Vibration analysis method

Abstract

To more rationally verify an analysis object that includes a first constituent element whose vibration characteristic is not identified.SOLUTION: A vibration analysis method is for analyzing an analysis object that includes a first constituent element whose vibration characteristic is not identified and a second constituent element whose vibration characteristic is identified. The vibration analysis method includes: identifying information on vibration characteristic of the first constituent element on the basis of the result of test for vibrating the first constituent element; identifying a first model for the first constituent element part by using information on identified vibration characteristic of the first constituent element; and analyzing the vibration of the analysis object by using the first model for the first constituent element part and a second model for the second constituent element.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vibration analysis method. [Background technology]

[0002] Vibration tests are sometimes conducted to check the seismic performance of non-structural components and equipment within a building. However, sometimes the target structure is too large to fit on the vibration table 3 of the vibration test machine, or even if it could be placed on the vibration table 3, it is not easy to carry out the vibration test. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-052304 Summary of the Invention [Problem to be solved by the invention]

[0004] Although desk studies have sometimes been performed instead of vibration testing, they generally require a lot of time. Instead, simulation analysis is sometimes performed to provide a more rational analysis method. However, the target of vibration analysis sometimes includes a component (first component) whose vibration characteristics have not been specified. In such cases, there is a need for a more rational verification of the analysis target that includes the first component whose vibration characteristics have not been specified.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a vibration analysis method that can more rationally verify an analysis object that includes a first component whose vibration characteristics are not specified. [Means for solving the problem]

[0006] (1) One aspect of the present invention for solving the above problem is a vibration analysis method for analyzing an object to be analyzed that includes a first component whose vibration characteristics are not specified and a second component whose vibration characteristics are specified, the vibration analysis method including: specifying information on the vibration characteristics of the first component based on the results of a test in which the first component is vibrated; specifying a first model of the first component part using the specified information on the vibration characteristics of the first component; and analyzing the vibration of the object to be analyzed using the first model of the first component part and the second model of the second component part. (2) In the vibration analysis method of one aspect described above, the method includes detecting residual vibrations of each of the components at the positions where the sensors are placed, using sensors placed in a portion of each of the components including the first component and the second component. (3) In one aspect of the vibration analysis method described above, information on the residual vibrations (natural frequencies or damping characteristics) of some of the components detected by a hammer impact test, a push-over test, or a pull-over test on the some of the components is included in the information on the vibration characteristics of the some of the components. (4) In one aspect of the vibration analysis method described above, information on the natural frequency or damping characteristics of some of the components detected by a vibration test or a swing test on the some of the components is included in the information on the vibration characteristics of the some of the components. (5) In the vibration analysis method according to the above aspect, information on the natural frequencies of some of the components detected by a vibration test on the some of the components is included. (6) In the vibration analysis method according to the above aspect, each of the components includes either a nonstructural member or equipment. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a vibration analysis method that can more rationally verify the seismic performance of non-structural members and facilities in a building. [Brief explanation of the drawings]

[0008] [Figure 1A] 1 is an explanatory diagram showing an application example of a vibration analysis system 1 according to an embodiment. [Figure 1B] 1 is an explanatory diagram showing an application example of a vibration analysis system 1 according to an embodiment. [Figure 1C] 1 is an explanatory diagram showing an example of an evaluation target of the vibration analysis system 1 according to an embodiment. [Figure 1D] 1A and 1B are diagrams illustrating examples of vibration characteristics of an object to be evaluated according to an embodiment. [Figure 2] 1 is a schematic configuration diagram of a vibration analysis system 1 according to an embodiment. [Figure 3] FIG. 10 is a diagram illustrating a procedure of an analysis process according to an embodiment. [Figure 4] FIG. 10 is a diagram for explaining an application example of a seismic test according to the embodiment. [Figure 5] 10A and 10B are diagrams for explaining an example of a vibration test result of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] A vibration analysis method to which a vibration analysis system according to an embodiment is applied will be described below with reference to the drawings. In the following description, components having the same or similar functions will be assigned the same reference numerals. Duplicate descriptions of those components may be omitted.

[0010] □A vibration analysis system, for example, evaluates the vibration characteristics (rigidity, damping, strength, etc.) of the entire system of non-structural components and equipment by combining the vibration characteristics of the individual components that make it up, and evaluates the seismic performance by simulating the entire system.

