JPH06160249A - Performance determining method for earthquake isolating floor system and horizontal shaking test equipment therefor - Google Patents

Abstract

PURPOSE:To allow redetermination of the performance of an earthquake isolating floor system assembled at site. CONSTITUTION:An earthquake isolating floor assembled at site is moved horizontally by means of a plurality of hydraulic jacks 31, horizontal shaking force and moving amount are detected by means of a load gauge 32 and a displacement gauge 33, respectively, and measured in real time by means by a digital dynamic distortion gauge 34 and the measurement data is processed by means of a computer 35. Relationship between horizontal shaking force P(ton) and moving amount delta(cm) is displayed graphically on a monitor screen and overall frictional coefficient mu and spring constant SIGMAk are determined from the graph thus evaluating the performance of earthquake isolating floor system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for confirming the performance of a seismic isolated floor system which has been assembled on site, and a seismic isolated floor horizontal load test device for the method.

[0002]

2. Description of the Related Art In general, a seismic isolation floor system (Dynamic Floor System; DFS) floats the entire floor assembly from the building frame and supports it with seismic isolation devices. It has a structure that reduces to.

FIG. 8 to FIG. 11 show an example thereof, which has a double floor structure in which an upper floor 2 is constructed above a floor surface 1 of the building itself, and a plurality of seismic isolation devices 10 are arranged on the floor surface 1 at predetermined intervals. Are arranged to support the upper floor, and the seismic isolation device 10 serves as a seismic isolation floor 3 that absorbs vibrations such as an earthquake.

The seismic isolation device 10 is similar to that disclosed in Japanese Utility Model Publication No. 57-25942, and takes into consideration the property that the response of a structural floor to an earthquake is usually amplified by several times the input seismic wave. It has been configured. That is, in consideration of the property of the floor response, the vertical spring 11 and the horizontal spring 12 which are soft in the vertical and horizontal directions are provided to create a vibration system having a longer cycle than that of the structure. The damper 13 absorbs the vibration energy in the vertical direction and reduces the transmission to the double floor. This seismic isolation device 10
Slips in the horizontal direction when a seismic force (acceleration) of a set value or more is applied. In this horizontal direction, there is a gap between the base 14 of the seismic isolation device 10 and the sliding plate 15 on the floor 1. Sliding friction by the mounted friction material 22 exerts a damper action.

On the other hand, when the seismic isolation floor is elastically supported as described above, frictional force acts in the horizontal direction, so that the seismic isolation floor does not slide normally, but the floor vibrates in the vertical direction due to traveling of a carrier, etc. Environmental vibration as a problem. For this reason, in order to maintain the living environment in normal times, a fixing mechanism is provided in the vertical direction so that the seismic isolation device does not function in normal times. That is, the seismic isolation device 10 receives the loading load of the upper floor 2 by its main body 16, and 90% of the load supported by the main body 16 is placed on the vertical spring 11, and the remaining 10% is placed in the center of the main body 16 of the shaft 17. The stopper 18 and the stopper 18, and the stopper 18 is inserted in a state of being pulled by the extraction spring 19. When an up-and-down motion occurs due to an earthquake or the like, the stopper 18 is disengaged by the pulling force of the extraction spring 19 to release the normal fixing mechanism, and the support of the main body 16 is transferred to the elastic suspension by the vertical spring 11. , The seismic isolation effect is being demonstrated. 20
Is a set bolt screwed from the top plate 16a of the main body 16 to adjust the load sharing ratio between the vertical spring 11 and the shaft 17, 21 is a holding plate of the vertical spring 11, and 4 is a hydraulic cylinder used for adjusting the load sharing ratio. Is.

[0006]

By the way, the seismic isolation device of the seismic isolation floor system described above is used in a factory for a spring constant test of a single device, and a sliding friction between a friction material and a sliding plate which constitutes a sliding bearing of the seismic isolation device. Tested and shipped.

However, when a seismic isolation floor system is actually constructed, since a plurality of seismic isolation devices are attached, the performance may change slightly depending on the installation accuracy on site. In actual seismic isolation floor systems, there are often cushioning parts around the seismic isolation floor, but the effect of friction is not taken into consideration during design. For example, as shown in FIG. 12, a filling material 23 such as rubber, whose lower portion is easier to compress than the upper portion, is inserted into a gap between the upper floor 2 and the pillars 24 to form a filling floor,
When an earthquake occurs, the filling material 23 becomes
The structure which does not transmit the horizontal motion of the column or the like to the seismic isolated floor by going up from the joint portion 26 with 2 (Japanese Patent Publication No. 57-23061) may be designed by the influence of such a buffer portion. Sometimes not considered.

