JP2019007335A - Structure for reducing earthquake stress caused on architectural structure - Google Patents

Abstract

To provide a solution, which is not to further enhance the earthquake resistance of architectural structures themselves, but to aim at reducing stress per unit area by increasing to the utmost the area of: a) the outer-surface side of the rising part in the case of lateral-vibration earthquake; b) the bottom-surface side of leveling concrete in the case of vertical-vibration earthquake or epicentral earthquake; and c) the surface of breakwaters and the like, which faces tsunami wave in the case of tsunami.SOLUTION: A structure for reducing earthquake stress caused on architectural structures in this invention is characterized by placing at the bottom of structures a structure which can divide earthquake stress into vertical stress and shear stress.SELECTED DRAWING: Figure 1

Description

  An earthquake stress reduction structure that can reduce the stress received by structures such as buildings and structures and change the direction of the earthquake wave, satisfying both of the two characteristics of earthquake motion that has two characteristics of stress and wave motion. About.

  In general, a building such as a house, a building, or a building is thrown away with concrete and then foundation concrete. Abandoned concrete is almost flat and horizontal.

  The foundation concrete is also a horizontal plane, and the rising part is also a vertical plane. Certainly, the vertical input is considered to be the largest in terms of mechanical force against rolling or pitching. However, considering the force per unit area that receives the seismic force, if the area that receives the input seismic force is increased, the stress per unit area that the building receives is reduced by the increase. Therefore, it can be determined that the area to be received should be increased in order to reduce such stress.

  However, there are the following restrictions. In other words, earthquakes also have wave characteristics, and as shown by Snell's law, the refractive index of the medium, such as soil, concrete, and atmosphere, that forms the substructure of the building, excluding the vertical input of seismic force The direction of the seismic wave changes due to, and in some cases, it is totally reflected like an optical fiber, does not go out into the atmosphere from the concrete foundation, is accumulated and amplified, and continues to be reflected and amplified in the concrete and the building. In some cases, it may lead to major damage to buildings including rising concrete. Therefore, it is essential not only to expand the area of the building that receives the seismic force, but also to ensure that the angle between the normal and the wave direction does not exceed the critical angle. It is indispensable to have some structure narrowed down to a range where total reflection does not occur.

  Furthermore, not only for buildings but also for breakwaters, embankments, and ship mooring revetment wall structures, increasing the area of the surface subjected to the tsunami affects the refractive index of the seawater, concrete, soil, seawater, or air of the constituent materials. Since the direction of the seismic wave is also different, there is a case where total reflection occurs in the same manner. Similarly, a structure to be considered is indispensable.

  In the case of a rolling earthquake, depending on the conditions of the site, the location of the building may not be arranged so that the rising part is perpendicular to the direction of the seismic wave. Due to the shape of the bay, the breakwater is not always perpendicular to the wave direction. In such a case, as described above, the basic idea should be maintained and dealt with. When seismic waves are incident obliquely, total reflection tends to occur, and special structural design is indispensable.

  Furthermore, although the new seismic standard enforced in 1981 uses only the maximum acceleration of the seismometer as a design standard, in reality, the wave of acceleration below that continues for a certain period. Thereby, there can even be a progression from partial destruction to even greater destruction. In fact, in the Kumamoto Earthquake, it has been reported that houses built according to the new earthquake resistance standards were completely destroyed. For this reason, the present invention should be effective not only for reducing the seismic force corresponding to one maximum acceleration, but also for many acceleration fluctuations within the duration of all earthquake occurrences.

  Here, looking at the types of earthquakes, it can be broadly divided into roll and pitch earthquakes caused by trench-type earthquakes, and pitch earthquakes caused by direct earthquakes that occur in Japan. Regarding the latter, the current seismometers are not able to grasp the fracture energy for the pitching earthquakes seen in the Niigata Earthquake and the Great Hanshin-Awaji Earthquake, and seismologists will continue to improve their research in this field. Some say it is necessary.

  On the other hand, as a countermeasure against rolling earthquakes, a new seismic standard based on mechanical analysis using shear stress was established, reflecting the analysis and results of past failure conditions. As for pitching earthquakes, the Nuclear Safety Commission has determined that pitching is less than half of rolling based on analysis of the Hyogoken-Nanbu Earthquake. However, as far as the data is concerned, it cannot be said that it is less than half.

  However, as already mentioned, in the Kumamoto District Earthquake, even buildings based on the new earthquake resistance standards have collapsed. Also, mechanical analysis has not been performed for pitching and direct type earthquakes. Osaka City University and other organizations have assumed that the Hanshin-Awaji Earthquake is a direct type earthquake and is caused by shock waves. He gives a new view of the earthquake.

  The Japan Society of Civil Engineers, which handles ground structures such as bridges and dams, civil engineering structures such as quays and embankments, and various basic structures such as bridges and tanks, `` Second Proposal on Seismic Standards for Civil Structures '' (1996) It was proposed in January), but there are many issues and it seems that progress is not progressing.

  It is said that there are 2000 active faults in Japan, but there may be more active faults.

Therefore, recently, the frequency of earthquakes is high, and aftershocks of the earthquake frequently occur in the Kumamoto earthquake. In this situation, it is also important to keep conscious of the following matters when taking countermeasures.
i) First, grasp specific examples of past earthquakes, especially because the rolls will be mainly of trench type, which is due to the approximate direction and magnitude of rolls of earthquakes and active faults. If there is an earthquake, it is also necessary to know the extent.
ii) It is also necessary to understand the soil quality. In particular, it is necessary to strengthen the earthquake resistance measures of the building itself, but the foundation of the building and its rising part will be strengthened, and response technology will be important, and this will be emphasized in terms of both strength and vibration.

  Patent Document 1 relates to an embankment having a wave-dissipating function, in which the normal line of the embankment has a wave shape. When the waves hit and hit the embankment, the embankment is curved, so the waves collide with each other and have an effect of having a wave-dissipating effect.

  Since details are not described at all in Patent Document 1, there are many unclear points. Therefore, an appropriate assumption is considered from the fact that it is a dike.

  First of all, the idea is that the levee has a wave shape, and therefore waves collide with each other. However, as far as it can be seen in FIG. In FIG. 13, it is assumed that a wave hits the dike at an angle of 60 degrees, FIG. 13 (a) shows a reflected wave from a slope with the same slope, and FIG. 13 (b) shows a slope with adjacent slopes. However, none of them is in the opposite direction of the incident wave, and does not contribute to the reduction of the incident wave. Therefore, it was decided to clarify how much the collision actually occurred by calculating the reflectance.

