Lossless moisture content testing device for self-weight deposition of sludge

Abstract

The utility model discloses a lossless moisture content testing device for self-weight deposition of sludge. The lossless moisture content testing device comprises a deposition assembly, a drainage assembly, a shell and a testing assembly, the sedimentation column is used for simulating the self-weight deposition process of the high-water-content dredged mud, and the coaxial cable detector is used for measuring the water content of The coaxial cable detector can quickly and nondestructively measure the moisture content change of the sludge at different heights in the self-weight deposition process, and can be used for quickly and quantitatively analyzing the humidity distribution condition of the sludge in the self-weight deposition process in engineering. A shell is arranged on the outer side of a settlement column, probe sets are installed on the periphery, the upper portion and the lower portion of the settlement column at intervals, it is ensured that a waveguide rod is exactly in contact with the settlement column, and the electromagnetic waves received by coaxial cable detectors of different heights are transmitted to soil in the settlement column according to the difference of time needed by the soil in the settlement column. A relation curve between the feedback time of the electromagnetic waves and the water content is obtained, and the water content of slurry at different heights can be rapidly calibrated.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of geotechnical engineering basic test, especially relate to a kind of nondestructive water content testing device for silt self-weight deposition. BACKGROUND

[0002] 2023 China's total dredging engineering reaches 10.89 million cubic meters, dredging mud has the characteristics of high water content, low strength and large deformation, usually uses the high water content dredging mud pumped into cofferdam yard by screw suction type equipment to be disposed. Silt in yard will occur self-weight deposition, different size clay particles sink at different speeds, particle sorting effect appears, vertical section silt water content changes with time. How to determine silt water content changes with time in self-weight deposition process is crucial for calculating self-weight deposition rate and stabilization time in actual engineering.

[0003] Traditional test tube extracts silt at different depths to determine water content, but sampling process greatly disturbs silt particles in settling column, artificially affects silt particle self-weight deposition, changes silt particle gradation, and cannot real-time high-frequency monitor silt particle deposition process, silt water content distribution error obtained by determination is extremely large. SUMMARY

[0004] Therefore, the utility model aims at providing a kind of nondestructive water content testing device for silt self-weight deposition.

[0005] To achieve the above technical purpose, the utility model adopts the technical scheme that:

[0006] The application provides a nondestructive water content testing device for silt self-weight deposition, which comprises a deposition assembly, a drainage assembly, a shell and a testing assembly. The deposition assembly comprises a settling column, a base and a cover plate. The settling column is arranged on the base in the vertical direction. The cover plate is arranged on the top of the settling column. The settling column is provided with a scale line on the outside. The settling column is provided with a soil formed by silt. The drainage assembly comprises a first drainage pipe group and a second drainage pipe group. The first drainage pipe group comprises a plurality of first drainage pipes. The plurality of first drainage pipes are arranged in the axial direction of the settling column in a spaced manner from top to bottom. Each first drainage pipe is in communication with the settling column. The second drainage pipe group comprises at least one second drainage pipe. The second drainage pipe is in communication with the settling column through the base. The shell is arranged on the periphery of the settling column. The testing assembly is arranged on the shell. The number of the testing assembly is a plurality. The testing assembly is arranged in a spaced manner in the axial direction of the shell from top to bottom. Each testing assembly comprises a plurality of probe groups. The plurality of probe groups of the same testing assembly are arranged in a spaced manner in the circumferential direction of the settling column. Each probe group comprises a coaxial cable detector and at least one waveguide rod. The waveguide rod is arranged on the shell. The end of the waveguide rod is in abutment with the outside of the settling column. The coaxial cable detector is connected with the waveguide rod. The coaxial cable detector is used for emitting electromagnetic waves to the soil in the settling column and receiving electromagnetic waves of the soil in the settling column.

[0007] In some embodiments, the deposition assembly further comprises a plurality of sleeves. The plurality of sleeves are detachably connected by fasteners from top to bottom. Two adjacent sleeves are airtight connected to form the settling column. At least one first drainage pipe is arranged on each sleeve. At least one testing assembly is arranged on each sleeve.

[0008] In some embodiments, the deposition assembly further comprises a first filter layer, a geotextile, a water-permeable plate and a second filter layer. The first filter layer is arranged on the base. The first filter layer is configured as filter paper wetted with distilled water. The geotextile is arranged on the first filter layer. The water-permeable plate is arranged on the geotextile. The water-permeable plate is matched with the settling column. The second filter layer is arranged on the water-permeable plate. The second filter layer is configured as filter paper wetted with distilled water.

[0009] In some embodiments, the deposition assembly further comprises a second sealing ring and a plurality of first sealing rings. The number of the first sealing rings corresponds to the number of the sleeves. One first sealing ring is arranged between two adjacent sleeves. The second sealing ring is arranged at the connection between the settling column and the base.

