Method for confirming the rigidity of a structure, method for measuring the period of a structure, system for confirming the rigidity of a structure, and system for measuring the period of a structure

Abstract

To easily and accurately evaluate the rigidity and period of structures. [Solution] A method for confirming the rigidity of a structure having a restoring device installed between a substructure and a superstructure, comprising: a substructure-side base installed on the substructure side of the restoring device; a superstructure-side base installed on the superstructure side of the restoring device; and a tensile force applying device installed between the substructure-side base and the superstructure-side base, wherein the tensile force applying device is activated with one of the substructure-side base or the superstructure-side base as the reaction force point and the other of the substructure-side base or the superstructure-side base as the point of application of the tensile force, and the rigidity of the structure is confirmed by measuring the tensile force and the relative displacement between the substructure and the superstructure.

Description

Technical Field

[0001] The present invention relates to a method for confirming the rigidity of a structure, a method for measuring the period of a structure, a system for confirming the rigidity of a structure, and a system for measuring the period of a structure.

Background Art

[0002] In a seismic isolation structure, a seismic isolation device (an example of a restoring device) such as laminated rubber is interposed between the upper structure and the lower structure. When such a seismic isolation device deteriorates over time, for example, its rigidity increases and its period shortens, resulting in the inability to ensure seismic isolation performance. As methods for evaluating the performance of a seismic isolation device, the following two methods are known. One is a method of jacking up the structure, temporarily removing the seismic isolation device, and inspecting the horizontal rigidity in a test site. The other is a method of installing an accelerometer on an existing building (structure), applying a relative displacement between the upper structure and the lower structure using a tool such as a hydraulic jack, and then rapidly releasing the applied force to vibrate the existing building and measure its period. For example, in Patent Document 1, with a seismic isolation device installed between the lower structure (floor) and the upper structure (article), after forcibly displacing the upper structure, it is freely vibrated to test the performance of the seismic isolation device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The first method described above requires jacking up the building to temporarily remove the seismic isolation device. Considering the impact on the existing building and safety concerns, this would be a large-scale construction project requiring high costs. The second method involves rapidly releasing the hydraulic pressure from the hydraulic jacks to vibrate the superstructure. However, if the hydraulic pressure is not completely released while the superstructure is vibrating, it will affect the vibration, making it difficult to accurately measure the period.

[0005] This invention has been made in view of the above-mentioned problems, and its purpose is to perform the evaluation of structures (evaluation of horizontal stiffness and natural period) simply and accurately. [Means for solving the problem]

[0006] The main invention for achieving the above objective is a method for confirming the rigidity of a structure having a restoring device installed between a substructure and a superstructure, comprising: a substructure-side base installed on the substructure side of the restoring device; a superstructure-side base installed on the superstructure side of the restoring device; and a tensile force applying device installed between the substructure-side base and the superstructure-side base, wherein the tensile force applying device is activated with one of the substructure-side base or the superstructure-side base as the reaction force point and the other of the substructure-side base or the superstructure-side base as the point of application of the tensile force, and the rigidity of the structure is confirmed by measuring the tensile force and the relative displacement between the substructure and the superstructure.

[0007] Furthermore, a method for measuring the period of a structure having a restoring device installed between a substructure and an upper structure, comprising: a substructure-side base installed on the substructure side of the restoring device; an upper structure-side base installed on the upper structure side of the restoring device; and a tensile force applying device installed between the substructure-side base and the upper structure-side base, wherein the tensile force applying device is operated with one of the substructure-side base or the upper structure-side base as the reaction force point and the other of the substructure-side base or the upper structure-side base as the point of application of the tensile force, and when the relative displacement between the substructure and the upper structure reaches a predetermined displacement amount, the application of the tensile force by the tensile force applying device is released, and the period of the structure is measured.