1 Reflectance when a wave hits a dike perpendicularly is as follows. The reflectance is Ir.
N ₀ : The refractive index of the incident side medium (water) is 1.333, N ₁ : The refractive index of the dike concrete is 1.54.
Ir = (N ₀ −N ₁ ) ² / (N ₀ + N ₁ ) ² = 0.0052
This means that the angle between the incidence and the normal is zero, and in this case the reflectivity is only 0.5%.

When two waves are obliquely incident, the reflectance is different between the S-polarized light and the P-polarized light, so that calculation is performed using two equations.
Irp = (n ₀ cos θt−n ₁ cos θ ₀ ) ² / (n ₀ cos θt + n ₁ cos θ ₀ ) ²
Irs = (n ₀ cos θ ₀ −n ₁ cos θt) ² / (n ₀ cos θ ₀ + n ₁ cos θt) ²
Here, θ ₀ represents the incident angle, and θt represents the refraction angle. The reflected wave angle is the same as the incident angle through the normal.

2-1 Next, the calculation result when the incident angle with respect to the normal is 30 degrees, that is, 60 degrees with respect to the bank is shown. The refraction angle is 25.5 degrees.
Irp = 0.026 0.26%
Irs = 0.0002 0.02%

2-2 Next, a calculation result is shown for a case where the normal and the incident angle are 60 degrees, that is, the wave is incident on the dike at 30 degrees. The refraction angle is 48.5 degrees.
Irp = 0.0046 0.46%
Irs = 0.044 4.4%
Transmittance = 1-reflectivity

  These calculations require a refractive index, but it is unclear what material is used, and it is not clear at all whether it is a tetrapod-like object with voids piled up in a wave shape or otherwise. The refractive index was calculated from the material composition of the present invention. As a result, 95% of the wave was transmitted and the reflection was only 5% at maximum. Therefore, in Patent Document 1, the reflectivity is low, and the collision effect between waves cannot be expected, and it cannot be expected from the wave directionality.

  Furthermore, at the position where the wave stress is in contact with the shaded area (in the patent document, the slope of the levee), the X axis represents the shear stress and the Y axis represents the normal stress, but the shear stress is along the concrete. It is easy to flow smoothly and without resistance, flow into soil that is easy to move in contact with concrete, change to kinetic energy, and reduce stress. However, Patent Document 1 expresses that “the bank is provided with slits in claim 3”, but it is difficult to say that the shear stress is easily reduced.

  Non-Patent Document 1 is a structure that is installed offshore for the purpose of creating a calm sea area near the coast, and its function is to control waves and sand drift, etc., and it has permeability from the viewpoint of water quality and environmental conservation. Desirably, various studies have been made heretofore, but they did not show good wave-dissipating performance. This is a paper that developed a double-parapet type breakwater that combines two parapet-shaped permeable curved walls and has an opening in front of the dam body that leads to the water reclaiming section.

  The reason why this is cited as non-patent literature is as follows. The permeable curved wall has at least a quarter-shaped curved surface of a circle, and its upper end is a vertical plane. The shock wave pressure has a dimensionless average wave pressure intensity of 2 to 6 acting on the conventional upright wall, whereas the dimensionless average wave pressure intensity of the curved wall is 2, which is 2 to 6 in the case of the conventional upright wall. In comparison, the value is considerably low. The author concludes that the reason for this is that the wave pressure strength can be reduced by the wave rising up due to the curved shape of the parapet.

  However, seismic force is regarded as stress per unit area, and this reduction increases the area of the surface that receives the seismic force, that is, lowers the stress and the earthquake has both stress and wave characteristics. The idea of “the wave pressure intensity can be reduced by the wave creeping upward” in Document 1 is an error. In other words, the kinetic energy of the wave that is approaching has only changed to the potential energy corresponding to the amount of the wave. In short, the conclusion is that the area is larger than the vertical wall and the stress is only reduced.

  In addition, the impact of earthquakes on structures includes uneven settlement due to liquefaction. According to Non-Technical Document 2, the mechanism of liquefaction is sandy soil, soil with a high water content, and water and soil separated by relatively gentle vibration (about 300 gal). Due to the specific gravity, the water has springed up or erupted on the surface, and this causes the buildings to sink unevenly. Conventional general measures are as follows: a) Strengthening of soil by uniform mixing with cement and other solidifying agents, b) consolidation of ground, c) reduction of water level by pumping up groundwater level, and d) structure. A grid-like wall is created in the ground, and the seismic force transmitted to the structure is cut off and reduced. E) Stakes are laid from the foundation to the non-liquefied layer to suppress uneven settlement. However, these measures are difficult to ensure due to the quality and depth of the soil, and the costs are high.Therefore, no measures have been established at this time, and various methods have been proposed and the warranty period Seems to be limited to 10 years. Even if such measures are taken, if the subsidence does not occur, it is necessary to take measures to restore the current state by dismantling the structure or by jacking up.

  In particular, the above countermeasure d) will be described in more detail. Columnar solidified walls are created in the ground around the building, and these are arranged in a grid, creating a grid-like four-sided wall and shearing the ground. It prevents deformation and reduces earthquake vibration in the wall and suppresses liquefaction. 1) It is difficult to assume the scale of the earthquake that will occur in the future, and the setting of the lattice spacing to suppress the vibration in the wall is decided. Difficult, D 2) Earthquakes have both dynamics and waves, and as described above, the reflectivity of waves is low even if they are perpendicularly incident on the wall surface. 3) Furthermore, as described above, in the case of oblique incidence, there is a risk of total reflection due to the angle of incidence. 4) In addition, it is suitable for the shear deformation of the ground. Because it is narrowed down, it is not a measure against longitudinal vibration corresponding to vertical earthquakes and direct earthquakes, etc. There are drawbacks.