[0010] In some embodiments, the material of the sleeve is acrylic plate. The material of the base is hard polyvinyl chloride. The material of the water-permeable plate is hard polyvinyl chloride. The first sealing ring and / or the second sealing ring is O-shaped sealing ring. The material of the cover plate is acrylic plate. The material of the shell is acrylic plate.

[0011] In some embodiments, the diameter of the sleeve is 200 mm, the height of the sleeve is 200 mm, and the wall thickness of the sleeve is 10 mm; and / or, the diameter of the first sealing ring is 180 mm; and / or, the diameter of the second sealing ring is 180 mm; and / or, the diameter of the base is 240 mm, and the height of the base is 20 mm; and / or, the diameter of the water permeable plate is 180 mm, and the water permeable plate is circular.

[0012] In some embodiments, the deposition assembly further comprises an electronic scale arranged below the base, the electronic scale being configured to detect the weight of the soil in the sedimentation column.

[0013] In some embodiments, the coaxial cable detector comprises an electromagnetic wave generator configured to generate a square high-frequency electromagnetic wave signal, and an oscilloscope configured to analyze the feedback time of the square high-frequency electromagnetic wave signal.

[0014] In some embodiments, the probe set further comprises an insulating handle, and a plurality of waveguide rods are arranged on the insulating handle, and the coaxial cable detector is connected to the plurality of waveguide rods through the insulating handle.

[0015] In some embodiments, the base is provided with a connecting hole, one end of the connecting hole is in communication with the inside of the sedimentation column, and the other end of the connecting hole is in communication with the second drain pipe, and the testing device further comprises a control valve arranged on the second drain pipe.

[0016] Compared with the prior art, the technical scheme has the beneficial effects that:

[0017] Compared with the prior art, the technical scheme has the beneficial effects that: BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0019] Figure 1 is the first schematic diagram of the testing device;

[0020] Figure 2 is the second schematic diagram of the testing device;

[0021] Figure 3 is the third schematic diagram of the testing device;

[0022] Figure 4 is the schematic diagram of the probe group.

[0023] Reference signs:

[0024] 1, deposition assembly;

[0025] 11, settling column;

[0026] 111, sleeve;

[0027] 12, base;

[0028] 121, connecting hole;

[0029] 13, cover plate;

[0030] 14, water-permeable plate;

[0031] 15, first sealing ring;

[0032] 16, electronic scale;

[0033] 2, drainage assembly;

[0034] 21, first drainage pipe;

[0035] 22, second drainage pipe;

[0036] 3, shell;

[0037] 4, testing assembly;

[0038] 41, coaxial cable detector;

[0039] 42, waveguide rod;

[0040] 43, insulating handle;

[0041] 5, control valve. DETAILED DESCRIPTION

[0042] The utility model will be described in further detail below in conjunction with the drawings and embodiments. It is particularly pointed out that the following embodiments are only used for illustrating the utility model, but do not limit the scope of the utility model. Similarly, the following embodiments are only part of the embodiments of the utility model rather than all the embodiments, and all other embodiments obtained by the ordinary skilled in the art without creative labor belong to the scope of protection of the utility model.

[0043] Please refer to Figures 1 to 4 The embodiment provides a kind of for silt self-weight deposition nondestructive water content testing device, including deposition component 1, drainage component 2, shell 3 and test component 4, deposition component 1 includes settling column 11, base 12, cover plate 13, settling column 11 is set on base 12 along vertical direction, cover plate 13 is covered in the top of settling column 11, the outside of settling column 11 is equipped with scale line, and soil body formed by silt is equipped in settling column 11;Drainage component 2 includes first drainage pipe 21 group and second drainage pipe 22 group, first drainage pipe 21 group includes multiple first drainage pipe 21, multiple first drainage pipe 21 is spaced distribution from top to bottom along the axial direction of settling column 11, and every first drainage pipe 21 is communicated with settling column 11, second drainage pipe 22 group includes at least one second drainage pipe 22, and second drainage pipe 22 is communicated with settling column 11 by base 12;Shell 3 is covered in the periphery of settling column 11;Test component 4 is set on shell 3, the quantity of test component 4 is multiple, and is spaced distribution from top to bottom along the axial direction of shell 3, every test component 4 includes multiple probe group, and multiple probe groups of same test component 4 are spaced distribution along the circumferential direction of settling column 11;Every probe group includes coaxial cable detector 41 and at least one waveguide rod 42, waveguide rod 42 is set on shell 3, and the end of waveguide rod 42 is in abutment with the outside of settling column 11, coaxial cable detector 41 is connected with waveguide rod 42, and coaxial cable detector 41 is used to emit electromagnetic wave to the soil body in settling column 11 and receive the electromagnetic wave of the soil body in settling column 11.

[0044] In the embodiment, settling column 11 can be understood as the main structure for installing silt, and the settling column 11 is a hollow cylinder with open ends. Optionally, the settling column 11 can be made of transparent acrylic plate. A cover plate 13 is provided above the settling column 11, which can be opened when silt needs to be installed. A base 12 is provided below the settling column 11, which can be connected to the second drainage pipe 22 to adjust the water level in the settling column 11. Further, the outside of the settling column 11 can be attached to a paperboard with scale lines, a plastic sticker with scale lines, etc. This way, the height of the soil in the settling column 11 can be directly checked through the settling column 11.

