A circuit device for non-destructive and real-time detection of hole defects inside a steel tube concrete column and its detection method

Abstract

The present invention discloses a circuit device and a detection method for non-destructive real-time detection of hole defects inside a steel tube concrete column: comprising a reference signal source, a transmitting circuit electrically connected to the reference signal source, a local oscillator circuit and a multi-channel synchronous sampling analog-to-digital converter, the transmitting circuit electrically connected to a broadband power amplifier, and the broadband power amplifier electrically connected to an electrical small antenna array. The beneficial effect of the present invention is that the pre-buried electrical small antenna array is used, the structure of the original steel tube concrete column of the building is not destroyed, and the hole defects inside the steel tube concrete column can be non-destructively detected in real time without affecting the quality and mechanical properties of the building.

Description

Technical Field

[0001] The invention belongs to the field of nondestructive testing of civil engineering and construction, and particularly relates to a circuit device and a detection method thereof for nondestructive and real-time detection of hole defects inside a steel tube concrete column. Background Art

[0002] Super high-rise buildings are being built in large numbers in my country. Steel tube concrete columns, which have the advantages of high strength, large plastic deformation, good seismic performance and fast construction, are widely used as the main load-bearing system of super high-rise buildings. Since steel tube concrete columns are composed of two completely different materials, concrete is poured into the steel tube during the actual construction process, which cannot guarantee that the inside of the steel tube is completely uniformly filled and free of defects. In order to ensure the mechanical properties of the building structure, destructive detection of steel tube columns cannot be carried out. How to accurately and non-destructively detect the defects of steel tube concrete columns has always been a technical "pain point" that needs to be solved in the construction industry.

[0003] At present, there are certain drawbacks in the defect detection technology of steel tube concrete columns. The main detection methods of steel tube concrete columns at home and abroad are: ultrasonic transmission method, infrared thermal imaging technology, engineering geological radar, etc. The ultrasonic transmission method is greatly affected by the water content of concrete. When the water content in the concrete column is high, the sound wave cannot propagate through the steel tube concrete column. In the actual detection operation of infrared thermal imaging technology, there are problems such as infrared radiation attenuation, interference from the surrounding environment, and uneven heat. The pulse energy of engineering geological detection radar detection technology cannot penetrate metal steel pipes and cannot detect the defects of concrete columns inside steel pipes. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a circuit device and a detection method for non-destructive and real-time detection of hole defects inside a steel tube concrete column.

[0005] The present invention adopts the following technical solution:

[0006] A circuit device for non-destructive and real-time detection of hole defects inside a steel tube concrete column, the improvement of which is that it includes a reference signal source, a transmitting circuit electrically connected to the reference signal source, a local oscillator circuit and a multi-channel synchronous sampling analog-to-digital converter, the transmitting circuit is electrically connected to a broadband power amplifier, the broadband power amplifier is electrically connected to an electrically small antenna array, the number of channels of the electrically small antenna array is more than eight, and each channel is electrically connected to a mixer through a low-noise amplifier, each mixer is electrically connected to a signal output port of the local oscillator circuit and a digitally controlled filter amplifier, each digitally controlled filter amplifier is electrically connected to the same multi-channel synchronous sampling analog-to-digital converter, the multi-channel synchronous sampling analog-to-digital converter is electrically connected to a central processing unit, and the central processing unit is electrically connected to the broadband power amplifier through an auxiliary monitoring module.

