Artificial ground structure

Abstract

To apply base isolation effect to the entire artificial ground.SOLUTION: An artificial ground structure 1 comprises an artificial ground 2 that is separated from natural ground and is rotatably installed, and a rotation mechanism that rotatably supports the artificial ground 2. The rotation mechanism is connected to the artificial ground 2, converts earthquake motion into energy for rotating the artificial ground 2, accumulates the energy, and converts the accumulated energy into rotational force to rotate the artificial ground 2. A waterway 6 is provided between the artificial ground 2 and the natural ground 4. A plurality of artificial grounds 2 are connected to each other.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an artificial ground structure having a seismic isolation function.

Background Art

[0002] As a seismic isolation structure adopted in buildings, isolators including laminated rubber, sliding bearings, and rolling bearings that support the buildings are adopted (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, disasters caused by earthquakes include secondary disasters such as fires and lifeline interruptions in addition to primary disasters such as building collapses. Since the seismic isolation effect is applied only to buildings equipped with a seismic isolation structure, it is not possible to prevent secondary disasters occurring in the entire area. If the seismic isolation effect can be applied to the entire area, the disaster prevention performance of the entire area can be improved.

Means for Solving the Problems

[0005] The artificial ground structure for solving the above problems includes an artificial ground separated from the natural ground and provided rotatably, and a rotation mechanism that rotatably supports the artificial ground. The rotation mechanism is connected to the artificial ground, converts seismic motion into energy for rotating the artificial ground, accumulates the energy, and uses the accumulated energy to rotate the artificial ground.

Effects of the Invention

[0006] According to the present invention, the seismic isolation effect can be applied to the entire artificial ground.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0008] <Summary> The artificial ground structure includes an artificial ground that is separated from the natural ground and rotatable independently of the natural ground, and a rotation mechanism that rotatably supports the artificial ground. The artificial ground constitutes part of the city together with the natural ground. The rotation mechanism accumulates seismic energy as mechanical energy. The rotation mechanism uses the accumulated energy to slowly rotate the artificial ground itself. By converting seismic energy into mechanical energy and rotating the artificial ground at a low speed, the inertial force generated in the buildings on the artificial ground is reduced. In addition, a seismic isolation effect is also applied to the entire artificial ground. As a result, primary disasters and secondary disasters caused by earthquakes can be suppressed throughout the entire artificial ground.

[0009] <Specific Configuration of this Embodiment> (Artificial Ground) An embodiment of the artificial ground structure will be described with reference to FIGS. 1 to 3.

[0010] As shown in FIG. 1, the artificial ground structure 1 has an artificial ground 2. The artificial ground 2 is located in a depression 5 artificially formed in the natural ground 4. In the example of FIG. 1, a plurality of depressions 5 having a circular shape when viewed from the plane are connected at one or more locations. The artificial ground 2 is smaller than the diameter of one depression 5. A water channel 6 is provided between the depression 5 and the artificial ground 2.

[0011] The artificial ground 2 has a disc-shaped or columnar shape. A building 10 may be arranged on the plane 9 of the artificial ground 2. The building 10 is fixed to the artificial ground 2. In the central part 11 of the artificial ground 2, it is preferable to arrange a building 10 with high public nature such as a school, a hospital, a park, etc., or a high usage frequency by users including residents. In the outer peripheral part 12 surrounding the central part 11, it is preferable to arrange a building 10 with low public nature such as a house or a commercial facility. Thereby, the movement of people from the outer peripheral part 12 to the central part 11 is generated.

[0012] Further, the artificial ground 2 functions as a gear by providing a plurality of teeth 8 on the side surface. The teeth 8 are formed at equal intervals on the entire side surface 7. The teeth 8 may be provided on a frame or the like constituting the artificial ground 2. The artificial ground 2 is provided rotatably while being supported by a rotation mechanism described later.

[0013] In the example of FIG. 1, a plurality of artificial grounds 2 are provided on the natural ground 4. Each of the artificial grounds 2 may have the same size or different sizes. Each of the artificial grounds 2 is connected to each other by the meshing of the teeth 8 provided on its side surface. When one artificial ground 2 rotates, the rotational force is transmitted to the other connected artificial grounds 2, causing the other artificial grounds 2 to rotate. In the present embodiment, the artificial ground 2 rotates in one direction.