[0045] Furthermore, the drainage assembly 2 includes a first drainage pipe group 21 and a second drainage pipe group 22. The first drainage pipe group 21 includes multiple first drainage pipes 21, which are spaced apart along the vertical direction of the settling column 11. The arrangement of the first drainage pipes 21 facilitates the adjustment of the liquid content at different heights. The second drainage pipe group 22 includes at least one second drainage pipe 22. That is, the number of second drainage pipes 22 can be one or more. The second drainage pipes 22 are arranged in the circumferential direction of the base 12. The second drainage pipes 22 are connected to the settling column 11 through the connection hole 121 in the base 12. The second drainage pipes 22 can drain the water in the settling column 11. Similarly, the arrangement of the second drainage pipes 22 facilitates the adjustment of the liquid content in the settling column 11 according to actual needs during the test.

[0046] In this embodiment, a housing 3 is fitted over the settlement column 11. The housing 3 can be made of the same material as the settlement column 11, i.e., a transparent acrylic sheet. The housing 3 is provided to facilitate the fixing of the test components 4. Specifically, there are multiple test components 4, which are distributed along the vertical direction of the settlement column 11. Furthermore, each test component 4 includes multiple probe groups, which are distributed along the circumference of the settlement column 11, such as... Figure 2 and Figure 3 As shown, each probe group includes a coaxial cable detector 41 and a waveguide rod 42. The number of waveguide rods 42 can be set according to actual needs. The coaxial cable detector 41 is connected to the waveguide rod 42. Specifically, the coaxial cable detector 41 can emit electromagnetic waves. When the emitting end of the coaxial cable detector 41 is connected to the waveguide rod 42, the waveguide rod 42 can act as a medium for the electromagnetic waves. Since the waveguide rod 42 abuts against the outside of the settlement column 11, the electromagnetic waves can be directly transmitted to the soil inside the settlement column 11 through the waveguide rod 42. The specific principle is described in detail later. The soil will reflect the electromagnetic waves. Furthermore, the coaxial cable detector 41 also has the function of receiving electromagnetic waves reflected by the soil. That is, the coaxial cable detector 41 also has a receiving end, which is also connected to the waveguide rod 42. The reflected electromagnetic waves can return to the coaxial cable detector 41 through the waveguide rod 42. By detecting the reflection time difference of the electromagnetic waves, further research on the moisture content can be carried out. See the following description for details.

[0047] This embodiment achieves soil moisture content testing at multiple locations within the settlement column 11 by setting multiple test components 4 around the settlement column 11. This process does not require sampling of the soil inside the settlement column 11, thus achieving non-destructive testing and improving testing efficiency.

[0048] Please see Figure 2In some embodiments, the deposition assembly 1 further includes a plurality of sleeves 111, which are detachably connected from top to bottom by fasteners, and two adjacent sleeves 111 are airtightly connected to form a sedimentation column 11. Each sleeve 111 is provided with at least one first drain pipe 21 and at least one test assembly 4.

[0049] In this embodiment, the settlement column 11 is divided into multiple sleeves 111. The multiple sleeves 111 can have identical structural dimensions, and the multiple sleeves 111 can be detachably connected to each other by fasteners. For example... Figure 2 An example of two adjacent sleeves 111 connected by bolts is shown. Optionally, five sleeves 111 are used to facilitate the handling and use of the settlement column 11. Each sleeve 111 may be equipped with multiple test components 4. Optionally, each sleeve 111 is equipped with at least one first drainage pipe 21 to facilitate the adjustment of the liquid water content in each sleeve 111 according to actual needs. It should be noted that two adjacent sleeves 111 are interconnected, thus forming a complete settlement column 11. The adjustment of the water content in each sleeve 111 by the first drainage pipe 21 can be understood as the first drainage pipe 21 being able to adjust the water content of the soil at different heights.

[0050] This embodiment, by dividing the settling column 11 into multiple sleeves 111, better meets the actual needs of transporting the test device in sludge settling tests, making the use of the settling column 11 more convenient.

[0051] Please see Figure 2 In some embodiments, the deposition assembly 1 further includes a first filter layer, a geotextile, a permeable plate 14, and a second filter layer. The first filter layer is disposed on the base 12 and is configured as filter paper wetted with distilled water. The geotextile is disposed on the first filter layer. The permeable plate 14 is disposed on the geotextile and is adapted to the sedimentation column 11. The second filter layer is disposed on the permeable plate 14 and is configured as filter paper wetted with distilled water.

