CN-121612997-B - Concrete structure crack damage evaluation system based on acoustic emission sensing

CN121612997BCN 121612997 BCN121612997 BCN 121612997BCN-121612997-B

Abstract

The invention relates to the technical field of concrete detection, in particular to a concrete structure crack damage evaluation system based on acoustic emission sensing. According to the method, a multidimensional evolution set is constructed by extracting the amplitude of the acoustic emission signal in a continuous time window and the standard deviation of energy, a Bayesian probability model is utilized to analyze the synchronous variation trend of the standard deviation of multiple parameters, the non-uniform expansion posterior probability is calculated to lock a key signal set of dominant damage expansion, the energy fluctuation coefficient is calculated by combining the sensor space coordinates and a space sequence is generated, the fluctuation coefficient stability interval is identified according to the gradient attenuation rule of the energy along with the distance, so that the physical boundary of a crack damage dynamic active region is quantitatively defined, and the non-uniform expansion state and the accurate evaluation of the active range of a concrete crack are realized.

Inventors

SUN HAIRONG
HUANG XIN
LIU JINTAO
WANG TAO
HU GANG
MENG FANSHENG
LIU JIANHUA
Gong Mingun
Cui Tianhang
WANG JIANFENG
QI TINGTING
YIN HUI
WANG LISHI
ZHANG QUAN
QIN TONG

Assignees

成都嘉新科技集团有限公司

Dates

Publication Date: 20260512
Application Date: 20260202

Claims (8)