JP-A-8-92937

Yoshihiro Tanaka, Shinzo Furukawa, Takaaki Nakamura “Development of Double Parapet Type Breakwater”, Coastal Engineering, Vol.36, 1989, p.608 "Examination of liquefaction countermeasure construction method document-6", www.city.asahi.lg.jp/section/toshi/files/2013-0911-1529.pdf

  Now, as described, the opinions of the government and universities differ about the way earthquake countermeasures should be, and the rationale is not clear. Whether it is a roll, pitch, or direct earthquake, the first issue is not a measure to further improve the earthquake resistance of the building itself. A) For a roll earthquake, B) To reduce the stress per unit area by increasing the area of the surface that receives the tsunami, such as the breakwater, on the lower surface side of the discarded concrete for pitching earthquakes and direct earthquakes, and c) for the tsunami. . Specifically, for example, the cross-sectional shape is a mountain shape or an uneven surface, and the entire portion, that is, three-dimensionally, is attached (FIGS. 1 and 2). In this case, there is a problem that it is necessary to set what shape is a preferable shape including the following conditions.

  The second problem is that the essence of an earthquake has both dynamics and waves. Based on this, countermeasures should be taken. In particular, when a wave passes through different adjacent media, the direction of the wave changes according to Snell's law and total reflection occurs when the medium travels from the high side to the low side, resulting in no expected attenuation. Promote damage and destruction of buildings. Therefore, even if the first problem is solved, there is a problem that the second problem must be cleared.

  The third problem is that the strength of a building is calculated for the highest acceleration (measured by a seismometer) in the new earthquake resistance standard. In this case, the problem is whether there is a guarantee that the building will not be damaged at all with respect to vibration below the next highest acceleration. If it is damaged to some extent, it is estimated that the damage will proceed even with the second and subsequent accelerations. In such a case, if the first problem and the second problem are solved, there is a problem explaining that the seismic force corresponding to the continuously transmitted acceleration change can be reduced. If a significant stress reduction can be obtained even if a direct answer cannot be made, it may be considered that this is proved.

  The fourth issue is based on the premise that the waves hit the abandoned concrete, the rising part, or the breakwater in the issues 1 to 3, but the fourth issue is an issue to determine what happens in the case of diagonal input. is there.

  The fifth problem is ascertaining whether it is possible to further reduce the stress.

  The sixth problem is whether it can cope with the problem of liquefaction.

  Therefore, first, the pitch earthquake will be described, and then the roll earthquake and tsunami will be described. The reason is that in the latter case, the direction of the force received is merely 90 degrees off. As a method to reduce the stress due to the seismic force received by the structure, for example, in abandoned concrete or foundation concrete, the seismic wave is incident vertically, and the area of the foundation part to be received should be expanded to reduce the strength per unit area. become.

  Also, it is assumed that a rolling earthquake or tsunami is incident horizontally on a concrete riser or a breakwater. Also in this case, in order to reduce the stress received in the horizontal direction, the area to be received may be increased.

  For example, as shown in FIG. 1 and FIG. 2, the cross section is formed in a mountain shape or an uneven shape, and the cross sectional shape is arranged in a row like a vine in the field, and reaches the depth. . This structure is most preferably formed in such a state that it is spread over the entire foundation of the structure, that is, not the entire surface. In the following description and drawings, “cross-sectional shape” and “cross-section” are expressed even if “cross-sectional shape” and “cross-section” are not clearly described.

  FIG. 1 is a mountain shape that is connected at the bottom, spreads to the left and right, and extends to the entire depth. For example, assuming that a triangular ridge of a field is formed over the entire site of a building or the like. It will be good. Looking at FIG. 1, the half-mountain has a triangular shape. Although not shown in FIG. 1 above these shapes, generally discarded concrete is provided, and further, a concrete foundation and a rising portion are provided.

  FIG. 2 shows a concave shape among the examples of the concavo-convex shape, which is similarly formed three-dimensionally. As described above, abandoned concrete or concrete foundation is provided on the concave surface of FIG.

  Next, as shown in Fig. 3, when a wave of an earthquake or surface wave hits a triangular side, the normal setting position is determined at that position, the stress components are divided into X and Y components, and the respective stresses are plotted. Is the product of the trigonometric function shown in. Here, the stress of the wave is indicated as F. The X component is shear stress and the Y component is normal stress.

  In FIG. 3, three types of triangles are written (accurately, they are two-sided, but they can also be regarded as triangles, and may be expressed as such below). The angle between the hatched portion and the base of the inverted triangle is 60 degrees, 45 degrees, and 30 degrees from the top of FIG. The stress F and X components of the wave coming from the vertical are along the diagonal line of the triangle and easily change to kinetic energy, including the contacting soil, but the Y component enters the concrete and causes vibration and destruction. Therefore, the smaller the value of the Y component, the greater the vibration suppression effect. When the angle is changed and the change is seen, the value of the Y component is halved to 1/2 in the range of FIG. 3 when the angle is 60 degrees. That is, when the angle is 60 degrees, the reduction effect is 50%. Moreover, when the angle is 45 degrees, the reduction effect is about 30%. It can be seen that the reduction rate decreases as the angle decreases.

  On the other hand, in the semicircular shape shown in FIG. 4, when the latter is divided by the former by the length 2r entering from the lower part with respect to the length 2πr of the circumferential part, 1 / π is obtained by averaging 1 / π = 0.318 times, That is, the reduction effect is 68.15%, and it can be said that the incident stress F is greatly reduced.

  3 and 4, the cross section is described, but there is actually a depth, and it can be said that the reduction rate of F per unit area. The first problem can be understood that the stress on the receiving surface can be greatly reduced by enlarging the receiving area. Here, F is the stress of the seismic wave.

  The JMA seismic intensity scale is said to be empirically correlated with the Hiraoka acceleration. There is a theory that there is no, but if it is reduced to about 1/2, it can be said that a significant effect is recognized. In the case of rolls and breakwaters, the direction of the waves is different from the case described above, and since it is horizontal, it can be said that the above logic applies as it is when rotated 90 degrees.

  Next, as for the second issue, after the earthquake ground motion gives a vibration to the structure, the surrounding soil, air and atmosphere will be “distance attenuated”, that is, it will attenuate with the distance. There is a problem of whether to escape to the air and the atmosphere. For this purpose, it is necessary that total reflection does not occur in the process of reaching the atmosphere via various media. FIG. 5A shows a state in which the angle between the inclined portion and the base of the inverted triangular triangle shown above is 60 degrees, and a wave of wave stress F is incident on this inclined portion. FIG. 4B shows a state in which the angle is 45 degrees and a seismic wave is incident on the inclined portion. Here, the state where the incident F wave escapes to the atmosphere is illustrated.