[0052] In this embodiment, the materials and structures of the first filter layer and the second filter layer can be exactly the same. The difference lies in the different positions of the first filter layer and the second filter layer. A permeable plate 14 and a geotextile are also provided between the first filter layer and the second filter layer. Specifically, the geotextile is a permeable geosynthetic material made of synthetic fibers through needle punching or weaving. The geotextile is also used for filtration. The permeable plate 14 has multiple small pores, which can block the passage of silt while draining water, effectively preventing the loss of soil particles and ensuring the stability and continuity of the soil during the test.

[0053] This embodiment, by setting up a first filter layer, a second filter layer, geotextile, and a permeable plate 14, can avoid soil and water loss at the bottom of the settlement column 11, better simulate the self-weight deposition law of silt in the actual environment, and make the test results of the entire test device more accurate.

[0054] In some embodiments, the deposition assembly 1 further includes a second sealing ring and a plurality of first sealing rings 15. The number of first sealing rings 15 corresponds one-to-one with the number of sleeves 111, and a first sealing ring 15 is provided between two adjacent sleeves 111. The second sealing ring is provided at the connection between the sedimentation column 11 and the base 12. In this embodiment, in order to better improve the connection sealing between the two sleeves 111, a groove can be provided on the end face of the sleeve 111. When two adjacent sleeves 111 are spliced ​​together, the grooves of the two sleeves 111 can communicate to form an annular cavity. The first sealing ring 15 is then placed in the annular cavity. When the two sleeves 111 are spliced ​​together, the first sealing ring 15 in the annular cavity will be squeezed, thereby ensuring the sealing at the connection between the two adjacent sleeves 111.

[0055] The second sealing ring is disposed between the base 12 and the sleeve 111 connected to the base 12, and has the same function as the first sealing ring 15.

[0056] Furthermore, in some embodiments, the sleeve 111 is made of acrylic sheet; and / or, the base 12 is made of rigid polyvinyl chloride; and / or, the permeable plate 14 is made of rigid polyvinyl chloride; and / or, the first sealing ring 15 and / or the second sealing ring are O-rings; and / or, the cover plate 13 is made of acrylic sheet; and / or, the housing 3 is made of acrylic sheet.

[0057] In some embodiments, the sleeve 111 has a diameter of 200 mm, a height of 200 mm, and a wall thickness of 10 mm; and / or, the first sealing ring 15 has a diameter of 180 mm; and / or, the second sealing ring has a diameter of 180 mm; and / or, the base 12 has a diameter of 240 mm and a height of 20 mm; and / or, the permeable plate 14 has a diameter of 180 mm and is circular.

[0058] In some embodiments, the deposition assembly 1 further includes an electronic scale 16 disposed below the base 12. The electronic scale 16 is used to detect the weight of the soil within the settlement column 11. The electronic scale 16, placed below the base 12, is used to measure the weight change of the settlement column 11. Through the precise measurement of the electronic scale 16, the state of silt deposition can be monitored in real time.

[0059] In some embodiments, the coaxial cable detector 41 includes an electromagnetic wave generator and an oscilloscope. The electromagnetic wave generator is used to generate a square high-frequency electromagnetic wave signal, and the oscilloscope is used to analyze the feedback time of the square high-frequency electromagnetic wave signal.

[0060] Please see Figure 4 In some embodiments, the probe assembly further includes an insulating handle 43, on which a plurality of waveguide rods 42 are disposed, and the coaxial cable detector 41 is connected to the plurality of waveguide rods 42 via the insulating handle 43. In some embodiments, the number of waveguide rods 42 is three.

[0061] In some embodiments, the base 12 is provided with a connection hole 121, one end of which communicates with the interior of the settlement column 11, and the other end of which communicates with the second drainage pipe 22. The testing device also includes a control valve 5, which is disposed on the second drainage pipe 22. The control valve 5 can be opened or closed according to actual testing needs, thereby enabling data collection of the soil formed by silt in the settlement column 11 under different conditions.

[0062] To facilitate understanding, the following examples are provided to further illustrate the above technical solutions:

[0063] This example provides a non-destructive testing device for measuring the change in water content during the self-weight deposition of high-water-content sludge. The device includes a deposition component 1, a drainage component 2, a housing 3, and a testing component 4. The deposition component 1 includes a sedimentation column 11, an acrylic cover plate 13, a rigid polyvinyl chloride (PVC) permeable plate 14, a control switch (control valve 5), a rigid PVC base 12, an electronic scale 16, and a guide pipe (second drainage pipe 22). The column body of the sedimentation column 11 is securely connected to the base 12. A precise ruler (graduation line) can be attached to the outer wall of the sedimentation column 11. Furthermore, a coaxial cable detector 41 and a probe (i.e., a waveguide rod 42 with an insulated handle 43) connected to the sedimentation column 11 are mounted on the outer wall of the sedimentation column 11 to enhance monitoring capabilities.