[0008] Other features of the present invention will be revealed in the specification and drawings described below. [Effects of the Invention]

[0009] According to the present invention, structures can be evaluated easily and accurately. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view of the seismic isolation structure 1 equipped with the evaluation system 20 of this embodiment (a plan view of the lower part of the seismic isolation device 10). [Figure 2] This is a plan view of the seismic isolation structure 1 equipped with the evaluation system 20 of this embodiment (a plan view of the upper part of the seismic isolation device 10). [Figure 3] Figures 3A to 3C are explanatory diagrams of the configuration of the evaluation system 20. Figure 3A is a side view showing the seismic isolation layer of the seismic isolation building 1, Figure 3B is a cross-sectional view AA of Figure 3A (a cross-sectional view along the XZ plane), and Figure 3C is a cross-sectional view BB of Figure 3A (a cross-sectional view along the YZ plane). [Figure 4] This is a flowchart illustrating the period measurement method using the evaluation system 20 of this embodiment. [Figure 5] Figures 5A to 5C show the state in which tensile force is applied by the retractable jack 23. [Figure 6]Figures 6A to 6C show the state after the tensile force applied by the retraction jack 23 has been released. [Figure 7] This is a flowchart illustrating the method for verifying rigidity using the evaluation system 20 of this embodiment. [Figure 8] This is an explanatory diagram of the evaluation system 20A in a modified example. [Modes for carrying out the invention]

[0011] The following information will become clear from the description in the specification and drawings described later.

[0012] (Aspect 1) A method for confirming the rigidity of a structure having a restoring device installed between a substructure and a superstructure, comprising: a substructure-side base installed on the substructure side of the restoring device; a superstructure-side base installed on the superstructure side of the restoring device; and a tensile force applying device installed between the substructure-side base and the superstructure-side base, wherein the tensile force applying device is operated with one of the substructure-side base or the superstructure-side base as the reaction force point and the other of the substructure-side base or the superstructure-side base as the point of application of the tensile force, and the rigidity of the structure is confirmed by measuring the tensile force and the relative displacement between the substructure and the superstructure.

[0013] According to the method for confirming the rigidity of a structure in Embodiment 1, the rigidity (horizontal rigidity) of a structure can be confirmed simply and accurately. Therefore, the evaluation of the structure can be performed simply and accurately.

[0014] (Aspect 2) A method for measuring the period of a structure having a restoring device installed between a lower structure and an upper structure, comprising a lower structure side base installed on the lower structure side of the restoring device, an upper structure side base installed on the upper structure side of the restoring device, and a tensile force applying device installed between the lower structure side base and the upper structure side base. Using one of the lower structure side base or the upper structure side base as a reaction point and the other of the lower structure side base or the upper structure side base as an action point of the tensile force, the tensile force applying device is operated. When the relative displacement between the lower structure and the upper structure reaches a predetermined displacement amount, the application of the tensile force by the tensile force applying device is released, and the period of the structure is measured. This is a method for measuring the period of a structure.

[0015] According to the method for measuring the period of a structure of Mode 2, the period (natural period) of the structure can be measured simply and accurately. The evaluation of the structure can be performed simply and accurately.

[0016] (Mode 3) The method for measuring the period of a structure according to Mode 2, which preferably has a tensile force restraint device for restraining the tensile force of the tensile force applying device.

[0017] According to the method for measuring the period of a structure of Mode 3, the application of the tensile force by the tensile force applying device can be easily released.

[0018] (Mode 4) The method for measuring the period of a structure according to Mode 3, wherein the other of the lower structure side base or the upper structure side base has a tension member connected to the side of one of the lower structure side base or the upper structure side base, the tensile force restraint device has a gripping portion for gripping the tension member, and when the tensile force applying device pulls the tension member, the release of the restraint of the tensile force by the tensile force restraint device is preferably performed by releasing the tension member at the gripping portion.

[0019] According to the method for measuring the period of a structure of Mode 4, the restraint of the tensile force can be released without affecting the period of vibration. Therefore, the period can be measured more accurately.

