Dual-mode electrical resistivity or impedance tomography measurement device for soil seepage flow channels
By integrating excitation signal conditioning, data acquisition, and channel switching modules, a dual-modal tomographic measurement device for soil seepage channel resistivity or impedance has been developed, solving the problems of high equipment cost and low detection accuracy in traditional methods and achieving efficient and low-cost detection of soil seepage channels.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-10
- Publication Date
- 2026-03-31
AI Technical Summary
Traditional resistivity tomography and electrical impedance tomography measurements require two separate detection devices, resulting in high equipment costs, significant signal interference, high failure rates, and difficulty in simultaneously achieving high-resolution detection of soil seepage channels.
Design a dual-modal tomographic measurement device for soil seepage channel resistivity or electrical impedance, integrating an excitation signal conditioning module, a data acquisition module, a channel switching module, and a sensing electrode module to achieve joint detection of ERT and EIT, and control channel switching and data processing through computer control.
It improves data acquisition efficiency, reduces hardware and labor costs, achieves high-resolution detection of soil seepage channels, enhances detection accuracy and technical practicality, and is suitable for soil seepage channel detection in complex environments.
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Figure CN119861113B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of geophysical exploration and geotechnical engineering monitoring technology, specifically to a dual-mode tomographic imaging measurement device for soil seepage channel resistivity or impedance. Background Technology
[0002] In the fields of geophysical exploration and geotechnical engineering monitoring, the accurate characterization and identification of soil seepage channels is crucial for ensuring the safety and stability of earth-rock infrastructure structures such as dams. Earth-rock dams, as important barriers for the optimal utilization of water resources and the prevention of floods and droughts, are widely used globally. However, due to various factors, such as soil cracking due to wet-dry cycles, habitats for animals that damage the dam, and hydraulic erosion and seepage damage, seepage channels can form. These seepage channels are the primary cause of dam failure and even dam collapse.
[0003] Electrical tomography (EIT) technology, due to its advantages such as being radiation-free, having a fast response speed, and being inexpensive, has been widely used in soil aquifer characterization and structural defect monitoring. Among these, resistivity tomography (ERT) and electrical impedance tomography (EIT) are two widely used methods in soil and rock structure inspection. Resistivity tomography uses a direct current (DC) signal as the excitation signal, and the parameter obtained is resistivity; while electrical impedance tomography uses an alternating current (AC) signal as the excitation signal, and the parameter obtained is impedance. Although these two techniques each have their advantages, their sensitivity to identifying anomalies in soil structures differs because DC resistivity and impedance have different sensitivities to parameters such as soil moisture content. Furthermore, due to the influence of observation modes and inversion models, resistivity tomography often struggles to characterize anomalies in boundary regions, while electrical impedance tomography has higher resolution for boundary region anomalies but relatively weaker ability to characterize the internal structure.
[0004] To improve the accuracy of detecting and identifying soil seepage channels, combining resistivity tomography with electrical impedance tomography is an effective approach. However, traditional resistivity tomography and electrical impedance tomography measurements require two independent detection devices to collect data, and the sensing electrodes need to be connected to their respective acquisition devices. This significantly increases the complexity of combining the two methods, raises equipment costs, and may lead to signal interference and a higher probability of failure in field applications.
[0005] Therefore, based on this, we have studied and improved the existing technology and proposed a dual-modal tomographic imaging measurement device for soil seepage channel resistivity or impedance. Summary of the Invention
[0006] This invention provides a resistivity or impedance dual-mode tomography measurement device to achieve rapid and high-resolution detection and characterization of soil seepage channels by combining ERT and EIT.
[0007] The technical solution adopted in this invention is: a dual-modal tomographic imaging measurement device for resistivity or impedance of soil seepage channels, characterized in that: it includes an excitation signal adjustment module, a data acquisition module, a channel switching module, a sensing electrode module, and a computer;
[0008] The excitation signal conditioning module consists of a signal generation module and an isolation switch QS;
[0009] The data acquisition module consists of a power analysis module, a multi-channel synchronous acquisition module, a signal conditioning module, and a lock-in amplifier module.
[0010] The channel switching module consists of relay switch module A and relay switch module B. Each relay has multiple channels, and each channel includes three general-purpose ports: normally open (NO), common (COM), and normally closed (NC). The normally closed (NCA) terminals of relay switch module A are connected to the phase-locked amplifier module via wires. All normally open (NOA) terminals of relay switch module A are connected in series via wires and connected to the positive terminal of the power analysis module. The common (COMA) terminal of relay switch module A is connected to the normally closed (NCB) terminal of relay switch module B via wires. All normally open (NOB) terminals of relay switch module B are connected in series via wires and connected to the negative terminal of the power analysis module. The common (COMB) terminal of relay switch module B is connected to the corresponding channel on the hub.
