Penetration risk analysis and identification system for covering layer of deep ice water accumulation body

Abstract

The invention provides a penetration risk analysis and identification system for a covering layer of a deep ice water accumulation body, and relates to the technical field of rock-soil body analysis. The system comprises a test module, a control module, a data processing module and a result analysis module, wherein the test module is used for executing various types of tests on a sample of a deep ice water accumulation body covering layer; the control module is electrically connected with the test module and is used for setting test parameters according to the test type of the test; the test module carries out tests of corresponding types on the samples according to the test parameters and records test results, and the test results comprise intermediate parameters; the data processing module is electrically connected with the test module and the control module and is used for acquiring test parameters and intermediate parameters and calculating target parameters according to the test parameters and the intermediate parameters; and the result analysis module is electrically connected with the data processing module and is used for generating a seepage failure characteristic curve and a performance summary sheet according to the test parameters and the target parameters. The system can improve the comprehensiveness of result analysis.

Description

Technical Field

[0001] The present disclosure relates to the technical field of rock and soil analysis, and in particular to a system for analyzing and identifying the seepage risk of overburden of a thick ice-water accumulation body. Background Art

[0002] In water conservancy and hydropower engineering, the seepage damage problem of dam foundation rock and soil has always been an important research topic. The current seepage damage research is mainly carried out on ordinary rock and soil or deep overburden, and there is no research on the analysis and identification of the seepage damage risk in the special rock and soil such as ice-water accumulation overburden.

[0003] At present, the research on seepage damage of rock and soil mainly includes the study of seepage characteristics, the acquisition of soil seepage parameters and the exploration of the conditions for the occurrence of seepage damage, etc. However, these studies often have a wide variety of tests, insufficient refinement of the test process analysis, and usually only a single test is carried out, and the result analysis lacks comprehensiveness.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The present invention provides a system for analyzing and identifying the seepage risk of a thick ice-water accumulation body overburden, which can improve the comprehensiveness of the result analysis.

[0006] According to one aspect of the present disclosure, a system for analyzing and identifying the seepage risk of a deep ice-water accumulation body overburden is provided, comprising:

[0007] A test module for performing various types of tests on samples of deep ice-water deposits, including coarse particle property tests, fine particle grading tests, permeability tests, disintegration tests, permeability damage tests, and contact scour tests of different strata;

[0008] A control module, electrically connected to the test module, for setting test parameters according to the test type of the test; the test module performs a corresponding type of test on the sample according to the test parameters, and records the test results, which include intermediate parameters;

[0009] a data processing module, electrically connected to the test module and the control module, and configured to obtain the test parameters and the intermediate parameters, and calculate the target parameters according to the test parameters and the intermediate parameters;

[0010] The result analysis module is electrically connected to the data processing module and is used to generate a penetration damage characteristic curve and a performance summary table according to the test parameters and the target parameters.

[0011] In an exemplary embodiment of the present disclosure, the test parameters include one or more of the dry mass, volume, test time, head difference, overburden pressure, particle size, area, initial height, and initial fine particle mass of the sample; the intermediate parameters include one or more of the seepage path length corresponding to the head difference, seepage flow, variable head pipe cross-sectional area, lost fine particle mass, and sample sedimentation height; the target parameters include the dry density, hydraulic gradient, infiltration flow rate, permeability coefficient, and fine particle loss rate of the sample.

[0012] In an exemplary embodiment of the present disclosure, the fine particle grading test includes:

[0013] The particle size distribution in the fine particles is measured by sieve analysis.

[0014] In an exemplary embodiment of the present disclosure, the method of measuring the particle size distribution in the fine particles by sieving analysis includes:

[0015] Using a plurality of sieves with different apertures, sifting the sample in order from large to small apertures;

[0016] After sieving, weigh the mass of the particles remaining on each sieve.

[0017] In an exemplary embodiment of the present disclosure, the penetration test includes:

[0018] The sample is loaded into a sample tube of the permeameter, a water head controller of the permeameter is connected to the control module, and the water head of the permeameter is set by the control module;

[0019] Slowly add water from the bottom to fully saturate the sample and expel air;

[0020] Record the initial water head height;

[0021] Open the water outlet and record the water head height every 30 minutes.

[0022] In an exemplary embodiment of the present disclosure, the disintegration test comprises:

[0023] placing the sample in an immersion container and allowing water to submerge the sample;

[0024] Using a disintegrator to perform rotational disintegration on the soaked sample;

[0025] The infiltration risk analysis and identification system also includes a camera device, which is used to take photos or videos at preset time intervals to record the disintegration amount at different time points.

[0026] In an exemplary embodiment of the present disclosure, the penetration damage test includes:

[0027] Adjusting the particle size distribution of the sample according to the test range of the permeameter so that the particle size distribution of the sample conforms to the test range of the permeameter;

[0028] Conducting a permeability failure test on the sample after adjusting the particle gradation, and simulating the permeability behavior under different working conditions by controlling the hydraulic gradient and the overburden pressure;

[0029] The test time, the hydraulic gradient, the seepage rate, the mass of the lost fine particles and the sample settling height are recorded by the control module.

[0030] In an exemplary embodiment of the present disclosure, adjusting the particle size distribution of the sample according to the test range of the permeameter includes:

[0031] The particle size distribution of the sample is adjusted by using elimination method, skeleton replacement method, translation reduction method, discontinuous elimination method or lower envelope method.