1. A concrete structure crack damage assessment system based on acoustic emission sensing, the system comprising: The signal acquisition module acquires elastic wave signals on the surface of the concrete structure, converts the elastic wave signals into a digital waveform data sequence, and intercepts acoustic emission waveform data segments in the digital waveform data sequence; the characteristic discrete evolution module extracts the amplitude, energy and duration of the acoustic emission waveform data segment, maps the amplitude, energy and duration to a time window, calculates a data mean value and standard deviation in the time window, and constructs a multi-parameter discrete evolution characteristic set; The probability inference module is used for setting prior probability of the non-uniform expansion possibility of the characterization area, calculating posterior probability of the concrete structure crack in the non-uniform expansion state by combining the change trend of the multi-parameter discrete evolution characteristic set, and marking a non-uniform expansion dominant signal set according to the posterior probability; The energy gradient analysis module is used for determining corresponding sensors of the non-uniform expansion dominant signal set in the acoustic emission sensor array, acquiring space coordinates among the corresponding sensors and acoustic emission source positioning coordinates, calculating energy fluctuation coefficients and generating an energy fluctuation coefficient sequence; The boundary definition module is used for identifying the boundary of the dynamic active region representing the crack damage of the concrete structure according to the change condition of the energy fluctuation coefficient in the energy fluctuation coefficient sequence; The probability inference module comprises: The trend direction judgment and statistics sub-module extracts standard deviations of a current time window and a preamble adjacent time window from the multi-parameter discrete evolution feature set, performs difference comparison on the standard deviations of the two adjacent windows, judges the increasing and decreasing change condition of numerical values, and counts the number of parameters which show synchronous increasing or synchronous decreasing trend in three parameters of amplitude, energy and duration to be used as the direction of the discrete parameter change trend; The posterior probability Bayes operator module is used for setting prior probability values representing the non-uniform expansion possibility of the region, constructing likelihood functions based on the discrete parameter variation trend direction, and carrying the prior probability and the likelihood functions into a Bayes statistical inference model to carry out multiplication and normalization operation to obtain non-uniform expansion posterior probability; The non-uniform leading signal marking submodule sets a reference probability threshold for judging state certainty, compares the non-uniform expansion posterior probability with the reference probability threshold, screens a time window exceeding the reference probability threshold, traces and locks the original waveform data associated with the time window, and marks the original waveform data as a non-uniform expansion leading signal set; the energy gradient analysis module comprises: The space distance mapping and sorting sub-module is used for identifying the corresponding response sensor numbers of the non-uniform expansion dominant signal set, calling corresponding sensor space coordinates from the acoustic emission sensor array, and calculating the linear distance between the sensor space coordinates and the acoustic emission source positioning coordinates to serve as the space distance from the sensor to the source end; the energy space segmentation sub-module is used for acquiring energy data corresponding to the non-uniform expansion dominant signal set, arranging the energy data in an ascending order according to the space distance from the sensor to the source end, cutting and distributing the ordered energy data into continuous spaces according to a preset distance interval step length, and generating a continuous space propagation segment; And the fluctuation coefficient sequence generation submodule calculates the average value of the energy data in each continuous space propagation section, simultaneously searches the maximum value and the minimum value of the energy in the continuous space propagation section, calculates the difference value, calculates the energy fluctuation coefficient according to the ratio of the difference value to the average value, and constructs the energy fluctuation coefficient sequence.
2. The acoustic emission sensing-based concrete structure crack damage assessment system according to claim 1, wherein the acoustic emission waveform data segment is specifically a data sequence of a specified length after a triggering time, which is intercepted from a digital waveform data sequence, the multi-parameter discrete evolution feature set comprises an amplitude standard deviation, an energy standard deviation and a duration standard deviation calculated for each continuous time window, the non-uniform expansion dominant signal set is specifically a set of acoustic emission waveform data segments associated with a time window with a posterior probability higher than a decision reference probability, the energy fluctuation coefficient sequence comprises a dimensionless energy fluctuation coefficient calculated for each spatial propagation section, and the boundary of the concrete structure crack damage dynamic active region is specifically a starting distance value of a spatial propagation section closest to an acoustic emission source positioning coordinate in an energy attenuation stable region.
3. The acoustic emission sensing based concrete structure crack damage assessment system of claim 1, wherein the signal acquisition module comprises: the elastic wave capturing and converting sub-module is used for acquiring an acoustic emission sensor array arranged on the surface of the concrete structure, monitoring mechanical vibration waves generated in the stress process of the concrete structure in real time, collecting the mechanical vibration waves and taking the mechanical vibration waves as initial signals, setting sampling frequency and quantization bits to perform conversion from analog signals to digital signals on the initial signals, arranging converted values in time sequence, and generating a digital waveform data sequence; The trigger moment scanning and identifying sub-module sets a background noise reference value for distinguishing the attribute of the initial signal, scans the voltage amplitude in the digital waveform data sequence point by point according to the time step, compares the voltage amplitude with the background noise reference value, locates a time node of which the first voltage amplitude exceeds the background noise reference value, marks the initial position of the waveform arrival, and obtains the digital waveform trigger moment; And the waveform data interception and storage sub-module is used for positioning the digital waveform trigger time and the subsequent time interval on the time axis of the digital waveform data sequence, setting waveform interception length parameters, intercepting all digital points in the waveform interception length parameter range after the trigger time and generating an acoustic emission waveform data segment.