[0064] Test assembly 4 consists of a settlement column 11 cover (i.e., housing 3) mounted on top of the settlement column 11. Coaxial cable detectors 41 and probes (i.e., waveguide rods 42 with handles) are installed at intervals around and above and below the settlement column 11 cover, ensuring that the waveguide rods 42 are in precise contact with the settlement column 11. The coaxial cable detector 41 includes an electromagnetic wave generator and an oscilloscope. The electromagnetic wave generator outputs a square high-frequency electromagnetic wave signal with a very fast rise time (120 ps); the oscilloscope receives and analyzes the feedback time of the square electromagnetic wave. The probes used are three parallel waveguide rods 42, each fixed to an insulating handle 43 made of waterproof, rigid insulating material, and connected to the coaxial cable detector 41 via cables.

[0065] The settling column 11 is made of acrylic sheet, and the transparency of the acrylic sheet allows for direct observation of the settling process. The settling column 11 is 1000mm high, 200mm in inner diameter, and 10mm thick, and can be divided into five assemblyable sections (i.e., sleeves 111). Each section (i.e., sleeve 111) is equipped with a drainage pipe (i.e., the first drainage pipe 21) on its side. The assembly sections (i.e., sleeves 111) are connected by bolts and sealed with O-rings (i.e., the first sealing ring 15). The bottom of the settling column 11 is equipped with a control switch (i.e., control valve 5) and a guide pipe (i.e., the second sealing ring). The entire settling column 11 is placed on an electronic scale 16 to achieve accurate measurement of changes in sludge weight.

[0066] An acrylic cover 13 is installed on top of the settling column 11. Its purpose is to prevent the evaporation of moisture from the sample within the test apparatus during the test, after the test begins. Simultaneously, the acrylic cover 13 protects the interior of the settling column 11 from external interference and facilitates observation and operation. This design effectively protects the testing apparatus and ensures the accuracy and stability of the experiment.

[0067] The rigid polyvinyl chloride permeable plate 14 is placed at the bottom of the settling column 11, mainly to prevent soil particles from being lost from the bottom. The permeable plate 14 has a certain porosity structure, which allows water to drain freely while effectively preventing the loss of soil particles, ensuring the stability and continuity of the soil during the experiment.

[0068] The control switch (i.e., control valve 5) is installed at the bottom of the settling column 11 and connected to the rigid polyvinyl chloride base 12. By opening and closing the control switch (i.e., control valve 5), the drainage rate and drainage volume are adjusted, thereby simulating the soil drainage process under different conditions and further studying the drainage performance and stability of the soil.

[0069] A rigid PVC base 12 is installed at the bottom of the settling column 11. The base 12 is made of rigid PVC, a material with good corrosion resistance and stability, suitable for long-term testing. The base 12 and the settling column 11 are fixedly connected using organic adhesive, ensuring the stability and sealing of the device.

[0070] An electronic scale 16 is placed below the base 12 to measure the weight change at the bottom of the sediment column. The precise measurement by the electronic scale 16 allows for real-time monitoring of the weight changes in the sludge deposition.

[0071] The guide pipe (i.e., the second drain pipe 22) is connected to a control switch (i.e., control valve 5) to guide the water flow to the outside.

[0072] The specific fabrication and operation process of the test device shown in this example is as follows:

[0073] To construct the segmented, assembled settlement column 11, O-rings (first sealing rings 15) with precisely matched inner diameters must be installed at the connection ports of each sleeve 111 to ensure a tight seal. Each sleeve 111 connection port is secured with bolts to ensure a stable and leak-free connection. Paper rulers with a minimum scale of 1mm are symmetrically affixed to the outer wall of the settlement column 11 and fixed with transparent tape for accurate measurement. A rigid PVC permeable plate 14, made of rigid PVC material, is installed as a filter layer, its main function being to effectively prevent excessive loss of soil particles during the experiment.

[0074] Before starting the experiment, ensure all control switches (control valve 5) are closed and keep the apparatus dry. During the experiment, apply petroleum jelly evenly to the inner wall of the settlement column 11 to reduce friction during silt settling and ensure smooth experiment execution. To prevent soil loss at the bottom, a moistened filter layer should be laid at the bottom of the settlement column 11 in the following order: filter paper (first filter layer), geotextile, grooved permeable board 14, and another layer of filter paper (second filter layer) to maintain experimental accuracy.

[0075] Next, install the coaxial cable detector 41 and its probe (i.e., the insulated handle 43 with the waveguide rod 42), and adjust the position and parameters of the coaxial cable detector 41 to monitor changes in the moisture content of the silt. After assembly, conduct a leak test by filling the joints with water to check for any leakage. Finally, perform a comprehensive inspection to ensure that all components are correctly installed and the monitoring equipment is functioning properly, preparing for the successful conduct of the experiment.

[0076] Before conducting the experiment, different concentrations of silt should be prepared according to the experimental requirements. This step requires a mixer to break up the original soil and prepare silt of different concentrations according to the experimental requirements. The preparation process must be strictly carried out according to the mixing ratio requirements to ensure the reliability and accuracy of the experimental results. When transferring the prepared high-moisture-content sandy silt to the settling column 11, the settling column 11 is sealed with an acrylic glass cover plate 13. The slurry suspension begins to settle freely under its own weight. The readings are recorded according to the scale on the outer wall of the acrylic glass tube column. During the settling process, photos are taken to record the actual settling height of the turbid liquid surface for archiving. At the same time, it is necessary to carefully observe whether there is any water seepage at the cemented connection between the column and the base 12. If water seepage is found, it needs to be dealt with in time to ensure that the connection is well sealed to prevent leakage during the experiment, thereby ensuring the accuracy and reliability of the experimental data.