[0020] (Aspect 5) A method for measuring the period of a structure as described in any of embodiments 2 to 4, wherein it is desirable to set the required number of tensile force applying devices according to the total required amount of tensile force.

[0021] According to the period measurement method for structures in embodiment 5, the tensile force necessary for the relative movement of the superstructure and substructure can be generated. Therefore, the relative displacement of the superstructure and substructure can be reliably achieved.

[0022] (Aspect 6) A method for measuring the period of a structure according to any one of claims 2 to 5, wherein the tensile force application device is arranged symmetrically with respect to the axis in the direction of application that passes through the rigid center of the structure.

[0023] According to the period measurement method for structures in embodiment 6, the superstructure can be vibrated by moving it parallel to the axis relative to the substructure (it can be vibrated in a direction along the axis). This makes it possible to determine the accurate period and horizontal stiffness.

[0024] (Aspect 7) A structural rigidity verification system having a restoring device installed between a substructure and a superstructure, comprising: a substructure-side base installed on the substructure side of the restoring device; a superstructure-side base installed on the superstructure side of the restoring device; and a tensile force application device installed between the substructure-side base and the superstructure-side base, wherein the tensile force application device applies a tensile force with one of the substructure-side base or the superstructure-side base as the reaction point and the other of the substructure-side base or the superstructure-side base as the point of application, and the rigidity of the structure is verified based on the tensile force and the relative displacement between the substructure and the superstructure.

[0025] According to the structural rigidity verification system of Embodiment 7, the rigidity (horizontal rigidity) of a structure can be easily and accurately verified. Therefore, the evaluation of the structure can be easily and accurately performed.

[0026] (Pattern 8) A period measurement system for a structure having a restoring device installed between a substructure and a superstructure, comprising: a substructure-side base installed on the substructure side of the restoring device; a superstructure-side base installed on the superstructure side of the restoring device; and a tensile force applying device installed between the substructure-side base and the superstructure-side base, wherein the tensile force applying device applies a tensile force with one of the substructure-side base or the superstructure-side base as the reaction force point and the other of the substructure-side base or the superstructure-side base as the point of application, and when the relative displacement between the substructure and the superstructure reaches a predetermined displacement amount due to the tensile force, the application of the tensile force by the tensile force applying device is released to measure the period of the structure.

[0027] According to the structural period measurement system of Embodiment 8, the period (natural period) of a structure can be measured easily and accurately. Therefore, the evaluation of the structure can be performed easily and accurately.

[0028] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. The same or equivalent components, members, etc. shown in each drawing are denoted by the same reference numerals, and redundant explanations will be omitted as appropriate.

[0029] ===Implementation Method=== <<Regarding the structure>> Figure 1 is a plan view of the seismic isolation structure 1 equipped with the evaluation system 20 of this embodiment (a plan view of the lower part of the seismic isolation device 10 (described later)). Figure 2 is a plan view of the seismic isolation structure 1 equipped with the evaluation system 20 of this embodiment (a plan view of the upper part of the seismic isolation device 10 (described later)). Figures 3A to 3C are explanatory diagrams of the configuration of the evaluation system 20. Figure 3A is a side view showing the seismic isolation layer portion of the seismic isolation building 1, Figure 3B is a cross-sectional view AA of Figure 3A (a cross-sectional view along the XZ plane), and Figure 3C is a cross-sectional view BB of Figure 3A (a cross-sectional view along the YZ plane). Figures 3A to 3C show a state in which there is no relative displacement between the superstructure 2 and the substructure 4.

[0030] In this embodiment, each direction is defined as shown in the figures. Specifically, one of the two orthogonal directions (two horizontal directions) in the horizontal plane (here, the direction along the arrow (tension direction) in Figures 1 and 2) is defined as the X direction, and the other as the Y direction. The direction perpendicular to the above horizontal plane (the direction perpendicular to the X and Y directions) is defined as the Z direction. The Z direction is the direction along the vertical direction, with the upper side of the vertical direction being defined as "up" and the lower side being defined as "down".