4. The acoustic emission sensing based concrete structure crack damage assessment system of claim 3, wherein the characteristic discrete evolution module comprises: The basic parameter analysis and extraction submodule analyzes the waveform structure of the acoustic emission waveform data segment, traverses waveform data points from the waveform data points to search the maximum point of the voltage absolute value as amplitude data, performs envelope detection operation on the acoustic emission waveform data segment to construct a waveform envelope, performs time integration operation on the waveform envelope to obtain an area value as energy data, detects the time difference between the first and last voltage threshold crossing of the waveform as duration data, and obtains a waveform basic parameter set; the window statistical average value calculation sub-module maps the amplitude, energy and duration data into a plurality of continuous time windows with preset lengths according to time sequence according to the generation time stamp of the amplitude, energy and duration data in the waveform basic parameter set, extracts all the amplitude, energy and duration data in each independent time window respectively, and calculates respective average values to obtain window parameter average value information; the discrete feature set construction submodule calculates standard deviation between the amplitude, energy and duration data in each independent time window and the corresponding respective average value in the window parameter average value information respectively, combines and arranges the standard deviation of a plurality of dimensions, and generates a multi-parameter discrete evolution feature set.
5. The acoustic emission sensor based concrete structure crack damage assessment system of claim 4, wherein performing an envelope detection operation on the acoustic emission waveform data segment to construct a waveform envelope comprises: Acquiring a time domain discrete voltage value sequence formed by acoustic emission waveform data segments; invoking a fast Fourier transform algorithm to perform mapping processing from a time domain to a frequency domain on the time domain discrete voltage numerical value sequence to obtain a frequency domain signal sequence; identifying positive frequency components and negative frequency components in the frequency domain signal sequence; Zeroing the numerical value of the negative frequency component, and calculating an adjusted single-side frequency spectrum sequence according to the positive frequency component and a preset weighting proportion coefficient; invoking a fast Fourier inversion algorithm to perform inverse transformation processing on the single-sided frequency spectrum sequence to generate a complex-form analysis signal sequence; separating corresponding real part data values and imaginary part data values for each sampling time in the analysis signal sequence; calculating a real part square value according to the real part data value, and calculating an imaginary part square value according to the imaginary part data value; calculating a modulus square sum value according to the real square value and the imaginary square value; calculating the instantaneous amplitude value of the analysis signal sequence at the sampling moment according to the module square sum value; And sequentially connecting the instantaneous amplitude values corresponding to all the sampling moments according to the time sequence to generate a waveform envelope.
6. The acoustic emission sensing-based concrete structure crack damage assessment system of claim 1, wherein for the non-uniform expansion posterior probability, the formula is used: ; Wherein, the In order to observe the posterior probability of the non-uniform expansion E under the condition of the current multi-parameter standard deviation synchronous change state H, For the a priori probability that non-uniform expansion occurs, To observe the likelihood probability of a multiparameter standard deviation synchronous change state H when non-uniform expansion occurs, To observe the likelihood probability of a multiparameter standard deviation synchronous change state H when no non-uniform expansion occurs, The state intensity weight factors are synchronously changed for the multi-parameter standard deviation.
7. The acoustic emission sensing based concrete structure crack damage assessment system of claim 1, wherein calculating a linear distance between sensor spatial coordinates and acoustic emission source location coordinates comprises: Respectively acquiring a transverse coordinate component, a longitudinal coordinate component and a vertical coordinate component of a sensor space coordinate and an acoustic emission source positioning coordinate under a three-dimensional space rectangular coordinate system; Respectively calculating corresponding coordinate difference square values according to the transverse coordinate component, the longitudinal coordinate component and the vertical coordinate component; And calculating a space distance square sum value according to the coordinate difference square value corresponding to the three dimensions, and performing open square operation on the space distance square sum value to obtain a linear distance.
8. The acoustic emission sensing based concrete structure crack damage assessment system of claim 1, wherein the boundary definition module comprises: Scanning the energy fluctuation coefficient sequences item by item along the distance increasing direction by the coefficient stabilization interval primary screen module, checking whether three adjacent energy fluctuation coefficients in the sequences are lower than a preset stabilization judgment threshold value, and recording the position indexes of the corresponding energy fluctuation coefficients in the energy fluctuation coefficient sequences to obtain candidate stabilization area indexes; The gradient attenuation condition verification submodule extracts the continuous space propagation sections corresponding to the candidate stable region indexes, calculates average energy difference between the continuous space propagation sections, compares the average energy difference with a preset gradient threshold value, confirms that energy attenuation tends to be gentle if the average energy difference is smaller than the gradient threshold value, and generates an energy attenuation stable region; And the active region boundary positioning sub-module is used for searching all continuous space propagation sections in the energy attenuation stable region, identifying one space propagation section closest to the acoustic emission source positioning coordinates, extracting the starting distance of the corresponding space propagation section, defining the starting distance as a boundary point between the crack damage dynamic active region and the stable region, and generating the crack damage dynamic active region boundary of the concrete structure.

