Detection and testing methods based on a model device for groundwater seepage channels in gold tailings ponds

Abstract

This invention relates to the field of tailings dam model construction and electrical resistivity detection technology, and particularly to a detection test method based on a model device for groundwater seepage channels in a gold tailings dam. First, a model device is constructed, including a tank, an insulating plate on the inner wall of the tank, a layered simulated medium filling the tank, layered water injection components and high-density resistivity detection components within the tank. Multiple parallel high-density resistivity measurement lines are laid out, and the electrodes and acquisition instruments are wired. Electrode grounding performance is verified, and a grounding resistance threshold is set to screen electrode conductivity. Different seepage conditions are simulated through multi-gradient quantitative water injection using the layered water injection components. After the seepage stabilizes, various electrical resistivity devices are switched to collect raw electrical data, which is preprocessed to obtain inversion base data. Finally, the dataset is imported into inversion software, and a fitting error threshold is set to iteratively invert the data from multiple devices, outputting a resistivity inversion imaging map to achieve imaging and identification of groundwater seepage channels in the tailings dam.

Description

Technical Field

[0001] This invention relates to the field of tailings dam model construction and electrical detection technology, and in particular to a detection test method based on a model device for groundwater seepage channels in gold tailings dams. Background Technology

[0002] Tailings ponds are critical facilities for storing tailings in gold mines, and their safety and environmental protection directly affect mine operations and the surrounding ecosystem. During the tailings storage process, factors such as self-weight compaction and erosion by seepage water can easily create groundwater seepage channels in the pond area and surrounding fracture zones and faults. These seepage channels can lead to the leakage of leachate from the tailings pond, carrying pollutants such as heavy metals and residual chemicals from mineral processing, polluting surrounding groundwater and surface water, violating mandatory standards such as the "Groundwater Quality Standard" and the "Technical Specification for Pollution Prevention and Control of Tailings Ponds." Against the backdrop of accelerated green mine construction and increasingly stringent environmental policies, the rigid requirements for groundwater monitoring, risk assessment, and hazard investigation in tailings ponds have been further clarified. Therefore, the research and application of groundwater seepage channel detection devices and methods are increasingly urgent, as they serve as core technical tools for accurately identifying hazards and optimizing prevention and control plans.

[0003] At present, the detection of groundwater seepage channels in gold tailings ponds mainly relies on field drilling, conventional geophysical exploration and simple seepage tests, which have many technical defects: (1) Drilling is costly and time-consuming, and it is difficult to fully depict the spatial distribution of seepage channels; (2) Conventional geophysical exploration methods can only qualitatively identify abnormal areas and cannot quantitatively obtain the location and shape of seepage channels; (3) Existing indoor simulation test devices are mostly general-purpose and have not been adapted to the working conditions of gold tailings, making it difficult to reproduce the field seepage environment. Furthermore, they have not systematically integrated the three high-density resistivity devices of Wenner, dipole and Schlumberger, and lack a systematic comparative analysis of the detection effects of the three devices, making it difficult to provide accurate device selection basis for field detection.

[0004] In view of this, there is an urgent need to design an experimental device and method for detecting groundwater seepage channels in tailings ponds in the gold industry in order to solve the above problems. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a detection and testing method based on a model device for groundwater seepage channels in gold tailings ponds.

[0006] The purpose of this invention is to provide a detection and testing method based on a model device for groundwater seepage channels in gold tailings ponds, comprising the following steps: S1. Construct a model device for the groundwater seepage channel of a gold tailings dam. The model device includes a tank, an insulating plate on the inner wall of the tank, a simulated medium filled in layers inside the tank, water injection components arranged in layers inside the tank, and a high-density resistivity detection component. After assembly, multiple parallel high-density resistivity measurement lines are laid out inside the simulated medium and the electrodes and acquisition instruments are connected. S2. Conduct pre-electrode verification, debug and optimize the contact state between the electrodes and the simulated medium, and set the grounding resistance judgment threshold to complete the full line electrode continuity screening. S3. Multi-gradient quantitative water injection is carried out through the water injection component to simulate different seepage conditions. After the seepage stabilizes, multiple high-density electrical resistivity devices are switched to collect raw electrical data, and the inversion basic dataset is obtained after preprocessing. S4. Import the inversion basic dataset into the inversion software, set the fitting error threshold, and independently iterate the inversion of data for each type of device, output the corresponding resistivity inversion imaging map, and complete the seepage channel imaging analysis.

