A reinforced concrete damage assessment method and system based on acoustic emission total fault area

Abstract

The invention discloses a reinforced concrete damage assessment method based on acoustic emission total fault area. The total fault area theory is used to fully consider the number of events and energy parameters, calculate the total fault area of ​​acoustic emission, accumulate the total fault area of ​​acoustic emission to obtain the total fault area growth rate, and in the critical period when the reinforced concrete is broken, the sudden increase of the accumulated total fault area growth rate is used as a feature to judge the internal damage state of the reinforced concrete beam specimen, propose a reasonable acoustic emission signal monitoring method for damage identification and early warning using acoustic emission technology, and provide a reasonable basis for the judgment of reinforced concrete damage in actual engineering; the invention correspondingly provides a reinforced concrete damage assessment system based on acoustic emission total fault area.

Description

Technical Field

[0001] The invention relates to the field of beam specimen damage detection, in particular to a reinforced concrete damage assessment method based on acoustic emission fault total area. Background Art

[0002] Reinforced concrete structures are widely used in various construction fields, and their safety and stability are increasingly receiving attention. As a non-destructive testing method, acoustic emission technology can store the acoustic emission signals of the cracking and destruction of components in real time by receiving elastic waves generated by the changes in internal damage of the structure, and evaluate the degree of structural damage by analyzing the signals. However, there is still a lack of effective and accurate means to use the characteristics of the signals to evaluate the degree of damage of reinforced concrete components.

[0003] There are existing methods for concrete damage analysis based on acoustic emission parameters, such as CN110702517A, which analyzes concrete damage based on the proportion of acoustic emission parameter stage accumulation, CN111812211B, which uses acoustic emission energy parameters as the intensity characteristics of cracks and the corresponding RA value AF value to classify crack types; CNIO7345875A, which evaluates the stiffness of reinforced concrete bending members based on acoustic emission ring counts. The above methods basically process and analyze the changes of each single acoustic emission parameter, and have no clear physical meaning related to the rupture of beam specimens. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a reinforced concrete damage assessment method based on the total area of ​​acoustic emission faults, taking into account the number of events and energy parameters, while calculating the total area of ​​faults, accumulating the growth rate of the total area of ​​faults, and thus judging the internal damage state of reinforced concrete beam specimens. The present invention also provides a reinforced concrete damage assessment system based on the total area of ​​acoustic emission faults.

[0005] Technical solution: The present invention provides a reinforced concrete damage assessment method based on acoustic emission fault total area, comprising the following steps:

[0006] 1) Collect the acoustic emission signals of the reinforced concrete beam specimen under four-point bending graded loading until the reinforced concrete beam is broken, and summarize the acoustic emission signals collected during the process to obtain the loading curve and time history diagram;

[0007] 2) Combined with the fragmentation process of reinforced concrete beam specimens, the absolute energy of acoustic emission is calculated, and the acoustic emission energy level is calculated at the same time;

[0008] 3) According to the total fault area theory, calculate the total acoustic emission fault area A(t);

[0009] 4) Accumulate the calculated total fault area A(t) values ​​to obtain a history diagram of the cumulative total fault area and time;

[0010] 5) Select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; use the sudden increase in the cumulative total fault area growth rate as a feature to determine the internal damage state of the reinforced concrete beam specimen.

[0011] Further, step 2) comprises the following steps:

[0012] 2.1) Obtain the absolute energy of acoustic emission using the following formula:

[0013]

[0014] Where E is the absolute energy, unit is aJ, t1 to t2 is the duration of the acoustic emission, V rms is the effective voltage of the acoustic emission signal, and R is the impedance;

[0015] 2.2) According to the Gutenberg formula, in seismology, energy and magnitude have the following relationship:

[0016] log 10 E=a+bM

[0017] Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as:

[0018] K = log 10 E

[0019] The acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained using the above formula.