[0011] The sensing electrode module consists of sensing electrodes and a hub; the sensing electrodes are made of stainless steel or graphite inert electrode material and are connected to the corresponding channel of the hub through wires; finally, the GND of the multi-channel synchronous acquisition module is connected to the negative terminal of the power analysis module.
[0012] The signal generation module, data acquisition module, and channel switching module are connected to the computer via a data transmission line, and channel switching control and data acquisition processing are realized through the host computer software on the computer.
[0013] As a further aspect of the present invention: the signal generation module is used to provide the periodic excitation electrical signal required in resistivity or impedance tomography detection, and the isolating switch QS is used to be adjusted to a closed state to provide a zero potential boundary around the area to be measured when resistivity tomography detection is carried out.
[0014] As a further aspect of the present invention: the power analysis module is connected to the signal generation module via wires and data transmission lines, and is used to acquire excitation voltage signals and main circuit current signals; the multi-channel synchronous acquisition module is used to acquire voltage signals of each channel corresponding to the sensing electrode; the signal conditioning module is used to amplify and preprocess the raw voltage signals of each channel; the lock-in amplifier module is mainly used to enhance the target signal and suppress noise, thereby improving the quality of the voltage signal; the multi-channel synchronous acquisition module is connected to the signal conditioning module via data transmission lines, and the signal conditioning module is connected to the lock-in amplifier module via data transmission lines.
[0015] As a further aspect of the present invention, a measurement step is also included:
[0016] S1. Measurement preparation; Connect each module and the deployed sensing electrodes through data transmission lines and wires; Test the communication status between the computer and each module; Set the excitation signal parameters and data acquisition frequency through the computer; Import the pole running file of the control channel to switch modules.
[0017] S2, Resistivity Tomography Test; Close the isolating switch QS, connect the negative terminal of the power analysis module to the conductive copper foil around the test area via a wire; set the output voltage of the signal generation module to a rectangular pulse signal; switch all switches of relay switch module B to normally closed contacts (NCB); after starting to execute the polarization test file, control the switch on the Y1 channel of relay switch module A to normally open contact (NOA1) and maintain it for 5 seconds, then control the switch on the Y1 channel of relay switch module A to normally closed contact (NCA1) and maintain it for 2 seconds; then control the switch on the Y2 channel of relay switch module A to normally open contact (NOA2) and maintain it for 5 seconds, then control the switch on the Y2 channel of relay switch module A to normally closed contact (NCA2) and maintain it for 2 seconds; repeat the above operation until the above switch switching action traverses all channels of relay switch module A; extract the peak voltage on the corresponding channel of sensing electrodes E1 to E25 obtained by the computer, and the peak current corresponding to each switch being switched to the normally open contact;
[0018] S3, Electrical impedance tomography test; disconnect the isolating switch QS, set the output voltage of the signal generation module to a sinusoidal pulse signal, and reset the switches of relay switch module A and relay switch module B to normally closed (NC) contacts; after starting to execute the polarization test file, control the switch on the X2 channel of relay switch module B to the normally open contact (NOB2) and maintain it for 10 seconds, then control the switch on the Y1 channel of relay switch module A to the normally open contact (NOA1) and maintain it for 5 seconds, then control the switch on the Y1 channel of relay switch module A to the normally closed contact (NCA1) and maintain it for 5 seconds, and then control the switch on the X2 channel of relay switch module B to the normally closed contact (NCB2);
[0019] Then, the switch on channel X3 of relay switch module B is switched to the normally open contact (NOB3) and held for 10 seconds. Then, the switch on channel Y2 of relay switch module A is switched to the normally open contact (NOA2) and held for 5 seconds. Then, the switch on channel Y2 of relay switch module A is switched to the normally closed contact (NCA2) and held for 5 seconds. Then, the switch on channel X3 of relay switch module B is switched to the normally closed contact (NCB3). The above operation is repeated until the above switching action has traversed all channels of relay switch module A and relay switch module B. The peak voltage on the corresponding channel of sensing electrodes E1 to E25 acquired by the computer is extracted, as well as the peak current corresponding to each switch being switched to the normally open contact.
[0020] The beneficial effects of this invention are:
[0021] 1. Improved data acquisition efficiency: This invention integrates the composite channel switching module, excitation signal adjustment module, data acquisition module, and sensing electrode module into the same measuring device, enabling a single device to simultaneously perform resistivity / impedance dual-modal tomographic measurements, significantly improving the acquisition efficiency of electrical tomographic detection data of soil seepage channels.
