Vibration test system and vibration test method

Abstract

To provide a vibration test system capable of generating a vertical vibration component that is greater than a vertical vibration component that can be generated by a vibration table.SOLUTION: A vibration test system provided herein vibrates an object under test by vibrating a vibration table at least in the vertical direction. The vibration test system comprises an amplification device configured to be vibrated by the vibration of the vibration table, generate a vertical vibration component greater than a vertical component of the vibration generated by the vibration table in response to the vibration of the vibration table, so as to vibrate an object under test.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration testing system and a vibration testing method. [Background technology]

[0002] The vibrations that a shaking table can output are limited to ranges determined by the frequency, acceleration, velocity, displacement, etc. Earthquake resistance tests using a shaking table are conducted under conditions within these ranges. In recent years, earthquake motions that exceed the range of vibrations that can be output by a shaking table have been observed. Meanwhile, there is known technology relating to a resilient strut with an integral hydraulic resonator for use in a rotorcraft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Publication No. 01-312244 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it is generally difficult to generate acceleration, velocity, and displacement that exceed the performance (maximum performance) of a shaking table, and it has been desired to generate vibrations (acceleration, velocity, and displacement) that exceed the performance of the shaking table.

[0005] The present invention has been made in consideration of the above circumstances, and aims to provide a vibration testing system and a vibration testing method that can generate a vertical component of vibration that is greater than the vertical component of vibration that can be generated by a shaking table. [Means for solving the problem]

[0006] (1) To solve the above problems, one aspect of the present invention provides a vibration testing system that vibrates a test object by vibrating a vibration table at least in the vertical direction, and includes an amplifier that oscillates due to the vibration of the vibration table and generates a vibration with a vertical component that is greater than the vertical component of the vibration generated by the vibration table in response to the vibration of the vibration table, thereby vibrating the test object. (2) In the above vibration testing system, the amplification device includes a base that oscillates due to the vibration of the vibration table, extends horizontally, and on which a test object is placed at a predetermined position; a first support part that includes a first columnar body fixed to the upper surface of the vibration table and supports the vicinity of a first end of the base in the extension direction while being in contact with the vicinity of the first end via a first buffer member; and a second support part that includes a second columnar body fixed to the upper surface of the vibration table and supports the vicinity of a second end of the base in the extension direction, and generates lateral vibrations with a vertical component that is larger than the vertical component of the vibration generated by the vibration table in the middle of the extension direction of the base in response to the vibration of the vibration table. (3) In the vibration testing system described above, the base has a first pressing surface along the vertical direction and the extension direction of the base, the first support part has a second pressing surface facing the first pressing surface near the first end part, and a first buffer member is arranged between the first pressing surface and the second pressing surface. (4) In the vibration testing system described above, the first end of the frame has a first surface that intersects with the extension direction of the frame, and the first surface contacts a second buffer member and receives stress due to compressive deformation of the second buffer member caused by vertical vibration of the frame. (5) In the vibration testing system described above, the base has a third pressing surface along the vertical direction and the extension direction of the base, the second support part has a fourth pressing surface facing the third pressing surface near the first end, and a viscoelastic body is arranged between the third pressing surface and the fourth pressing surface. (6) In the vibration testing system described above, the second support part includes a second columnar body fixed to the upper surface of the vibration table, and supports the vicinity of the second end of the frame in the extension direction while contacting the second end via a fourth buffer member. (7) In the vibration test system described above, the first support portion supports the vicinity of the first end portion with a pin, and the second support portion supports the vicinity of the second end portion with a pin. (8) In the vibration testing system described above, the second end of the frame has a second surface that intersects with the extension direction of the frame, and the second surface contacts the fourth buffer member and receives stress due to compressive deformation of the fourth buffer member caused by vertical vibration of the frame. (9) A vibration testing method according to one aspect of the present invention is a vibration testing method for a vibration testing system that vibrates a test object by vibrating a vibration table at least in a vertical direction, the vibration testing system being swung by the vibration of the vibration table, and generating vibrations with a vertical component that is greater than the vertical component of vibrations generated by the vibration table in response to the vibration of the vibration table, thereby vibrating the test object. [Effects of the Invention]