Description

Concrete structure crack damage evaluation system based on acoustic emission sensing Technical Field The invention relates to the technical field of concrete detection, in particular to a concrete structure crack damage evaluation system based on acoustic emission sensing. Background The technical field of concrete detection refers to a technical set developed around the state identification and performance judgment of concrete materials and concrete structures in the production construction and service processes, and comprises detection analysis and evaluation of the crack damage evolution of the internal defects of the concrete and the structural safety state, and the technical set generally relates to the extraction of physical meter characterization features, the state judgment and the like of sensor arrangement signal acquisition. The system for evaluating the crack damage of the concrete structure is a system for analyzing and judging the degree and distribution of the crack damage by arranging acoustic emission sensors on the surface or inside of a concrete member, collecting elastic wave signals generated by crack initiation and expansion and damage development in the loading process of the concrete, counting parameters such as energy duration time and arrival sequence according to the amplitude value of an acoustic emission event. The existing evaluation means only depend on basic statistical parameters such as amplitude, energy and the like of acoustic emission events to judge the damage degree, dynamic change characteristics of discrete degrees of signals in a time sequence evolution process are ignored, a critical state of transition of a crack from uniform micro damage to non-uniform expansion is difficult to capture, key signals leading crack expansion cannot be accurately stripped, energy gradient attenuation analysis on a high-risk signal in a space dimension is lacking, boundary definition of a dynamic active region of crack damage is fuzzy, quantitative evaluation indexes reflecting non-uniform expansion trend of the crack cannot be constructed, and accuracy of crack risk region identification is lowered. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a concrete structure crack damage evaluation system based on acoustic emission sensing. In order to achieve the above purpose, the invention adopts the following technical scheme that the concrete structure crack damage evaluation system based on acoustic emission sensing comprises: The signal acquisition module acquires elastic wave signals on the surface of the concrete structure, converts the elastic wave signals into a digital waveform data sequence, and intercepts acoustic emission waveform data segments in the digital waveform data sequence; the characteristic discrete evolution module extracts the amplitude, energy and duration of the acoustic emission waveform data segment, maps the amplitude, energy and duration to a time window, calculates a data mean value and standard deviation in the time window, and constructs a multi-parameter discrete evolution characteristic set; The probability inference module is used for setting prior probability of the non-uniform expansion possibility of the characterization area, calculating posterior probability of the concrete structure crack in the non-uniform expansion state by combining the change trend of the multi-parameter discrete evolution characteristic set, and marking a non-uniform expansion dominant signal set according to the posterior probability; The energy gradient analysis module is used for determining corresponding sensors of the non-uniform expansion dominant signal set in the acoustic emission sensor array, acquiring space coordinates among the corresponding sensors and acoustic emission source positioning coordinates, calculating energy fluctuation coefficients and generating an energy fluctuation coefficient sequence; And the boundary definition module is used for identifying the boundary of the dynamic active region representing the crack damage of the concrete structure according to the change condition of the energy fluctuation coefficient in the energy fluctuation coefficient sequence. As a further scheme of the invention, the acoustic emission waveform data segment is specifically a data sequence with a specified length, which is intercepted from a digital waveform data sequence and is located after a trigger time, the multi-parameter discrete evolution feature set comprises an amplitude standard deviation, an energy standard deviation and a duration standard deviation which are calculated for each continuous time window, the non-uniform expansion dominant signal set is specifically a set of acoustic emission waveform data segments associated with a time window with a posterior probability higher than a decision reference probability, the energy fluctuation coefficient sequence comprises a dimensionless energy fluctuation coef