First, FIG. 5A will be described. The line drawn at right angles to the diagonal line is the normal, and the path of the F wave through the atmosphere reveals the refraction of the F wave. Snell's formula is given by
sinθ ₁ × n ₁ = sinθ ₂ × n ₂
Here, θ ₁ is an incident angle to the medium 1, θ ₂ is a refraction angle to the medium 2, n ₁ is a refractive index of the medium 1, and n ₂ is a refractive index of the medium 2. In addition, the incident stress was assumed to escape from the soil through the concrete to the atmosphere, and the refractive index of the soil, the refractive index of the concrete, and the refractive index of the atmosphere were calculated as 1.5, 1.54, and 1.0, respectively.

  In this triangle, the angle between the base and the shaded part is an inverted triangle of 60 degrees, and the line perpendicular to the shaded part is the normal line. The wave of F is the shape which hits the shaded part perpendicularly from under the soil. The incident angle and refraction angle are determined by Snell's law by the angle between the F wave direction and the normal.

Then, the incident angle and refraction angle of the F wave incident on the shaded area are as follows.
1.5 x sin 60 = 1.54 x sin θ ₁ , so θ ₁ = 57.5
That is, the refraction angle θ ₁ entering the concrete from the soil is refracted to 57.5 degrees.

Next, the F wave refracted at 57.5 degrees reaches the top of the concrete, that is, the interface with air. This incident angle is 60-57.5 = 2.5 degrees. Similarly, Applying Snell's formula, (here, the theta ₂ represent. The angle of refraction to the atmosphere) 1.54 × sin2.5 = 1 × sinθ 2 by, theta ₂ is 4 degrees. Therefore, there is no total reflection.

Next, the figure of FIG.5 (b) is an inverted triangle whose angle | corner of a base part and a shaded part is 45 degree | times, and the wave of F enters perpendicular | vertical to a base.
Then, similarly, the calculation is as follows.
The _{1.5 × sin45 = 1 × sinθ 3} , θ 3 = 43.5
Like the left side of the figure, wave F is advanced to the interface of the concrete and the atmosphere, wherein, applying Snell's equation, by _{1.54 × sin1.5 = 1 × sinθ 4} , θ 4 is 2 degrees. Incidentally, 45 degrees-43.5 degrees = 1.5 degrees. Therefore, there is no total reflection.

Note that total reflection occurs depending on the incident angle when two media having different refractive indices are refracted from a higher refractive index to a lower refractive index. Now, when the medium is concrete, the refractive index is 1.54, and the wave goes out to the atmosphere (refractive index 1), the following equation holds.
1.54 × sinθ = 1 × sin90
Thus, total reflection occurs when the incident angle θ is 40.5 degrees or more.

  Next, it was shown that the concave shape was the same as in FIG. In FIG. 6, below the semicircle is soil, the upper part is concrete, and the upper end surface of the concrete is air. Then, it is the same as Yamagata, but the difference is that it is only different in shape and that the normal is perpendicular to the tangent of the circle. The wave of F is assumed to be incident vertically from below, and from the left side of FIG. 6, the angles of F and the normal are 80 degrees, 60 degrees and 10 degrees. The refractive index of the medium is the same using the Snell equation as in FIG.

For angles of incidence and refraction angle from the soil to the concrete case 1 normal and the incident angle is 80 degrees, the _{1.5 × sin80 = 1.54 × sinθ 1} , θ 1 = 67.1
Then, the angle of refraction and angle of incidence from the concrete to the atmosphere, because the input angle of the upper end portion of the concrete is 80-67.1 = 12.9, by _{1.54 × sin12.9 = 1 × sinθ 2} , refraction angle theta ₂ = 20.2

About incidence and refraction angle from the soil to the concrete case 2 normal and the incident angle is 60 degrees, the _{1.5 × sin60 = 1.54 × sinθ 3} , θ 3 = 57.5
Next, with respect to the incident angle and the refraction angle from the concrete to the atmosphere, the input angle at the upper end of the concrete is 60-57.5 = 2.5, so that the refraction angle θ ₄ = 4.3 by 1.54 × sin2.5 = 1 × sinθ _4.
About 3 normal and the incident angle of the incident angle and the refractive index of the concrete from the same soil for the case of 10 degrees, the _{1.5 × sin10 = 1 × sinθ 5} , θ 5 = 9.54
Then, the angle of incidence and the refractive index from the concrete to the atmosphere, because the input angle of the upper end portion of the concrete is 10-9.54 = 0.46 degrees, by _{1.54 × sin0.46 = 1 × sinθ 6} , θ 6 = 0.7

  As described above, total reflection is not performed for all.

  From the above example, one conclusion is that the seismic wave is perpendicularly incident on the bottom surface of the concrete, and the F wave that escapes to the atmosphere is flat on the top surface of the concrete, so the normal direction is vertical. Therefore, when a medium having a high refractive index is a small medium, that is, a seismic wave escapes to the atmosphere, total reflection does not occur. Therefore, it is considered that the third problem has been solved because the exemplary chevron or uneven shape is attached to the lower end surface of the concrete to significantly reduce stress and total reflection does not occur.

  The first to third issues have been discussed as the vertical input of earthquake stress to the structure. The fourth problem is to explain the case where the wave of stress F is input obliquely, and if there is an irrationality, discuss the countermeasures.

  Next, the fourth problem will be described. That is, the case where the input wave is not vertical but oblique input will be described with reference to FIG. In particular, this case is a direct earthquake, and it should be considered as an oblique input at a position far away from the position where the large deviation occurred, even if it is a direct earthquake. Furthermore, in the case of rolling, the rising part from the foundation of the building may be forced to take an oblique input with respect to the rising part of the building as seen from past examples depending on the shape of the site Occurs (for example, FIG. 9).

  In the case of a tsunami, depending on the shape of the bay, there may be cases where the tsunami is not always input vertically to the breakwater or quay. In such a case, in the case of oblique input, in the case of oblique input, it will be ignored because the load is small, but in the case of waves, it will be totally reflected and accumulated without going out of the system, causing damage to the building. Wake up and the effect is great.

  This will be described with reference to FIG. FIG. 7 is a cross-sectional view of a general basic structure of a building composed of soil, concrete and air with different media. In addition, it is a figure that can be recognized as a substructure of a breakwater if there is seawater and a place where the soil is shifted 90 degrees and there is concrete and the place where the atmosphere is described is left as the atmosphere. In any case, a partial cross-sectional view when the stress of the seismic wave is inputted obliquely to the foundation part of the building or the breakwater is shown.