Therefore, when the seismic isolation floor is assembled on site,
It is extremely important to reconfirm the performance of the seismic isolation floor system, but conventionally, there was no means to reconfirm such seismic isolation performance.

The present invention has been made in view of the above problems, and takes into consideration the situation of the base-isolated floor assembly site (installation accuracy, engagement with the surroundings, etc.), the performance of the base-isolated floor system completed on-site assembly. It is to provide a method for confirming and a seismic isolation floor horizontal loading test device.

[0010]

In order to achieve the above object, a method for confirming the performance of a seismic isolation floor system according to the present invention is such that a seismic isolation floor that has been assembled on site is moved horizontally by a force applying means and the The force and the amount of movement in the horizontal direction are measured by sensors, and the measured data is arithmetically processed to graph the relationship between the horizontal force P (ton) and the amount of movement δ (cm).
The overall friction coefficient μ and spring constant Σk are determined from the graph (claim 1).

Further, the seismic isolation floor horizontal loading test apparatus of the present invention is
A plurality of hydraulic jacks that apply horizontal force to the seismic isolated floor that has completed on-site assembly, and a pump unit that moves the seismic isolated floor horizontally by operating these hydraulic jacks in synchronization.
A load meter that measures horizontal force and a displacement meter that measures the amount of movement in the horizontal direction, and the relationship between the horizontal force P (ton) and the amount of movement δ (cm) by collecting and processing these measurement data The calculation processing means for graphing is provided (Claim 2).

In the seismic isolated floor horizontal load test apparatus, a hydraulic jack for restoration and a pump unit thereof may be provided in addition to the hydraulic jack (claim 3), and the hydraulic jack is a separate type. Using a double-acting hydraulic jack,
It can also be used as a hydraulic jack for horizontal force application and restoration (claim 4).

[0013]

[Function] The first performance of the seismic isolation floor system is how much force the seismic isolation device starts to move during an earthquake, that is, when the seismic isolation effect is obtained, and the second is how much the vibration can be damped. It depends on (1) the magnitude of the friction coefficient μ between the seismic isolation device and the sliding plate, and (2) the magnitude of the horizontal spring strength (spring constant k). Therefore, by statically laterally moving the entire seismic isolation floor, grasping the relationship between the horizontal force P (ton) and the movement amount δ (ton), and obtaining the overall friction coefficient and spring constant, The performance can be confirmed (Claim 1).

[0014] MenShinyuka completing the field assembly is intended greater is the floor area of 1000m ² ~2000m ^2, give a horizontal pressure force MenShinyuka completing the field assembly of a plurality of hydraulic jacks, these When the hydraulic jacks are operated in synchronism with each other, the seismic isolation floor is moved horizontally to obtain a desired horizontal force P (ton) and a movement amount δ (cm) (claim 2).

In the seismic isolated floor horizontal load test device, a restoring hydraulic jack is provided in addition to the hydraulic jack for applying force to restore the original state (Claim 3). When used, it can be used for both horizontal application and restoration, which is advantageous in installation (claim 4).

[0016]

The present invention will be described below with reference to the illustrated embodiments. The seismic isolation device constructing the seismic isolation floor system in the present embodiment is the same as that described with reference to FIGS. 8 to 11.

The first performance of the seismic isolation floor system is how much force the seismic isolation device 10 starts to move during an earthquake, that is, when the seismic isolation effect is obtained. The second is how much vibration can be damped. These are (1) the magnitude of the friction coefficient μ between the seismic isolation device 10 and the sliding plate 15,
(2) It depends on the strength of the horizontal spring 12 (spring constant k). Therefore, the entire seismic isolation floor is statically moved laterally, the load (ton) as the horizontal force P and the displacement (cm) as the movement amount δ are measured, and the overall friction coefficient μ and spring constant are measured. Confirm the seismic isolation performance of the system by obtaining Σk.

At the actual site, the largest one is 1000
There are floor area m ² ~2000m ^2, which in testing as integral, it is necessary to devise to move the MenShinyuka horizontally. Therefore, as shown in FIG. 1, a plurality of hydraulic jacks 31 are used as the force applying means for moving horizontally, and these horizontal force applying hydraulic jacks 31 are operated by the pump unit 30 while synchronizing with each other, so that the seismic isolated floor is made horizontal. To move.
At the same time, the load applied by the hydraulic jack 31 is detected by the load meter 32, the horizontal movement amount of the seismic isolation floor is detected by the displacement meter 33, and the digital dynamic strain measuring instrument 34 measures in real time. The measurement data is collected and processed by the personal computer 35, and the relationship between the horizontal force P (ton) and the movement amount δ (cm) is graphed on the monitor screen, and the overall spring constant Σk and friction coefficient μ are plotted from the graph. Ask. In addition, the hydraulic jack 36 for restoration
And its pump unit 30 are also provided.

