200), it is possible to reduce the response of the existing building (first building 100).

[0054] Furthermore, even if the first building 100 is a newly constructed building, this embodiment can be applied to cases where it is difficult to secure space to install a vibration control device or where it is desired to make wider use of the space without installing a vibration control device.

[0055] [Numerical analysis] Next, we will explain the results of a numerical analysis of modeled first building 100 and second building 200. Specifically, using the analysis software SuperFLUSH / 2D, we performed a pseudo-three-dimensional frequency response analysis that solves the building model and ground model as a single unit.

[0056] (Analysis conditions) Figure 7(B) is a numerical analysis model of the first building 100 and second building 200 shown in Figure 1. The two adjacent buildings, first building 100 and second building 200, have the same building shape, with a planar shape of 15m x 30m, a height above ground of 60m, a floor height above ground of 4m, and a floor height above the first basement of 4.5m. Note that Figure 1 is a schematic illustration for purposes of illustrating the vibration damper 90, and so the number of floors in Figure 1 does not match the number of floors in Figure 7(B). Furthermore, the ground floors and basement floors were modeled as equivalent shear floors, but their rotational degrees of freedom were made dependent on the inclination of the spread foundation and basement exterior wall, which were modeled using rigid elements.

[0057] The mass and rigidity of the two buildings, the first building 100 and the second building 200, were set to be the same. The natural frequencies when the foundations were fixed were 0.67 Hz for the first mode and 1.77 Hz for the second mode. The damping of the buildings was set to complex damping, with the damping constant of the first building 100, which is an earthquake-resistant building, being 2%, and the damping constant of the second building 200, which is a vibration-control building, being 10%.

[0058] The two buildings were adjacent to each other in the short side direction, with a distance of 1 m between them. Reference numeral 10 denotes the surface ground corresponding to the ground 10 in the above embodiment, and reference numeral 12 denotes the deep ground, which were modeled as a two-layer ground. The boundary conditions between the surface ground 10 and the deep ground 12 were an energy transfer boundary on the side and a viscous boundary on the bottom. The shear velocity of the ground 10 was 200 m / s, and the damping constant was 10%. The shear velocity of the deep ground 12 was 400 m / s, and the damping constant was 2%. The depth of the surface ground was 20 m.

[0059] The seismic wave was input at the bedrock at a depth of 180 m. The input wave was an extremely rare earthquake motion (random phase) according to Notification No. 1461 of the Building Standards Act.

[0060] In the ground 10, an underground space portion 300 (see FIG. 1) similar to that of the embodiment is formed.

[0061] 7(A) is a model of an adjacent building structure 55 of a comparative example in which the underground space portion 300 (see FIG. 1) is not formed in the ground 10 shown in FIG. 6, that is, the first basement floor 120 and the second basement floor 220 are constrained by the ground 10. The adjacent building structure 55 of the comparative example is the same as the adjacent building structure 50 of this embodiment (see FIG. 1) in terms of conditions other than the fact that the underground space portion 300 (see FIG. 1) is not formed.

[0062] (Analysis results) First, the case of the adjacent building structure 55 of the comparative example shown in Figs. 6 and 7(A) will be described.

[0063] Figure 8(A) shows the relationship between the amplitude and frequency of the transfer function of the first building 100 in the adjacent building structure 55 of the comparative example, and Figure 8(B) shows the relationship between the building height and maximum story displacement of the first building 100. Figure 8(C) shows the relationship between the amplitude and frequency of the transfer function of the second building 200 in the adjacent building structure 55 of the comparative example, and Figure 8(D) shows the relationship between the building height and maximum story displacement of the second building 200.

[0064] The solid line in Figure 8(A) represents the case where the first building 100 and the second building 200 are constructed adjacent to each other, and the dashed line represents the case where only the first building 100 is constructed. From the graph in Figure 8(A), it can be seen that the amplitude of the first mode of the first building 100, which is an earthquake-resistant building, is slightly amplified when the first building 100 and the second building 200 are constructed adjacent to each other (solid line) compared to when the first building 100 is constructed alone (dashed line).