[0007] Preferably, in step S1, the simulated medium is divided into three layers from bottom to top: a coarse sand layer, a medium sand layer, and a fine sand layer; the water injection component includes a water injection pipe located in the fine sand layer and a pre-embedded pipe located in the medium sand layer; the high-density resistivity detection component includes an electrode, a cable, and a high-density resistivity transducer, and the electrode is electrically connected to the high-density resistivity transducer via the cable.

[0008] Preferably, the simulated medium in the tank has a total filling height of 0.8~1.2m; 8 parallel measuring lines are laid out, with 30 electrodes evenly arranged on each measuring line, the distance between adjacent electrodes is 0.1m, and the vertical burial depth of the electrodes is 0.2~0.3m; an overflow outlet is opened on the side wall of the tank, and a filter outlet is opened at the bottom.

[0009] Preferably, in step S2, the grounding resistance determination threshold is 10kΩ.

[0010] Preferably, before the water injection test in step S3, a background electrical property assessment step is also included: high-density electrical resistivity tomography self-test data collection is carried out under the initial filling state, the electrical difference quantification index is statistically analyzed, data correction and noise reduction processing is completed using dedicated software, electrical cross-sectional images are generated, the electrical distribution law of the original medium of the model is determined, and a background benchmark is established.

[0011] Preferably, the collected data includes apparent resistivity, potential difference, grounding resistance, natural potential, and abnormal characteristic values ​​at each measuring point; The quantitative indicators of electrical differences include resistivity range, resistivity average, data standard deviation, electrical anomaly amplitude, and electrical anomaly gradient. The raw data is preprocessed, filtered for noise reduction, and abnormal feature extraction is performed to remove invalid measurement points caused by poor grounding, electromagnetic interference, and electrode contact defects.

[0012] Preferably, in step S3, the water injection gradient is set to five levels: 100mL, 200mL, 500mL, 1000mL, and 1500mL. After each level of water injection is completed, the water is left to stand for no less than 30 minutes to allow the seepage to stabilize.

[0013] Preferably, in step S4, the inversion software is RES2DINV, and 5% is set as the termination threshold for iterative fitting error. Least squares iterative inversion is carried out on the datasets of the three types of devices: Wenner, Dipole, and Schlumberger, and it is continued until the overall fitting error is lower than 5%.

[0014] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention constructs a layered physical simulation device adapted to gold tailings dams. The entire inner wall of the tank is covered with insulating plates to eliminate conductive interference from the metal tank. Through two sets of layered, fixed-point water injection components—shallow injection pipes and deep pre-embedded pipes—it accurately simulates two typical on-site leakage conditions: shallow surface seepage and deep mid-layer seepage in tailings. It fully reproduces the seepage development law of multi-layered heterogeneous aquifers in tailings, overcoming the shortcomings of traditional general-purpose simulation devices that cannot match the actual seepage environment of gold tailings and have limited water injection conditions. The device adopts a modular assembly structure; the simulation medium, electrodes, and pipelines can all be disassembled and reset, enabling repeated parallel comparative tests under multiple gradients and conditions, resulting in strong test reusability. The detection system integrates three high-density resistivity observation devices: Wenner, dipole, and Schlumberger. It can quickly switch device types to simultaneously complete electrical data acquisition under the same model and seepage conditions. Equipped with standardized high-density electrical resistivity acquisition equipment and integrated data processing software, a single device can simultaneously achieve the entire process of seepage physical simulation, multi-device electrical detection, data correction, and inversion imaging.