[0011] The following methods are used in the above "evaluation" process. This method does not require the pre-modeling (mathematical formulation) of the vibration characteristics of a part or the whole of the object to be evaluated, but instead uses data detected by vibration tests to estimate the vibration characteristics (response characteristics) of a part or the whole of the entire system, thereby evaluating its seismic performance. For example, to facilitate analysis, the object to be evaluated may be identified as a low-order model. When the characteristics change significantly depending on the state of the system, it may be difficult to reproduce the actual state of the system even if such an identification result is used. The method described in the following embodiment is suitable for such cases.

[0012] Hereinafter, application examples of the vibration analysis system 1 according to the embodiment will be described with reference to the drawings. 1A and 1B are explanatory diagrams showing an application example of a vibration analysis system 1 according to an embodiment. FIG. 1C is an explanatory diagram showing an example of the evaluation object 2 of the vibration analysis system 1 according to the embodiment. FIG. 1D is a diagram illustrating an example of vibration characteristics of the evaluation object 2 according to the embodiment.

[0013] FIG. 1A shows the evaluation target 2 of the vibration analysis system 1 of the embodiment placed on floor FL. FIGS. 1B and 1C show the evaluation target 2 of the vibration analysis system 1 of the embodiment placed on the shaking table 3. As shown in FIGS. 1A, 1B, and 1C, the evaluation target 2 of the embodiment is a device having a rectangular parallelepiped housing. As shown in FIG. 1B, this device is relatively large compared to the size of the shaking table 3. This device is divided into an upper device and a lower device, which are stacked in two tiers and fastened with bolts via connecting members. The upper device and the lower device have a common structure. Each housing houses the equipment of the device main body. Each housing is formed by combining a frame F and a panel PNL that closes the opening of the frame F. Therefore, the frame F has the rigidity to support the weight of the equipment of the device main body and the weight of the upper device.

[0014] The configuration of a vibration analysis system 1 according to an embodiment will be described with reference to FIG. FIG. 2 is a schematic diagram of the vibration analysis system 1 according to the embodiment. As shown in FIG. 2, the vibration analysis system 1 of this embodiment is configured by a computer device 10 such as a personal computer or a workstation, and has as its main components a processing unit 82, a data input unit 83, an output unit 84, and an operation unit 85.

[0015] The processing unit 82 includes a RAM (Random Access Memory) 86, a ROM (Read Only Memory) 87, a CPU (Central Processing Unit) 88, an interface (I / F) 89, and a bus BUS. The RAM 86, the ROM 87, the CPU 88, and the I / F 89 are connected to one another by the bus BUS.

[0016] The RAM 86 is made up of a volatile storage device and functions as a working area for the CPU 88, which temporarily stores computer programs and data used in the processing executed by the CPU 88. The ROM 87 is made up of a non-volatile storage device and stores computer programs and data used in the processing executed by the CPU 88.

[0017] The CPU 88 is configured by an arithmetic processing unit capable of executing a computer program. The CPU 88 loads the computer program stored in the ROM 87 into the RAM 86 and executes the computer program loaded into the RAM 86, thereby controlling the operation of the entire vibration analysis system 1.

[0018] The data input unit 83, output unit 84, and operation unit 85 are connected to the processing unit 82 via an I / F 89. The data input unit 83 constitutes input means for inputting test data, actual measurement data of the evaluation object 2, etc., which will be described later, to the CPU 88 of the processing unit 82. A data logger 9, which will be described later, is an example of the data input unit 83. The output unit 84 is constituted by an output device such as a display device or a printer, and constitutes output means for outputting various information in accordance with control signals from the CPU 88. The operation unit 85 is constituted by a keyboard, a mouse pointer, a numeric keypad, etc., and is configured to input operation input information from the operator to the CPU 88 of the processing unit 82.

[0019] As shown in Fig. 1C, the vibration analysis system 1 includes sensors S1 and S2 that detect vibrations. Each sensor (S1, S2) is disposed in a part of the evaluation object 2 (each component) and detects vibrations at the respective positions where it is disposed. The sensors S1 and S2 may detect any of acceleration, velocity, and displacement. Each of these sensors (S1, S2) detects the response of the device during a hammer impact test, a push-over test, or a pull-over test when the test is performed on some of the components of the device to be evaluated 2. Information on the natural frequency or damping characteristics of the some of the components detected by each of the sensors (S1, S2) is used as information on the vibration characteristics of the some of the components. For example, the results of evaluating the vibration characteristics of the device under evaluation 2 are shown in FIG. 1D. It was found that the device under evaluation 2 had the vibration characteristics shown in Figure 1D when stacked in two layers. The evaluation results indicate that this device has a primary natural frequency of approximately 4 to 5 Hz.