[0032] In an exemplary embodiment of the present disclosure, the penetration risk analysis and identification system further includes:

[0033] A storage device is electrically connected to the data processing module and the result analysis module, and is used to store the test parameters, the intermediate parameters, the target parameters, the calculation formulas in the calculation process, and the pictures and videos obtained by the camera device.

[0034] In an exemplary embodiment of the present disclosure, the system further includes:

[0035] The display component includes a display capable of displaying the penetration damage characteristic curve and the performance summary table.

[0036] The disclosed deep ice-water accumulation body overburden seepage risk analysis and identification system realizes a comprehensive analysis of the seepage damage risk of the ice-water accumulation body overburden by integrating multiple test types such as coarse particle physical property test and fine particle grading test, making up for the deficiency of existing research that only targets ordinary rock and soil or a single test type. The control module can accurately set the test parameters according to the test type, ensure the refinement and accuracy of the test process, and improve the reliability of the test results. The data processing module can automatically obtain the test parameters and intermediate parameters, and quickly calculate the target parameters, which greatly reduces the amount of data processing and improves work efficiency. The result analysis module can generate a seepage damage characteristic curve and a performance summary table, providing engineering personnel with intuitive and comprehensive analysis results, which is convenient for quickly identifying and evaluating the risk of seepage damage. At the same time, the disclosed system is specifically designed for the ice-water accumulation body overburden, filling the gap in the analysis of seepage damage risks in this field, and providing strong support for the safe construction of water conservancy and hydropower projects.

[0037] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0039] Figure 1 It is a schematic diagram of the composition of the seepage risk analysis and identification system for the overburden of a deep ice-water accumulation body in the embodiment of the present disclosure.

[0040] Figure 2 It is a fine particle gradation curve diagram in the embodiment of the present disclosure.

[0041] Figure 3 1 is a curve showing the relationship between the disintegration amount of the sample and time at two moisture contents in the embodiments of the present disclosure.

[0042] Figure 4 The figure is a comparison chart of the change in disintegration amount over time of samples with different moisture contents in the soil materials used in the embodiments of the present disclosure and the comparative engineering soil materials.

[0043] Figure 5 The figure is a comparison of the disintegration morphology of samples of soil materials used in the embodiments of the present disclosure and comparative engineering soil materials.

[0044] Figure 6 It is a schematic diagram of the hydraulic gradient loading process in the embodiment of the present disclosure.

[0045] Figure 7 Graph showing the relationship between the permeability coefficient and time t in the embodiment of the present disclosure.

[0046] Figure 8 Graph showing the relationship between the fine particle loss rate and time t in the embodiment of the present disclosure.

[0047] Fig. 9 Graph showing the relationship between volume change and time t in the embodiment of the present disclosure.

[0048] Fig.10 Graph showing the relationship between the permeability coefficient and the hydraulic gradient i in the embodiment of the present disclosure.

[0049] Fig.11 Graph showing the relationship between fine particle loss rate and hydraulic gradient i in the disclosed embodiment.

[0050] Fig.12 Graph showing the relationship between volume change and hydraulic gradient i in the embodiment of the present disclosure.

[0051] Fig.13 Graph showing the relationship between the permeability coefficient and the fine particle loss rate in the embodiment of the present disclosure.

[0052] Fig.14 Graph showing the relationship between volume change and fine particle loss rate in the embodiment of the present disclosure.

[0053] Fig.15 This is a summary table of penetration damage characteristics in the embodiments of the present disclosure.

[0054] Fig.16 It is a curve diagram of the change of flow velocity v with hydraulic gradient i in the embodiment of the present disclosure.

[0055] Fig.17 Graph showing the change of fine particle loss rate μ with hydraulic gradient i in the embodiment of the present disclosure.

[0056] Fig.18 is the volume change ε ​​in the embodiment of the present disclosure v Curve diagram of the change of hydraulic gradient i. DETAILED DESCRIPTION

[0057] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be comprehensive and complete and will fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0058] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0059] The terms "a", "an", "the" and "said" are used to indicate the presence of one or more elements / components / etc.; the terms "comprising" and "having" are used to indicate an open-ended inclusive meaning and mean that additional elements / components / etc. may be present in addition to the listed elements / components / etc.

[0060] With the deepening of western development, the high-altitude areas of the southwest have ushered in a climax of large-scale infrastructure and hydropower projects. In these projects, large-scale glacial deposits often appear as geological background conditions, and their special engineering properties have become an important factor restricting human engineering activities. Glacial deposits, which are sediments formed by the debris carried and transported by glaciers under the action of glacial meltwater, were mostly formed in the Middle and Late Pleistocene of the Quaternary Period. Their engineering properties are closely related to the composition of the parent rock and the filling cement, and they show the characteristics of seasonal freeze-thaw cycles due to climate change in the high-altitude cold areas.

[0061] Due to its special origin, glacial deposits have unique properties such as high non-uniformity coefficient, small effective particle size, and large particle group span, which are significantly different from common Quaternary sediments such as residual deposits, slope deposits, and alluvial deposits. Its main components are glacial deposits containing solitary (blocks) stones and boulders. It is mainly composed of coarse particles, uneven particle composition, wide gradation range, discontinuous distribution, poor sorting, loose surface and dense lower part, and extremely uneven permeability. These characteristics lead to the low shear strength of glacial deposits, relatively poor self-stabilization ability, and the existence of local overhead phenomena, which has brought many difficulties to the construction of water conservancy and hydropower projects. Among them, the problem of seepage damage is particularly prominent, posing a serious threat to project safety.