  FIG. 7 shows a state in which the seismic wave stress is refracted from the top surface of the concrete to the atmosphere in order from the right by selecting three factors of 30, 40, and 50 degrees as the angle at which the stress from the soil is incident on the foundation. It can be seen that total reflection occurs when the incident angle is 30 or 40 degrees. On the other hand, total reflection does not occur at 50 degrees or more. However, in the case of the former two, since it is total reflection, the stress does not go out of the system, leading to destruction of the structure. In particular, it can be said that the S wave causes a more serious result because it does not propagate to a medium such as air, water or seawater. As a precaution, unlike the S wave, the P wave has the character of propagating to these media and has a low influence.

  Therefore, a countermeasure method is shown in FIG. In FIG. 8, it was judged that the incident angle shown in FIG. A specific method will be described first in the case where the incident angle of the seismic wave in FIG. It should be noted that the incident angle is 30 and 40 degrees, resulting in total reflection. FIG. 8 is an equilateral triangle having a mountain shape and an angle between the horizontal portion and the shaded portion of 60 degrees, which has already been illustrated and described.

  Attached with a shape such that the angle between the incident angle or the refraction angle and the normal is zero or close to zero, here, the cross-section is a regular triangle, and this is attached to the top surface of the concrete, that is, It was found that measures can be taken by mounting on the refractive side. Here, the word attached has two meanings. That is, one means that the surface shape itself has a specific structure and an integrated shape structure, and the other is a shape structure that attaches or attaches the specific shape itself to the surface in a planar structure. Henceforth, it is described as a shape structure including both meanings. According to Snell's law, if the angle between the normal and the refraction is zero, or if the angle is close to zero, total reflection is not performed. The angle at which total reflection occurs has already been described.

  In FIG. 8B, the incident angle of the seismic wave is 40 degrees, and in FIG. As a result, the angle between the refraction angle and the normal is several degrees, and total reflection does not occur. Therefore, no matter how many times the incident angle is estimated strictly, in the case of a tsunami etc., the incident angle is generally constant at this place, depending on the magnitude of the earthquake, water level, bay shape, high tide time, etc. If it is considered that it has a certain width, when comparing the left and right views of FIG. 8, it is determined that it is appropriate to consider that total reflection does not occur even if the incident angle changes slightly. It can be understood from FIG. 8 that it can be used in the case of oblique input together with an attached structure for reducing seismic stress, and is effective in preventing total reflection.

  Also, in FIG. 9, if there is experience of a rolling earthquake incident on the building at an angle of 30 degrees, for example, based on past results, it is described in FIG. 3 and FIG. 4. It is also one method to install a new structure perpendicular to the direction of the stress in the mountain shape or the uneven shape. In this case, it is effective not only for buildings but also for quays and breakwaters. In addition, the continuous mountain shape shown perpendicularly to the seismic wave F in FIG. 9 indicates a structural shape.

  Next, the fifth problem is whether or not there is a further method for greatly reducing seismic stress. If the input seismic stress hits a different boundary surface of the medium, when the perpendicular is drawn to the boundary surface, this becomes a normal, and becomes a stress and a normal stress. Then, these stresses are products of trigonometric functions and are less than the initial stresses. The extent of this reduction varies depending on the shape. This has already been explained in FIGS. From the viewpoint of workability and the like, when a normal stress is input to a 60 ° equilateral triangle with the base as a horizontal portion, the normal stress is 1/2 × incident stress. If a semicircle is used among the irregular shapes, it becomes 1 / π. Therefore, a considerable reduction effect is obtained. In addition, in the case of the semicircular shape, it can be seen from FIG. 6 that the direction of the stress is dispersed for each normal.

  Therefore, as a further reduction method, if one of the above reduction methods is used and the shape structure is a double structure, the reduction rate is 75% for the equilateral triangular mountain shape, and the reduction rate for the semicircular shape. Will be 90%. Moreover, the direction of stress is distributed as shown in FIG. In the triangular shape structure, the reduction rate is slightly lower than the semicircular shape, but a triple structure may be used. In this case, even if the thickness of the concrete is reduced, the reduction rate is improved because there is no element of thickness in Snell's law. In particular, the stress of direct earthquakes has not been clarified so far. Therefore, a three-stage product or a four-stage product of the shape structure can be used to further reduce the reduction rate.

  Since a direct earthquake should be judged to have a higher stress due to an earthquake than a trench earthquake, a multi-stage structure is preferred. The multi-stage structure integrates each structure, but the boundary is not a void or concrete, but a layer of soil or other medium is indispensable, several millimeters to several centimeters or more, and several centimeters is appropriate for soil It is.

  Next, the sixth problem will be described. Arranged to form a box-shaped body consisting of four wall surfaces and a bottom surface near the foundation (possibly discarded concrete) and the rising part with respect to the structure, and the shape structure on the outside of the box-shaped body A body can be attached or installed, and the stress of an earthquake can be divided into a vertical stress and a shear stress. The cross-sectional shape is a triangle or other irregular shape such as a circle. The basic idea of attachment or installation is kept as it is, and one or more shape structures are provided, and the reduction rate is shown to the power, and the application of Snell's law for that purpose is adjacent. At the boundary, if a medium having a refractive index that is not equivalent is provided, the installation range of the shape structure from the structure is also set, and even if it is subjected to stress at the bottom of the box-like body, even if it is pitched, Apply the theory of the present invention as it is Ur. Therefore, the reduction in liquefaction is merely a difference in target items, and they are all the same.

  However, there may be cases where liquefaction occurs in the soil reaching the basement below the bottom. In such a case, even if the structure reduces the seismic stress, there is a possibility that uneven settlement or uniform settlement may occur, and as a countermeasure, pile driving up to the non-liquefied layer is necessary.