[0007] According to each aspect of the present invention, it is possible to generate a vibration with a vertical component that is greater than the vertical component that can be generated by a vibration table. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an explanatory diagram illustrating an overview of a vibration testing system according to an embodiment. [Figure 2] 3 is a configuration diagram of a first support portion 41 according to the embodiment. FIG. [Figure 3] 4A and 4B are diagrams for explaining an example of output characteristics of a vibrator according to an embodiment. [Figure 4] 10A and 10B are diagrams showing a comparison between vibrations generated by a vibrator including the vibration table 3 of the embodiment and vibrations obtained by amplification. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same or corresponding components are designated by the same reference numerals and the description thereof will be omitted as appropriate.

[0010] 1 is an explanatory diagram showing an overview of a vibration testing system 1 according to an embodiment of the present invention. The vibration testing system 1 shown in the figure vibrates a vibration table 3 at least in the vertical direction using a vibrator. The vibration test system 1 has an amplifier device 4 with a pedestal structure that amplifies vibrations (acceleration, velocity, displacement) generated in a test body 2. For example, the vibration test system 1 amplifies vibrations, particularly vertical vibrations, generated by a vibration table 3.

[0011] The amplifier 4 includes, for example, a first support section 41, a second support section 42, and a pedestal 43. The amplifier 4 includes, for example, one or more sets of the first support section 41, the second support section 42, and the pedestal 43. The configuration example shown in FIG. 1 is for the case of two sets, group A and group B.

[0012] For example, the first support portion 41 includes a first columnar body 411 fixed to the upper surface 3F of the vibration table. The second support portion 42 includes a second columnar body 421 fixed to the upper surface 3F of the vibration table. A base 43 is provided between the first support portion 41 and the second support portion . The base 43 is supported by the first support portion 41 and the second support portion 42 and oscillates due to the vibration of the vibration table 3. The base 43 extends in the horizontal direction, and the test specimen 2 is placed at a predetermined position. As a result, the test body 2 is vibrated by the swinging of the stand 43 .

[0013] A more detailed configuration example of the first support portion 41 will be described with reference to Fig. 2. Fig. 2 is a configuration diagram of the first support portion 41 according to the embodiment.

[0014] (First support part 41): The first support portion 41 supports the vicinity of the first end portion in the extension direction of the base 43 in a state of being in contact with the vicinity of the first end portion via the first buffer member. A first steel plate member 413 is provided on the upper end side of the first support portion 41. More specifically, on the upper end side of the square steel pipe forming the first columnar body 411 of the first support portion 41, there is provided a plate 412 that covers the opening at the upper end, and a first steel plate member 413 (gusset plate) that extends vertically from the plate 412.

[0015] The first steel plate member 413 has a through hole for supporting the mount 43 . A similar through hole is provided near the first end of the mount 43. The through hole of the mount 43 and the through hole of the first steel plate member 413 are connected via a common shaft 416 . The first buffer member 417 is provided so as to cover the outside of the periphery of the through hole.

[0016] (Second support part 42): The second support portion 42 supports the vicinity of a second end portion in the extension direction of the frame 43 in a state of contact with the second end portion via a second buffer member. A second steel plate member 423 (not shown) is provided on the upper end side of the second support portion . More specifically, on the upper end side of the square steel material forming the first columnar body 411 of the second support portion 42, there is provided a plate 412 that covers the opening at the upper end, and a second steel plate member 423 (gusset plate) that extends vertically from the plate 412.

[0017] The second steel plate member 423 has a through hole for supporting the frame 43 . A similar through hole is provided near the second end of the mount 43. The through hole of the mount 43 and the through hole of the second steel plate member 423 are connected via a common shaft. The first buffer member 427 is provided so as to cover the outside of the periphery of the through hole.