[0062] In order to comprehensively and in real time record the seepage damage process in the special rock mass such as the ice-water accumulation layer, and to systematically analyze and identify the seepage damage risk, we urgently need a special analysis and identification system.

[0063] Based on this, the present disclosure provides a system for analyzing and identifying the seepage risk of deep ice-water accumulation bodies. Figure 1 As shown, the system includes a test module, a control module, a data processing module and a result analysis module, wherein:

[0064] The test module is used to perform various types of tests on samples of deep ice-water deposits, including coarse particle property test, fine particle grading test, permeability test, disintegration test, permeability damage test and contact scour test of different strata;

[0065] The control module is electrically connected to the test module and is used to set test parameters according to the test type of the test; the test module performs a corresponding type of test on the sample according to the test parameters and records the test results, which include intermediate parameters;

[0066] The data processing module is electrically connected to the test module and the control module, and is used to obtain the test parameters and the intermediate parameters, and calculate the target parameters according to the test parameters and the intermediate parameters;

[0067] The result analysis module is electrically connected to the data processing module and is used to generate a penetration damage characteristic curve and a performance summary table according to the test parameters and target parameters.

[0068] The disclosed deep ice-water accumulation body overburden seepage risk analysis and identification system realizes a comprehensive analysis of the seepage damage risk of the ice-water accumulation body overburden by integrating multiple test types such as coarse particle physical property test and fine particle grading test, making up for the deficiency of existing research that only targets ordinary rock and soil or a single test type. The control module can accurately set the test parameters according to the test type, ensure the refinement and accuracy of the test process, and improve the reliability of the test results. The data processing module can automatically obtain the test parameters and intermediate parameters, and quickly calculate the target parameters, which greatly reduces the amount of data processing and improves work efficiency. The result analysis module can generate a seepage damage characteristic curve and a performance summary table, providing engineering personnel with intuitive and comprehensive analysis results, which is convenient for quickly identifying and evaluating the risk of seepage damage. At the same time, the disclosed system is specifically designed for the ice-water accumulation body overburden, filling the gap in the analysis of seepage damage risks in this field, and providing strong support for the safe construction of water conservancy and hydropower projects.

[0069] The following is a detailed description of each part of the deep ice-water accumulation body cover layer seepage risk analysis and identification system in the embodiment of the present disclosure:

[0070] The test module is an integrated module specially designed for performing various types of tests on samples of deep ice-water deposits, including coarse particle property test, fine particle grading test, permeability test, disintegration test, permeability damage test and contact scour test of different formations. The test module may include an introduction to each type of test, test requirements and related instructions.

[0071] The control module is electrically connected to the test module and is used to set test parameters according to the test type of the test; the test module performs a corresponding type of test on the sample according to the test parameters and records the test results, which include intermediate parameters.

[0072] For example, the control module may include a user interaction interface, which can support the test personnel to operate through a touch screen, a mouse or a keyboard, and then select the corresponding test type, and manually set the test parameters required for the test of this type. In some embodiments of the present disclosure, the test parameters may include one or more of the dry mass, volume, test duration, head difference, overburden pressure, particle size, area, initial height, and initial fine particle mass of the sample. It should be noted that the test parameters input by different types of tests may be completely different or partially the same, and are not specifically limited here. The control module can also set a reminder for the test time to arrive according to the test requirements. The control module can not only connect with the test equipment related to each type of test, set the corresponding test parameters for each test equipment, but also receive and record the manually input parameters (for example, sample dry mass, sample volume, sample area, permeability test water temperature T, variable head pipe cross-sectional area, head at the beginning, sample initial height, etc.), and use the manually input parameters as test parameters.

[0073] In some embodiments of the present disclosure, the intermediate parameters may include one or more of the seepage path length, seepage rate, cross-sectional area of ​​the variable head tube, mass of lost fine particles, and sample sedimentation height corresponding to the head difference. It should be noted that the intermediate parameters obtained from different types of tests may be different or the same, and are not specifically limited here. For example, the intermediate parameters corresponding to the permeability test may include one or more of the seepage path length, seepage rate, mass of lost fine particles, sample sedimentation height, and cross-sectional area of ​​the variable head tube; the intermediate parameters corresponding to the permeability destruction test may include one or more of the seepage path length, seepage rate, mass of lost fine particles, and sample sedimentation height.

[0074] The data processing module is electrically connected to the test module and the control module, and is used to manually or automatically obtain the test parameters and intermediate parameters, and calculate the target parameters based on the test parameters and intermediate parameters, so that the result analysis module can generate the corresponding penetration damage characteristic curve based on the test parameters and target parameters, analyze the penetration damage characteristics of the sample, and generate the corresponding performance summary table. It should be noted that the test parameters manually obtained by the data processing module mainly include some qualitative descriptions or parameters that have been obtained in the early stage or parameters that cannot be directly collected by the system, including but not limited to particle properties, particle diameter, soil moisture content, test instrument size and other data; the automatically collected data is obtained by connecting the system interface to the measuring device of the test equipment, including but not limited to seepage flow, head, time, critical hydraulic gradient, destructive hydraulic gradient, etc.