FIG. 1 is a conceptual diagram of a lower structure of a structure in which a grounding portion has a mountain-shaped cross-sectional shape. FIG. 2 is a conceptual diagram of the lower structure of the structure in which the grounding portion has a semicircular cross-sectional shape. FIG. 3 is an explanatory diagram regarding shear stress and normal stress when the substructure of FIG. 1 receives earthquake stress. FIG. 4 is an explanatory diagram relating to shear stress and normal stress when the lower structure of FIG. 2 receives earthquake stress. FIG. 5 is an explanatory diagram regarding a state in which an earthquake wave is input from the ground side to the lower structure of FIG. 1 and the wave is refracted by Snell's law. FIG. 6 is an explanatory diagram regarding a state in which an earthquake wave is input to the lower structure of FIG. 2 from the ground side and the wave is refracted by Snell's law. FIG. 7 is an explanatory diagram regarding the behavior of refraction according to Snell's law with three types of wave input angles. FIG. 8 is an explanatory diagram related to a countermeasure for the total reflection in FIG. FIG. 9 is an explanatory diagram relating to a countermeasure when a rolling earthquake is input obliquely by 30 degrees with respect to a building. FIG. 10 is an explanatory diagram relating to various forms of the lower structure of the structure. FIG. 11 is an explanatory diagram regarding still another modification of the lower structure of the structure. FIG. 12 is an explanatory diagram relating to an example in which a box-like body is provided as a lower structure of a structure, and a shape structure is provided on the outer surface of the box-like body. FIG. 13 is an explanatory diagram regarding a case where a wave is incident on the bank of Patent Document 1. FIG.

  Although it has been recognized academically that earthquake waves have both dynamic and wave properties, in reality, countermeasures are implemented by only one of them. is necessary. Therefore, the most serious damage is caused by subduction-type pitching earthquakes and direct-type pitching earthquakes that are perpendicular to the foundation of the building. An earthquake or the like is a wave perpendicular to a rising part of a building, a breakwater or a quay.

  Therefore, seismic waves incident on different media can be divided into normal lines, vertical stresses, and shear stresses by entering into a linear structure with a gradient or a curved structure. That is where material mechanics is taught. Therefore, the present invention is designed to solve the problem and to take measures based on the normal stress and the shear stress. Here, the shape of such a shape structure is (1) representatively representing a cross-sectional shape, for example, a triangle, a triangle, a quadrangle, a rhombus, a further square, a semicircle, a circle, an ellipse, etc. The structure is three-dimensionally extended in the depth, and these may have the same or different shapes. Furthermore, (2) as a three-dimensional simple substance, various pyramids, various cones, various spheres, ellipsoids, and polyhedrons, the structure attached in three dimensions, the shapes of (1) and (2) are the same Or it may be a combination of different shapes.

  The point is that the stress can be divided into a normal stress and a shear stress, and the shape may be a shape having one or more sides for a cross-sectional shape and one or more surfaces for a three-dimensional simple substance. What is necessary is just to install or attach so that the direction of stress may be divided into a normal stress and a shear stress by hitting this side or surface. However, it should be noted that when the seismic wave is incident perpendicularly with the plane part of the shape structure such as a regular hexahedron or a rectangular parallelepiped down, the normal and incident wave angles become zero, and the normal and shear stresses Therefore, as shown in the example of the rhombus in FIG. If analyzed in this way, the shape structure is installed or attached so that it has one or more sides and surfaces that are divided into normal stress and shear stress as described above rather than the shape of the shape structure itself. You can do it. In addition, when one right triangle is selected as the cross-sectional shape, if this single shape is used, one side of the site must be deeply drilled. Not even realistic. Therefore, it may be installed or attached in a realistic size in consideration of workability and the like.

  As a typical shape, the cross section has four deformations including a triangle, a triangle, and a rhombus, the cross section is a semicircular or circular uneven surface shape, and the shape is in the depth direction. These shapes may be combined with each other, or may be a combination of these shapes or vice versa, and at least these shapes should be included. Here, “representative” means the economy and workability, and the adoption of other shapes does not mean meaningless.

  More specifically, as described above, the shape is composed of sides, and when a stress is applied to any one of the sides, the shape can be decomposed into shear stress and normal stress. For example, if it is classified and described as being representative and easy to stack in multiple stages, one is a cross-sectional shape that is a triangle, triangle, quadrangle, pentagon, etc. , A circle, an ellipse, and a shape that is three-dimensionally connected in the length direction like a ridge, and two of them are a sphere, a triangular pyramid, a quadrangular pyramid, a regular tetrahedron, an octahedron, etc. The reverse combination can be used effectively. In addition, when stacking in multiple stages, the contact surfaces of the material need to have different refractive indexes. However, the material of the shape structure may be made of concrete, metal such as aluminum, or resin. Furthermore, especially when the shape structure is made of concrete, even if the edges or rounded portions are somewhat chipped or broken, the proportion of the total area is small, the degree of influence is low, , The degree of influence gets worse. Although the size and size of each shape structure have already been described, various means of mechanization can be changed by modification or development, and the dimensions are not limited. FIG. 10 shows a typical shape of a shape structure having a constant cross-section and three-dimensionally connected in the length direction. A single shape and two units of the shape structure are connected to each other. Shown for two stacks. If the shape structure is made of concrete and waste concrete or foundation concrete is used, Snell's law is applied to these interfaces. It is indispensable to cover it with the substance it has, which is not shown in the drawing. Moreover, a structure as shown in FIG. 11 may be used.

  Here, the shear stress is the boundary of the medium in contact, that is, the boundary with the soil, and is easily consumed as the kinetic energy of the soil, so that the contribution to the breakage / destruction of the structure is low. On the other hand, the normal stress becomes the fracture stress of the structure. 3 and 4 as described for normal stress.

  These shape structures are attached to the forefront of the seismic wave. In other words, it is typically attached in a shape that receives the seismic wave first, whether it is a mountain shape or an uneven surface shape. In this case, for example, it may be directly attached to the foundation, rising part, or breakwater of the building, or may be separated. The refraction angle is only slightly different and the degree of influence is small. This is because it is not a force but a wave.

  The material of the shape structure may be a metal material, a resin material, or a concrete material. This is because, although the refraction angle changes when the medium is different, there is essentially no significant change.

  When installing remotely, since it receives seismic stress at the initiative, at least reinforcement according to the conventional design standard, that is, backup is indispensable.

  In terms of cost, it should be made of concrete. As described, for pitch earthquakes, etc., if it is attached directly to the foundation of the building, it may be attached to the underside of the discarded concrete. In this case, in the case of manual labor, the soil is dug so as to have the shape, and the amount of soil is made uniform with a rake shape or the like so as to have the shape so that the amount of the soil is not excessive or insufficient, and the concrete is thrown away. Alternatively, it is also possible to use an agricultural dredge machine that produces field straw. There is also a method in which a concrete (pre) molded body in which one or more of the shape structures are integrated is spread over the entire site on a flat soil and discarded concrete is cast.