[0015] Based on high-density resistivity detection technology, this method leverages the inherent electrical differences between the high resistivity of dry / dense tailings media and the low resistivity of saturated seepage channels to identify and characterize seepage channels. An innovative pre-injection process assesses the background electrical properties of the media, establishing a native electrical benchmark through multi-dimensional quantitative electrical indicators. This effectively eliminates interference from inherent high and low resistivity anomalies caused by uneven media loading, preventing confusion between the native media's electrical characteristics and low-resistivity seepage channels, and significantly reducing the probability of misjudging seepage boundaries. During the experiment, multiple sets of repeated measurements were performed on a single measuring line, a single device, and a single injection gradient. Standardized preprocessing methods such as mean denoising, outlier removal, grounding resistance correction, and Vp parameter correction were used to reduce data distortion caused by environmental electromagnetic interference and poor electrode contact, thereby improving the reliability of the original electrical data.

[0016] By comparing the detection results of the three types of devices under the same conditions, the imaging resolution capabilities of different devices for shallow and deep seepage can be quantitatively evaluated. This provides a physical test basis for device selection and data interpretation for on-site detection of potential leakage hazards in gold tailings ponds in the field, improves the accuracy of locating and characterizing groundwater seepage channels in tailings ponds, and provides reliable technical support for risk investigation and long-term safety monitoring of mine tailings ponds. Attached Figure Description

[0017] Figure 1 This is a plan view of the electrode layout of the groundwater seepage channel model device for a gold tailings dam provided in an embodiment of the present invention.

[0018] Figure 2 This is a side elevation sectional view of a model device for groundwater seepage channels in a gold tailings dam provided in an embodiment of the present invention.

[0019] Figure 3 This is a front sectional view of a model device for groundwater seepage channels in a gold tailings dam provided in an embodiment of the present invention.

[0020] Figure 4 This is a physical diagram of a model device for groundwater seepage channels in a gold tailings dam, provided in an embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of the original apparent resistivity of the dipole device provided in an embodiment of the present invention.

[0022] Figure 6 This is a schematic diagram of the original apparent resistivity of the Wenner device provided in an embodiment of the present invention.

[0023] Figure 7 This is a schematic diagram of the original apparent resistivity of the Schlumberger device provided in an embodiment of the present invention.

[0024] Figure 8 This is a two-dimensional resistivity inversion imaging diagram of a dipole device provided in an embodiment of the present invention.

[0025] Figure 9 This is a two-dimensional resistivity inversion imaging diagram of the Wenner device provided in an embodiment of the present invention.

[0026] Figure 10 A two-dimensional resistivity inversion imaging diagram of the Schlumberger device provided in an embodiment of the present invention.

[0027] Figure 11 A schematic diagram of the three-dimensional resistivity spatial distribution model of the groundwater seepage channel in a gold tailings dam, provided in an embodiment of the present invention.

[0028] Figure label: 1. Tank body; 2. Insulating board; 3. High-density electrical resistivity tomography (EDT) instrument; 4. Water injection pipe; 5. Electrodes; 6. Cables; 8. Overflow outlet; 9. Embedded pipes; 10. Valves; 11. Water filter outlet 12. Fine sand; 13. Medium sand; 14. Coarse sand. Detailed Implementation

