JPH0742745B2 - Friction type seismic isolation device static friction edging device - Google Patents

Description

The present invention relates to a static friction edging device for a friction-type seismic isolation device.

<< Conventional Technology >> The development of seismic isolation devices has been revitalized in recent years, and recently friction-based seismic isolation devices are also being researched for practical use. This friction type seismic isolation device uses clone friction force,
When a large force that exceeds the maximum static frictional force acts on the building in the horizontal direction, the frictional force is cut off and the building slides out. The friction-type seismic isolation device is composed of a pair of upper and lower horizontal friction plates arranged between the lower part of the building and the foundation as one unit, and a low friction sliding member is interposed between these friction plates. Since the vertical thickness of the friction plate is only a few centimeters, there is an advantage that the space under the building can be significantly reduced as compared with the conventional seismic isolation device using laminated rubber.

<< Problems to be Solved by the Invention >> However, the conventional friction-type seismic isolation device has a problem that the maximum static friction force is very large because the weight of the building is large and the building does not start to slide unless a large earthquake occurs. Because of this,
In a small earthquake, the seismic isolation did not work, and it was difficult to apply the friction-type seismic isolation device especially to buildings containing computers and communication equipment.

The present invention has been devised to solve the above problems, and provides a static friction edging device for a friction-type seismic isolation device that allows the static friction to be quickly cut off and the building to start sliding even in medium and small earthquakes. The purpose is to do.

<< Means for Solving the Problem >> In order to achieve the above object, the static friction edging device of the friction-type seismic isolation device of the present invention has a magnetic force composed of a pair of elements that repel or attract by magnetic force between the building and the foundation. A unit is provided, and the direction of repulsion or attraction of the magnetic force unit is set to the direction of the inertial force of the building at the time of an earthquake, and instead of reducing the maximum static friction force, the force of repulsion or attraction of the magnetic force unit The sum of the inertial force of the building and the maximum static friction force is set so as to exceed the maximum static frictional force.

<Operation> In the static friction edging device of the friction-type seismic isolation device configured as described above, the inertial force of the building at the time of an earthquake is apparently increased by the repulsion or suction force of the magnetic force unit, and this apparent inertial force is generated by the friction plate. When the maximum static frictional force is exceeded, the frictional force is cut off and the building begins to slide. Therefore, it is possible to prevent the horizontal force of the earthquake from being transmitted to the building even in the middle and small earthquakes.

«Examples» Examples of the present invention will be described below with reference to the drawings. First
The figure schematically shows a side surface of a building 2 in which a friction-type seismic isolation device 1 is installed. This friction type seismic isolation device 1 is a friction plate
The maximum frictional force of 6 and 7 is left unchanged, and a horizontal force is applied to the building 2 to cause the building 2 to slide. First, the edging device shown in FIG. 1 is composed of a total of four sets of superconducting coils including a pair of superconducting coils 20 and 21 as one set, and the attraction force of the superconducting coils 20 and 21 is applied to the building 2. So that it works horizontally. Specifically, Fig. 1 shows a part of a plan view of the lower part of the building 2, in which superconducting coils are provided on the four surfaces of the short columns 22 projecting from the lower part of the building 2.
20 is attached, and another superconducting coil 21 is arranged facing the superconducting coil 20. The superconducting coil 21 is supported by a column 23 protruding from the upper surface of the foundation 3 so as to be movable in the arrow direction, and a stopper 24 is attached to the rear portion of the superconducting coil 21. The current control for the superconducting coils 20 and 21 is carried out by the control device 25, and the control device 25 is activated by a signal from the seismic sensor 26. The four sets of superconducting coils are arranged at right angles to each other in the XY directions, and the magnitude and direction of the horizontal force F on the building 2 can be freely controlled by the amount of current flowing through each superconducting coil. Specifically, the magnitude of the horizontal force F is such that the sum of the inertial force of the building 2 and the horizontal force at the time of an earthquake exceeds the maximum static force of the friction plates 6 and 7, and the direction of the horizontal force F is the inertial force. It is in the same direction as. Since the horizontal force F does not need to be very large, a normal temperature normal conducting coil may be used for the magnetic force unit.