[0077] While activating the coaxial cable detector 41, we ensure that the total power of its electromagnetic wave generator remains constant. This allows us to monitor the particle distribution within the sedimentation column 11 in real time during the sludge deposition process, enabling precise recording of the particle distribution at any given moment.

[0078] When electromagnetic waves pass through matter, absorption and scattering occur, resulting in varying speeds. The speed also depends on the extent to which the electromagnetic wave travels.

[0079] To improve the reliability and accuracy of the test data, the experiment can be repeated using high-moisture-content sludge with different properties and compositions until all test data is collected, thus ensuring the reliability and scientific validity of the results. Once the predetermined sedimentation and drainage conditions are met, the experiment should be terminated, and all equipment should be safely shut down.

[0080] The following is an explanation of the testing principle:

[0081] The coaxial cable detector includes an electromagnetic wave generator and an oscilloscope, and the probe used consists of three parallel waveguide rods. The time T required for the electromagnetic wave to travel from emission to reception (through the soil) is given by the formula (1), which is as follows:

[0082] V = C / (Kμ) -0.5 =L / T;

[0083] In formula (1), C is the speed of electromagnetic wave propagation in vacuum, which is a constant of 300 km / s; K is the dielectric constant of the medium; μ is the magnetic coefficient of the medium, and the magnetic coefficient of soil is 1; L is the propagation distance of electromagnetic wave in the medium; and T is the propagation time of electromagnetic wave in the medium. From this, formula (2) for the dielectric constant of rock and soil can be obtained, as follows:

[0084] K = (CT / 2L) 2 ;

[0085] In formula (2), C and L are known, and T can be measured. Therefore, the dielectric constant K of the measured soil can be calculated. Soil consists of three phases: solid (soil particles), liquid (pore water), and gas (pore gas). The dielectric constant of soil particles is generally around 2-4, the dielectric constant of air is 1, and the dielectric constant of water is usually around 80. The dielectric constants of air and soil particles are much smaller than those of water. Changes in the dielectric constant caused by variations in air and soil particles are negligible. Therefore, the dielectric constant of soil depends on its moisture content. Thus, by establishing the relationship between the dielectric constant and the soil moisture content, the moisture content of the soil can be obtained from the measured dielectric constant.

[0086] Tests were conducted on different soils, and the relationship between the soil dielectric constant and the volumetric water content was established using formula (3), which is as follows:

[0087] K = 3.03 + 9.3θ + 146θ 2 —76.7θ 3 ;

[0088] In formula (3), θ is the volumetric water content of the soil (the ratio of the volume of water in the soil to the total volume of water in the soil), in percentage. The conversion relationship between volumetric water content and mass water content is expressed by formula (4), which is as follows:

[0089] θ = ρw / (1+w);

[0090] In formula (4), ρ is the density of the soil, θ is the volumetric water content of the soil, and w is the mass water content of the soil.

[0091] After measuring the dielectric constant of the silt inside the settlement column 11 using a coaxial cable detector 41, the volumetric water content of the soil can be calculated using formula (3). Furthermore, the density inside the settlement column 11 can be non-destructively measured using existing X-ray technology, and the commonly used mass water content w can be obtained using formula (4). Since the coaxial cable detector 41 and its probe are installed at intervals around the perimeter and top and bottom of the cover, we can plot a curve showing the relationship between different heights and the silt water content. This curve allows for precise control of the water content distribution of silt at various heights.

[0092] Specifically, in this example, the main structure of the sedimentation column 11 is made of transparent plexiglass, including the sides and bottom, to facilitate direct observation of the sample deposition process. The height of the measuring section is set at 1.5 meters and is graduated to accurately determine the sample height during experimental preparation. The bottom of the sedimentation column 11 has a sample chamber that can hold standard samples of different sizes according to experimental needs. The entire sedimentation column 11 consists of five detachable sections, connected by flanges and bolts to ensure fixation and sealing. Drainage outlets are provided at the bottom of the side walls of the sedimentation column 11 for easy cleaning of the equipment after the experiment.

[0093] A scale is set on the settling column 11, i.e., the waveguide rod 42 is positioned at a certain height. The electromagnetic wave generated by the electromagnetic wave generator is guided by the probe to propagate in the medium. When the electromagnetic wave reaches the end of the transmission path or encounters a point of impedance discontinuity, part of the signal is reflected back. The reflected signal returns along the original path and is captured by the sampling oscilloscope. By analyzing the time difference between the reflected signal and the original transmitted signal, and comparing the feedback time of the electromagnetic wave with the calibrated relationship curve, the corresponding water content is obtained, thereby obtaining the water content distribution of silt at different heights.