[0020] Further, in step 3), a total acoustic emission fault area A(t) between the earthquake frequency and the earthquake energy is defined, and the calculation formula of the total acoustic emission fault area A(t) is as follows;

[0021]

[0022] Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, then A(t) represents the sum of the number of events of all acoustic emission energy levels, when L = 10, then A(t) represents the total energy of all events;

[0023] In the total fault area theory, it is assumed that before the reinforced concrete beam specimen breaks, the reinforced concrete beam specimen reaches the critical strain state before breaking, then:

[0024]

[0025] Pick

[0026]

[0027] Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

[0028] The present invention also provides a reinforced concrete damage assessment system based on the total area of ​​acoustic emission faults, which comprises a collection module, an acoustic emission energy level module, an acoustic emission total area fault module, an accumulation module, and a judgment module;

[0029] The acquisition module is used to collect the acoustic emission signals of the reinforced concrete beam specimen under the four-point bending graded loading until the reinforced concrete beam is broken, and the acoustic emission signals collected in the process are summarized to obtain the loading curve and time history diagram;

[0030] The acoustic emission energy level module is used to calculate the absolute energy of acoustic emission and the acoustic emission energy level in combination with the fragmentation process of reinforced concrete beam specimens;

[0031] The acoustic emission fault total area module is used to calculate the acoustic emission fault total area A(t) according to the fault total area theory;

[0032] The accumulation module is used to accumulate the calculated total fault area A(t) value to obtain a history diagram of the accumulated total fault area and time;

[0033] The judgment module is used to select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; the sudden increase in the cumulative total fault area growth rate is used as a feature to judge the internal damage state of the reinforced concrete beam specimen.

[0034] Further, the acoustic emission energy level module includes an absolute energy unit and an acoustic emission energy level unit;

[0035] The absolute energy unit is used to obtain the absolute energy of acoustic emission, which is obtained by the following formula:

[0036]

[0037] Where E is the absolute energy, unit is aJ, t1 to t2 is the duration of the acoustic emission, V rms is the effective voltage of the acoustic emission signal, and R is the impedance;

[0038] The acoustic emission energy level unit is used to calculate according to the Gutenberg formula. In seismology, the energy and magnitude have the following relationship:

[0039] log 10 E=a+bM

[0040] Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as:

[0041] K = log 10 E

[0042] The acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained using the above formula.

[0043] Furthermore, in the acoustic emission fault total area module, a total acoustic emission fault area A(t) between the earthquake frequency and the earthquake energy is defined, and the calculation formula of the acoustic emission fault total area A(t) is as follows;

[0044]

[0045] Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, then A(t) represents the sum of the number of events of all acoustic emission energy levels, when L = 10, then A(t) represents the total energy of all events;

[0046] In the total fault area theory, it is assumed that before the reinforced concrete beam specimen breaks, the reinforced concrete beam specimen reaches the critical strain state before breaking, then:

[0047]

[0048] Pick

[0049]

[0050] Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

[0051] Beneficial effect: Compared with the prior art, the present invention has the remarkable feature of fully considering the number of events and energy parameters through the total fault area theory, calculating the total acoustic emission fault area, accumulating the total acoustic emission fault area to obtain the total fault area growth rate, and judging the internal damage state of the reinforced concrete beam specimen by taking the sudden increase of the cumulative total fault area growth rate as a feature during the critical period when reinforced concrete breaks, proposing a reasonable acoustic emission signal monitoring method for damage identification and early warning using acoustic emission technology, and providing a reasonable basis for the judgment of reinforced concrete damage in actual engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a schematic diagram of experimental loading in the present invention;

[0053] Figure 2It is the size and reinforcement diagram of the reinforced concrete beam specimen in the present invention;

[0054] Figure 3 It is a history diagram of loading curve and time in the present invention;

[0055] Figure 4 It is a history diagram of the cumulative total fault area A(t) value and time in the present invention;

[0056] Figure 5 It is a history diagram of the acoustic emission amplitude and the cumulative total fault area A(t) value and time in the present invention;

[0057] Figure 6 It is a history diagram of the acoustic emission energy and the cumulative total fault area A(t) value and time in the present invention;

[0058] Figure 7 It is a history diagram of the acoustic emission ringing count and the cumulative total fault area A(t) value and time in the present invention. DETAILED DESCRIPTION

[0059] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] Example 1

[0061] The present invention provides a reinforced concrete damage assessment method based on acoustic emission fault total area, comprising the following steps:

[0062] 1) Collect the acoustic emission signals of reinforced concrete beam specimens under four-point bending graded loading until the reinforced concrete beam breaks, and obtain the loading curve and time history diagram.

[0063] See also Figure 1 As shown, an acoustic emission sensor is set at both ends of one side of the reinforced concrete beam specimen, and loading is carried out using a four-point bending graded loading method. Each level of loading requires a period of time to ensure that the cracks are fully developed, and loading is performed until the reinforced concrete beam specimen is broken.