[0029] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0031] This invention provides a detection and testing method based on a model device for groundwater seepage channels in gold tailings ponds, specifically including the following steps: S1. Construct a model device for groundwater seepage channels in a gold tailings dam: See Figures 1-4 A model device for the groundwater seepage channel in a gold tailings dam was constructed, including a tank 1, an insulating plate 2, a high-density electrical resistivity tomography (E tomography) instrument 3, a water injection pipe 4, electrodes 5, cables 6, an overflow outlet 8, a pre-embedded pipe 9, valves 10, a filter outlet 11, fine sand 12, medium sand 13, and coarse sand 14. The overall construction steps and structural details are as follows: Construct tank 1, with an external outline of 4.6m in length, 3.6m in width, and 1.5m in height, and an internal effective cavity with a length of 4m and a width of 3m; cover all inner sidewalls and bottom walls of tank 1 with insulating board 2, and seal all joints of insulating board 2 and the connection between the insulating board and tank 1 to eliminate conductive interference from the metal sidewalls of the tank and form a sealed, insulated, and leak-proof inner cavity; Coarse sand 14, medium sand 13, and fine sand 12 are filled into the inner cavity enclosed by the insulating plate 2 from bottom to top. After each layer is filled, it is compacted and leveled to simulate the multi-layer heterogeneous water-bearing layer of the gold tailings dam. The medium of each layer is kept at a similar filling moisture content. The total filling height of coarse sand 14, medium sand 13, and fine sand 12 is about 1m. Two water injection pipes 4 are horizontally installed through the side wall of the tank 1 at the elevation of the fine sand 12. The water injection pipes 4 serve as fixed-point water injection components. The external pipeline is connected to the water supply equipment, which can quantitatively deliver water into the sand layer to simulate the formation of shallow concentrated seepage channels by large-area seepage of the surface of the gold tailings pond. Two pre-embedded pipes 9 are vertically arranged inside the side wall of the tank 1 at a distance of 65-70cm from the bottom. The pre-embedded pipes 9 are independent vertical pipes with their bottom ends suspended. A valve 10 is installed on the upper end of the pre-embedded pipes 9 that extends outside the tank 1. Water is added at fixed points through the pre-embedded pipes 9 to simulate deep seepage in a gold tailings pond. In some embodiments, two pre-embedded pipes 9 are vertically arranged at a distance of 67cm from the bottom. An overflow outlet 8 is opened on the side wall of the tank body 1 corresponding to the area where coarse sand 14 is laid. The overflow outlet 8 is used to automatically discharge excess water when the water level in the tank exceeds the set height, stabilize the overall reference water level of the aquifer, and prevent the simulated medium from being washed away by the water flow. A filter port 11 with an inner diameter of 50 mm is opened on the bottom side wall of the tank 1. A permeable reverse filter layer is laid on the inner side of the filter port 11 to prevent coarse sand 14, medium sand 13 and fine sand 12 from flowing out of the opening. The filter port 11 can drain all the water in the tank after the test, which is convenient for excavating the actual seepage area. Eight parallel high-density resistivity measuring lines are laid inside the sand. 30 electrodes 5 are evenly spaced on each measuring line. The center-to-center distance between two adjacent electrodes 5 is 0.1m. The electrodes 5 are inserted vertically downwards into the sand layer to a depth of 0.2~0.3m. Cables 6 are connected to the top of all electrodes 5. All cables 6 are led out from the side of the tank. Connect all the cables 6 leading out from the outside to the wiring ports of the high-density electrical resistivity meter 3, check the continuity of the cables section by section, test the grounding resistance of each electrode 5, and adjust the electrode burial depth and compact the surrounding sand to make the grounding resistance of all electrodes less than 10kΩ, thus completing the construction of the entire gold tailings dam groundwater seepage channel model device, which can carry out gradient water injection and multi-device resistivity synchronous detection tests. In some embodiments, the parameters of the high-density electrical resistivity meter 3 include: the cable type is centralized, the electrode running mode is longitudinal, the power supply voltage is 50V, the power supply time is 500ms, the power off time is 50ms, the minimum voltage is 10mV, the minimum current is 5mA, and the electrode spacing is 0.1m; the detection system used adopts three device types: Wenner, dipole, and Schlumberger.