[0031] As shown in Figure 3A and other figures, the seismic isolation structure 1 of this embodiment is a seismic isolation structure in which a seismic isolation device 10 is interposed in the gap between the superstructure 2 and the substructure 4 (hereinafter also referred to as the seismic isolation layer). An evaluation system 20 is also located in the seismic isolation layer.

[0032] The superstructure 2 is, for example, a structure such as a building, floor, or large equipment.

[0033] The substructure 4 is a structure that supports the superstructure 2 and transmits the load to the ground, and is formed below the superstructure 2.

[0034] As shown in Figure 3A, the seismic isolation device 10 is installed between the superstructure 2 and the substructure 4. More specifically, the seismic isolation device 10 is installed between the seismic isolation upper foundation 2A, which is provided to protrude downward from the superstructure 2, and the seismic isolation lower foundation 4A, which is provided to protrude upward from the substructure 4.

[0035] Furthermore, as shown in Figures 1 and 2, multiple seismic isolation devices 10 are arranged in the seismic isolation layer of the seismic isolation structure 1 in the X-axis direction and the Y-axis direction, respectively (specifically, four in the X-axis direction and five in the Y-axis direction). Each seismic isolation device 10 shares and supports the weight of the superstructure 2 at its respective location.

[0036] As shown in Figure 3A, the seismic isolation device 10 of this embodiment is constructed by sandwiching a laminated rubber 12 (for example, a cylindrical elastic body made by alternately laminating thin circular steel plates and rubber layers vertically) between a pair of upper and lower flange plates (upper flange plate 11, lower flange plate 13). The lower flange plate 13 is fixed to the lower seismic isolation foundation 4A by bolts (not shown), and the upper flange plate 11 is fixed to the upper seismic isolation foundation 2A by bolts (not shown).

[0037] Furthermore, the seismic isolation device 10 supports the superstructure 2, and the laminated rubber 12 undergoes horizontal shear deformation in response to the horizontal force caused by the relative displacement between the superstructure 2 and the substructure 4, thereby lengthening the period of the horizontal vibration of the superstructure 2 (functioning as a seismic isolation bearing). The seismic isolation device 10 also has a restoring function that restores the relative displacement between the superstructure 2 and the substructure 4 to its original state (the state shown in Figure 3A). In other words, in this embodiment, the seismic isolation device 10 corresponds to a restoring device.

[0038] <Evaluation System 20> The seismic isolation device 10 (laminated rubber 12) deteriorates over time, reducing its seismic isolation performance. For example, deterioration causes the rubber to harden, increasing its rigidity. This shortens the vibration period. Therefore, the presence or absence of deterioration can be evaluated by measuring the rigidity or period. However, conventionally, it has been difficult to measure rigidity and period easily and accurately for the following reasons.

[0039] For example, one method involves jacking up the structure, temporarily removing the seismic isolation devices, and then testing the horizontal rigidity at a test site. However, in this case, jacking up the building is necessary to remove the seismic isolation devices, and considering the impact on the existing building and safety, this would be a large-scale construction project requiring high costs.

[0040] Another method involves installing accelerometers on an existing building (structure), applying relative displacement to the superstructure and substructure using tools such as hydraulic jacks, and then rapidly releasing the applied force to vibrate the existing building and measure its period. In this case, typically, for example, hydraulic jacks are installed on a retaining wall continuous with the substructure, and the retaining wall is used as a reaction point to push against the superstructure (building, etc.). Then, the superstructure is vibrated by rapidly releasing the hydraulic pressure. However, if the hydraulic pressure is not completely released when the superstructure vibrates, it will affect the vibration, making it difficult to accurately measure the period.

[0041] Therefore, in this embodiment, an evaluation system 20 is provided between the superstructure 2 and the substructure 4. As will be described later, the evaluation system 20 applies a tensile force between the superstructure 2 and the substructure 4 and releases the tensile force without affecting the vibration period. This allows for easy and accurate measurement of the stiffness and period of the seismic isolation structure 1. The evaluation system 20 functions as both a period measurement system and a stiffness verification system. In other words, the evaluation system 20 corresponds to both a period measurement system and a stiffness verification system.