[0064] The concrete strength used in the reinforced concrete beam specimens in the test is C20. The test uses a beam of 100mm×150mm×1200mm and is equipped with necessary steel bars. The reinforcement diagram and main dimensions are as follows: Figure 2 As shown in the figure, the measured compressive strength after 28 days is 22MPa. Four-point bending loading is used to make the middle part of the beam in a pure bending state, and graded loading is used to release the deformation of the concrete in time. The loading system consists of three parts: a self-balancing reaction frame, a manual hydraulic jack and a pressure sensor. The reaction frame is used for vertical loading. The load capacity of each level is determined to be 5kN according to the estimated maximum load. Acoustic emission sensors are used for data collection. The layout diagram is shown in the figure. Figure 1 As shown in the figure, the load applied by the testing machine to the beam changes with time as shown in the figure Figure 3 shown.

[0065] 2) Combined with the fragmentation process of reinforced concrete beam specimens, the absolute energy of acoustic emission is calculated, and the acoustic emission energy level is also calculated.

[0066] 2.1) Combining the damage development characteristics of the reinforced concrete beam specimen fragmentation process and the characteristics of the acoustic emission energy parameters, the absolute energy of the acoustic emission is first obtained. Usually, the acoustic emission system is connected to an amplifier after the sensor. The absolute energy is required to be reduced to this gain. Only the voltage at the output end of the sensor is calculated. The square of the voltage at the output end of the sensor is integrated over time. The integral is divided by the impedance of 10kΩ to obtain the absolute energy. The absolute energy is not affected by the pre-gain and can be intuitively compared with the energy in physics:

[0067]

[0068] Where E is the absolute energy, unit is aJ (1aJ = 10 -18 J), t1 to t2 is the duration of acoustic emission, V rms is the effective signal voltage, and R is the impedance of 10kΩ.

[0069] 2.2) According to the Gutenberg formula, in seismology, energy and magnitude have the following relationship:

[0070] log 10 E=a+bM

[0071] Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as:

[0072] K = log 10 E

[0073] Where E is the absolute energy, unit is aJ (1aJ = 10 -18 J), the acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained by the above formula.

[0074] 3) According to the total fault area theory, calculate the total acoustic emission fault area A(t);

[0075] Define a total acoustic emission fault area A(t) between earthquake frequency and earthquake energy. In the acoustic emission system, when evaluating activity by signal frequency and energy, the number of low-energy events exceeds the number of high-energy events. The number of events is determined by low-energy events, and the total energy is determined by the number of high-energy events, which are in the minority. To overcome this contradiction, the total acoustic emission fault area A(t) takes into account both the number of events and the energy. The above is the total fault area theory.

[0076] The acoustic emission signals are grouped and 50 points are taken as a group to calculate the total fault area of ​​each group of signals. This also takes into account the convenience of real-time monitoring and calculation in actual engineering applications. Combined with the total fault area theory, the calculation formula of the total fault area A(t) of acoustic emission is as follows;

[0077]

[0078] Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, A(t) represents the sum of the number of events of all acoustic emission energy levels, and when L = 10, A(t) represents the total energy of all events.

[0079] In the total fault area theory, before the reinforced concrete beam specimen is broken, the reinforced concrete beam specimen reaches the critical strain state before the breakage, and the critical strain state is a constant value, so the energy is proportional to the volume of the breakage source, that is, proportional to the 3 / 2 power of the breakage source fault area, then:

[0080]

[0081] At this time, A(t) is proportional to the total area of ​​the fault.

[0082]

[0083] Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

[0084] 4) Please refer to Figure 4 As shown, the calculated total fault area A(t) values ​​are accumulated to obtain a history diagram of the cumulative total fault area and time.

[0085] 5) Select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; use the sudden increase in the cumulative total fault area growth rate as a feature to determine the internal damage state of the reinforced concrete beam specimen.

[0086] Select the cumulative total fault area and time history diagram obtained in step 4) to obtain the point where the cumulative total fault area growth rate suddenly increases, such as Figure 5 , Figure 6 and Figure 7 Points A, B, C, D, and E in the figure can be used as characteristics of damage to the reinforced concrete beam specimens.

[0087] After the points where the cumulative total fault area A(t) value begins to increase suddenly, the number of acoustic emission events increases, the high amplitude points become more dense, and the acoustic emission energy and ringing counts also reach peak values ​​for a period of time.