[0032] S2. Electrode Pre-verification: Before data acquisition, grounding performance is tested for each electrode 5. Contact conditions are optimized by adjusting the burial depth of electrode 5 and compacting the surrounding medium. At the same time, the starting and ending electrode numbers of a single test line are entered into the instrument. The grounding resistance over-limit judgment threshold (10kΩ) is set to complete the screening of electrode continuity and grounding performance for the entire test line. After all electrode test indicators meet the test standards, the water injection detection step is started. In some embodiments, the coordinates of the origin and each electrode are recorded, with the origin coordinates being (0, 0) and the first electrode coordinates being (290, 200). Before testing, the grounding resistance of the electrodes within the model is checked for good condition. The first electrode (electrode number 1), the last electrode (electrode number 240), and the over-limit value of 10kΩ are input. If there are no abnormalities, proceed to the next step. Brief description of the principle: The high-density resistivity method relies on the stable conduction of power supply current and the acquisition of potential signals between the electrode and the soil. Poor contact between the electrode and the medium will produce excessive contact resistance, causing potential data distortion, blank / color abnormalities in the cross section, and ultimately leading to the distortion of the identification of the low-resistivity seepage zone. This step is divided into two levels of quality control: (1) By adjusting the electrode burial depth and compacting the surrounding medium, the effective contact area between the electrode and the sand is increased, and the contact resistance is reduced from the physical level; (2) The starting and ending electrode numbers of the survey line are entered to limit the data acquisition range of the instrument and prevent the data misalignment caused by the incorrect electrode number; the grounding resistance exceeding the limit threshold is set as the judgment standard, and the instrument automatically compares the measured resistance with the threshold to quickly locate the electrode with contact failure and eliminate the data interference source in advance.

[0033] S3. Seepage Simulation and Apparent Resistivity Data Acquisition and Processing: Water injection is carried out in layers through the upper injection pipe 4 and the middle pre-buried pipe 9. Multiple injection flow rates are set to simulate shallow and deep seepage development conditions in the tailings. After each injection is completed, the internal seepage field is allowed to stabilize before detection is initiated. In a stable state, the three types of observation devices—Wenner, dipole, and Schlumberger—are sequentially switched to collect raw data on potential difference and power supply current along all measurement lines. The instruments calculate the apparent resistivity in real time and generate raw cross-sectional images. Each measurement line is measured eight times for each set of conditions. After acquisition, multiple sets of data from a single measurement line are processed uniformly to remove abnormal apparent resistivity values ​​caused by poor electrode contact or environmental interference. The average value of the valid measurement data is used as the base dataset for subsequent inversion. In some embodiments, the layered fixed-point water injection adopts a five-level quantitative water addition gradient, with the cumulative water addition volume for a single time set to 100mL, 200mL, 500mL, 1000mL, and 1500mL respectively. After each gradient water addition is completed, the water is allowed to stand for more than 30 minutes to ensure that the water is fully diffused and forms a stable seepage channel. Gradient water addition tests are carried out at the deep middle layer corresponding to the pre-embedded pipe and the shallow surface layer corresponding to the water injection pipe, and the actual excavated dimensions and seepage volume of the seepage area under each gradient are recorded simultaneously. After the seepage stabilized, the transverse diameter and vertical development height of the water-infiltrated zone were measured on-site. The statistics of the infiltrated dimensions corresponding to the cumulative water addition for each group are shown in Table 1.

[0034] Table 1 Measured dimensions of the infiltration zone under different water injection volumes

[0035] For each survey line, complete raw apparent resistivity data were collected for three types of devices. One survey line was selected as a typical example, and apparent resistivity diagrams for the dipole device, the Wenner device, and the Schlumberger device were generated. These three types of raw cross-sections visually represent the spatial distribution of resistivity within the model under different devices, as well as the morphology and boundary differences of the low-resistivity anomaly region caused by saturated seepage. The raw cross-sections serve as a direct reference for data preprocessing and outlier removal. The results are shown in […]. Figure 5 , Figure 6 and Figure 7 .