The edging device shown in FIGS. 2 and 3 has a plurality of magnetic force units each including a superconducting coil 29 and a permanent magnet 30 (only two sets are shown in FIG. 3, but a plurality of sets are arranged vertically and horizontally). The repulsive force of the superconducting coil 29 and the permanent magnet 30 is applied to the building 2 in the horizontal direction. For details, in Figures 2 and 3, 31 is the pillar of the building 2, 32
Reference numerals 33 and 33 are lower beams, and the friction plates 6 and 7 are arranged below the columns 31, and the magnetic force units are arranged below the lower beams 32 and 33. That is, the permanent magnet 30 is attached to the lower surfaces of the lower beams 32 and 33, and the superconducting coil 29 is provided on the upper surface of the foundation 3. The permanent magnet 30 and the superconducting coil 29 may be replaced with each other. Further, the superconducting coil 29 and the permanent magnet 30 are arranged so as to be slightly offset in the horizontal direction so that the magnetic repulsive force is generated in the XY directions. The control device 34 takes charge of the current control of the superconducting coil 29, and the magnitude and direction of the horizontal force F on the building 2 can be freely controlled. The magnitude and direction of the horizontal force F are the same as those described with reference to FIG. The control device 34 is adapted to start operation in response to a signal from the seismic sensor 35.

The magnetic force unit used in this embodiment can be modified in various ways, such as a pair of superconducting coils, a superconducting diamagnetic material, a combination of a magnetic field generating superconducting coil applying the principle of an electromagnetic propulsion ship, and a conducting conductor.

In the edging device described above, the inertial force and the horizontal F generated by the magnetic force unit simultaneously act on the building 2 during an earthquake, and the resultant force exceeds the maximum static friction force of the friction plates 6 and 7,
It is possible to prevent the horizontal frictional force from being transmitted to the building 2 due to the static frictional force being cut off and the building 2 starting to slip even in a medium or small earthquake.

Furthermore, when performing edging of static friction with horizontal force F,
There is a great effect in terms of the magnitude of the applied force vs. the sliding effect, about 1 /
Since the effect of μ (μ: friction coefficient of friction plate) is multiplied, the magnetic unit can be small. Further, since the horizontal force F is applied, it can be easily arranged even under the lower beam, so that the application points of the horizontal force F can be dispersed over a wide range, and as a result, one magnetic unit can be downsized. In addition, the type in which the horizontal force F is applied requires less vertical space between the lower portion of the building 2 and the upper surface of the foundation 3, and the space advantage of the friction-type seismic isolation device can be utilized as it is.

As described above, since the device of the present invention requires a large amount of electric power, it is preferable to provide an electric power storage system using a toroidal superconducting coil in the basement of a building to store a permanent current and use it during an earthquake.

<Effect of the invention> The apparent inertial force of the building is increased by the magnetic force unit and the apparent frictional force of the friction plate is cut by this apparent inertial force, so that the building starts to slip even in a small or medium earthquake and the earthquake It is possible to prevent horizontal forces from acting on the building.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a plan view of an edge cutting device according to a preferred embodiment of the present invention, FIG. 2 is a side view of an edge cutting device according to another embodiment, and FIG. FIG. 3 is a sectional view taken along the line III-III in FIG. 2 …… Building 3 …… Basic 6,7 …… Friction plate 20,21,29 …… Superconducting coil 30 …… Permanent magnet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsutoshi Okuma 2-3 Kandaji-cho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo headquarters (72) Inventor Atsushi Takeuchi 2-3 Kandaji-cho, Chiyoda-ku, Tokyo Stock company Obayashi Tokyo head office (56) Reference JP-A-64-66335 (JP, A) JP-A-64-66337 (JP, A)

Claims (1)

[Claims] 1. A building and its foundation are made unbonded structure, and the weight of said building is supported by a pair of upper and lower friction plates disposed on the upper surface of said foundation, and a sliding member is interposed between said pair of friction plates. In the friction-type seismic isolation device configured as described above, a magnetic force unit composed of a pair of elements that repels or attracts by magnetic force is disposed between the building and the foundation, and the direction of the repulsive force or the attractive force of the magnetic force unit acts in an earthquake direction. In the direction of the inertial force of the building at the time, and the total of the repulsive or attractive force of the magnetic force unit and the inertial force of the building is set to exceed the maximum static frictional force of the friction-type seismic isolation device. Static friction edging device.