FIG. 2 and FIG. 3 show a seismic isolated floor horizontal loading test device specifically applied to a computer room seismic isolated floor. The outline of the seismic isolation floor targeted here is as follows.

Seismic isolation floor area: 665 m ² Number of devices: 32 full units, 16 half units Fixed load (steel frame weight, device weight, panel weight, stand weight, etc.): 58.74 t Loading load: 0.60 t Total load: 59.34 t Design horizontal spring constant (for 4): Σk = 0.60 t Design friction coefficient: μ = 0.06 (At design load, load = 150
Kg / cm ² ) In the figure, A1 to A4 indicate the locations of the hydraulic jacks 31 for horizontal force application. Regarding the force application method, considering that the force is applied at a position inside the seismic isolation floor and that the existing structure is used, the installation location of the hydraulic jack 31 is four points at approximately the center of the seismic isolation floor. The force was applied, and the reaction force was applied to the steel frame bracket 37 fixed to the slab by the hole-in anchor. Further, the bracket 37 is used for these A1 to A4 parts, and the hydraulic jack 31 for force is diverted into a hydraulic jack 36 for restoration, which is used when the seismic isolated floor is restored. That is, as the force applying hydraulic jack 31, a separation type double-acting type hydraulic jack in which the raising and lowering of the ram can be operated by switching the hydraulic pump is used and is used for force applying and restoring.
An electric hydraulic pump unit was used as the pump unit 30. Reference numeral 38 is a control switch of the pump unit 30 which operates the hydraulic jacks 31 while synchronizing them.

The maximum amount of deformation δmax due to the horizontal force mentioned above.
Was set to 15 cm in consideration of the use and installation of the hydraulic jack 31 and the performance of the displacement gauge. ΣPma with δmax = 15 cm
x = 12.4t, so the reaction force per location is calculated to be 3.1t at maximum.

Next, regarding the measuring method, a load meter (load cell) 32 is provided as L1 to L4 at the above A1 to A4 portions, and displacement gauges 33 are provided at two locations at the above A1 to A4 portion and the seismic isolation floor end portion. It was provided as D1 to D6. Then, the load P (ton) of horizontal force is given by the load cells L1 to L4.
The amount of deformation movement δ (cm) is simultaneously measured by the displacement gauges D1 to D6 via the dynamic strain measuring device 34, data processing is performed by the personal computer 35, and the load-displacement (P-
δ) The characteristics were obtained.

FIG. 4 and FIG. 5 show a part of the obtained “load-displacement” graphs, and FIG. 6 shows the results of the friction coefficient μ and the spring constant Σk obtained from such “load-displacement” graphs. .
In FIG. 6, tests No1 to No3 show the case where the buffer section described in FIG. 12 is provided.

FIG. 7 shows the load-displacement (P-δ) predicted from the design horizontal spring constant Σk = 0.60t and the design friction coefficient μ = 0.06 (shipping load = 150Kg / cm ² at design load) at the time of shipment. ) Shows characteristics. From the comparison between this predicted load-displacement characteristic and the measured load-displacement characteristic, the following can be said as the result of this test.

(1) The apparent friction coefficient is μ = 0.07 to 0.07
It is about 5, which is slightly larger than the design value under design load. The reason is that (a) the static friction coefficient is larger than the dynamic friction coefficient, so this effect is included in the apparent friction coefficient. b) The friction coefficient depends on the surface pressure, and it is considered that the friction coefficient is larger than that under the design load because there is almost no loading load in this test. Therefore, the result is generally satisfactory. It can be called a value.

(2) The apparent spring constant is a little smaller than the design value, but the smaller spring constant is because it acts to make the period of the seismic isolation floor longer. It can be considered that it has an advantageous effect on the performance of. Therefore,
As a result, it can be said that they are fully satisfied.

(3) In the comparison of the presence / absence of the cushioning portion (for example, FIGS. 4 and 5), the influence of the presence of the cushioning portion can be seen at the initial stage of deformation, but the influence as the load is at most 1 to 2 t,
It can be said that the extraction of the buffer portion is generally good.