[0020] The analysis process of the embodiment will be described with reference to FIG. FIG. 3 is a diagram illustrating a procedure of the analysis process according to the embodiment.

[0021] (Evaluation Overview) The procedure of the analysis process of the embodiment can be roughly divided into three stages as follows. In the first stage (STEP 1), an analysis is carried out using an analytical model. In the second stage (STEP 2), evaluation tests are conducted using the actual structure. In the third stage (STEP 3), the above analysis model is adjusted based on the results of evaluation tests using the actual structure. By appropriately repeating each of the above steps, the deviation between the response characteristics of the analytical model and the response characteristics of the actual structure is reduced. These will be explained in more detail below.

[0022] (Detailed evaluation procedure) The evaluation procedure will be explained in detail below.

[0023] · STEP 1: Vibration analysis is performed using the simulation model TM of the entire system T, which is used as the analysis model. The overall system T is formed by combining one or more components (objects) depending on the system configuration to be analyzed. The example shown in this figure is an example of a chiller, indoor equipment, etc. that make up an air conditioning system. A "simulation model TM" is a model for reproducing the vibration of each object. The vibration characteristics of this model may have nonlinearities related to the structure of each object and the magnitude of vibration.

[0024] For example, a model is defined that assumes that small-amplitude motion and large-amplitude motion occur depending on the environment (seismic motion amplitude). The vibration characteristics of this model are linear within the range of small-amplitude motion, but nonlinearity appears when the amplitude exceeds a predetermined value. Therefore, it is possible to approximate as a linear model within a range that reproduces vibration characteristics at small amplitudes, and it is preferable to approximate as a nonlinear model when the range is expanded to reproduce vibration characteristics at large amplitudes. By carrying out the procedure of STEP 1, the processing unit 82 can verify the range that can be treated as a linear model, the range that should be treated as a nonlinear model, and so on.

[0025] STEP 2: Tests to identify the vibration characteristics of the actual structure are carried out in the following three stages.

[0026] The processing unit 82 first performs a simple vibration measurement of another system (subsystem SA) that includes a component (partial element A) of the overall system T. Furthermore, if there is a shortage of data to be used for analysis processing, a vibration test will be carried out as necessary. In addition to simple vibration measurements and seismic tests, static tests on some of the removed components may be conducted to understand the vibration characteristics of individual components (subelement A).

[0027] Below, the process of STEP 2 will be further divided into three steps and explained.

[0028] STEP2-1: Simple vibration measurement (data collection for linearity evaluation) For example, the user installs sensors S1 and S2 (acceleration sensors) on the test specimen and connects the sensors S1 and S2 to the data logger 9. The processing unit 82 starts recording by the data logger 9, and records data on the vibrations detected by the sensors S1 and S2 during each test. The processing unit 82 continuously measures the microtremors of the test specimen for a predetermined period of time using the data logger 9. The predetermined period of time is set to, for example, 10 minutes. Next, the processing unit 82 manually vibrates the test specimen, and then uses the data logger 9 to measure the magnitude of the vibration (residual vibration) remaining in the test specimen. The processing unit 82 of the vibration analysis system 1 analyzes the acceleration data recorded in the data logger 9 and calculates the natural frequency and damping of the test specimen. For vibration analysis systems that can perform vibration tests using the shaking table 3, the processing unit 82 of the vibration analysis system 1 may compare and display, for example, the calculation results of the natural frequency and damping with the test results obtained using the shaking table 3. In this case, the processing unit 82 may specify the conditions for the vibration test to the controller 31 of the shaking table 3. The controller 31 can vibrate the shaking table 3 according to these instructions.

[0029] In the above-mentioned simple vibration measurement, the processing unit 82 obtains the vibration characteristics of another system (subsystem SA) at small amplitudes. From there, the processing unit 82 obtains the vibration characteristics of each component by performing a simulation or by introducing assumptions (for example, ignoring stiffness) about the vibration characteristics of other components of the component whose vibration characteristics are to be obtained. This allows the processing unit 82 to obtain vibration characteristics for analysis within a range in which linearity is ensured. Note that, since it is difficult to obtain data for analyzing nonlinearity from the vibration characteristics at small amplitudes, it is advisable to perform the following STEP 2-2, etc., as necessary.