[0075] The data processing module embeds all calculation formulas involved in various types of tests, and the target parameters can be calculated by the calculation formulas embedded in it. In an exemplary embodiment of the present disclosure, the target parameters may include the dry density, hydraulic gradient, permeability flow rate, permeability coefficient, fine particle loss rate, etc. of the sample. The determination of the target parameters relies on the test parameters and intermediate parameters provided or measured by different types of tests.

[0076] The result analysis module can be electrically connected to the data processing module to generate a penetration damage characteristic curve and a performance summary table based on the test parameters and target parameters. For example, the result analysis module can analyze and organize the above-mentioned test parameters, intermediate parameters and target parameters, and display the sample penetration damage in the form of a relationship curve diagram and a result summary table, and generate a simple text analysis summary, such as what kind of penetration damage will occur in the sample, what is the hydraulic gradient of the damage, etc., so that engineering personnel can analyze and identify the penetration damage risk based on the results. In addition, the result analysis module can also be used to compare and analyze the analysis results with the results of other projects that have been entered into the system, and display a comparison chart or comparison table. The results of each test can be saved in the result analysis module, which is convenient for the next comparative analysis with other test results. As the number of times the system is used increases, a test database can be generated.

[0077] In an exemplary embodiment of the present disclosure, the coarse particle physical property test is mainly for the coarse particles in the ice-water accumulation formation. The coarse particles in the ice-water accumulation formation have a large particle size range and poor particle uniformity. The particles are sharp-edged and not very rounded, and the particles have high strength. Therefore, the skeleton formed by the coarse particles has the characteristics of large porosity and high skeleton strength. That is, the coarse particles in the ice-water accumulation formation have a high non-uniformity coefficient and a large particle group span. The composition, density, morphology, etc. of the coarse particles in the rock mass can be analyzed. For example, when conducting a coarse particle physical property test, the dry mass (m d , unit: g), and measure the volume of the sample (V, unit: cm 3 ), and calculate the dry density (ρ) of the sample based on the dry mass and volume d , unit: g / cm 3 );

[0078] For example, the dry density of a sample can be calculated using the following formula:

[0079]

[0080] It should be noted that since the coarse particle property test is mainly based on on-site measurement and investigation, the test results are qualitative conclusions. The measured dry mass and volume can be manually input into the data processing module, and the dry density can be calculated by the data processing module, that is, the calculation formula corresponding to the dry density is embedded in the data processing module.

[0081] In an exemplary embodiment of the present disclosure, the fine particle gradation test may include measuring the particle gradation in the fine particles by sieve analysis. For example, the sieve analysis method may be used to measure the gradation of particles with a particle size between 0.075 mm and 5 mm in the sample.

[0082] In some embodiments of the present disclosure, measuring the particle size distribution in fine particles by sieving analysis may include steps S110 and S120, wherein:

[0083] Step S110, using a plurality of sieves with different apertures to sequentially sieve the sample in descending order of aperture. For example, sieves with apertures of 5 mm, 2 mm, 1 mm, 0.5 mm, 0.25 mm, and 0.075 mm may be selected. These sieves may be arranged from top to bottom in descending order of aperture, so as to perform screening in sequence.

[0084] Step S120, weighing the mass of the particles remaining on each sieve after sieving. For example, a balance may be used to weigh the mass of the particles remaining on each sieve.

[0085] It should be noted that since the fine particle gradation test is measured using a simple sieve analysis method, it is impossible to access the system interface of the data processing module to achieve automatic data collection. Therefore, the sample gradation information can be manually entered in the data processing module.

[0086] In the result analysis module, you can set the mass percentage of samples smaller than a certain particle size as the ordinate and the particle diameter as the abscissa, and draw a particle size distribution graph on the single logarithmic abscissa. Finally, in the data analysis and display module, you can get a fine particle gradation curve (such as Figure 2 As shown in the table) and the corresponding parameter table. Figure 2 It can be seen that the distribution of coarse and fine particles in the glacial water accumulation strata is extremely uneven, and the fine particles are cemented between the suspended coarse-grained skeletons. The compacted soil blocks of the fine-grained part have a small permeability coefficient, but after the compacted cemented soil blocks are soaked in water, the particles are quickly peeled off from the free surface in a loose state, indicating that the water stability of the fine-grained part of the on-site cementation is poor and it is easy to be eroded by pore water flow in the presence of a free surface.

[0087] In an exemplary embodiment of the present disclosure, the permeability test may use a variable head permeameter to measure the permeability coefficient of the sample. In the present disclosure, the size of the permeameter may be 30 cm 2 ×4cm. For example, the penetration test may include steps S210 to S240, wherein:

[0088] Step S2410, loading the sample into a sample tube of the permeameter, connecting the water head controller of the permeameter to the control module, and setting the water head of the permeameter through the control module.

[0089] The sample tube can be cleaned first to ensure that it is clean and free of impurities. Place a layer of permeable stone or filter paper at the bottom of the sample tube to ensure that water can flow evenly through the sample. Load the pre-treated sample (such as dried, sieved and mixed) into the sample tube, and ensure that the sample is filled evenly and densely to avoid bubbles or gaps during the filling process, so as not to affect the accuracy of the test results. Place a layer of permeable stone or filter paper on the top of the sample to cover the entire sample surface, and ensure that the permeable stone or filter paper is in close contact with the inner wall of the sample tube to prevent water from seeping out from the sides.