[0014] Users including residents of the artificial ground 2 can move between a plurality of artificial grounds 2 using the connecting part of the teeth 8 as a path. Also, it may be possible to move between the artificial ground 2 and the natural ground 4 by a bridge or the like (not shown).

[0015] (Rotation mechanism) Referring to FIG. 2, an example of the rotation mechanism 3 will be described. The rotation mechanism 3 is located inside the depression 5 and supports the artificial ground 2 from below.

[0016] The rotating mechanism 3 includes a rotary bearing 20 that supports the artificial ground 2, a conversion and accumulation mechanism 21, and a period adjustment mechanism 22. The conversion and accumulation mechanism 21 converts seismic motion into mechanical energy (kinetic energy) and accumulates the mechanical energy. The period adjustment mechanism 22 adjusts the rotation period of the artificial ground 2. In the present embodiment, as the mechanical energy, elastic energy generated by winding a torsion spring (a hairspring) described later is accumulated.

[0017] The conversion and accumulation mechanism 21 and the period adjustment mechanism 22 will be described. However, the conversion and accumulation mechanism 21 and the period adjustment mechanism 22 are not limited to the following examples. The rotary bearing 20 is fixed to the depression 5 of the natural ground 4. The rotary bearing 20 has a receiving member 23 and a plurality of balls 24. The receiving member 23 has a disk-like shape. Further, the receiving member 23 has an annular groove 25 in its plane. The annular groove 25 is provided along the edge of the receiving member 23 in the plane of the receiving member 23. A plurality of balls 24 are accommodated in the annular groove 25. The balls 24 support the artificial ground 2 from its bottom surface. While supporting the artificial ground 2, the balls 24 roll and move in the annular groove 25 to smoothly rotate the artificial ground 2.

[0018] The conversion and accumulation mechanism 21 has a pendulum 26, an accumulation unit 27, and a gear 28. The pendulum 26 makes a reciprocating motion when an external force including a horizontal component is applied. Due to the reciprocating motion of the pendulum 26, the torsion spring 36 accommodated in the accumulation unit 27 is wound up. The winding up of the torsion spring 36 may be either one-way winding when the pendulum 26 swings in one direction or two-way winding when the pendulum 26 swings in both directions.

[0019] The pendulum 26 has a rotating shaft portion 29, a rotating portion 30, and a power transmission member 31. The rotating shaft portion 29 is rotatably fixed to a receiving member 23 or the like. The rotating portion 30 has a pulley 32 (or a sprocket) and a weight 33. The pulley 32 and the weight 33 are rotatably supported directly or indirectly by the receiving member 23. The weight 33 is formed in a semicircular shape when viewed from a plane. The power transmission member 31 is a member that transmits a rotational force, such as a belt, a rope, or a chain. The power transmission member 31 is stretched between the rotating shaft portion 29 and the shaft portion of the pulley 32. The weight 33 transmits power to the rotating shaft portion 29 via the power transmission member 31 by reciprocating horizontally about the shaft portion of the pulley 32.

[0020] The length of the power transmission member 31 of the pendulum 26 and the weight of the weight 33 are adjusted according to the size of the artificial ground 2. That is, the power transmission member 31 of the pendulum 26 provided in the rotating mechanism 3 of the large artificial ground 2 is longer than the power transmission member 31 of the pendulum 26 provided in the rotating mechanism 3 of the small artificial ground 2. Note that even for artificial grounds 2 of the same size, the length of the power transmission member 31 and the weight of the weight 33 may be made different.

[0021] The rotating shaft portion 29 is connected to the storage portion 27 via a shaft portion 35 or the like. A torsion spring 36 is housed in the storage portion 27. When the shaft portion 35 rotates, the torsion spring 36 is wound. Thereby, the seismic motion input to the rotating mechanism 3 is stored in the torsion spring 36 as mechanical energy.

[0022] The shaft portion 35 of the storage portion 27 transmits a rotational force to the gear 28. A gang gear 38 of the period adjustment mechanism 22 meshes with the gear 28. The period adjustment mechanism 22 includes, in addition to the gang gear 38, an arm 39, a cam 40, and a hairspring 41. The gang gear 38 suppresses the torsion spring 36 from unwinding all at once. The arm 39 is provided so as to be swingable by the rotational force of the gang gear 38. The swing of the arm 39 is transmitted to the cam 40. The cam 40 reciprocates at regular time intervals due to the expansion and contraction of the hairspring 41. Thereby, since the rotation period of the gear 28 is adjusted, the artificial ground 2 rotates in one direction and at a constant speed.