  In particular, in order to install and attach to the rising part, etc., one or more groups of shape structures are installed on the surface that receives the earthquake wave, and only the inside of the paired wooden frame is made of wood in advance. A method of removing a wooden frame after solidifying with a bolt and a solid structure having a hole formed therein, and a method of passing a bolt through a PVC pipe to facilitate removal of the bolt may be used. In this case, it is desirable that the shape structure is integrally formed with a thick flat plate so that the shape itself is attached to the outside of the rising portion and the back surface side of the shape structure is vertically erected. There is also a method of fixing the existing rising portion with an anchor bolt as follows. There is little or no effect on the wave characteristics.

  For the quay and breakwater, the above method can also be used by using the quick-consolidation ready-mixer. It is also possible to fix the concrete (pre) molded body to the existing surface with anchor bolts or the like. However, when attaching a shape structure to an existing vertical section, quay or breakwater, apply fine sand-containing raw cement or concrete adhesive to the entire surface to prevent air, seawater, water, etc. from entering the gap. is necessary. If necessary, it is desirable that the shape structure is reinforced with reinforcing bars or the like.

  As for the size of the mountain-shaped structure shown in FIG. 3, the top shape of FIG. 3 has a great effect of reducing the stress, and if the angle between the base and the oblique line is made larger, the stress is further increased. However, it is judged that it is somewhat difficult and labor-intensive to finish the soil in such a shape by hand digging. If mechanical, there is room for potential. In addition, the length of one side of the bottom of the mountain-shaped structure is generally 20-40 cm by hand digging, and about 30-50 cm is preferable for mechanical. In the concavo-convex structure, it may be more difficult than the former to accurately obtain R by hand digging. Mechanical type is desirable. However, it is preferable to cut the hard end pipe at a radial position in the length direction. In this case, if it is an architectural building, it is easy to push it horizontally into uncured discarded concrete.

  Another method is to use the pipe itself as it is. That is, it is a combined shape of a concave surface and a convex surface. In such a case, place the soil flat and place a small amount of raw discarded concrete to a height of about half the pipe diameter, and then put a hard PVC pipe on the entire surface in the length direction. Next, we will put raw concrete to the top of the pipe and wait for it to dry before hitting the foundation concrete. However, this rigid PVC pipe should be filled with steel bars and concrete in advance, or in this case it is heavy, so it is reasonable to use a crane. Or, insert a score line in the length direction of the hard end pipe, insert a reinforcing bar in advance, insert a wedge to widen the split line, place it on a flattened soil, and pour raw discarded concrete at the same time as the split position of the hard PVC pipe It is also possible to use a method of pouring out the wedge so that the secant line closes after pouring.

  When using a semi-circular pipe and facing a double set of a circular shape, and using a cylinder, the reduction rate of seismic stress is the same as 90%. It can be said that it is preferable. When using a cylindrical pipe made of PVC pipe, go one step further, use a double pipe, that is, in a form where a small diameter PVC pipe is inserted into a large diameter PVC pipe, so-called double pipe system, In the small pipe, reinforcing steel bars and uncured raw cement are put in advance, inserted into a large-diameter PVC pipe, and reinforcing steel bars and uncured raw cement are inserted into the gaps. In this case, if the cement is hardened and has a certain length, it can be moved and constructed and arranged in the length (depth) direction. Note that the use of reinforcing steel bars is not necessarily essential, and it may be determined from the necessity of strength.

Furthermore, the two-stage product has a further effect, 1 / π ⁴ , and a reduction rate of 99%. Further, instead of the PVC pipe, the concrete pipe tube or the inside may be made of concrete. Reinforcing bars are also as described above. In this case, two-stage stacking is easy. Moreover, a double pipe system is also possible. However, Snell's law is a law showing the relationship because the refractive index of the boundary interface is different, and therefore a substance having a refractive index exceeding 1.000 and up to 2.500 can be used.

  The refractive index of soil, concrete and hard PVC is around 1.5. The higher the refractive index, the more likely the total reflection of the refracted wave that goes out to the atmosphere occurs. As a countermeasure, it is necessary to install the shape structure described above in order to escape. Furthermore, it is desirable that these substances avoid oxidation, hydroxylation or carbonate-forming substances due to aging.

  Examples of such substances having a refractive index of around 1.5 are natural rubber, polypropylene, ethylene propylene rubber, urethane rubber, polymethyl methacrylate resin, butyl rubber, nitrile rubber, polyethylene, polypropylene, nylon, styrene butadiene. Examples include rubber, vinyl chloride, chloroprene rubber, polycarbonate resin, polystyrene resin, urethane resin, asphalt, polyester resin, and polyethylene terephthalate resin. Metal materials include iron (refractive index 2.36), zinc (refractive index 2.42), duralumin (refractive index 1.48), and aluminum (refractive index 1.48).

  Among these substances, rubbers have a function necessary for applying Snell's law, but as another function, they are integrated with the back surface of the shape structure and have a function of stress relaxation of seismic waves.

  It is essential to wrap these sheets or molded products around the outer surface of the concrete pipe. This is because if the concrete pipe and the concrete are in direct contact with each other, it will be in contact with the same quality concrete, and since the refractive index is the same, the interface referred to by Snell's law will not be established. By interposing substances having different refractive indexes, the interface is recognized as a different type of interface, and Snell's law is established at each interface.

  When using multiple shape structures that receive seismic stresses, considering separate and integrated, separate bodies require at least a stress backup on the tip side, but by integrating them Therefore, there is a merit that the backup of the structure can be used and there is no need for a new backup. The above PVC pipe plays its role. Hard PVC pipes and concrete are both approximately the same in refractive index, so there is almost no effect on the refraction angle of seismic waves. The pipe diameter in this case is preferably about 10 to 20 cm in diameter. The length of the side of the chevron, which is a typical shape of the description, and the diameter of the unevenness have no influence on both the dynamics and the wave. Therefore, there are no particular restrictions on dimensions. It is only limited in workability and cost.

  The present invention reduces the force per unit area of the seismic force received by the foundation of the building and its rise, and bends the input wave in different directions, or distributes it in various directions. It is a devised one.