[0036] Before conducting the experiment, the steps also include evaluating the electrical differences within the model device of the groundwater seepage channel in the gold tailings dam. Specifically, high-density electrical resistivity tomography (EPT) is performed under the initial filling state to collect data, statistically analyze the quantitative indicators of electrical differences, use specialized software to complete data correction and noise reduction, generate electrical cross-sectional images, determine the electrical distribution law of the original medium in the model, establish a baseline, and eliminate the interference of uneven medium filling on the results of subsequent seepage tests. The collected data includes apparent resistivity values ​​at each measuring point, potential differences between electrodes, grounding resistance of a single electrode, natural potential values, and cross-sectional electrical anomaly characteristic values. Quantitative indicators of electrical differences include resistivity range, average resistivity, data standard deviation, electrical anomaly amplitude, and electrical anomaly gradient. Data processing software is used to preprocess the raw data, perform filtering and noise reduction, and extract anomaly features, eliminating invalid measuring points caused by poor grounding, electromagnetic interference, and electrode contact defects. Specific processing operations include: shielding of abnormal electrodes, re-measuring and supplementing single-point / local area data, smoothing and noise reduction of the entire data range, and Vp anomaly detection. Correction and grounding resistance deviation correction; electrical cross-sectional images include apparent resistivity schematic diagrams and inverted resistivity imaging diagrams; the images intuitively reflect the spatial distribution of resistivity inside the model, identifying the location, shape, and distribution range of the original high-resistivity and low-resistivity bodies; by comparing the inversion results of different detection devices, different burial depths, and multiple measuring lines, the overall initial electrical differences of the model are comprehensively evaluated, and the electrical boundary threshold characteristics of dense areas, loose areas, original saturated areas, and dry areas are divided, providing a baseline reference for subsequent seepage channel identification, medium zoning determination, and comparative analysis of test results under water injection conditions.

[0037] S4. Two-dimensional inversion of apparent resistivity data: Import the basic dataset of apparent resistivity processed in S3 into the RES2DINV professional inversion software, and simultaneously input the pre-calibration information such as electrode coordinates, model geometric dimensions, and layered medium parameters; the software automatically identifies and removes residual discrete distortion measurement points, and completes the apparent resistivity numerical correction by combining the environmental moisture content and medium temperature recorded in the test. A 5% threshold was set as the termination threshold for the inversion fitting error. Least squares iterative inversion calculations were performed independently on the datasets of the Wenner, Dipole, and Schlumberger devices. The program continued iterative calculations until the overall fitting error was below 5%. If the error was still higher than the threshold after iteration, further iterations were performed. After the inversion calculations were completed, two-dimensional resistivity inversion images corresponding to the three types of devices were output. The inversion images can correct shallow distortions of the original apparent resistivity cross-section, weaken edge measurement errors, and accurately restore the true burial depth, spatial morphology, development thickness, and low-resistivity anomaly boundaries of the seepage channels within the model. The process was performed on the three types of devices. (1) Resistivity inversion mapping of dipole device: The detection was completed according to the experimental method of fixed-point and quantitative water addition to the pre-embedded pipe and surface water addition to the water injection pipe. The collected and pre-processed apparent resistivity data was imported into the software to complete the iterative inversion and obtain the resistivity inversion results of the dipole device and its imaging map, see Figure 8 ; (2) Resistivity inversion mapping of the Wenner device: The measuring line was set up and the water injection detection was completed according to the test method of fixed-point and quantitative water addition through pre-buried pipes. Apparent resistivity data was collected using the Wenner device. After software inversion, the resistivity inversion results of the Wenner device and its imaging map were obtained, as shown in the figure. Figure 9 ; (3) Resistivity inversion mapping of the Schlumberger device: The measuring line was laid out and the water injection detection was completed according to the test method of fixed-point and quantitative water addition through pre-buried pipes. Apparent resistivity data was collected using the Schlumberger device. After software inversion, the resistivity inversion results of the Schlumberger device and its imaging map were obtained, as shown in the figure. Figure 10 ; In some embodiments, Geogiga RImager software can be used in conjunction with RES2DINV to perform data correction and inversion calculations. After the inversion is completed, the resistivity extremes, anomalous area, and seepage center burial depth of the inversion section of each type of device are exported synchronously for subsequent comparative analysis of device detection accuracy.