[0018] The vibration testing system 1 configured in this manner applies a predetermined vibration to the vibration table 3 to excite the amplifier 4, and in response to the vibration of the vibration table 3, generates a vibration of a larger amplitude in the middle of the extension direction of the frame 43 than the vibration applied by the vibration table 3 to the amplifier 4.

[0019] (Structure of first support portion 41) An example of the structure of the first support portion 41 of the amplifier device 4 will be described more specifically. A first reinforcing member 414 (rib plate) and a second reinforcing member 415 (rib plate) that reinforce the first steel plate member 413 are provided at the ends of the first steel plate member 413 in the width direction. The first reinforcing member 414 (rib plate) is provided at a first end of the first steel plate member 413 (gusset plate) at a position farther away from the axis 416 with respect to the center of the length of the frame 43 in the extension direction. The second reinforcing member 415 (rib plate) is provided at a second end of the first steel plate member 413 (gusset plate) at a position in the length of the extension direction of the frame 43, using the first steel plate member 413 (gusset plate) that is closer to the center of the length of the extension direction of the frame 43 than the axis 416.

[0020] The plate 412, the first steel plate member 413, the first reinforcing member 414 (rib plate), and the second reinforcing member 415 (rib plate) are welded together.

[0021] (Configuration example) 2 shows an example of the configuration of the first support portion 41. First columnar body 411 of first support part 41: square steel pipe 200x200x9 Plate 412 Thickness: 12mm First steel plate member 413 (gusset plate) thickness: 9 mm First reinforcing member 414, second reinforcing member 415 (rib plate) thickness: 6 mm Axis 416: Bolt M27

[0022] 1 shows an example of the configuration of the stand 43. Frame 43: H-beam 150x150x7x10 The above configuration example is an example, and is not limited to this and can be modified as appropriate. The second support portion 42 may also have a similar configuration to the first support portion 41.

[0023] (Structure of the connecting part) The structure of the linking portion will be described more specifically.

[0024] The base 43 has a first pressing surface (for example, the surface of the web of an H-beam) along the vertical direction and the extension direction of the base 43. The first support portion 41 has a second pressing surface that faces the first pressing surface near the first end portion. A viscoelastic body (first buffer member 417) is disposed between the first pressing surface and the second pressing surface of the first support portion 41. The second pressing surface of the first support portion 41 and the first pressing surface of the base 43 are disposed opposite to each other with the first buffer member 417 interposed therebetween. The base 43 is supported by a pin so as to be rotatable around a first shaft 416 .

[0025] The base 43 has a third pressing surface that is aligned in the vertical direction and in the extension direction of the base 43. The second support portion 42 has a fourth pressing surface that faces the third pressing surface near the second end portion. A viscoelastic body (third buffer member 427 (not shown)) is disposed between the third pressing surface and the fourth pressing surface. The fourth pressing surface of the second support portion 42 and the third pressing surface of the base 43 are disposed opposite to each other with a fourth buffer member 428 (not shown) interposed therebetween. The base 43 is supported by a pin so as to be rotatable about a second shaft 426 (not shown).

[0026] (Action of viscoelastic body) The viscoelastic body includes a first buffer member 417 and a second buffer member 418.

[0027] The first buffer member 417 of the first support portion 41 is disposed between the first pressing surface of the base 43 and the second pressing surface of the first support portion 41 . The second buffer member 418 of the first support portion 41 is disposed between the first end of the frame 43 in the extension direction and the first reinforcing member 414.

[0028] The first buffer member 417 and the second buffer member 418 may be configured as a single unit or as separate units. For example, the configuration can be simplified by configuring the first buffer member 417 and the second buffer member 418 as a single unit. It is preferable to allocate one viscoelastic body to the first buffer member 417 and the second buffer member 418 by bending it into an L shape. In contrast to this, by configuring them as separate bodies, the characteristics of first buffer member 417 and second buffer member 418 can be made different from each other.