[0065] The solid line in Figure 8(C) represents the case where the first building 100 is constructed adjacent to the second building 200, and the dashed line represents the case where only the second building 200 is constructed. From the graph in Figure 8(C), it can be seen that there is little difference in the amplitude of the first mode of the second building 200, which is a vibration-controlled building, between the case where the first building 100 and the second building 200 are constructed adjacent to each other (solid line) and the case where the second building 200 is constructed alone (dashed line).

[0066] In Figure 8(B), black triangles (▲) indicate cases where the first building 100 and the second building 200 are constructed adjacent to each other, and white circles (◯) indicate cases where only the first building 100 is constructed. From the graph in Figure 8(B), it can be seen that the maximum inter-story displacement of some stories of the first building 100, which is an earthquake-resistant structure, is larger when the first building 100 and the second building 200 are constructed adjacent to each other (black triangles (▲)) than when the first building 100 is constructed alone (white circles (◯)).

[0067] In Figure 8(D), black triangles (▲) represent the case where the first building 100 and the second building 200 are constructed adjacent to each other, and white circles (◯) represent the case where only the second building 200 is constructed. From the graph in Figure 8(D), it can be seen that there is little difference in the maximum story displacement of the second building 200, which is a vibration-controlled building, between the case where the first building 100 and the second building 200 are constructed adjacent to each other (black triangles (▲)) and the case where the second building 200 is constructed alone (white circles (◯)).

[0068] Next, the case of the adjacent building structure 50 of this embodiment will be described.

[0069] Figure 9(A) shows the relationship between the amplitude and frequency of the transfer function of the first building 100 in the adjacent building structure 50 of this embodiment, and Figure 9(B) shows the relationship between the building height and maximum story displacement of the first building 100. Figure 9(C) shows the relationship between the amplitude and frequency of the transfer function of the second building 200 in the adjacent building structure 50 of this embodiment, and Figure 9(D) shows the relationship between the building height and maximum story displacement of the second building 200.

[0070] The solid line in Figure 9(A) represents the case where the first building 100 and the second building 200 are constructed adjacent to each other, and the dashed line represents the case where only the first building 100 is constructed. From the graph in Figure 9(A), it can be seen that the amplitude of the first mode of the first building 100, which is an earthquake-resistant building, is significantly reduced when the first building 100 and the second building 200 are constructed adjacent to each other (solid line) compared to when the first building 100 is constructed alone (dashed line).

[0071] The solid line in Figure 9(C) represents the case where the first building 100 and the second building 200 are constructed adjacent to each other, and the dashed line represents the case where only the second building 200 is constructed. From the graph in Figure 9(C), it can be seen that there is little difference in the amplitude (solid line) of the first mode of the second building 200, which is a vibration-controlled building, between the case where the first building 100 and the second building 200 are constructed adjacent to each other (solid line) and the case where the second building 200 is constructed alone (dashed line).

[0072] In Figure 9(B), black triangles (▲) represent the case where the first building 100 and the second building 200 are constructed adjacent to each other, and white circles (◯) represent the case where only the first building 100 is constructed. From the graph in Figure 9(B), it can be seen that the maximum inter-story displacement of the first building 100, which is an earthquake-resistant structure, is smaller in the response of all stories when the first building 100 and the second building 200 are constructed adjacent to each other (black triangles (▲)) than when the first building 100 is constructed alone (white circles (◯)).

[0073] In Figure 9(D), the black triangles (▲) represent the case where the first building 100 and the second building 200 are constructed adjacent to each other, and the white circles (◯) represent the case where only the second building 200 is constructed. From the graph in Figure 9(D), it can be seen that the maximum inter-story displacement of the second building 200, which is a vibration-controlled building, is slightly larger when the first building 100 and the second building 200 are constructed adjacent to each other (black triangles (▲)) than when the second building 200 is constructed alone (white circles (◯)), but there is almost no difference between the two.

[0074] (Discussion of results) Next, we consider the results of the numerical analysis.

[0075] In the comparative adjacent building structure 55 in which no underground space portion 300 is formed, the first building 100 with earthquake-resistant structure and low damping has almost no change in the amplitude of the transfer function and the maximum inter-story displacement even when the second building 200 with vibration-control structure and high damping is constructed adjacent to it.