[0094] This example allows direct observation of the development of sedimentation and consolidation of the dredged fill sample over time. At the location where the coaxial cable detector 41 is installed, the water content of the silt can be detected using electromagnetic waves. Since the coaxial cable detector 41 is installed at intervals around and above and below the settlement column 11, the user can plot curves showing the relationship between different heights and the water content of the silt, thus obtaining the settlement curves of the dredged fill particles.

[0095] During the first hour of the silt moisture content measurement and pore pressure measurement, the electromagnetic wave generator was turned on every ten minutes to measure the sedimentation column 11, that is, the moisture content of the soil sample was measured at six times: 15min, 25min, 35min, 45min, 55min, and 65min.

[0096] One scan was defined as the electromagnetic wave measuring device measuring the soil sample's moisture content every 5 cm from top to bottom, obtaining the distribution of the soil sample's moisture content with height at that moment by comparing it with a standard sample. Over the next three hours, the soil sample was scanned every 30 minutes, measuring the moisture content at 90 min, 120 min, 150 min, 180 min, 210 min, and 240 min. Because the deposition and consolidation rate of particles gradually slows down over time, subsequent test intervals can be adjusted based on the changes in data between consecutive measurements. Additionally, the pore pressure data measured by each pore pressure sensor at each time point was recorded. The experiment ended when the measured silt moisture content remained consistent and unchanged, and the pore pressure data measured by the pore pressure sensors also ceased to change.

[0097] This example has the following beneficial effects:

[0098] The sedimentation column 11 is made of acrylic sheet, which has high strength and can withstand large water pressure; the tube wall of sedimentation column 11 is uniform and transparent, which makes it easy to read the liquid level; the connection between the tube wall of sedimentation column 11 and the base 12 has high strength, high durability and good sealing performance, and there is no leakage or seepage during the test; the processing and manufacturing process of sedimentation column 11 is simple.

[0099] Compared to traditional soil self-weight sedimentation drainage test devices, the settlement column 11 in this example is equipped with a settlement column 11 cover. Coaxial cable detectors 41 are installed at intervals around and above and below the settlement column 11 cover to ensure that the waveguide rod 42 is in precise contact with the settlement column 11. By measuring the difference in the time required for electromagnetic waves to travel from emission to reception (through the soil) using oscilloscopes at different heights, the relationship curve between the electromagnetic wave feedback time and the water content can be obtained, allowing for rapid calibration of the mud water content at different heights.

[0100] Compared with traditional soil self-weight deposition drainage test devices, the test device described in this example is equipped with a coaxial cable detector 41 and a waveguide rod 42. It uses an oscilloscope to receive and analyze the feedback time of electromagnetic waves, and quickly and non-destructively measures the change in water content of silt at different heights during self-weight deposition.

[0101] Compared to traditional soil self-weight sedimentation drainage test apparatuses, the settlement column 11 of the test apparatus described in this example adopts a modular, segmented assembly design, which improves the portability and ease of assembly of the apparatus. When conducting experiments in different locations, this modular design significantly reduces the complexity of transportation and installation. The segmented, detachable nature of the settlement column 11 provides flexibility for experiments, facilitating diverse experimental layouts and supporting complex modular experiments. For example, different sections can be filled with different types of silt or embedded with various sensors to explore the interactions between multiple layers of silt. The construction using bolted connections and O-ring seals not only ensures a tight connection between the segments of the settlement column 11 but also enhances the overall stability and sealing, which is particularly crucial for conducting long-term or harsh-condition experiments.

[0102] Compared to traditional soil self-weight deposition and drainage test devices, the test apparatus described in this example innovatively introduces a design that connects a control switch (control valve 5) to a guide pipe (second drainage pipe 22). This design greatly improves the convenience and flexibility of experimental operation. By operating the control switch, the experimenter can precisely open or close the guide pipe, thereby finely controlling the water flow state inside the device. The presence of the guide pipe allows the water flow to be directed to a specific location as needed, effectively controlling the direction and flow rate of the water during the experiment. This design makes the experiment more closely resemble the water flow conditions in actual engineering, significantly enhancing the authenticity and reliability of the experiment. In addition, the design of the control switch and guide pipe simplifies the operation process, reduces experimental steps, and thus significantly improves experimental efficiency.

[0103] Unlike existing technologies, the above technical solution provides a non-destructive moisture content testing device for silt self-weight deposition, including a deposition component 1, a drainage component 2, a shell 3, and a testing component 4. The settling column 11 is used to simulate the self-weight deposition process of dredged sludge with high moisture content, and the coaxial cable detector 41 is used to measure the silt moisture content. The coaxial cable detector 41 can quickly and non-destructively measure the changes in silt moisture content at different heights during self-weight deposition, and can be used in engineering for rapid quantitative analysis of silt moisture distribution during self-weight deposition. The settling column 11 is equipped with a shell 3 on its outer side, and probe groups are installed at intervals around and above and below the settling column 11 to ensure that the waveguide rod 42 is in precise contact with the settling column 11. By observing the difference in the time required for electromagnetic waves received by the coaxial cable detector 41 at different heights to reach the soil within the settling column 11 and the time required for these waves to reach the soil, the relationship curve between the electromagnetic wave feedback time and the moisture content is obtained, allowing for rapid calibration of the sludge moisture content at different heights.