[0038] Two-dimensional resistivity inversion images from all survey lines were uniformly imported into 3D visualization modeling software. Multi-coordinate matching was performed based on electrode coordinates and model dimensions. Spatial interpolation algorithms were used to encrypt and fill the resistivity data in blank areas between survey lines, constructing a full-domain 3D resistivity data volume. Saturated low-resistivity seepage anomalies were extracted using resistivity threshold filtering, and a 3D spatial distribution model of groundwater seepage channels in gold tailings was rendered. This model visually demonstrates the overall three-dimensional distribution, burial depth, and lateral and longitudinal development characteristics of the seepage channels under different water injection conditions. The 3D seepage channel model is shown below. Figure 11 .

[0039] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0040] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A detection and testing method based on a model device for groundwater seepage channels in gold tailings ponds, characterized in that: Includes the following steps: S1. Construct a model device for the groundwater seepage channel in a gold tailings dam. The model device includes a tank, an insulating plate on the inner wall of the tank, a simulated medium filled in layers inside the tank, water injection components arranged in layers inside the tank, and a high-density resistivity detection component. After assembly, multiple parallel high-density resistivity measurement lines are laid out inside the simulated medium, and the electrodes and acquisition instruments are wired. S2. Conduct pre-electrode verification, debug and optimize the contact state between the electrodes and the simulated medium, and set the grounding resistance judgment threshold to complete the full line electrode continuity screening. S3. Multi-gradient quantitative water injection is carried out through the water injection component to simulate different seepage conditions. After the seepage stabilizes, multiple high-density electrical resistivity devices are switched to collect raw electrical data, and the inversion basic dataset is obtained after preprocessing. S4. Import the inversion basic dataset into the inversion software, set the fitting error threshold, and independently iterate the inversion of data for each type of device, output the corresponding resistivity inversion imaging map, and complete the seepage channel imaging analysis.

2. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 1, characterized in that: In step S1, the simulated medium is divided into three layers from bottom to top: a coarse sand layer, a medium sand layer, and a fine sand layer; the water injection component includes a water injection pipe located in the fine sand layer and a pre-embedded pipe located in the medium sand layer; the high-density resistivity detection component includes an electrode, a cable, and a high-density resistivity meter, and the electrode is electrically connected to the high-density resistivity meter via the cable.

3. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 2, characterized in that: The simulated medium inside the tank has a total filling height of 0.8~1.2m; 8 parallel measuring lines are laid out, with 30 electrodes evenly arranged on each measuring line, the distance between adjacent electrodes is 0.1m, and the vertical burial depth of the electrodes is 0.2~0.3m; an overflow outlet is opened on the side wall of the tank, and a filter outlet is opened at the bottom.

4. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 1, characterized in that: In step S2, the grounding resistance determination threshold is 10kΩ.

5. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 1, characterized in that: Before the water injection test in step S3, a background electrical property assessment step is also included: high-density electrical resistivity tomography self-test data collection is carried out under the initial filling state, the electrical difference quantification index is statistically analyzed, data correction and noise reduction processing is completed using dedicated software, electrical cross-sectional images are generated, the electrical distribution law of the original medium of the model is determined, and a background benchmark is established.

6. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 5, characterized in that: The collected data includes apparent resistivity, potential difference, grounding resistance, natural potential, and abnormal characteristic values ​​at each measuring point; The quantitative indicators of electrical differences include resistivity range, resistivity average, data standard deviation, electrical anomaly amplitude, and electrical anomaly gradient. The raw data is preprocessed, filtered for noise reduction, and abnormal feature extraction is performed to remove invalid measurement points caused by poor grounding, electromagnetic interference, and electrode contact defects.

7. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 1, characterized in that: In step S3, the water injection gradient is set to five levels: 100mL, 200mL, 500mL, 1000mL, and 1500mL. After each level of water injection is completed, the water is left to stand for no less than 30 minutes to allow the seepage to stabilize.

8. The detection and testing method based on the groundwater seepage channel model device of a gold tailings dam according to claim 1, characterized in that: In step S4, the inversion software uses RES2DINV, and 5% is set as the termination threshold for iterative fitting error. Least squares iterative inversion is carried out on the datasets of the three types of devices: Wenner, Dipole, and Schlumberger, and it is continuously iterated until the overall fitting error is lower than 5%.

Images