[0023] <Operation of this Embodiment> Referring to FIG. 3, the operation of the artificial ground structure 1 will be described. When the torsion spring 36 of the storage part 27 is not wound, the artificial ground 2 maintains a stationary state. When an earthquake occurs, if the dominant period of the seismic motion matches the natural frequency of the pendulum 26 of any one of the artificial ground structures 1, the pendulum 26 resonates and swings greatly. Since the natural frequency of the pendulum 26 changes according to the length of the power transmission member 31 and the weight of the weight 33, when the natural frequency of any one of the pendulums 26 of the plurality of artificial grounds 2 matches the dominant period of the seismic motion, that artificial ground 2 rotates in the rotation direction D1. Along with this, the other artificial grounds 2 connected to the artificial ground 2 that has started to rotate also start to rotate.

[0024] The rotation mechanism 3 rotates the artificial ground 2 at a speed that reduces the inertial force generated in the building 10 to such an extent that damage to the building 10 can be suppressed. The rotation of the artificial ground 2 is attenuated by contact with the water in the water channel 6 and the frictional force between the rotary bearing 20 and the artificial ground 2, etc., and then stops. The building 10 located on the artificial ground 2 moves, for example, from the position indicated by the dashed line in FIG. 3 to the position indicated by the solid line. That is, since the rotational movement of the artificial ground 2 is not forcibly stopped, in many cases, the relative position with respect to the natural ground 4 when rotation starts is different from the relative position with respect to the natural ground 4 when rotation stops. As a result, before and after the rotation of the artificial ground 2, a north-facing house may change to a south-facing house, or vice versa. Also, the distance between a predetermined position of the artificial ground 2 and a building 13 such as a commercial facility or a station on the natural ground 4 may become shorter or vice versa.

[0025] By rotating the artificial ground 2 in this way, various changes and new vitality can occur in the city. As described above, according to the first embodiment, the following effects can be obtained.

[0026] <Effects of this Embodiment> (1) According to the above embodiment, the artificial ground 2 is separated from the natural ground 4 and supported by the rotation mechanism 3 so as to be rotatable. The rotation mechanism 3 accumulates the energy of an earthquake as mechanical energy for rotating the artificial ground 2, and rotates the artificial ground 2 itself by converting the accumulated mechanical energy into a rotational force. In this way, seismic motion is not directly transmitted from the natural ground 4 to the artificial ground 2, and part of the seismic energy is converted into the rotational energy of the artificial ground 2. Therefore, not only can damage to the building 10 on the artificial ground 2 caused by an earthquake be suppressed, but also a seismic isolation effect can be applied to the entire artificial ground 2.

[0027] (2) According to the above embodiment, a water channel 6 is provided between the artificial ground 2 and the natural ground 4. Therefore, the rotation of the artificial ground 2 can be attenuated by the resistance of the water in the water channel 6. (3) According to the above embodiment, the plurality of artificial grounds 2 are connected to each other so as to be able to transmit a rotational force. According to this, since the energy for rotating the artificial ground 2 is transmitted from one artificial ground 2 to the other artificial ground 2, the rotational motion of the artificial ground 2 can be attenuated in a short period.

[0028] (4) According to the above embodiment, the pendulums 26 provided in the rotation mechanism 3 that supports the plurality of artificial grounds 2 have different natural frequencies. Therefore, it becomes possible for any one of the pendulums 26 to correspond to the dominant period of the seismic motion that changes from time to time. Thus, the accuracy of rotation of any one of the plurality of artificial grounds 2 can be increased.

[0029] (5) According to the above embodiment, the period adjustment mechanism 22 adjusts the rotation period of the artificial ground 2. Therefore, the artificial ground 2 can be rotated in a fixed direction and at a fixed speed. (6) Even if the artificial ground 2 rotates, the central portion 11 of the artificial ground 2 has a small change in the relative positional relationship with respect to the natural ground 4. According to the above embodiment, a building 10 with high publicness or high user utilization frequency is arranged at the central portion 11 of the artificial ground 2, and a building 10 with relatively low publicness such as a house is arranged at the outer peripheral portion 12. According to this, after the artificial ground 2 rotates, the building 10 with high publicness or high user utilization frequency has a small change in the relative position with respect to the natural ground 4. Therefore, the users of the building 10 can easily grasp its position even after the artificial ground 2 rotates.

