Structure Evaluation System, Structure Evaluation Apparatus, and Structure Evaluation Method

Patent metadata

Field	Value
Publication number	US-2017336364-A1
Application number	US-201715454101-A
Country	US
Kind code	A1
Filing date	Mar 9, 2017
Priority date	May 17, 2016
Publication date	Nov 23, 2017
Grant date	—

Abstract

According to an embodiment, a structure evaluation system includes a plurality of AE sensors, a signal processor, a position locator, a velocity calculator, and an evaluator. The AE sensors detect an elastic wave generated from a structure. The signal processor extracts an AE signal including information on the elastic wave by performing signal processing on the elastic wave detected by the AE sensor. The position locator derives a wave source distribution indicating a distribution of sources of the elastic waves generated in the structure on the basis of the AE signals. The velocity calculator derives a propagation velocity of the elastic wave generated in the structure on the basis of the AE signal. The evaluator evaluates the soundness of the structure on the basis of the wave source distributions and the propagation velocity of the elastic waves.

First claim

1 . A structure evaluation system comprising:
a plurality of AE sensors configured to detect an elastic wave generated from a structure; a signal processor configured to perform signal processing on the elastic waves detected by the AE sensors to extract an AE signal including Information on the elastic waves; a position locator configured to derive a wave source distribution, indicating a distribution of wave sources of the elastic waves generated from the structure, on the basis of the AE signals; a velocity calculator configured to derive a propagation velocity of the elastic wave generated from the structure on the basis of the AE signal; and an evaluator configured to evaluate soundness of the structure on the basis of the wave source distribution and the propagation velocity of the elastic waves.

2 . The structure evaluation system according to claim 1 , wherein, on the basis of a reference value related to a density of the wave sources, the evaluator segments the wave source distribution into two regions, including a region in which the wave sources are sparsely arranged and a region hi which the wave sources are densely arranged, and evaluates a region in which the wave sources are sparsely arranged and the propagation velocity of the elastic wave is lower than a reference value related to the propagation velocity of the elastic wave as a region in which deterioration of the structure is the most advanced.

3 . The structure evaluation system according to claim 1 , wherein:
the velocity calculator derives a propagation velocity distribution indicating a distribution of the propagation velocity of the elastic waves by performing AE tomography analysis based on the AE signals; and the evaluator segments, on the basis of a reference value related to the propagation velocity of the elastic waves, the propagation velocity distribution into two regions, including a region in which the propagation velocity is high and a region in which the propagation velocity is low, and evaluates the region in which the wave sources are sparsely arranged and the propagation velocity is low as a region in which deterioration of the structure is the most advanced by using the wave source distribution and the propagation velocity distribution.

4 . The structure evaluation system according to claim 1 , wherein the evaluator evaluates each region of the structure as being in one of four phases, Sound, Intermediate deterioration I, Intermediate deterioration II, and Limit deterioration, derives an evaluation result distribution indicating to which phase among Sound, Intermediate deterioration I, Intermediate deterioration II, and Limit deterioration each of the regions of the structures corresponds, and outputs the derived evaluation result distribution.

5 . The structure evaluation system according to claim 2 , wherein the evaluator evaluates a region in which the wave sources are sparsely arranged and the propagation velocity of the elastic wave is higher than a reference value related to the propagation velocity of the elastic wave as a region in the Sound phase in which deterioration of the structure is least advanced.

6 . The structure evaluation system according to claim 1 , wherein the position locator derives the wave source distribution in which a distribution of the wave sources having an amplitude equal to or larger than a predetermined value is shown, on the basis of amplitude information of the elastic waves detected by the AE sensors.

7 . The structure evaluation system according to clams 6 , wherein the amplitude Information of the elastic wave is information on an amplitude of a first arrival wave of the elastic wave in each event detected by the AE sensors.

8 . The structure evaluation system according to claim 1 , wherein the elastic wave is generated from damage to a surface or an inside of the structure as a result of stress applied to the structure.

9 . A structure evaluation apparatus comprising;
a signal processor configured to perform signal processing on an elastic wave detected by a plurality of AE sensors, which are configured to detect an elastic wave generated from a structure, and extract an AE signal including information on the elastic wave; a position locator configured to derive a wave source distribution, indicating a distribution of wave sources of the elastic waves generated from the structure, on the basis of the AE signals; a velocity calculator configured to derive a propagation velocity of the elastic wave generated from the structure on the basis of the AE signal; and an evaluator configured to evaluate soundness of the structure on the basis of the wave source distribution and the propagation velocity of the elastic waves.

10 . A structure evaluation method comprising:
a signal processing step of deriving signal processing is performed on an elastic wave detected by a plurality of AE sensors, which are configured to detect an elastic wave generated from a structure, and an AE signal including information on the elastic wave is extracted; a position locating step of deriving a wave source distribution, indicating a distribution of wave sources of the elastic waves generated from the structure, is derived on the basis of the AE signals; a velocity calculating step of deriving a propagation velocity of the elastic wave generated from the structure is derived on the basis of the AE signal; and an evaluating step of deriving soundness of the structure is evaluated on the basis of the wave source distribution and the propagation velocity of the elastic waves.

Assignees

• Toshiba Kk
• Univ Kyoto

Inventors

• Watabe Kazuo
• Takamine Hidefumi
• SHIOTANI Tomoki

Classifications

• G01M5/0008

  of bridges · CPC title

• G01N29/4436

  with a reference signal (amplitude comparison G01N29/48) · CPC title

• G01N2291/0289

  Internal structure, e.g. defects, grain size, texture · CPC title

• G01N29/043

  in the interior, e.g. by shear waves · CPC title

• G01M5/0066

  by exciting or detecting vibration or acceleration (vibration testing of structures G01M7/00) · CPC title