[0090] In some embodiments of the present disclosure, the water head controller of the permeameter can be connected to the control module through a cable or a data line, and the height of the water head can be accurately controlled by the control module. For example, the initial water head height of the permeameter is set by the control module, and the appropriate water head range is determined according to the test requirements to ensure that the water head setting is accurate and stable, so that the water head change can be accurately measured during the test.

[0091] Step S220: slowly inject water into the bottom to fully saturate the sample and exhaust the air.

[0092] The water injection system of the permeameter can be turned on to allow water to flow slowly from the bottom of the sample tube. Control the water injection rate to ensure that the water can penetrate the sample evenly and slowly to avoid shock or disturbance. Closely observe the wetness of the sample surface and the discharge of bubbles. When the sample surface is completely wet and no more bubbles are discharged, the sample is considered to be fully saturated. After the sample is saturated, continue to keep the water injection system open for a period of time to ensure that the water content inside the sample is evenly distributed.

[0093] Step S230, recording the initial water head height.

[0094] The initial water head position can be recorded manually, or a camera device can be set up to record the initial water head height by taking photos or videos.

[0095] Step S240, open the water outlet and record the water head height every 30 minutes.

[0096] After recording the initial height, the outlet can be opened and the changes in water head can be recorded at different time points. For example, the water head change can be recorded every 30 minutes, and this can be measured three times in a row. Then the water head is raised to the preset height (for example, the initial water head position), and the water head position is recorded six times in a row.

[0097] In some embodiments of the present disclosure, the hydraulic gradient can be controlled by controlling the head difference of the pressure measuring tube and the seepage path length corresponding to the head difference. For example, the hydraulic gradient can be calculated by the following formula 2:

[0098]

[0099] Where i is the hydraulic gradient; ΔH is the head difference of the pressure tube, in cm; L is the seepage path length corresponding to the head difference ΔH, in cm.

[0100] It should be noted that the pressure tube head difference ΔH and the seepage path length L corresponding to the head difference can be obtained by manual measurement, and the above calculation process can be executed by the data processing module, that is, the calculation formula corresponding to the hydraulic gradient is embedded in the data processing module.

[0101] During the permeation test, the permeation flow rate and sample area of ​​the sample can also be measured, and the permeation flow rate can be calculated by the permeation flow rate and sample area. For example, the permeation flow rate can be calculated by the following formula 3:

[0102]

[0103] Where Q is the seepage rate, in cm 3 / s; A is the sample area, unit is cm 2 ; v is the permeability flow rate, unit is cm / s.

[0104] The permeability coefficient of the sample can also be calculated based on the permeability flow rate and hydraulic gradient. For example, the permeability coefficient can be calculated using the following formula 4:

[0105]

[0106] Among them, v is the infiltration velocity; i is the hydraulic gradient; k is the permeability coefficient.

[0107] During the variable head permeability test, the calculation formula of the permeability coefficient is shown in Formula 5 below:

[0108]

[0109] Among them, k T is the permeability coefficient of the sample at water temperature T℃, in cm / s; a is the cross-sectional area of ​​the variable head pipe, in cm 2 ; L is the seepage diameter, in cm / s, which is generally equal to the sample height; A is the sample area, in cm 2 ;H b1 is the water head at the beginning, in cm / s; H b2 is the water head at the end, in cm / s; t is the test duration.

[0110] In an exemplary embodiment of the present disclosure, the disintegration test may include steps S310 to S320, wherein:

[0111] Step S310, placing the sample in a soaking container and allowing water to submerge the sample.

[0112] Place the pre-treated sample (e.g., cut into appropriate size, remove surface impurities) into the immersion container, and ensure that the sample is placed stably to avoid movement or tilting during the immersion process. Use clean tap water or deionized water to slowly pour into the immersion container until the water surface completely submerges the sample. Pay attention to the speed of adding water to avoid water flow impacting the sample and causing premature disintegration. Determine the immersion time according to the test requirements. Usually, it is long enough for the sample to fully absorb water and reach a saturated state. During the immersion period, the water temperature can be kept constant to eliminate the influence of temperature on the disintegration process.

[0113] Step S320, using a disintegrator to perform rotational disintegration on the soaked sample.

[0114] Take the soaked sample out of the container and place it on the rotating disk of the disintegration instrument. Make sure the sample is firmly fixed to avoid falling off or flying out during the rotation. Start the disintegration instrument and let the rotating disk start to rotate.

[0115] In some embodiments of the present disclosure, the infiltration risk analysis and identification system further includes a camera device, which is used to take photos or videos at preset time intervals to record the amount of disintegration at different time points.

[0116] For example, a camera device, such as a high-definition camera or video camera, can be installed near the disintegration instrument. Ensure that the position and angle of the camera device can clearly capture the disintegration process of the sample. The camera device can be electrically connected to the control module, and the control module can be used to set the photo or video recording time and time interval of the camera device according to the test requirements to ensure that the quality of the photo or video is high enough for subsequent accurate analysis of the disintegration amount.