[0076] In contrast, in the adjacent building structure 50 of this embodiment in which an underground space section 300 is formed, the first building 100, which has an earthquake-resistant structure and low damping, is constructed adjacent to the second building 200, which has a vibration-control structure and high damping, thereby reducing the amplitude of the transfer function and the maximum inter-story displacement.

[0077] From these results, it was confirmed that by forming an underground space 300 in the ground 10, the second building 200, which has a vibration-control structure and is equipped with a vibration-control damper 90, reacts to the rocking behavior of the first building 100, which has an earthquake-resistant structure and is not equipped with a vibration-control device, and absorbs vibration energy on behalf of the first building 100, thereby reducing the response of the first building 100.

[0078] In the comparative adjacent building structure 55, the amplitude of the transfer function and the maximum inter-story displacement are slightly larger when the first building 100 is constructed adjacent to the second building 200 than when the first building 100 is constructed alone. The following two reasons are considered to be the reasons for this.

[0079] 1. When the distance between adjacent buildings is narrow, the rocking behavior of the foundations of both buildings is constrained by the ground between the buildings (in the comparative example, the ground between the first underground exterior wall 120A and the second underground exterior wall 220A), reducing the effect of ground damping.

[0080] 2. When an earthquake force acts on one building, the force transmitted to the other building will have not only a rotational component but also a horizontal component.

[0081] In addition, in the adjacent building structure 50 of this embodiment, the second building 200 has a slightly larger maximum story displacement. This is because the second building 200 absorbs the vibration energy of the first building 100, which is thought to result in a slightly larger shaking.

[0082] <Modification> Next, an adjacent building structure of a modified example of this embodiment will be described. The only difference from the adjacent building structure 50 of the above embodiment (see FIG. 1) is the underground space portion.

[0083] [First Modification] The underground space portion 310 of the adjacent building structure 51 of the first modified example shown in Figure 2 is formed by removing the ground 10 from the first foundation bottom 150A and the second foundation bottom 250A between the opposing first underground outer wall 120A of the first basement floor 120 of the first building 100 and the second underground outer wall 220A of the second basement floor 220 of the second building 200 to the ground surface 10A. The underground space portion 310 exposes the opposing first underground outer wall 120A and the second underground outer wall 220A from the first foundation bottom 150A of the first spread foundation 150 and the second foundation bottom 250A of the second spread foundation 250 to the ground surface 10A.

[0084] [Second Modification] The underground space portion 320 of the adjacent building structure 52 of the second modified example shown in Figure 3 is composed of an underground space portion 310 and an underground space portion 322. The underground space portion 310 is the same as that of the first modified example, so a description thereof will be omitted.

[0085] The underground space portion 322 is formed by removing the ground 10 from the first foundation bottom 150A and the second foundation bottom 250A on the Y-direction outer sides of the first underground outer wall 120C (the underground outer wall on the opposite side from the adjacent side) of the first building 100 and the second underground outer wall 220C (the underground outer wall on the opposite side from the adjacent side) of the second building 200 to the ground surface 10A. The underground space portion 322 exposes the first underground outer wall 120C and the second underground outer wall 220C from the first foundation bottom 150A and the second foundation bottom 250A to the ground surface 10A.

[0086] [Third Modification] The underground space portion 330 of the adjacent building structure 53 of the third modified example shown in Fig. 4 is formed by removing the ground 10 from the second foundation bottom 250A to the ground surface 10A around the second basement floor 220 of the second building 200. The underground space portion 330 exposes the second underground outer walls 220A, 220B, 220C, 220D and the first underground outer wall 120A from the second foundation bottom 250A to the ground surface 10A.

[0087] [Fourth Modification] 5 is formed by removing the ground 10 from the first foundation bottom 150A to the ground surface 10A around the first basement floor 120 of the first building 100. The underground space 340 exposes the first underground outer walls 120A, 120B, 120C, 120D and the second underground outer wall 220A from the first foundation bottom 150A to the ground surface 10A.