[0104] The above description is only a part of the embodiments of this utility model, and does not limit the scope of protection of this utility model. Any equivalent device or equivalent process transformation made based on the contents of this utility model specification and drawings, or direct or indirect application in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A non-destructive moisture content testing device for silt gravity deposition, characterized in that, include: A sedimentation assembly includes a sedimentation column, a base, and a cover plate. The sedimentation column is vertically mounted on the base, and the cover plate covers the top of the sedimentation column. The sedimentation column has scale lines on its exterior, and the sedimentation column contains soil formed by the silt. The drainage assembly includes a first drainage pipe group and a second drainage pipe group. The first drainage pipe group includes a plurality of first drainage pipes, which are spaced apart from top to bottom along the axial direction of the settling column, and each first drainage pipe is connected to the settling column. The second drainage pipe group includes at least one second drainage pipe, which is connected to the settling column through the base. A shell, covering the periphery of the settling column; Test components are disposed on the housing. There are multiple test components, which are distributed at intervals from top to bottom along the axial direction of the housing. Each test component includes multiple probe groups, and the multiple probe groups of the same test component are distributed at intervals along the circumference of the settlement column. Each of the probe groups includes a coaxial cable detector and at least one waveguide rod, the waveguide rod being disposed on the housing, the end of the waveguide rod abutting against the outer side of the settlement column, the coaxial cable detector being connected to the waveguide rod, and the coaxial cable detector being used to emit electromagnetic waves toward the soil within the settlement column and to receive electromagnetic waves from the soil within the settlement column.

2. The non-destructive moisture content testing device for silt gravity deposition according to claim 1, characterized in that, The deposition assembly also includes: Multiple sleeves are detachably connected from top to bottom by fasteners, and two adjacent sleeves are airtightly connected to form the settling column. Each sleeve is provided with at least one first drain pipe and at least one test component.

3. The non-destructive moisture content testing device for silt gravity deposition according to claim 2, characterized in that, The deposition assembly also includes: A first filter layer is disposed on the base, and the first filter layer is configured as filter paper wetted with distilled water; Geotextile is placed on the first filter layer; A permeable board is installed on the geotextile, and the permeable board is adapted to the settlement column; A second filter layer is disposed on the permeable plate, and the second filter layer is configured as filter paper wetted with distilled water.

4. The non-destructive moisture content testing device for silt gravity deposition according to claim 3, characterized in that, The deposition assembly also includes: Multiple first sealing rings are provided, the number of which corresponds one-to-one with the number of sleeves, and one first sealing ring is provided between two adjacent sleeves. The second sealing ring is located at the connection between the settling column and the base.

5. The non-destructive moisture content testing device for silt gravity deposition according to claim 4, characterized in that, The sleeve is made of acrylic sheet; And / or, the base is made of rigid polyvinyl chloride; And / or, the permeable panel is made of rigid polyvinyl chloride; And / or, the first sealing ring and / or the second sealing ring are O-rings; And / or, the cover plate is made of acrylic sheet; And / or, the shell is made of acrylic sheet.

6. The non-destructive moisture content testing device for silt gravity deposition according to claim 4, characterized in that, The sleeve has a diameter of 200mm, a height of 200mm, and a wall thickness of 10mm. And / or, the diameter of the first sealing ring is 180 mm; And / or, the diameter of the second sealing ring is 180 mm; And / or, the diameter of the base is 240mm and the height of the base is 20mm; And / or, the permeable plate has a diameter of 180 mm and is circular.

7. The non-destructive moisture content testing device for silt gravity deposition according to claim 1, characterized in that, The deposition assembly also includes: An electronic scale is located below the base and is used to detect the weight of the soil inside the settlement column.

8. The non-destructive moisture content testing device for silt gravity deposition according to claim 1, characterized in that, The coaxial cable detector includes: An electromagnetic wave generator, which is used to generate square high-frequency electromagnetic wave signals; An oscilloscope, used to analyze the feedback time of the square high-frequency electromagnetic wave signal.

9. The non-destructive moisture content testing device for silt gravity deposition according to claim 1, characterized in that, The probe assembly also includes: An insulating handle is provided, on which multiple waveguide rods are provided, and the coaxial cable detector is connected to the multiple waveguide rods through the insulating handle.

10. The non-destructive moisture content testing device for silt gravity deposition according to claim 1, characterized in that, The base is provided with a connection hole, one end of which communicates with the interior of the settling column, and the other end of which communicates with the second drainage pipe. The testing device further includes: The control valve is installed on the second drain pipe.

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