[0042] As shown in Figures 1 and 2, multiple evaluation systems 20 are installed in the seismic isolation layer of the seismic isolation structure 1 (in this case, in three locations). Furthermore, the multiple evaluation systems 20 are installed symmetrically with respect to axis C. Here, axis C is the axis in the direction of application of force passing through the rigid center of the seismic isolation structure 1 (shown as a dashed line in Figures 1 and 2). The direction of application of force is the direction in which tensile force is applied by the retraction jacks 23 (described later) of the evaluation system 20 (shown as arrows in Figures 1 and 2).

[0043] This allows multiple evaluation systems 20 to cause the superstructure 2 and substructure 4 of the seismic isolation structure 1 to undergo relative displacement parallel to axis C. Therefore, it is possible to cause vibration parallel to axis C (in this case, along the X direction), and the period can be measured accurately.

[0044] Furthermore, it is desirable that the evaluation system 20 (specifically, the retraction jacks 23) be configured in the required number (number of units) according to the total amount of tensile force required. For example, if one unit is sufficient, one unit in the center of Figure 1 (at the position of axis C) may suffice, or if two units are needed, they should be arranged symmetrically with respect to axis C. If the total amount of tensile force required is large, four or more units may be provided, arranged symmetrically with respect to axis C. This allows for the generation of the tensile force necessary for the relative displacement of the superstructure 2 and the substructure 4. Thus, the relative displacement of the superstructure 2 and the substructure 4 can be reliably achieved.

[0045] As shown in Figure 3A, the evaluation system 20 includes a substructure side base 21, a superstructure side base 22, a retractable jack 23, a gripping device 24, PC steel strands 26, and an accelerometer 27.

[0046] As shown in Figures 1 and 3A, the base portion 21 on the substructure side is fixed between the adjacent seismic isolation lower foundations 4A. As a result, the base portion 21 on the substructure side is immovable relative to the substructure 4.

[0047] Furthermore, as shown in Figure 3A, the lower structure base 21 is constructed by stacking and joining steel materials, such as H-shaped steel, in the Z direction. As a result, as shown in Figures 2 and 3A, the lower structure base 21 is formed to the same height as the upper structure base 22. In this embodiment, a retraction jack 23 is fixed to the lower structure base 21, and the lower structure base 21 becomes the reaction force point when the evaluation system 20 is retracted (tensile force is applied) by the retraction jack 23.

[0048] As shown in Figures 2 and 3A, the superstructure-side base 22 is provided so as to surround the seismic isolation upper foundation 2A (with a planar shape resembling a square). In other words, the superstructure-side base 22 is fixed to the superstructure 2. In this embodiment, the superstructure-side base 22 is the point of application when the retraction jack 23 of the evaluation system 20 is used to retract (apply tensile force).

[0049] The retractable jack 23 (corresponding to a tensile force application device) is a device that applies a tensile force in a predetermined direction (here, one direction in the X direction (arrow direction in Figures 1 and 2)) between the base 21 on the lower structure side and the base 22 on the upper structure side, and is, for example, a retractable hydraulic jack. As mentioned above, the retractable jack 23 has the base 21 on the lower structure side as the point of reaction force and is fixed to the base 21 on the lower structure side. The retractable jack 23 then pulls in (pulls) the PC steel strand 26, one end of which is fixed to the base 22 on the upper structure side, via the grip device 24.

[0050] The grip device 24 (corresponding to a tensile force restraining device) is a device that restrains the tensile force of the retractable jack 23 and is connected to the tip of the retractable jack 23. The grip device 24 is also positioned to be movable relative to the base 21 on the lower structure side (for example, here, as shown in Figure 3A, a wheel is provided at the lower end of the grip device 24 to make it movable). As a result, the grip device 24 also moves in the X direction in accordance with the operation of the retractable jack 23.