[0088] [Numerical analysis results of deformation] For the adjacent building structure 51 of the first modified example (see Fig. 2) and the adjacent building structure 52 of the second modified example (see Fig. 3), a numerical analysis similar to that for the adjacent building structure 50 of the above embodiment (see Fig. 1) was performed. Fig. 11 shows the results of the numerical analysis for the adjacent building structure 51 of the first modified example in Fig. 2, and Fig. 12 shows the results of the numerical analysis for the adjacent building structure 52 of the second modified example in Fig. 3. From these graphs, it can be seen that the amplitude of the transfer function and the maximum inter-story displacement are reduced when the first building 100, which has an earthquake-resistant structure and low damping, is constructed adjacent to the second building 200, which has a vibration-control structure and high damping.

[0089] The adjacent building structure 52 of the second modified example is likely to be applied to cases where the first elevations 110B, 110D of the first building 100 and the second elevations 210B, 210D of the second building 200 face the road. In cases where multiple buildings are lined up adjacent to each other to form a block, such as in the center of a large city mentioned above, the short sides of the buildings often face the road, and the application of the second modified example is appropriate.

[0090] Furthermore, the second modified example is also suitable for application to the above-mentioned city block when vibration control effects in the X direction are expected.

[0091] <Other> The present invention is not limited to the above-described embodiment and modifications.

[0092] For example, in the above embodiment and modified examples, in addition to the vibration damper 90 that exerts a vibration-damping effect against vibrations in the X direction, a vibration-damping device that exerts a vibration-damping effect against vibrations in the Y direction may be installed in the second building 200.

[0093] Furthermore, for example, in the above embodiment and modified example, the first building 100 is a building with earthquake-resistant structure that is not equipped with a vibration control device, but this is not limited to this. The first building 100 may also be a building with a vibration control structure that has lower damping performance than the second building 200. Specifically, the second building 200 may be a vibration-control building with high damping characteristics (for example, a building equipped with many high-performance dampers), and the first building 100 may be a vibration-control building with low damping characteristics (for example, a building equipped with only a few low-performance dampers).

[0094] Furthermore, the present invention can be embodied in various forms without departing from the spirit and scope of the present invention. A plurality of embodiments and modifications can be implemented in combination as appropriate. [Explanation of symbols]

[0095] 50 Adjacent building structure 51 Adjacent building structure 52 Adjacent building structure 53 Adjacent building structure 54 Adjacent building structure 100 First Building 110 First Ground Floor 110A First elevation 110B First elevation 110C first elevation 110D first elevation 120 First basement floor 120A First basement outer wall 120B First basement outer wall 120C First underground wall 120D First basement outer wall 150 First Direct Foundation 200 Second Building 250 Second Direct Foundation 210 Second Ground Step 210A Second Facade 210B Second Facade 210C Second Facade 210D Second Facade 220 Second Underground Level 220A Second Underground Outer Wall 220B Second Underground Outer Wall 220C Second Underground Outer Wall 220D Second Underground Outer Wall 300 Underground Space Department 310 Underground Space Department 320 Underground Space Department 330 Underground Space Department 340 Underground Space Department

Claims

1. A first building supported by a first spread foundation and having a basement floor; a second building constructed adjacent to and facing the first building, having the same size as the first building and higher damping characteristics than the first building, supported on a second spread foundation provided independently of the first spread foundation, and having a basement floor; an underground space portion in which adjacent and opposing underground exterior walls of the basement floors of the first building and the second building are exposed from the first spread foundation and the second spread foundation to the ground surface; Adjacent building structure with.

2. The underground space also exposes an underground exterior wall on the opposite side to the adjacent side of the first building and the second building.

10. The adjacent building structure of claim 1.

3. The underground space portion exposes underground exterior walls around the entire periphery of the basement floors of the first building and the second building, 3. The adjacent building structure of claim 2.

4. The first building and the second building have elevations with an aspect ratio of building height to building width of 4 or more, The first building and the second building have the same elevation direction. The adjacent building structure according to any one of claims 1 to 3.

5. The first building and the second building have the same or approximately the same natural frequency. The adjacent building structure according to any one of claims 1 to 4.

6. The first building and the second building are not connected by a damper. The adjacent building structure according to any one of claims 1 to 5.

Images