[0029] For example, a first end of the frame 43 (for example, an end of a web of an H-beam) has a first surface that intersects with the extension direction of the frame 43. The first surface is in contact with the second buffer member 418 and receives stress due to compressive deformation of the second buffer member 418 caused by vibration of the base 43 in the up and down direction. Furthermore, a second end of the pedestal 43 (for example, the other end of the web of the H-shaped steel) may have a second surface that intersects with the extension direction of the pedestal 43. In this case, the second surface contacts a fourth buffer member (not shown) and receives stress due to compressive deformation of the fourth buffer member caused by vertical vibration of the pedestal 43. The configuration for supporting the second end side of the pedestal 43 may be the same as the configuration for supporting the pedestal 43 at the first end side.

[0030] (Amplification of vibrations by an amplifier) The amplifier 4 and the test specimen 2 are placed on the vibration table 3, and the vibration table 3 is vibrated in the Z direction (vertical direction). As the vibration table 3 moves up and down, transverse wave vibrations occur in the base 43, causing deflection of the base 43. When a vertical movement component is applied to the vibration table 3, the vibrations are amplified and the base 43 vibrates.

[0031] For example, the vibration of the vibration table 3 is set to a vibration force that, even if the vibration caused by the vibration is amplified, will not damage the test piece 2. For example, the vibration of the vibration table 3 is set to a random wave of a maximum of about 100 gal. Acceleration sensors S1, S2, S3, and S4 capable of detecting vibration components in the vertical direction are attached to the center of gravity of test body 2, the bottom of test body 2, the top of base 43, and vibration table 3, respectively, and the amplification factor for the vibration of vibration table 3 at each position of acceleration sensors S1, S2, and S3 is calculated. The vibration amplification factor is determined based on the data on the amplification factor at each position. For example, the above vibration amplification factor can be used to back-calculate how much acceleration should be input to the shaking table 3 to reproduce the desired vertical acceleration input to the test specimen 2. Based on the calculation results, the acceleration to be input to the shaking table 3 is determined and the actual test is carried out.

[0032] To fine-tune the amplification factor, it is a good idea to prepare viscoelastic materials with different viscosities (viscosities), and use a viscoelastic material with a high viscosity when you want to suppress the amplification factor.Even when adjusting the amplification factor in this way, it is a good idea to proceed with the test while checking the results of excitation using a random wave (vibration with a waveform in which it is difficult to identify regularities such as amplitude and frequency) of up to about 100 gal, and the amplification factor in that case.

[0033] It should be noted that when the viscosity of the viscoelastic body increases, the vertical movement of the end of the base 43 is suppressed, thereby reducing the amplification factor of the vibration.

[0034] An example of the characteristics of a vibration exciter including the vibration table 3 of the embodiment will be described with reference to FIG. FIG. 3 is a diagram illustrating an example of output characteristics of the vibrator according to the embodiment. As the output characteristics of the vibrator, an upper limit for the vertical component may be set as shown in Figure 3. This characteristic diagram shows the scales of frequency, displacement, velocity, and acceleration, and defines the range in which these vibration conditions are met. The vibration defined in this diagram is a single-frequency sine wave, but it can also be applied to mixed-wave vibrations. As shown in this characteristic diagram, the weight of the object loaded on the vibration table 3 also affects the upper limit value.

[0035] FIG. 4 is a diagram showing a comparison between vibrations generated by a vibrator including the vibration table 3 of the embodiment and vibrations obtained by amplification. As shown in this figure, it can be seen that the amplitude of the amplified vibration is greater than the amplitude of the vibration generated by the vibration exciter including the vibration table 3.