[0117] In some embodiments of the present disclosure, a disintegration test can be performed on samples with different moisture contents (for example, moisture contents ω=0 and ω=10%), a camera or camera connection system is set up in front of the disintegration test, and a video and photo of the entire test process is taken and uploaded to the system, and the test ends when the sample does not disintegrate for a long time and is stable or completely disintegrated. In an exemplary embodiment of the present disclosure, the data processing module can be electrically connected to the camera device, and during the test, the camera device can transmit the test start time, photo or video shooting time, duration, and disintegration amount back to the data processing module in real time, and the data processing module can record the test start time in real time and record the sample disintegration amount every 1 minute.

[0118] In the result analysis module, the relationship curve of sample disintegration amount over time can be plotted with time as the horizontal axis and disintegration amount as the vertical axis. The video and photos taken can be used for subsequent data review and comparison with other tests. Finally, in the result analysis module, a curve of the relationship between sample disintegration amount and time under different moisture contents can be obtained (such as Figure 3In addition, in the present disclosure, the disintegration test process diagram and results of another engineering soil sample are uploaded in the result analysis module, and comparative analysis and display are performed in the result analysis module ( Figure 4 and Figure 5 shown), through Figure 4 and Figure 5 It can be seen that the disintegration morphology of the samples in this test is granular or small loose particles, while the disintegration morphology of the samples in another project is large fragments.

[0119] In an exemplary embodiment of the present disclosure, a permeability damage test can also be performed on the sample. The forms of permeability damage are divided into two forms: piping and soil flow. Piping refers to the damage form in which fine particles are gradually lost with the seepage, and soil flow refers to the damage form in which the soil body flows as a whole. Whether the permeability damage form is piping or soil flow can be determined based on the photos or videos taken by the camera. For the two damage forms, their critical hydraulic gradient i K and damage hydraulic gradient i F The result analysis module can use the hydraulic gradient i as the horizontal coordinate and the seepage velocity v as the vertical coordinate to draw a curve of the relationship between the seepage velocity and the hydraulic gradient (iv curve), which can be completed by the result analysis module.

[0120] According to the IV curve, the critical hydraulic gradient i k It can be determined by the following method: When the slope of the IV relationship curve begins to change and fine particles are observed to start jumping or being carried out by the water flow, the sample is considered to have reached the critical hydraulic gradient i k , critical hydraulic gradient i k It can be determined by the following formula 6:

[0121]

[0122] Among them, i2 is the hydraulic gradient when piping begins to occur; i1 is the hydraulic gradient one level before piping begins to occur.

[0123] As the water head gradually increases, fine particles are continuously washed away, and the infiltration flow rate increases. When the water head increases to the point where the sample loses its anti-seepage strength, the hydraulic gradient at this time is called the sample's destructive hydraulic gradient i F , the hydraulic gradient can be determined by the following formula 7:

[0124]

[0125] Among them, i′2 is the hydraulic gradient of seepage when the sample is destroyed; i′1 is the hydraulic gradient before the beginning of piping.

[0126] It should be noted that when soil flow failure occurs, sometimes i′2 is not easy to measure, then the failure hydraulic gradient can be determined according to the following formula 8:

[0127] i F =i′1 Formula 8.

[0128] In an exemplary embodiment of the present disclosure, a permeability damage test may be performed under given hydraulic gradient conditions. For example, the form of permeability damage of a sample under pressure conditions and the critical hydraulic gradient of permeability damage may be determined under conditions of gradually increasing hydraulic gradients.

[0129] In some embodiments of the present disclosure, the penetration damage test may include steps S410 to S430, wherein:

[0130] Step S410, adjusting the particle size distribution of the sample according to the test range of the permeameter, so that the particle size distribution of the sample meets the test range of the permeameter.

[0131] Since there are oversized particles (i.e., particle size > 60mm) in the in-situ grading of the sample that exceed the test range of the permeameter, in order to avoid size effects in the test, the original grading needs to be adjusted. For example, the elimination method, skeleton replacement method, translational scaling method, intermittent elimination method, or lower envelope method can be used to adjust the particle grading of the sample. Specifically, the elimination method grading is to remove soil particles with a particle size greater than 60mm in the soil to study the penetration damage characteristics of components below 60mm under the original grading; the skeleton replacement grading is to replace particles greater than 40mm with particles of 40mm to 60mm, adapting to the permeameter while ensuring that the grading less than 40mm in the test grading is consistent with the original grading; the translational scaling grading is to reduce the size of the soil according to a certain ratio so that the grading adapts to the maximum particle size of 60mm allowed by the permeameter, and the translational scaling grading retains the original grading curve. The relative size relationship between each particle group in the soil can better simulate the internal stability of the original graded soil; the discontinuous grading is based on the translation scaled grading, and the particle size of 5mm to 40mm is eliminated to artificially create a discontinuous grading curve to simulate the extreme conditions that may exist on site; the lower envelope grading is the lower envelope of multiple original grading curves. The grading is adapted to the maximum particle size of 60mm allowed by the permeameter through the elimination method. Since the fine particle content of this grading is lower than that of the original grading, it can reflect the permeability characteristics of the original grading with poor permeability stability. Engineers can choose the corresponding grading adjustment method according to the characteristics of the test soil sample and the test needs.

[0132] Step S420, performing a permeability failure test on the sample after adjusting the particle gradation, and simulating the permeability behavior under different working conditions by controlling the hydraulic gradient and the overburden pressure.