  In the present invention, a structure having a simple shape, such as a mountain shape or an uneven shape, having a cross-sectional shape with respect to a stress input to the structure, is basically attached to the entire surface from 50% in multiple rows. Furthermore, if more peace of mind is expected, it is preferable to include a protrusion with a width of about 50 to 100 cm around the building or a width in accordance with a necessary manual when supporting a heavy object such as a bridge pier. In addition, for example, three-dimensional structures such as boring pins, including various cones and their complex shapes, are attached to the entire surface from 50% in multiple rows. In addition, if you want more peace of mind, the degree of effect varies in proportion to the installation area, and in areas where there was little damage in the past earthquakes, an installation rate of 50% may be sufficient, but more safety and damage In order to make it small, it is preferable to attach a shape that extends over the entire surface or protrudes. In addition, when the shape structure is attached in multiple stages, it is desirable to attach the entire surface because the effect can be obtained by power. In addition to rolling and vertical earthquakes, there is no change in the basic purpose of direct earthquakes. In addition, it is relatively easy to install a new construction for pitching earthquakes and direct earthquakes, but in order to apply to existing houses, it is necessary to add concrete to the soil or strengthen the rise of the foundation. If it is carried out at the same time as remodeling, it can be constructed relatively inexpensively. On the other hand, the present invention can be applied to roll earthquakes with relatively low cost.

  The target structure can be applied to a base of an object that is damaged by a seismic force on a building, a structure, various kinds of structures such as a dike, a quay, a road, a pier, a railroad track, and a tombstone. Furthermore, for existing buildings and structures, it is possible to take countermeasures against rolling earthquakes by surrounding the four sides.

  Furthermore, recently, a survey result that the degree of shaking and destruction of buildings differs depending on the quality of the soil on which the structure is built has been repainted. The energy of the wave is proportional to the square of the wavelength, but if the stress is reduced, a corresponding effect can be obtained and the present invention is effective.

  Recently, it has been clarified that there is a difference in the damage of earthquakes that the structure itself receives depending on the quality of the soil, and there are many damages that the structure itself sinks due to liquefaction phenomenon. It has already been described that the present invention is also effective for the liquefaction phenomenon. As a liquefaction prevention structure, as shown in FIG. 12, the structure is arranged so as to form a box-shaped body consisting of four wall surfaces and a bottom surface near the foundation (possibly discarded concrete) and the rising part on the outside. In the case of an uneven shape such as a triangular shape such as a triangle or a circular shape in which the cross-sectional shape can be divided into a vertical stress and a shear stress by attaching or installing a shape structure outside the box-like body, The basic matters are the same as those of the stress reduction structure in that the side, and further, the three-dimensional simple substance is attached or installed so as to have at least one surface. However, the difference is that the upper side of the box-shaped body is set higher by about 10 cm than GL, and the distance between the four wall surfaces of the box-shaped body and the rising part of the structure is preferably about 50 to 100 cm from the periphery of the structure. However, since it will be difficult to cross the site of the neighbor, it may be selected as appropriate. In addition, it is safe to determine the depth of the bottom based on the moisture content of the soil, the sand content, etc., while respecting the opinions of experts. The ratio of the shape structures on the four wall surfaces and the bottom surface is preferably provided on the entire surface for safety. However, it may be slightly different depending on the type of earthquake that will occur in the future. For example, if you select only areas where only liquefaction occurs, areas where structures need to be destroyed and liquefied, and liquefaction countermeasures are not necessary, but the areas where the ground is mainly destroyed are structures. Good. The point is that liquefaction is only about 300 gal, but in the case of a structure, there is a possibility of over 1000 gal. Therefore, the degree of backup should also be considered. Others are the same as in the present theory, that is, the logic described in the problems 1 to 5, and the reduction rate is the same.

Claims (14)

  50% or more of the entire lower surface of the lower structure of the structure that is a continuous uneven surface composed of surfaces that each face is inclined with respect to the horizontal plane, and extends along the horizontal plane of the structure of the building or structure. A structure to reduce the stress of earthquakes received by structures characterized by being provided in   The outer surface of the portion of the rising portion structure that extends along the vertical surface of the structure, and has a continuous uneven surface structure, each of which has a surface inclined with respect to the vertical surface. 2. The structure for reducing the stress of an earthquake received by the structure according to claim 1, wherein the structure is provided in an area of 50% or more of the entire surface.   A continuous uneven surface structure consisting of surfaces that are inclined with respect to the vertical surface is embedded in the ground of a rising structure that extends along the vertical surface of a building or structure of a structure. A structure to reduce the stress of earthquakes received by a structure characterized by being provided in an area of 50% or more of the entire outer surface of the part.   The structure according to claim 1 or 2, wherein the structure is a building, and the substructure is a foundation of the building.   The structure according to claim 2 or 3, wherein the structure is a building, and the rising portion structure is a rising portion of a foundation of the building.   The upper surface of the lower structure opposite to the lower surface on which the continuous uneven surface shape structure is provided, and the surface in contact with the atmosphere is also provided with the continuous uneven surface shape structure. Item 5. A structure for reducing earthquake stress received by the structure according to any one of items 1, 2 or 4.   The rising portion structure has an inner surface on the opposite side to the outer surface on which the continuous uneven surface shape structure is provided, and the continuous uneven surface shape structure is also provided on a surface in contact with the atmosphere. A structure for reducing stress of an earthquake received by the structure according to claim 2.   The structure of the continuous irregular surface shape is a mountain shape such as a triangular shape such as a triangle, a circle or an ellipse, a pyramid such as a pyramid or a cone, a polyhedron, a sphere, or a combination of these shapes, or an inverse shape thereof. The structure for reducing stress of an earthquake received by the structure according to any one of claims 1 to 7, characterized by comprising:   The earthquake according to any one of claims 1, 2, 4, and 6, wherein the structure having the continuous uneven surface shape is further provided under the continuous uneven surface shape structure. Stress reduction structure.   The earthquake stress received by the structure according to any one of claims 1 to 9, wherein a medium having a refractive index that is not equal to an adjacent interface is selected as the interface of the continuous uneven surface-shaped structure. Reduction structure.   The refractive index of the medium when the continuous uneven surface shape structure is concrete is a medium having a refractive index larger than 1.0 and smaller than 2.50 different from the refractive index of concrete. A structure for reducing the stress of earthquakes received by the structure according to 10.   The structure for reducing earthquake stress received by a structure according to claim 10 or 11, wherein a rubber medium having an earthquake stress relaxation function is used as the medium.   The structure for reducing an earthquake stress received by a structure according to any one of claims 1 to 12, wherein the continuous uneven surface shape structure is provided integrally with the structure.   The structure according to any one of claims 1 to 12, wherein the continuous uneven surface-shaped structure is created separately from the structure and integrated with the structure. Stress reduction structure for earthquakes.

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