[0030] STEP 2-2: Vibration measurement (data collection for nonlinearity evaluation) The processing unit 82 obtains the vibration characteristics of another system (subsystem SB) at large amplitudes during a large amplitude vibration test (seismic resistance test). From there, the processing unit 82 obtains the vibration characteristics of individual components by performing a simulation or introducing assumptions (for example, ignoring stiffness) about the vibration characteristics of other components of the component for which the vibration characteristics are to be obtained. Here, it is effective to obtain nonlinear characteristics of the vibration characteristics at large amplitudes from the physical configuration of the target structure. This allows the processing unit 82 to obtain vibration characteristics for analysis that go beyond the range in which linearity is ensured.

[0031] STEP2-3: The processor 82 adjusts the simulation model of the entire system and evaluates the seismic performance by simulation using the information obtained in STEP 2. If a static test on a component has been conducted, the processor 82 also reflects the results of the test in the adjustment.

[0032] STEP 3: Adjusting the analysis model Next, if necessary, based on the vibration characteristic data obtained in STEP 2, a simulation model (analysis model) of the entire system to be used in the simulation in STEP 1 is adjusted. This adjustment may be applied when the difference between the evaluation result in the real space and the simulation result exceeds a predetermined magnitude. The processing unit 82 may use this result to carry out simulations under various conditions in step 1.

[0033] An example of adjusting an analytical model using the results of a vibration test will be described with reference to Figures 4 and 5. For example, it is advisable to use the results of this vibration test to adjust the vibration characteristics of the relevant part of the overall model. FIG. 4 is a diagram for explaining an example of a vibration test result of the embodiment. FIG. 5 is a diagram for explaining the results of a seismic test of the embodiment.

[0034] The traces in the graph in Figure 4 show the relationship between displacement (horizontal axis) and shear force (vertical axis) obtained from the results of the vibration test. The following points can be read from the vibration test results: The stiffness changes depending on the amplitude. For example, the initial stiffness is maintained up to a deformation amount X of 3 mm, and the stiffness decreases by about 35%. The graph trajectory is close to bilinear, which is similar to the behavior of a general friction damper.

[0035] From these results, it can be inferred that factors such as those shown in Figure 5 are influencing the results. FIG. 5 shows the relationship between a deformable rectangular frame F and a panel PNL placed in an opening of the frame F. Figure 5(a) shows the state when there is a relatively small deformation, Figure 5(b) shows the state when there is a deformation larger than the deformation in Figure 5(a), and Figure 5(c) shows the state when there is a relatively small range of deformation larger than the deformation in Figure 5(a).

[0036] The range of the deformation amount X in FIG. 5(a) is defined as, for example, ±3 mm or less. The range of deformation amount X in Fig. 5(b) is defined as exceeding ±3 mm and not exceeding ±20 mm. When deformation reaches this range, large amplitude movement occurs. The range of deformation amount X in Figure 5(c) is defined as the range exceeding ±20 mm. When deformation reaches this range, large amplitude operation and saturation operation occur. This "deformation amount X" is defined as follows: Frame F is formed by a base BS and a pair of columns P and beams BM. The magnitude of the strain generated in frame F is defined as the horizontal distance between the top end of a certain column P and a vertical line based on the bottom end of that column P.

[0037] The panel PNL is formed to have a predetermined thickness and a predetermined strength. The frame F in which the panel PNL is placed in the opening is formed by a base BS, a pair of columns P provided on the base BS, and a beam BM provided between the pair of columns P. This panel PNL is supported by a base BS and a pair of columns P and beams BM, with its periphery surrounded. There is a clearance between the panel PNL and the column P.

[0038] A skeleton curve such as that shown in Figure 4 can be read. Furthermore, when deformation occurs in the frame F, the rectangle formed by the base BS and the pair of columns P and beams BM becomes distorted and turns into a parallelogram. As shown in FIG. 5(a), if the deformation amount of the frame F is within the range of X, the panel PNL does not slide on the base BS and does not move relative to the frame F. As shown in Figure 5(b), if the deformation amount of the frame F is within the range of X, the panel PNL will slide on the base BS. This will reduce the rigidity. Note that if the deformation amount is within this range, the clearance between the frame F and the panel PNL will not be reached. As shown in Figure 5(c), when the deformation of frame F reaches X, the clearance between frame F and panel PNL is reached, and the apparent rigidity increases. In addition, the horizontal movement of panel PNL is restricted by column P of frame F. It is advisable to reflect such characteristics in the vibration characteristics of the relevant part of the overall model.