[0133] The hydraulic gradient control, pressure loading device and collection and measurement device of the penetration compression tester can be connected to the system interface of the control module, and the step hydraulic gradient loading (loading process such as Figure 6), set the overburden pressure loading, set the system to record the test data every 30 minutes; automatically collect and record the test time, hydraulic gradient, seepage, loss of fine particles, sample settlement height and other parameters in the data processing module, and use the formula in the data processing module to calculate the permeability coefficient, fine particle loss rate, volume change and other parameters. And set and select different parameter groups to analyze the relationship between the changes in parameters.

[0134] For example, the fine particle loss rate can be calculated by the following formula 9:

[0135]

[0136] Among them, m f is the mass of fine particles lost, in g; m f0 is the initial fine particle mass in the sample, in g; μ is the fine particle loss rate.

[0137] The volume change of the sample can be calculated by the following formula:

[0138]

[0139] Where, Δh is the sample sedimentation; h0 is the initial height of the sample; ε v For body change.

[0140] Step S430, recording the test time, the hydraulic gradient, the seepage rate, the mass of the lost fine particles and the sample settling height through the control module.

[0141] The test time, hydraulic gradient, seepage rate, mass of lost fine particles, and sample settling height recorded by the control module can be transmitted to the data processing module, which can be used to calculate the parameters. After the data processing module calculates the parameters, a graph of the change in permeability coefficient over time t can be generated in the result analysis module (e.g. Figure 7 As shown in the figure), the relationship between the fine particle loss rate and time t (as shown in the figure Figure 8 As shown in the figure), the relationship between body change and time t (as shown in the figure) Fig. 9 As shown in the figure), the relationship between the permeability coefficient and the hydraulic gradient i (as shown in the figure Fig.10 As shown in the figure), the relationship between the fine particle loss rate and the hydraulic gradient i (as shown in the figure Fig.11 As shown in the figure), the relationship between volume change and hydraulic gradient i (as shown in the figure Fig.12 As shown in the figure), the relationship between the permeability coefficient and the fine particle loss rate (as shown in the figure Fig.13 As shown in the figure), the relationship between volume change and fine particle loss rate (as shown in the figure Fig.14 At the same time, a summary table of penetration damage characteristics is generated (as shown in Fig.15 ). Figure 7-Figure 15It can be seen that the upper ice-water accumulation stratum is internally stable soil in the area where fine particles are completely filled (see elimination method gradation); in the area where coarse particles are empty (see skeleton replacement gradation and discontinuous gradation), due to the small content of fine particles or discontinuous grading, when the hydraulic gradient exceeds the range of 0.1 to 0.2, significant fine particle (<2mm particle) loss (loss rate reaches 50%) can occur, and cause a significant change in the permeability coefficient (reaching the order of 5 to 10 cm / s), which is a typical internal unstable soil. Considering the disintegration characteristics of fine particles and the penetration damage test results of samples with different gradings, the upper ice-water accumulation stratum has the risk of penetration damage, and it is recommended that the critical hydraulic gradient for ice-water accumulation stratum to induce fine particle loss be determined as i k =0.1, the critical flow velocity is determined to be 0.1cm / s; the fine particle content of the lower sandy gravel stratum is between 20% and 35%, the gradation is relatively continuous, the fine particles are completely filled in the coarse particle skeleton, and there is no obvious loss of fine particles under the high overburden pressure of the test (2-2.8MPa). It can be considered that the sandy gravel layer deep in the overburden of the ice-water accumulation body is an internal stable soil layer, and there is no risk of seepage damage.

[0142] In an exemplary embodiment of the present disclosure, the permeability of the upper soil layer of the ice-water accumulation body cover layer is better than that of the lower layer, so it is easy to cause contact scour damage to the lower layer at the interlayer contact surface. It is necessary to conduct contact scour tests on different strata. For example, the critical hydraulic gradient and destructive hydraulic gradient for contact scour of a double-layer foundation, as well as the critical flow rate and destructive flow rate can be given. For example, the hydraulic gradient control and collection measurement device of the penetration compression tester can be connected to the system interface of the control module in the present disclosure, and a step hydraulic gradient loading (loading process such as Figure 6 ), set the established overburden pressure loading, set the system to record the test data every 30 minutes; automatically collect and record the test time, flow rate, sand influx and other parameters in the data processing module. And set and select different parameter groups to analyze the relationship between the parameters.

[0143] In some embodiments of the present disclosure, a camera device can be installed in front of the contact scour test in different formations, and the entire test process can be videoed and photographed by the camera device and uploaded to the data processing module and / or the result analysis module. Finally, a curve diagram of the change of flow velocity v with hydraulic gradient i can be generated in the result analysis module (e.g. Fig.16 As shown in the figure), the fine particle loss rate μ changes with the hydraulic gradient i (as shown in the figure Fig.17 shown), body change ε v The curve diagram of the change of hydraulic gradient i (such as Fig.18 ). Figure 15-18It can be seen that the ice-water deposits on the upper part of the deep ice-water deposit cover have less fine-grained content and higher permeability coefficient, while the sand and gravel layer on the lower part has higher fine-grained content and lower permeability coefficient. The test results show that the double-layer foundation model will undergo contact scouring damage, but the degree of damage is limited. It is recommended that the critical flow velocity for contact scouring be determined as 0.2 cm / s.