[0036] As can be seen from these measurement results, an amplifier 4 is formed by combining ordinary steel frames, bolts, and buffer materials, and the acceleration, velocity, and displacement are amplified by the amplifier 4. The amplification rate can be controlled by adjusting the rigidity around the axis provided by the buffer materials.

[0037] According to the above embodiment, in the vibration test system, a vibration table is vibrated at least in the vertical direction to vibrate the test specimen 2. The vibration test system includes an amplifier that sways due to the vibration of the vibration table, generates a vertical component of vibration that is larger than the vertical component of the vibration generated by the vibration table in response to the vibration of the vibration table, and transmits the generated vertical component to the test specimen 2. This makes it possible to generate a vertical component of vibration that is larger than the vertical component of vibration that can be generated by the vibration table. Furthermore, in response to the vibration of the vibration table, a lateral vibration having a vertical component greater than the vertical component of the vibration generated by the vibration table can be generated in the middle of the extension direction of the frame.

[0038] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents. [Explanation of symbols]

[0039] 1. Vibration Test System 2 Test specimen 3. Shaking table 4. Amplification equipment, 41 first support part, 42 second support part, 43 Mounting stand

Claims

1. A vibration test system for vibrating a test object by vibrating a vibration table at least in a vertical direction, comprising: an amplifier that vibrates the test object by generating a vibration component in a vertical direction that is greater than the vertical component of the vibration generated by the vibration table in response to the vibration of the vibration table, and vibrates the test object; A vibration test system comprising:

2. The amplifier device comprises: a stand that oscillates due to the vibration of the vibration table, extends in a horizontal direction, and allows a test specimen to be placed at a predetermined position; a first support portion including a first columnar body fixed to an upper surface of the vibration table, the first support portion supporting a vicinity of a first end portion of the frame in an extension direction while being in contact with the vicinity of the first end portion via a first buffer member; a second support portion including a second columnar body fixed to an upper surface of the vibration table and supporting a vicinity of a second end portion of the frame in an extension direction; Equipped with In response to the vibration of the vibration table, a lateral vibration having a vertical component greater than the vertical component of the vibration generated by the vibration table is generated in the middle of the extension direction of the frame.

10. The vibration testing system of claim 1.

3. the cradle includes a first pressing surface along a vertical direction and an extension direction of the cradle, the first support portion includes a second pressing surface facing the first pressing surface in the vicinity of the first end portion, A first buffer member is disposed between the first pressing surface and the second pressing surface.

3. The vibration testing system of claim 2.

4. the first end of the cradle has a first surface that intersects with the extension direction of the cradle; the first surface contacts the second buffer member; The second buffer member is subjected to stress due to compressive deformation caused by vertical vibration of the frame.

3. The vibration testing system of claim 2.

5. the cradle includes a third pressing surface along the vertical direction and an extension direction of the cradle, the second support portion includes a fourth pressing surface facing the third pressing surface in the vicinity of the second end portion, A viscoelastic body is disposed between the third pressing surface and the fourth pressing surface.

4. The vibration testing system of claim 3.

6. The second support portion is a second columnar body fixed to an upper surface of the vibration table, the second columnar body supporting a vicinity of a second end of the frame in an extension direction thereof in a state of contact with the second end of the frame via a fourth buffer member; 6. The vibration testing system of claim 5.

7. the first support portion is supported by a pin in the vicinity of the first end portion, The second support portion is supported by a pin near the second end.

3. The vibration testing system of claim 2.

8. the second end of the cradle has a second surface that intersects with the extension direction of the cradle; the second surface contacts the fourth buffer member, The fourth buffer member is subjected to stress due to compressive deformation caused by vertical vibration of the frame.

3. The vibration testing system of claim 2.

9. A vibration test method for a vibration test system in which a vibration table is vibrated at least in a vertical direction to vibrate a test object, comprising: vibrating the test object by the vibration of the vibration table, and generating vibrations greater than the vibration of the vibration table in response to the vibration of the vibration table to vibrate the test object; Vibration test method including:

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