(4) Among the measured load-displacement characteristics, the reason why the gradient becomes smaller when the load is close to zero in the process of restoring from the maximum deformation is considered to be due to the influence of the inertial force due to the restoring force of the spring. .

(5) From the above (1) to (4), it can be judged that the test was sufficiently satisfactory due to the smooth application of force, and it was confirmed that the performance of the seismic isolation floor was sufficient. It can be said that it was done.

In this way, it is possible to confirm the performance of the seismically isolated floor system that has actually been assembled, and it is possible to perform a simulation without actually inputting the seismic force. In addition, the experiment can be performed even after the computer or the like is loaded.

[0031]

As described above, according to the method or apparatus of the present invention, the following excellent effects can be obtained.

(1) Statically laterally move the whole seismic isolation floor to grasp the relationship between the horizontal force P (ton) and the movement amount δ (cm), and obtain the overall friction coefficient and spring constant. This makes it possible to confirm the performance of the seismically isolated floor system that has actually been assembled (claims 1 and 2). Therefore, the simulation can be performed without actually inputting the seismic force. Further, the experiment can be performed even after the computer is loaded.

(2) In particular, in the seismic isolated floor horizontal loading test apparatus of claim 3, a horizontal loading is applied to the seismic isolated floor which has been assembled on site by a plurality of hydraulic jacks, and these hydraulic jacks are synchronized. However, since the seismic isolated floor having a large floor area is correctly moved horizontally, a desired horizontal force P (ton) and a movement amount δ (cm) can be obtained.

(3) According to the third or fourth aspect of the invention, the seismic isolation floor is brought into the original state by the hydraulic jack for restoration or the split type double-acting hydraulic jack which can be shared for horizontal force application and restoration. Can be restored.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of a performance confirmation method of a base-isolated floor system according to the present invention.

FIG. 2 is a diagram showing a positional relationship between a hydraulic jack and a displacement gauge of a seismic isolated floor horizontal load test apparatus according to an embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a seismic isolated floor horizontal loading test apparatus according to an embodiment of the present invention.

[Fig. 4] "Load-displacement" obtained from the measurement values of the test equipment
It is a figure which shows the example of a graph.

FIG. 5 is a diagram similarly showing an example of a “load-displacement” graph obtained from measured values.

FIG. 6 is a diagram showing a result of obtaining a friction coefficient μ and a spring constant Σk from a “load-displacement” graph.

FIG. 7 is a diagram showing load-displacement (P-δ) characteristics predicted at the time of shipping.

FIG. 8 is a diagram showing an outline of a conventional seismic isolation floor system.

9 is a diagram showing a seismic isolation device that constitutes the seismic isolation floor system of FIG. 8. FIG.

10 is a cross-sectional view showing the seismic isolation device of FIG.

FIG. 11 is a top view showing the seismic isolation device of FIG. 9.

FIG. 12 is a diagram illustrating a conventional cushioning portion around a base isolation floor.

[Explanation of symbols]

 10 Seismic Isolation Device 12 Horizontal Spring 15 Sliding Plate 22 Friction Material 30 Pump Unit 31 Hydraulic Jack for Applying 32 Load Meter 33 Displacement Meter 34 Digital Dynamic Strain Measuring Instrument 35 Personal Computer 36 Hydraulic Jack for Restoration 37 Steel Bracket 38 Control switch

Claims (4)

[Claims] 1. A seismic isolated floor, which has been assembled on site, is horizontally moved by a force applying means, and the horizontal force and the amount of movement in the horizontal direction are respectively measured by sensors, and the measured data is arithmetically processed to make it horizontal. A method of confirming the performance of a base-isolated floor system, characterized in that the relationship between the applied force and the amount of movement is graphed, and the overall friction coefficient and spring constant are obtained from the graph. 2. A plurality of hydraulic jacks that apply a horizontal force to the seismic isolation floor that has been assembled on site, a pump unit that moves the seismic isolation floor horizontally by operating these hydraulic jacks in synchronization, and a horizontal force And a displacement meter for measuring the amount of movement in the horizontal direction and an arithmetic processing means for collecting and processing the measurement data of these to graph the relationship between the horizontal force and the amount of movement. Seismic isolation floor horizontal loading test equipment. 3. The seismic isolated floor horizontal load test apparatus according to claim 2, further comprising a restoring hydraulic jack and a pump unit for the restoring, in addition to the hydraulic jack. 4. The seismic isolated floor horizontal force test according to claim 2, wherein a separate double-acting hydraulic jack is used as the hydraulic jack, and the hydraulic jack is also used as a horizontal force restoring and restoring hydraulic jack. apparatus.