[0039] The above explanation of the analysis example summarizes the relationship between a set of frame F and panel PNL, but by analyzing each part of the device in the above manner, the vibration characteristics of the entire model can be set more accurately.

[0040] According to the above embodiment, the vibration analysis method in the vibration analysis system 1 is a vibration analysis method for analyzing an analysis object that includes a first component whose vibration characteristics are not specified and a second component whose vibration characteristics are specified. The vibration analysis method includes: specifying information on the vibration characteristics of the first component based on the results of a test in which the first component is vibrated; specifying a first model of a portion of the first component using the specified information on the vibration characteristics of the first component; and analyzing the vibration of the analysis object using the first model of the first component part and the second model of the second component part.

[0041] For example, the vibration analysis system 1 detects vibrations of each component at the position where the sensor is placed on a part of each component, including the first component and the second component.

[0042] In addition, the vibration analysis system 1 may process information on the natural frequency or damping characteristics of some of the components detected by a hammer impact test, a push-over test, or a pull-over test on the some of the components, by including the information on the vibration characteristics of the some of the components.

[0043] In addition, the vibration analysis system 1 may process information on the natural frequency or damping characteristics of some of the components detected by vibration tests or swing tests on the some of the components, by including the information on the vibration characteristics of the some of the components.

[0044] Furthermore, the vibration analysis system 1 may also process information on the natural frequencies of some of the components detected by a vibration test on the some of the components.

[0045] In the vibration analysis system 1 of the above embodiment, the components of the analysis target include nonstructural members and equipment, the analysis target is divided into multiple components, and the seismic performance of the analysis target is derived based on the vibration characteristics of each component of the analysis target. The vibration analysis system 1 includes a processing unit that acquires information on the vibration characteristics of some of the components of the analysis target and generates a model that indicates the vibration characteristics of the analysis target based on the vibration characteristics of each component in accordance with predetermined rules. This makes it possible to more rationally verify the seismic performance of nonstructural members and equipment in a building.

[0046] By using such a vibration analysis system 1, the following effects are achieved. By combining the vibration characteristics of each component, it becomes possible to evaluate with high accuracy the vibration characteristics of the entire system, which is the evaluation target 2. By conducting both simple vibration measurements and seismic tests on the components, it is possible to obtain the vibration characteristics of the entire system of Evaluation Object 2 from small to large amplitudes. -Sufficient seismic performance can be ensured without conducting seismic testing of the entire system. The above simple test applies shock and vibration (disturbance) to evaluation object 2, and by analyzing the behavior of evaluation object 2 at this time, it is possible to estimate the vibration characteristics (frequency response, etc.) of evaluation object 2. Once the vibration characteristics of evaluation object 2 are determined, it will be possible to simulate the behavior of the structure when subjected to complex disturbances (such as earthquake motion).

[0047] Although one embodiment of the present invention has been described above, the embodiment of the present invention is not limited to the above. For example, the techniques exemplified in each embodiment and its modified examples may be combined in a manner other than the exemplified combinations. Furthermore, the embodiment of the present invention may be the following modified version of the above embodiment. [Explanation of symbols]

[0048] 1...Vibration analysis system 9...Data logger 10...Computer equipment 82...Processing section S1, S2...Sensor

Claims

1. 1. A vibration analysis method for analyzing an analysis object including a first component whose vibration characteristics are not specified and a second component whose vibration characteristics are specified, comprising: Identifying information about vibration characteristics of the first component based on the results of a test in which the first component is vibrated; identifying a first model of the first component part using information on the vibration characteristics of the identified first component; Analyzing vibrations of the analysis object using the first model of the first component part and the second model of the second component part. Vibration analysis method including:

2. By using a sensor disposed in a part of each of the components including the first component and the second component, residual vibration of each of the components is detected at the disposed position. The vibration analysis method according to claim 1, comprising:

3. Information on the residual vibrations (natural frequencies or damping characteristics) of some of the components detected by a hammer impact test, a push-over test, or a pull-over test on the some of the components is included in the information on the vibration characteristics of the some of the components. The vibration analysis method according to claim 2 .

4. Information on the natural frequency or damping characteristics of some of the components detected by a vibration test or a swing test on the some of the components is included in the information on the vibration characteristics of the some of the components. The vibration analysis method according to claim 2 .

5. Include information on the natural frequencies of some of the components detected by vibration tests on the some of the components. The vibration analysis method according to claim 2 or 3.

6. Each of the components includes either a non-structural member or equipment. The vibration analysis method according to claim 2 or 3.

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