[0022] 2. Reduced hardware and labor costs: Traditional methods require two separate ERT and EIT devices, along with corresponding sensing electrodes and cables. This invention, however, requires only one device to complete dual-modal detection, significantly reducing hardware costs. Simultaneously, the reduced number and complexity of devices also lowers human resource costs during the observation process.
[0023] 3. Improved detection accuracy: By combining the advantages of resistivity tomography and electrical impedance tomography, this invention can more comprehensively characterize the features of soil seepage channels, thus improving detection accuracy. Resistivity tomography has a good ability to characterize the interior of structures, while electrical impedance tomography has high resolution for anomalies in boundary areas. The combination of the two can achieve fine characterization and identification of soil seepage channels.
[0024] 4. Enhanced technical practicality: The measuring device of this invention has a compact structure and is easy to operate. It is suitable for soil seepage channel detection tasks in various complex environments, and provides strong technical support for carrying out fine characterization and identification of soil seepage channels by resistivity / impedance dual-mode fusion. It is of great significance for ensuring the safety and stability of soil and rock structure infrastructure such as dams. Attached Figure Description
[0025] Figure 1 This is a schematic diagram of the overall structure of the dual-modal tomographic imaging measurement device for soil seepage channel resistivity or impedance according to the present invention.
[0026] Figure 2 This is a resistivity tomography potential cloud map of the dual-mode tomography measurement device for soil seepage channel resistivity or impedance of the present invention.
[0027] Figure 3 This is a potential cloud map of the impedance tomography measurement device for the resistivity or impedance dual-mode tomography measurement of soil seepage channels according to the present invention. Detailed Implementation
[0028] The present invention will be further described below.
[0029] like Figure 1 As shown, the dual-modal tomographic measurement device for resistivity or impedance of soil seepage channels includes an excitation signal conditioning module, a data acquisition module, a channel switching module, a sensing electrode module, and a computer.
[0030] The excitation signal conditioning module mainly consists of a signal generation module and an isolating switch QS. The signal generation module is used to provide the periodic excitation electrical signal required for resistivity or impedance tomography, while the isolating switch QS is adjusted to a closed state to provide a zero potential boundary around the area to be measured when conducting resistivity tomography.
[0031] The data acquisition module mainly consists of a power analysis module, a multi-channel synchronous acquisition module, a signal conditioning module, and a phase-locked loop (PLL) amplifier module. The power analysis module is connected to the signal generation module via wires and data transmission lines, and is used to acquire the excitation voltage signal and the main circuit current signal. The multi-channel synchronous acquisition module acquires the voltage signals of each channel corresponding to the sensing electrode. The signal conditioning module performs amplification and other preprocessing on the raw voltage signals of each channel to ensure that these signals can be correctly interpreted and used by the subsequent multi-channel synchronous acquisition module. The PLL amplifier module is mainly used to enhance the target signal and suppress noise, improving the quality of the voltage signal. The multi-channel synchronous acquisition module is connected to the signal conditioning module via data transmission lines, and the signal conditioning module is connected to the PLL amplifier module via data transmission lines.
[0032] The channel switching module mainly consists of relay switch module A and relay switch module B. Each relay has multiple channels, and each channel includes three general-purpose ports: normally open (NO), common (COM), and normally closed (NC). The normally closed (NCA) terminals of relay switch module A are connected to the phase-locked amplifier module via wires. All normally open (NOA) terminals of relay switch module A are connected in series via wires and connected to the positive terminal of the power analysis module. The common (COMA) terminal of relay switch module A is connected to the normally closed (NCB) terminal of relay switch module B via wires. All normally open (NOB) terminals of relay switch module B are connected in series via wires and connected to the negative terminal of the power analysis module. The common (COMB) terminal of relay switch module B is connected to the corresponding channel on the hub.
[0033] The sensing electrode module mainly consists of sensing electrodes and a hub. The sensing electrodes are made of inert electrode materials such as stainless steel or graphite and are connected to the corresponding channels of the hub via wires. Finally, the GND of the multi-channel synchronous acquisition module is connected to the negative terminal of the power analysis module.
[0034] The signal generation module, data acquisition module, and channel switching module are connected to the computer via data transmission lines. Channel switching control and data acquisition processing are achieved through the host computer software on the computer.