[0088] At around 182s, after point A in the figure, the growth rate of the cumulative total fault area A(t) value suddenly increased to 88.75 per second. When the load was about 10.4kN, the first fine crack appeared at the bottom of the mid-span of the reinforced concrete beam specimen. From 277s to 368s, after point B in the figure, the growth rate of the cumulative A(t) value suddenly increased to about 200 per second. During the process of increasing the load from 20kN to 30kN, the original crack expanded upward and increased in width. At the same time, multiple cracks germinated. When the test was carried out to around 648s, point D in the figure Afterwards, the growth rate of the cumulative A(t) value suddenly increased to about 87 per second, and multiple fine cracks gradually penetrated and rapidly expanded toward the top of the mid-span. From 947s to 1078s, after point E in the figure, the growth rate of the cumulative A(t) value suddenly increased to about 177.5 per second. When loaded to 65kN and at 1078s, the mid-span crack expanded rapidly and penetrated. A wider crack extended from the right side of the bottom of the mid-span of the reinforced concrete beam specimen to the top of the mid-span of the reinforced concrete beam specimen. Cracking sounds could be heard during the test, and the reinforced concrete beam specimen lost its bearing capacity.

[0089] The experiment shows that during the critical period when reinforced concrete beam specimens break, when multiple acoustic emission events, high amplitude, high energy, and high ringing counts occur, the cumulative total fault area A(t) value growth rate will also suddenly increase. The point of each sudden increase in the cumulative total fault area A(t) value growth rate is used as a feature to determine the internal damage state of the reinforced concrete beam component.

[0090] Example 2

[0091] Corresponding to Example 1, this embodiment provides a reinforced concrete damage assessment system based on the total area of ​​acoustic emission faults, comprising a collection module, an acoustic emission energy level module, an acoustic emission total area fault module, an accumulation module, and a judgment module;

[0092] The acquisition module is used to collect the acoustic emission signals of the reinforced concrete beam specimen under four-point bending graded loading until the reinforced concrete beam breaks, and obtain the loading curve and time history diagram.

[0093] See also Figure 1As shown, an acoustic emission sensor is set at both ends of one side of the reinforced concrete beam specimen, and loading is carried out using a four-point bending graded loading method. Each level of loading requires a period of time to ensure that the cracks are fully developed, and loading is performed until the reinforced concrete beam specimen is broken.

[0094] The concrete strength used in the reinforced concrete beam specimens in the test is C20. The test uses a beam of 100mm×150mm×1200mm and is equipped with necessary steel bars. The reinforcement diagram and main dimensions are as follows: Figure 2 As shown in the figure, the measured compressive strength after 28 days is 22MPa. Four-point bending loading is used to make the middle part of the beam in a pure bending state, and graded loading is used to release the deformation of the concrete in time. The loading system consists of three parts: a self-balancing reaction frame, a manual hydraulic jack and a pressure sensor. The reaction frame is used for vertical loading. The load capacity of each level is determined to be 5kN according to the estimated maximum load. AE sensors are used for data collection. The layout diagram is shown in the figure. Figure 1 As shown in the figure, the load applied by the testing machine to the beam changes with time as shown in the figure Figure 3 shown.

[0095] The acoustic emission energy level module is used to calculate the absolute energy of acoustic emission and the acoustic emission energy level in combination with the fragmentation process of reinforced concrete beam specimens.

[0096] The acoustic emission energy level module includes absolute energy unit and acoustic emission energy level unit;

[0097] In the absolute energy unit, the absolute energy of acoustic emission is first obtained by combining the damage development characteristics of the reinforced concrete beam specimen fragmentation process and the characteristics of the acoustic emission energy parameters. Usually, the acoustic emission system is connected to an amplifier after the sensor. The absolute energy is required to be reduced to this gain. Only the voltage at the output end of the sensor is calculated. The square of the voltage at the output end of the sensor is integrated over time. The integral is divided by the impedance of 10kΩ to obtain the absolute energy. The absolute energy is not affected by the pre-gain and can be intuitively compared with the energy in physics:

[0098]

[0099] Where E is the absolute energy, unit is aJ (1aJ = 10 -18 J), t1 to t2 is the duration of acoustic emission, V rms is the effective signal voltage, and R is the impedance of 10kΩ.

[0100] In the acoustic emission energy level unit, the calculation is performed according to the Gutenberg formula. In seismology, the energy and magnitude have the following relationship:

[0101] log 10 E=a+bM

[0102] Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as:

[0103] K = log 10 E

[0104] Where E is the absolute energy, unit is aJ (1aJ = 10 -18 J), the acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained by the above formula.