[0051] Furthermore, the gripping device 24 has a gripping portion 24a. The gripping portion 24a is, for example, a hydraulic jack, which moves in the Z direction (up and down) according to the hydraulic pressure. By lowering the gripping portion 24a as shown in Figure 3C, the PC steel strand 26 can be gripped by sandwiching it between the opposing portion (the PC steel strand 26 is pressed by the hydraulic jack). By gripping (pressing) the PC steel strand 26 with the gripping portion 24a in this way, the tensile force of the retraction jack 23 is restrained. When the gripping portion 24a is raised, the grip on the PC steel strand 26 is released.

[0052] One end of the PC steel strand 26 (corresponding to a tension member) is attached (fixed) to the superstructure side base 22. In other words, the superstructure side base 22 has the PC steel strand 26.

[0053] Furthermore, the other end of the PC steel strand 26 is gripped by the gripping portion 24a of the gripping device 24 and connected to the base portion 21 on the substructure side via the retractable jack 23.

[0054] <Period measurement method> FIG. 4 is a flowchart showing the period measurement method by the evaluation system 20 of the present embodiment. Here, the evaluation system 20 functions as a period measurement system. FIGS. 5A to 5C are diagrams showing a state in which a tensile force is applied by the draw-in jack 23. FIGS. 6A to 6C are diagrams showing a state in which the application of the tensile force by the draw-in jack 23 is released. Each of FIGS. 5A to 5C and FIGS. 6A to 6C shows a diagram of a corresponding part to FIGS. 3A to 3C. Hereinafter, the period measurement method will be described using these figures.

[0055] First, as shown in FIGS. 3A to 3C, the wire 26 is gripped by the gripping portion 24a of the gripping device 24 from the PC steel (FIG. 4: S001). At this time, the length of the jack portion of the draw-in jack 23 is set as La as shown in FIG. 3B. Further, the length of the wire 26 from the PC steel between the upper structure side base 22 and the gripping portion 24a is set as Lb.

[0056] Next, the draw-in jack 23 is operated to draw in the gripping device 24 (in other words, the wire 26 from the PC steel) in the X direction (the arrow direction in FIGS. 1 and 2) (FIG. 4: S002). As a result, the length of the jack portion of the draw-in jack 23 becomes La´ (<La) as shown in FIG. 5B. Further, since the gripping portion 24a of the gripping device 24 grips the wire 26 from the PC steel, the upper structure side base 22 is also pulled in the tensile direction (X direction). As shown in FIG. 5B, at this time, the length of the wire 26 from the PC steel between the upper structure side base 22 and the gripping portion 24a is Lb (no change from the case of FIG. 3B).

[0057] Thereby, with the lower structure side base 21 as a reaction force, the upper structure side base 22 (that is, the upper structure 2) is pulled in the tensile direction (here, the X direction). Therefore, as shown in FIG. 5A, the upper structure 2 moves (relative displacement) with respect to the lower structure 4, and the seismic isolation device 10 undergoes shear deformation.

[0058] Next, when the relative displacement between the superstructure 2 and the substructure 4 reaches a predetermined displacement, the gripping portion 24a releases its grip on the PC steel strand 26, as shown in Figure 6C (Figure 4: S003). This releases the PC steel strand 26 from the gripping portion 24a. In Figure 6B, the length of the PC steel strand 26 between the superstructure base portion 22 and the gripping portion 24a is Lb' (>Lb). However, the PC steel strand 26 may also come out of the gripping portion 24a. As the PC steel strand 26 is released from the gripping portion 24a, the connection between the superstructure 2 and the substructure 4 is severed, and the superstructure 2 vibrates freely in the X direction, as shown in Figure 6C.

[0059] The period of this free vibration is measured using an accelerometer 27 (Figure 4: S004). This allows for the simple and accurate measurement of the period (natural period) of the seismic isolation structure 1 without removing the seismic isolation device 10 from the seismic isolation structure 1.