[0144] The present invention can comprehensively, precisely, automatically and conveniently realize the risk analysis and identification of seepage damage to the covering layer of deep ice-water accumulation bodies, determine the possibility and form of seepage damage, and give the critical conditions for the occurrence of seepage damage, provide parameters and data support for subsequent three-dimensional calculations and other work, and provide a reliable basis for engineering personnel to carry out early warning measures and preventive measures for seepage damage to the covering layer of deep ice-water accumulation bodies.

[0145] In an exemplary embodiment of the present disclosure, the penetration risk analysis and identification system of the present disclosure may also include a storage device, which is electrically connected to the data processing module and the result analysis module, and is used to store test parameters, intermediate parameters, target parameters, calculation formulas in the calculation process, and pictures and videos acquired by the camera device. The acquisition of photo or video data can be achieved by manual uploading and automatic shooting. Manual uploading is to upload the acquired photos and videos to the corresponding folder in the storage device; automatic shooting refers to setting up a camera device in front of the test instrument, connecting the camera device to the storage device and the control module wirelessly or wired, and the control module can set the start, end and interval of the camera device. At the same time, the photos and videos taken by the camera device can be transmitted and stored in the corresponding folder of the storage device in real time. The engineering personnel can set the corresponding folder name and storage path before the start of the test.

[0146] In an exemplary embodiment of the present disclosure, the infiltration risk analysis and identification system of the present disclosure may further include a display component, which may include a display, and the display may display the infiltration damage characteristic curve and the performance summary table. That is, the display may be used to visualize whether the sample will undergo infiltration damage, what form of infiltration damage will occur, and the critical conditions for the occurrence.

[0147] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A system for analyzing and identifying the seepage risk of deep ice-water accumulation layers, characterized in that: include: A test module for performing various types of tests on samples of deep ice-water deposits, including coarse particle property tests, fine particle grading tests, permeability tests, disintegration tests, permeability damage tests, and contact scour tests of different strata; A control module, electrically connected to the test module, for setting test parameters according to the test type of the test; the test module performs a corresponding type of test on the sample according to the test parameters, and records the test results, which include intermediate parameters; a data processing module, electrically connected to the test module and the control module, and configured to obtain the test parameters and the intermediate parameters, and calculate the target parameters according to the test parameters and the intermediate parameters; The result analysis module is electrically connected to the data processing module and is used to generate a penetration damage characteristic curve and a performance summary table according to the test parameters and the target parameters.

2. The penetration risk analysis and identification system according to claim 1, characterized in that: The test parameters include one or more of the dry mass, volume, test time, head difference, overburden pressure, particle size, area, initial height, and initial fine particle mass of the sample; the intermediate parameters include one or more of the seepage path length corresponding to the head difference, seepage flow, variable head pipe cross-sectional area, lost fine particle mass, and sample sedimentation height; the target parameters include the dry density, hydraulic gradient, infiltration flow rate, permeability coefficient, and fine particle loss rate of the sample.

3. The penetration risk analysis and identification system according to claim 1, characterized in that: The fine particle gradation test includes: The particle size distribution in the fine particles is measured by sieve analysis.

4. The penetration risk analysis and identification system according to claim 3, characterized in that: The method of measuring the particle size distribution in the fine particles by sieve analysis includes: Using a plurality of sieves with different apertures, sifting the sample in order from large to small apertures; After sieving, weigh the mass of the particles remaining on each sieve.

5. The penetration risk analysis and identification system according to claim 1, characterized in that: The penetration test includes: The sample is loaded into a sample tube of the permeameter, a water head controller of the permeameter is connected to the control module, and the water head of the permeameter is set by the control module; Slowly add water from the bottom to fully saturate the sample and expel air; Record the initial water head height; Open the water outlet and record the water head height every 30 minutes.

6. The penetration risk analysis and identification system according to claim 1, characterized in that: The disintegration test includes: placing the sample in an immersion container and allowing water to submerge the sample; Using a disintegrator to perform rotational disintegration on the soaked sample; The infiltration risk analysis and identification system also includes a camera device, which is used to take photos or videos at preset time intervals to record the disintegration amount at different time points.

7. The penetration risk analysis and identification system according to claim 2, characterized in that: The penetration damage test includes: Adjusting the particle size distribution of the sample according to the test range of the permeameter so that the particle size distribution of the sample conforms to the test range of the permeameter; Conducting a permeability failure test on the sample after adjusting the particle gradation, and simulating the permeability behavior under different working conditions by controlling the hydraulic gradient and the overburden pressure; The test time, the hydraulic gradient, the seepage rate, the mass of the lost fine particles and the sample settling height are recorded by the control module.

8. The penetration risk analysis and identification system according to claim 7, characterized in that: The step of adjusting the particle size distribution of the sample according to the test range of the permeameter comprises: The particle size distribution of the sample is adjusted by using elimination method, skeleton replacement method, translation reduction method, discontinuous elimination method or lower envelope method.

9. The penetration risk analysis and identification system according to claim 6, characterized in that: The penetration risk analysis and identification system also includes: A storage device is electrically connected to the data processing module and the result analysis module, and is used to store the test parameters, the intermediate parameters, the target parameters, the calculation formulas in the calculation process, and the pictures and videos obtained by the camera device.

10. The penetration risk analysis and identification system according to claim 1, characterized in that: The system further comprises: The display component includes a display capable of displaying the penetration damage characteristic curve and the performance summary table.

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