[0105] The acoustic emission fault total area module is used to calculate the acoustic emission fault total area A(t) according to the fault total area theory.

[0106] Define a total acoustic emission fault area A(t) between earthquake frequency and earthquake energy. In the acoustic emission system, when evaluating activity by signal frequency and energy, the number of low-energy events exceeds the number of high-energy events. The number of events is determined by low-energy events, and the total energy is determined by the number of high-energy events, which are in the minority. To overcome this contradiction, the total acoustic emission fault area A(t) takes into account both the number of events and the energy. The above is the total fault area theory.

[0107] The acoustic emission signals are grouped and 50 points are taken as a group to calculate the total fault area of ​​each group of signals. This also takes into account the convenience of real-time monitoring and calculation in actual engineering applications. Combined with the total fault area theory, the calculation formula of the total fault area A(t) of acoustic emission is as follows;

[0108]

[0109] Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, A(t) represents the sum of the number of events of all acoustic emission energy levels, and when L = 10, A(t) represents the total energy of all events.

[0110] In the total fault area theory, before the reinforced concrete beam specimen is broken, the reinforced concrete beam specimen reaches the critical strain state before the breakage, and the critical strain state is a constant value, so the energy is proportional to the volume of the breakage source, that is, proportional to the 3 / 2 power of the breakage source fault area, then:

[0111]

[0112] At this time, A(t) is proportional to the total area of ​​the fault.

[0113]

[0114] Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

[0115] See also Figure 4 As shown, the accumulation module is used to accumulate the calculated total fault area A(t) value to obtain a history diagram of the accumulated total fault area and time.

[0116] The judgment module is used to select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; the sudden increase in the cumulative total fault area growth rate is used as a feature to judge the internal damage state of the reinforced concrete beam specimen.

[0117] Select the cumulative total fault area and time history diagram obtained in the accumulation module to obtain the point where the cumulative total fault area growth rate suddenly increases, such as Figure 4 , Figure 5 and Figure 6 Points A, B, C, D, and E in the figure can be used as characteristics of damage to the reinforced concrete beam specimens.

[0118] After the points where the cumulative total fault area A(t) value begins to increase suddenly, the number of acoustic emission events increases, the high amplitude points become more dense, and the acoustic emission energy and ringing counts also reach peak values ​​for a period of time.

[0119] At around 182s, after point A in the figure, the growth rate of the cumulative total fault area A(t) value suddenly increased to 88.75 per second. When the load was about 10.4kN, the first fine crack appeared at the bottom of the mid-span of the reinforced concrete beam specimen. From 277s to 368s, after point B in the figure, the growth rate of the cumulative A(t) value suddenly increased to about 200 per second. During the process of increasing the load from 20kN to 30kN, the original crack expanded upward and increased in width. At the same time, multiple cracks germinated. When the test was carried out to around 648s, point D in the figure Afterwards, the growth rate of the cumulative A(t) value suddenly increased to about 87 per second, and multiple fine cracks gradually penetrated and rapidly expanded toward the top of the mid-span. From 947s to 1078s, after point E in the figure, the growth rate of the cumulative A(t) value suddenly increased to about 177.5 per second. When loaded to 65kN and at 1078s, the mid-span crack expanded rapidly and penetrated. A wider crack extended from the right side of the bottom of the mid-span of the reinforced concrete beam specimen to the top of the mid-span of the reinforced concrete beam specimen. Cracking sounds could be heard during the test, and the reinforced concrete beam specimen lost its bearing capacity.

[0120] The experiment shows that during the critical period when reinforced concrete beam specimens break, when multiple acoustic emission events, high amplitude, high energy, and high ringing counts occur, the cumulative total fault area A(t) value growth rate will also suddenly increase. The point of each sudden increase in the cumulative total fault area A(t) value growth rate is used as a feature to determine the internal damage state of the reinforced concrete beam component.