[0060] <Regarding methods for checking rigidity> Figure 7 is a flowchart showing the method for verifying rigidity using the evaluation system 20 of this embodiment. Note that the accelerometer 27 is not used (and may not be provided) for verifying rigidity.

[0061] First, similar to the period measurement method, the PC steel strand 26 is gripped by the gripping portion 24a of the gripping device 24 (S011).

[0062] Next, a tensile force is applied by the retraction jack 23, pulling the grip device 24 (in other words, the PC steel strand 26) in the X direction (S012).

[0063] At this time, the tensile force of the retraction jack 23 and the relative displacement between the lower structure 4 and the upper structure 2 are measured (S013).

[0064] Then, stiffness is confirmed from the tensile force and relative displacement (S014).

[0065] In this case as well, the rigidity (horizontal rigidity) of the seismic isolation structure 1 can be measured simply and accurately. Furthermore, the deformation and tensile force may be measured during the periodic measurement process described above.

[0066] <<Variation>> Figure 8 is an explanatory diagram of the modified evaluation system 20A.

[0067] In this modified example, an evaluation system 20A is provided. The evaluation system 20A has a base portion 21A on the lower structure side.

[0068] The substructure side base 21A, like the superstructure side base 22, is provided so as to surround the base isolation lower foundation 4A (with a planar shape resembling a square). A retraction jack 23, a grip device 24, and PC steel strands 26 are provided between the substructure side base 21A and the superstructure side base 22. In other words, in this modified example, the retraction jack 23, grip device 24, PC steel strands 26, etc., are arranged at an angle to the horizontal plane. Furthermore, the direction of retraction by the retraction jack 23 is also at an angle.

[0069] In this modified example, stiffness verification and period measurement can be performed in the same manner as in the previously described embodiment. When pulling diagonally in this way, the force applied by the jack can be decomposed into horizontal and vertical components, and the stiffness can be calculated using the horizontal force and deformation.

[0070] ===Other=== The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit its interpretation. The present invention can be modified and improved without departing from its spirit, and it goes without saying that the present invention includes equivalents thereof.

[0071] In this embodiment, the rigidity and period of a seismic isolation structure 1 in which a seismic isolation device 10 is interposed between the superstructure 2 and the substructure 4 were evaluated, but the embodiment is not limited to this.

[0072] For example, it can be applied to vibration control devices such as TMDs (Tuned Mass Dampers). A TMD is a technology that uses a weight that synchronizes with the building's movement to suppress the building's vibrations, for example, by placing a weight at the top of the building. When applied to a TMD, the weight corresponds to the superstructure, and the building corresponds to the substructure. Furthermore, when applied to a TMD, it is not limited to checking whether or not the seismic isolation device has deteriorated, but it is also possible to check the performance of the TMD (whether or not it moves according to the design specifications) during the building's construction phase.

[0073] Furthermore, the evaluation system 20 of this embodiment is not limited to seismic isolation devices, but can also be applied to the performance evaluation (stiffness confirmation, period measurement) of other restoring devices (e.g., springs).

[0074] Furthermore, although PC steel strands 26 were used as the tension member in the above-described embodiment, the system is not limited to this. For example, PC steel bars or the like may also be used.

[0075] Furthermore, in the above-described embodiment, the base 22 on the upper structure side was used as the point of application of the tensile force by the retraction jack 23, and the base 21 on the lower structure side was used as the point of reaction, but the relationship between the point of application and the point of reaction may be reversed. Also, in the above-described embodiment, the grip device 24 was described as being connected to the jack tip of the retraction jack 23, but it may also be fixed to the retaining wall or lower structure and the PC steel strands may be pulled with a center hole jack. [Explanation of Symbols]