[0035] Measurement steps:
[0036] S1. Measurement Preparation. Connect each module and the deployed sensing electrodes via data transmission lines and wires. Test the communication status between the computer and each module, set the excitation signal parameters and data acquisition frequency via the computer, and import the pole running file for switching modules via the control channel.
[0037] S2. Resistivity Tomography Test. Close the isolating switch QS and connect the negative terminal of the power analysis module to the conductive copper foil around the test area via a wire. Set the output voltage of the signal generation module to a rectangular pulse signal. Set all switches of relay switch module B to normally closed contacts (NCB). After starting the polarization test, control the switch on channel Y1 of relay switch module A to normally open contact (NOA1) and maintain it for 5 seconds, then control the switch on channel Y1 of relay switch module A to normally closed contact (NCA1) and maintain it for 2 seconds. Subsequently, control the switch on channel Y2 of relay switch module A to normally open contact (NOA2) and maintain it for 5 seconds, then control the switch on channel Y2 of relay switch module A to normally closed contact (NCA2) and maintain it for 2 seconds. Repeat the above operation until the above switching action has traversed all channels of relay switch module A. Extract the peak voltage on the corresponding channel of sensing electrodes E1 to E25 obtained by the computer, and the peak current corresponding to each switch being set to the normally open contact. Taking the data collected when the switch on channel Y21 of relay switch module A is switched to the normally open contact (NOA21) as an example, the potential response cloud diagram in the detection area is as follows: Figure 2 As shown.
[0038] S3. Electrical Impedance Tomography Test. Disconnect the isolating switch QS, set the output voltage of the signal generation module to a sinusoidal pulse signal, and reset the switches of relay switch modules A and B to normally closed (NC) contacts. Taking adjacent excitation mode as an example, after starting to execute the pole running file, control the switch on the X2 channel of relay switch module B to the normally open contact (NOB2) and maintain it for 10 seconds. Then control the switch on the Y1 channel of relay switch module A to the normally open contact (NOA1) and maintain it for 5 seconds. After that, control the switch on the Y1 channel of relay switch module A to the normally closed contact (NCA1) and maintain it for 5 seconds. Finally, control the switch on the X2 channel of relay switch module B to the normally closed contact (NCB2).
[0039] Then, the switch on channel X3 of relay switch module B is switched to the normally open contact (NOB3) and held for 10 seconds. Next, the switch on channel Y2 of relay switch module A is switched to the normally open contact (NOA2) and held for 5 seconds. Then, the switch on channel Y2 of relay switch module A is switched to the normally closed contact (NCA2) and held for 5 seconds. Finally, the switch on channel X3 of relay switch module B is switched to the normally closed contact (NCB3). This process is repeated until the switching action has covered all channels of relay switch modules A and B. The peak voltages on the corresponding channels of sensing electrodes E1 to E25, as well as the peak currents corresponding to each switch being switched to the normally open contact, are extracted from the data collected by the computer. Taking the data collected when the switch on channel X2 of relay switch module B is switched to the normally open contact (NOB2) and the switch on channel Y1 of relay switch module A is switched to the normally open contact (NOA1) as an example, the potential response cloud diagram of the detection area is as follows: Figure 3 As shown.
[0040] This invention proposes a dual-modal tomographic measurement device for resistivity or impedance of soil seepage channels. By integrating a composite channel switching module, an excitation signal adjustment module, a data acquisition module, and a sensing electrode module into a single measurement device, a single system can simultaneously perform resistivity / impedance dual-modal tomographic measurements. This improves the acquisition efficiency of electrical tomographic data for soil seepage channels while reducing hardware and human resource costs during observation. This technology provides technical support for the fine characterization and identification of resistivity / impedance dual-modal resistivity / impedance of soil seepage channels, and is of great significance for ensuring the safety and stability of foundation structures such as dams.
[0041] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A dual modality electrical resistivity or impedance tomography measurement apparatus for soil seepage flow channels, characterized by: The excitation signal adjusting module, the data acquisition module, the channel switching module, the sensing electrode module, and the computer are connected through data transmission lines and wires. The data acquisition module is composed of a power analysis module, a multi-channel synchronous acquisition module, a signal adjusting module, and a lock-in amplification module. The channel switching module is composed of a relay switch module A and a relay switch module B. Each relay has multiple channels, each of which includes a normally open end NO, a common end COM, and a normally closed end NC. The normally closed end NCA of the relay switch module A is connected to the lock-in amplification module through wires. All the normally open ends NOA of the relay switch module A are connected in series through wires and connected to the positive pole of the power analysis module. The common end COMA of the relay switch module A is connected to the normally closed end NCB of the relay switch module B through wires. All the normally open ends NOB of the relay switch module B are connected in series through wires and connected to the negative pole of the power analysis module. The common end COMB of the relay switch module B is connected to the corresponding channel on the hub. The sensing electrode module is composed of sensing electrodes and a hub. The sensing electrodes are made of stainless steel or graphite inert electrode materials and are connected to the corresponding channels on the hub through wires. Finally, the GND of the multi-channel synchronous acquisition module is connected to the negative pole of the power analysis module. The signal generation module, data acquisition module, and channel switching module are connected to the computer through data transmission lines. Channel switching control and data acquisition processing are realized through the upper computer software on the computer side.