[0030] <Modification Example> The above embodiment can be implemented with the following modifications. Each embodiment and the following modification examples can be implemented in combination with each other within a technically non - conflicting range.

[0031] · In the above embodiment, the energy accumulated in the accumulation part 27 is used only for the rotational movement of the artificial ground 2. In addition to this, at least a part of the energy accumulated in the accumulation part 27 may be converted into electric energy, thermal energy, etc. For example, the electric energy may be used for the infrastructure of the artificial ground 2. Also, the electric energy may be used for a power source such as a motor that supplementarily applies a rotational force at the initial stage of rotation of the artificial ground 2.

[0032] · In the above embodiment, a plurality of artificial grounds 2 are connected. Instead of this, one artificial ground 2 may be provided on the natural ground 4 in a predetermined area. In this case, the teeth 8 provided on the side surface of the artificial ground 2 can be omitted.

[0033] · In the above embodiment, the water channel 6 is provided between the depression 5 and the artificial ground 2, but the water channel 6 may be omitted. · In the above embodiment, a building 10 with high publicness or high utilization frequency is provided at the central portion 11 of the artificial ground 2. The arrangement of the building 10 can be appropriately changed according to the size of the artificial ground 2, population density, etc. Also, there may be no building 10 on the artificial ground 2.

[0034] · In the above-described embodiment, one pendulum 26 was arranged for one artificial ground 2. Instead of this, a plurality of pendulums 26 having different natural frequencies may be arranged for one artificial ground 2. According to this, the probability that the natural frequency of any one of the pendulums 26 matches the dominant period of the earthquake can be increased. And the chance that the artificial ground 2 rotates when an earthquake occurs can be increased.

[0035] · At least a part of the rotation mechanism 3 can be changed to other known members. For example, a mechanism that converts the swinging of the pendulum 26 into electrical energy using a motor or the like may be used. <Supplementary Note> Next, the technical ideas that can be grasped from the above-described embodiment and alternative examples are appended below.

[0036] [A] The artificial ground structure according to claim 1, wherein a building with a high degree of publicness is arranged in the central part, and houses are arranged in the outer peripheral part. [B] An artificial ground separated from the natural ground and provided so as to be rotatable, and a rotation mechanism for rotatably supporting the artificial ground, wherein the rotation mechanism is connected to the artificial ground and converts and accumulates seismic motion into energy, an artificial ground structure.

Explanation of Reference Numerals

[0037] 1... artificial ground structure, 2... artificial ground, 3... rotation mechanism, 4... natural ground, 5... depression, 6... water channel, 8... tooth, 10... building, 20... rotation support, 21... conversion and accumulation mechanism, 22... period adjustment mechanism, 23... receiving member, 24... ball, 25... annular groove, 26... pendulum, 27... accumulation part, 28... gear, 29... rotating shaft part, 30... rotating part, 31... power transmission member, 32... pulley, 33... weight, 35... shaft part, 36... spiral spring, 38... gang wheel, 39... ankle, 40... template, 41... hairspring.

Claims

1. An artificial ground that is separated from the natural ground and is rotatably provided, and a rotation mechanism that rotatably supports the artificial ground, comprising the rotation mechanism being an artificial ground structure that is connected to the artificial ground, converts seismic motion into energy for rotating the artificial ground, accumulates the converted energy, and uses the accumulated energy to rotate the artificial ground.

2. The artificial ground structure according to claim 1, wherein a water channel is provided between the artificial ground and the natural ground.

3. Comprising a plurality of the artificial grounds, the artificial ground structure according to claim 1, wherein each of the artificial grounds is connected to be capable of transmitting a rotational force to each other.

4. the rotation mechanism has a pendulum that reciprocates in response to the seismic motion, the artificial ground structure according to claim 3, wherein the pendulums of the rotation mechanisms connected to the plurality of artificial grounds have different natural frequencies.

5. The artificial ground structure according to claim 1, wherein the rotation mechanism has a period adjustment mechanism for adjusting the rotation period of the artificial ground.

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