[0007] A method for non-destructive real-time detection of hole defects inside a steel tube concrete column uses the above-mentioned circuit device, and its improvement lies in that: under the control of a central processing unit, a transmitting circuit processes a reference signal generated by a reference signal source, outputs a signal of a certain frequency in a time-sharing manner, sends it to a broadband power amplifier for amplification, and then feeds it into an electric small antenna array for transmission; after the electromagnetic wave signal propagates through a concrete medium, the electric small antenna array performs synchronous reception of more than eight channels, and after synchronous reception, it is amplified by a low-noise amplifier group, and the amplified signal and the signal generated by a local oscillator circuit are down-mixed by a mixer group one by one to obtain a multi-channel synchronous low-noise signal. The digital control filter amplifier group filters and amplifies the low-frequency 4KHz signal, and then sends it to the multi-channel synchronous sampling analog-to-digital converter for digital processing to obtain multi-channel synchronous digital signals, which are sent to the central processing unit for solution calculation to obtain the phase and amplitude of each signal in the multi-channel synchronous signal. Finally, the size and position information of the hole defects inside the steel tube concrete column can be obtained through calculation and analysis. During the operation of the system device, the auxiliary monitoring module has been monitoring the working status of the broadband power amplifier, and its working status information is fed back to the central processing unit in real time to ensure that the system device is working in a normal state.

[0008] Furthermore, the frequencies of the time-sharing output include but are not limited to 100 MHz, 200 MHz and 400 MHz.

[0009] Furthermore, the frequencies of the mixer groups correspond one to one: 100 MHz corresponds to 99.996 MHz; 200 MHz corresponds to 199.996 MHz; and 400 MHz corresponds to 399.996 MHz.

[0010] The beneficial effects of the present invention are:

[0011] (1) The use of pre-buried small antenna arrays does not damage the structure of the original steel tube concrete column of the building. It can perform non-destructive real-time detection of hole defects inside the steel tube concrete column without affecting the quality and mechanical properties of the building.

[0012] (2) By using antenna array technology, the absolute phase and amplitude values ​​of each channel signal can be measured simultaneously; an image reflecting the size and location of the hole defect can be obtained, which has the advantages of high resolution and rich information.

[0013] (3) The circuit system device uses high-frequency electromagnetic wave signals with multiple working frequencies, such as 100 MHz, 200 MHz and 400 MHz, to reduce the influence of different resistivities of concrete on its measurement accuracy.

[0014] (4) The circuit system device can be calibrated in the workshop, which improves the measurement accuracy of the instrument.

[0015] (5) The device can effectively monitor the working status of the circuit system in real time to ensure the reliable operation of the instrument. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the circuit device of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] This embodiment is a circuit system device for non-destructive real-time detection of hole defects inside steel tube concrete columns in the field of civil engineering. This circuit device uses a pre-buried small antenna array and a multi-channel receiving circuit. During the construction process of the building project and after delivery to the user, it can obtain the accurate size and precise location information of the hole defects inside the concrete column by non-destructively measuring the response of electromagnetic wave signals of multiple frequencies after propagation through the concrete medium in real time, and guide the later maintenance personnel to deal with them in a targeted manner.

[0019] This embodiment can use a single-channel transmitting circuit and a pre-buried electric small antenna to emit multiple frequency high-frequency electromagnetic wave signals for measuring internal defects of concrete. After the high-frequency electromagnetic wave signal propagates through the concrete medium, it carries information that can characterize the state of the concrete medium. Then, using a multi-channel receiving circuit and a pre-buried electric small antenna array, the electromagnetic wave signal carrying effective information is synchronously received and processed, and the absolute phase and amplitude of multiple propagation paths can be obtained, and then the relative phase and amplitude difference of multiple propagation paths can be deduced. Finally, the relative phase and amplitude difference obtained by calibrating each channel in the air are subtracted, and the size and position information of the hole defect are determined by calculation.

[0020] In order to further improve the system working accuracy, the device can be calibrated in the workshop. In order to improve the system working reliability, the device adds a real-time monitoring feedback circuit.

[0021] This embodiment provides a circuit system device for non-destructive and real-time detection of hole defects inside a steel tube concrete column. The principle is as follows: Figure 1 As shown. It includes: (1) reference signal source (reference source), (2) transmitting circuit, (3) broadband power amplifier, (4) electrically small antenna array, (5) low noise amplifier group, (6) local oscillator circuit, (7) mixer group, (8) digital control filter amplifier group (DCFA), (9) multi-channel synchronous sampling analog-to-digital converter (Mc-ADC), (10) central processing unit (DSP), (11) auxiliary monitoring module (standing wave monitoring, temperature monitoring sensor).