2. The soil permeation channel resistivity or electrical impedance dual- modal tomographic measurement apparatus according to claim 1, characterized in that: The signal generation module provides the periodic excitation electrical signal required in resistivity or electrical impedance tomography detection. The isolation switch QS is used to adjust to the closed state to provide a zero potential boundary around the measured area when conducting resistivity tomography detection.
3. The electrical resistivity or electrical impedance dual modal tomographic measurement apparatus for soil seepage flow channels of claim 2, wherein: The power analysis module is connected to the signal generation module through wires and data transmission lines for collecting excitation voltage signals and main circuit current signals. The multi-channel synchronous acquisition module is used to collect voltage signals from each channel corresponding to the sensing electrode. The signal adjusting module is used to amplify and preprocess the original voltage signals from each channel. The lock-in amplification module is mainly used to enhance the target signal and suppress noise, improving the quality of the voltage signal. The multi-channel synchronous acquisition module is connected to the signal adjusting module through data transmission lines, and the signal adjusting module is connected to the lock-in amplification module through data transmission lines.
4. The electrical resistivity or electrical impedance dual modal tomographic measurement apparatus for soil seepage flow channels of claim 3, wherein: It also includes a measurement step: S1, measurement preparation; connect each module and the sensing electrode through data transmission lines and wires; test the communication status between the computer and each module, set the excitation signal parameters and data acquisition frequency through the computer, and import the running electrode file to control the channel switching module; S2, resistivity tomography test; close the isolation switch QS and connect the negative pole of the power analysis module to the conductive copper foil around the measured area through wires. The output voltage of the signal generation module is set as a rectangular pulse signal; all switches of the relay switch module B are set to the normally closed contact NCB; after starting to execute the running pole file, the switch on the Y1 channel of the relay switch module A is set to the normally open contact NOA1 and maintained for 5S, and then the switch on the Y1 channel of the relay switch module A is set to the normally closed contact NCA1 and maintained for 2S; then the switch on the Y2 channel of the relay switch module A is set to the normally open contact NOA2 and maintained for 5S, and then the switch on the Y2 channel of the relay switch module A is set to the normally closed contact NCA2 and maintained for 2S; the above-mentioned switch switching actions are repeated until all channels of the relay switch module A are traversed; the peak voltage on the corresponding channel of the E1 to E25 sensing electrodes obtained by the computer acquisition is extracted, and the peak current corresponding to each time when the switch is set to the normally open contact is extracted; S3, electrical impedance tomography test; disconnect the isolation switch QS, set the output voltage of the signal generation module as a sine pulse signal, reset the switches of the relay switch module A and the relay switch module B to the normally closed NC contact; after starting to execute the running pole file, the switch on the X2 channel of the relay switch module B is set to the normally open contact NOB2 and maintained for 10S, then the switch on the Y1 channel of the relay switch module A is set to the normally open contact NOA1 and maintained for 5S, and then the switch on the Y1 channel of the relay switch module A is set to the normally closed contact NCA1 and maintained for 5S, and then the switch on the X2 channel of the relay switch module B is set to the normally closed contact NCB2; then the switch on the X3 channel of the relay switch module B is set to the normally open contact NOB3 and maintained for 10S, then the switch on the Y2 channel of the relay switch module A is set to the normally open contact NOA2 and maintained for 5S, and then the switch on the Y2 channel of the relay switch module A is set to the normally closed contact NCA2 and maintained for 5S, and then the switch on the X3 channel of the relay switch module B is set to the normally closed contact NCB3; the above-mentioned switch switching actions are repeated until all channels of the relay switch module A and the relay switch module B are traversed; the peak voltage on the corresponding channel of the E1 to E25 sensing electrodes obtained by the computer acquisition is extracted, and the peak current corresponding to each time when the switch is set to the normally open contact is extracted.
Citation Information
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Capacitance / electromagnetic dual-mode imaging measurement system based on LCR meter / impedance analyzer
CN110186999A