Claims

1. A reinforced concrete damage assessment method based on acoustic emission fault total area, characterized in that: The following steps are involved: 1) Collect the acoustic emission signals of the reinforced concrete beam specimen under four-point bending graded loading until the reinforced concrete beam is broken, and summarize the acoustic emission signals collected during the process to obtain the loading curve and time history diagram; 2) Combined with the fragmentation process of reinforced concrete beam specimens, the absolute energy of acoustic emission is calculated, and the acoustic emission energy level is calculated at the same time; 3) According to the total fault area theory, calculate the total acoustic emission fault area A(t); 4) Accumulate the calculated total fault area A(t) values ​​to obtain a history diagram of the cumulative total fault area and time; 5) Select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; The sudden increase of the cumulative total fault area growth rate is used as a feature to determine the internal damage state of the reinforced concrete beam specimen; In step 3), a total acoustic emission fault area A(t) between the earthquake frequency and the earthquake energy is defined, and the calculation formula of the total acoustic emission fault area A(t) is as follows; Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, then A(t) represents the sum of the number of events of all acoustic emission energy levels, when L = 10, then A(t) represents the total energy of all events; In the total fault area theory, it is assumed that before the reinforced concrete beam specimen breaks, the reinforced concrete beam specimen reaches the critical strain state before breaking, then: Pick Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

2. The reinforced concrete damage assessment method based on acoustic emission fault total area according to claim 1 is characterized in that: Step 2) includes the following steps: 2.1) Obtain the absolute energy of acoustic emission using the following formula: Where E is the absolute energy, unit is aJ, t1 to t2 is the duration of the acoustic emission, V rms is the effective voltage of the acoustic emission signal, and R is the impedance; 2.2) According to the Gutenberg formula, in seismology, energy and magnitude have the following relationship: log 10 E=a+bM Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as: K=log 10 AND The acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained using the above formula.

3. A reinforced concrete damage assessment system based on acoustic emission fault total area, characterized in that: It includes acquisition module, acoustic emission energy level module, acoustic emission fault total area module, accumulation module and judgment module; The acquisition module is used to collect the acoustic emission signals of the reinforced concrete beam specimen under the four-point bending graded loading until the reinforced concrete beam is broken, and the acoustic emission signals collected in the process are summarized to obtain the loading curve and time history diagram; The acoustic emission energy level module is used to calculate the absolute energy of acoustic emission and the acoustic emission energy level in combination with the fragmentation process of reinforced concrete beam specimens; The acoustic emission fault total area module is used to calculate the acoustic emission fault total area A(t) according to the fault total area theory; The accumulation module is used to accumulate the calculated total fault area A(t) value to obtain a history diagram of the accumulated total fault area and time; The judgment module is used to select the history diagram of the cumulative total fault area and time to obtain the cumulative total fault area growth rate; The sudden increase of the cumulative total fault area growth rate is used as a feature to determine the internal damage state of the reinforced concrete beam specimen; In the acoustic emission fault total area module, a total acoustic emission fault area A(t) between earthquake frequency and earthquake energy is defined. The calculation formula of the total acoustic emission fault area A(t) is as follows; Where K is the acoustic emission energy level, N(K) is the number of times the energy level is equal to K, when L = 1, then A(t) represents the sum of the number of events of all acoustic emission energy levels, when L = 10, then A(t) represents the total energy of all events; In the total fault area theory, it is assumed that before the reinforced concrete beam specimen breaks, the reinforced concrete beam specimen reaches the critical strain state before breaking, then: Pick Among them, K0 is the lower limit of the acoustic emission energy level. Combined with the acoustic emission energy level K, the total area of ​​the acoustic emission fault during the fragmentation of the reinforced concrete beam specimen is obtained by the above formula.

4. The reinforced concrete damage assessment system based on acoustic emission total fault area according to claim 3 is characterized in that: The acoustic emission energy level module includes absolute energy unit and acoustic emission energy level unit; The absolute energy unit is used to obtain the absolute energy of acoustic emission, which is obtained by the following formula: Where E is the absolute energy, unit is aJ, t1 to t2 is the duration of the acoustic emission, V rms is the effective voltage of the acoustic emission signal, and R is the impedance; The acoustic emission energy level unit is used to calculate according to the Gutenberg formula. In seismology, the energy and magnitude have the following relationship: log 10 E=a+bM Where M is the Richter magnitude, a and b are constants, obtained by linear fitting. A magnitude difference of 1 level results in a release energy difference of 10 b times, based on the Gutenberg formula, the Richter magnitude M is replaced by the energy level, and the acoustic emission energy level K is defined as: K=log 10 AND The acoustic emission energy level during the fragmentation of reinforced concrete beam specimens was obtained using the above formula.

5. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to claim 1 or claim 2 are implemented.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to claim 1 or claim 2 are implemented.

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