[0076] 1. Seismic isolation structure 2 Superstructure 2A Seismic isolation upper foundation 4 Substructure 4A Seismic isolation lower foundation 10. Seismic isolation device (restoration device) 11 Upper flange plate 12 Laminated rubber 13 Lower flange plate 20. Evaluation Systems (Stiffness Verification System, Period Measurement System) 21,21A Substructure side base 22 Superstructure side base 23. Retractable jack (tensile force application device) 24. Grip device (tensile force restraint device) 24a Gripping part 26 PC steel strands (tensile material) 27 Accelerometer

Claims

1. A method for confirming the rigidity of a structure having a restoring device installed between the substructure and the superstructure, The lower structure side base of the restoration device is installed on the lower structure side, The upper structure side base of the restoration device is installed on the upper structure side, A tensile force application device installed between the lower structure side base and the upper structure side base, Equipped with, The tensile force application device is activated with either the base of the substructure or the base of the superstructure as the reaction force point, and the other base of the substructure or the base of the superstructure as the point of application of the tensile force. The tensile force and the relative displacement between the substructure and the superstructure are measured to confirm the rigidity of the structure. A method for confirming the rigidity of a structure, characterized by the following features.

2. A method for measuring the period of a structure having a restoring device installed between a substructure and a superstructure, The lower structure side base of the restoration device is installed on the lower structure side, The upper structure side base of the restoration device is installed on the upper structure side, A tensile force application device installed between the lower structure side base and the upper structure side base, Equipped with, The tensile force application device is activated with either the base of the substructure or the base of the superstructure as the reaction force point and the other base of the substructure or the base of the superstructure as the point of application of the tensile force. When the relative displacement between the substructure and the superstructure reaches a predetermined displacement amount, the tensile force application by the tensile force application device is released, and the period of the structure is measured. A method for measuring the period of a structure, characterized by the following features.

3. A method for measuring the period of a structure according to claim 2, The device has a tensile force restraining device that restrains the tensile force applied by the tensile force application device, A method for measuring the period of a structure, characterized by the following features.

4. A method for measuring the period of a structure according to claim 3, The other of the lower structure side base or the upper structure side base has a tension member attached to one side of the lower structure side base or the upper structure side base, The tensile force restraining device has a gripping portion for gripping the tensile member, When the tensile force applying device pulls the tensile member, the release of the tensile force restraint by the tensile force restraint device is performed by releasing the tensile member at the gripping portion. A method for measuring the period of a structure, characterized by the following features.

5. A method for measuring the period of a structure according to claim 2, The number of tensile force applying devices required is set according to the total amount of tensile force required. A method for measuring the period of a structure, characterized by the following features.

6. A method for measuring the period of a structure according to claim 2, The tensile force application device is arranged symmetrically with respect to the axis of the force application direction passing through the rigid center of the structure. A method for measuring the period of a structure, characterized by the following features.

7. A structural rigidity verification system having a restoring device installed between the substructure and the superstructure, The lower structure side base of the restoration device is installed on the lower structure side, The upper structure side base of the restoration device is installed on the upper structure side, A tensile force application device installed between the lower structure side base and the upper structure side base, Equipped with, The tensile force applying device applies tensile force with either the base of the lower structure or the base of the upper structure as the reaction point and the other of the base of the lower structure or the base of the upper structure as the point of application. Based on the tensile force and the relative displacement between the substructure and the superstructure, the rigidity of the structure is confirmed. A structural rigidity verification system characterized by the following features.

8. A period measurement system for a structure having a restoring device (such as laminated rubber) installed between the substructure and the superstructure, The lower structure side base of the restoration device is installed on the lower structure side, The upper structure side base of the restoration device is installed on the upper structure side, A tensile force application device installed between the lower structure side base and the upper structure side base, Equipped with, The tensile force applying device applies tensile force with either the base of the lower structure or the base of the upper structure as the reaction point and the other of the base of the lower structure or the base of the upper structure as the point of application. When the relative displacement between the substructure and the superstructure reaches a predetermined displacement amount due to the tensile force, the tensile force applied by the tensile force application device is released, and the period of the structure is measured. A period measurement system for structures characterized by the following features.

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