[0022] (1) Reference signal source (reference source): output multiple synchronous oscillation signals: As a reference source for the transmitting circuit. As the reference source of the local oscillator circuit. As the start signal of the multi-channel sampling analog-to-digital converter.

[0023] (2) Transmitter circuit: Use a phase-locked loop to multiply the reference signal source and output multi-frequency (for example: 100 MHz, 200 MHz and 400 MHz) signals in a time-sharing manner.

[0024] (3) Broadband power amplifier: realizes high-power transmission of high-frequency signals with multiple frequencies (for example: 100MHz, 200MHz, 400MHz).

[0025] (4) Electrically small antenna array: Efficiently transmit and receive high-frequency signals.

[0026] (5) Low-noise amplifier group: It is composed of multiple (≥8) low-noise amplifiers, which amplify the weak high-frequency signals received synchronously to improve the measurement sensitivity of the instrument.

[0027] (6) Local oscillator circuit: There are multiple (≥8) signal output ports. The reference signal source is multiplied by a phase-locked loop. Each signal output port outputs a specific frequency (for example: 99.996MHz, 199.996MHz and 399.996MHz) signal synchronously and in a time-sharing manner.

[0028] (7) Mixer group: It is composed of multiple (≥8) mixers, which perform multi-channel synchronous down-conversion of the three received high-frequency signals with the three high-frequency signals generated by the local oscillator circuit to a low frequency of 4KHz.

[0029] (8) Digital control filter amplifier group: It is composed of multiple (≥8) digital control filter amplifiers, which synchronously adjust the gain of multiple receiving channels according to the actual attenuation of high-frequency electromagnetic waves by the concrete medium.

[0030] (9) Multi-channel synchronous sampling analog-to-digital converter: The 4KHz signal (output of the digitally controlled filter amplifier group) obtained by simultaneously down-converting multiple channels is digitized so that it still maintains the synchronous characteristics.

[0031] (10) Central processing unit: Serves as the main controller and signal processing unit of the circuit system, controlling the working status of the instrument; such as: : Control the digital filter amplifiers of multiple receiving channels, adjust the gain of the receiving channels, and expand the dynamic range of receiving weak signals; : Control the multi-channel synchronous sampling analog-to-digital converter to perform synchronous sampling of multi-channel receiving signals; : Perform discrete Fourier transform on the digital signal to solve the absolute phase and amplitude of each receiving channel signal; : Monitor the working status of the broadband power amplifier.

[0032] (11) Auxiliary monitoring module: monitors the working status of the broadband power amplifier and provides real-time feedback to the central processing unit to ensure the normal operation of the system.

[0033] The detection method is as follows:

[0034] The transmitting circuit (2) processes the reference signal generated by the reference signal source (1) under the control of the central processing unit (10), outputs a signal of a certain frequency (for example, 100 MHz, 200 MHz, 400 MHz) in a time-sharing manner, sends it to the broadband power amplifier (3) for amplification, and then feeds it into the electric small antenna array (4) for transmission.

[0035] After the electromagnetic wave signal propagates through the concrete medium, it is synchronously received by the electric small antenna array (4) in 8 channels, and then amplified by the low noise amplifier group (5). The amplified signal and the signal generated by the local oscillator circuit (6) are down-mixed by the mixer group (7) one by one (for example: 100MHz-99.996MHz; 200MHz-199.996MHz; 400MHz-399.996MHz) to obtain multiple synchronous low-frequency 4KHz signals. After the digital control filter amplifier group (8) performs filtering and amplification processing on the low-frequency 4KHz signal, it is sent to the multi-channel synchronous sampling analog-to-digital converter (9) for digital processing to obtain multiple synchronous digital signals, which are sent to the central processing unit (10) for solution operation to obtain the phase and amplitude of each signal in the multiple synchronous signals, and finally the size and position information of the hole defects inside the steel tube concrete column can be obtained through calculation and analysis.

[0036] During the operation of the system device, the auxiliary monitoring module (11) continuously monitors the operating state of the broadband power amplifier and feeds back its operating state information to the central processing unit (10) in real time, thereby ensuring that the system device operates in a normal state.

[0037] The calibration method is as follows:

[0038] The circuit device is placed in the air in the workshop, and the relative phase and amplitude difference of each receiving channel can be calculated using the absolute phase and amplitude of each channel obtained by the central processing unit.

[0039] This embodiment provides a design method and implementation method of a circuit system device for non-destructive real-time detection of hole defects inside steel tube concrete columns. Through the circuit system device of this embodiment, during the construction process and after delivery to the user, without destroying the building structure such as the steel tube column, multiple working frequency technologies can be used to reduce the impact of different resistivities of concrete on measurement accuracy; pre-buried small antenna arrays and multi-channel receiving technology can be used to non-destructively measure the absolute phase and amplitude values ​​of multiple propagation paths in real time, and the size and position of the hole defects can be accurately located, which is also convenient for future real-time monitoring and maintenance of buildings.

Claims

1. A method for non-destructive real-time detection of hole defects inside a steel tube concrete column, using a circuit device for non-destructive real-time detection of hole defects inside a steel tube concrete column, comprising a reference signal source, a transmitting circuit electrically connected to the reference signal source, a local oscillator circuit and a multi-channel synchronous sampling analog-to-digital converter, the transmitting circuit is electrically connected to a broadband power amplifier, the broadband power amplifier is electrically connected to a pre-buried electrical small antenna array, the number of channels of the electrical small antenna array is more than eight, and each channel is electrically connected to a mixer through a low noise amplifier, each mixer is electrically connected to a signal output port of the local oscillator circuit and a digitally controlled filter amplifier, each digitally controlled filter amplifier is electrically connected to the same multi-channel synchronous sampling analog-to-digital converter, the multi-channel synchronous sampling analog-to-digital converter is electrically connected to a central processing unit, and the central processing unit is electrically connected to the broadband power amplifier through an auxiliary monitoring module, characterized in that: Under the control of the central processing unit, the transmitting circuit processes the reference signal generated by the reference signal source, outputs a signal of a certain frequency in a time-sharing manner, sends it to the broadband power amplifier for amplification, and then feeds it into the small antenna array for transmission; After the electromagnetic wave signal propagates through the concrete medium, it is synchronously received by more than eight channels by the electric small antenna array, and then amplified by the low-noise amplifier group. The amplified signal and the signal generated by the local oscillator circuit are down-mixed one by one by the mixer group to obtain multiple synchronous low-frequency 4KHz signals. After the digital control filter amplifier group filters and amplifies the low-frequency 4KHz signal, it is sent to the multi-channel synchronous sampling analog-to-digital converter for digital processing to obtain multiple synchronous digital signals, which are sent to the central processing unit for solution calculation to obtain the phase and amplitude of each signal in the multiple synchronous signals. Finally, the size and position information of the hole defects inside the steel tube concrete column can be obtained through calculation and analysis. During the operation of the system device, the auxiliary monitoring module has been monitoring the working status of the broadband power amplifier, and its working status information is fed back to the central processing unit in real time to ensure that the system device operates in a normal state.

2. The method for non-destructive and real-time detection of hole defects inside a concrete-filled steel tube column according to claim 1 is characterized in that: The frequencies of the time-sharing output include but are not limited to 100 MHz, 200 MHz and 400 MHz.

3. The method for non-destructive and real-time detection of hole defects inside a concrete-filled steel tube column according to claim 2 is characterized in that: The frequencies of the mixer groups correspond to each other as follows: 100 MHz corresponds to 99.996 MHz; 200 MHz corresponds to 199.996 MHz; and 400 MHz corresponds to 399.996 MHz.

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