A dynamic permeability coefficient measuring device and its measuring system and measuring method

Abstract

The present invention discloses a dynamic permeability coefficient measuring device and its measuring system and measuring method, which include a sample fixing mechanism and a permeate supply mechanism; the sample fixing mechanism includes a sample storage tube storing a soil sample, the sample storage tube extends vertically, and a liquid inlet and a liquid outlet are respectively provided at the top and bottom ends thereof; two overflow holes covered by the soil sample are provided on the side wall of the sample storage tube, and the two overflow holes are respectively located at positions corresponding to the bottom and top of the soil sample, and the two overflow holes are connected to a liquid level pipe; the liquid inlet is connected to the permeate supply mechanism, and a water seepage structure for supporting the soil sample is provided at the liquid outlet, which solves the problem that the test size of the existing device is limited and the permeability coefficient cannot be monitored over time during the process of fluid injection into sand in low disturbance and in real time in situ, and the efficiency of the test measurement is improved.

Description

Technical Field

[0001] The invention relates to the technical field of soil permeability testing, and in particular to a dynamic permeability coefficient measuring device and a measuring system and a measuring method thereof. Background Art

[0002] At present, there are still many defects and drawbacks in the soil dynamic permeability determination device in the process of microbial mineralization, which often cause significant errors in the test results. The main reason is that the measurement device has a single size and it is difficult to control the saturation state of the sample. In the microbial mineralization test, depending on the purpose of the test, the final sample size is quite different from the required size of the existing measurement device, making the test sample unsuitable for the existing measurement device. In addition, in the process of using the existing measurement device, there is a large disturbance to the mineralized soil block, the test process is cumbersome, and the sample test size is unreasonable, resulting in the inability to effectively and reliably measure the soil permeability of the microbial mineralized improved soil. At the same time, the existing device cannot achieve low disturbance and in-situ dynamic permeability determination. In addition, the filtrate generated by the permeability test cannot be effectively recovered for secondary liquid detection, and the measurement device is mostly an opaque mold, which makes it difficult to observe the curing effect during the mineralization process. Summary of the invention

[0003] The purpose of the present invention is to provide a dynamic permeability coefficient measuring device and its measuring system and measuring method to solve the problems existing in the above-mentioned prior art, solve the problems that the test size of the existing device is limited, and the permeability coefficient cannot be low-disturbed and in-situ real-time monitoring of the change of permeability over time during the injection of fluid into sand, and improve the efficiency of the test measurement.

[0004] To achieve the above-mentioned object, the present invention provides the following solutions: The present invention provides a dynamic permeability coefficient measuring device, including a sample fixing mechanism and a permeate supply mechanism;

[0005] The sample fixing mechanism comprises a sample storage tube storing a soil sample, the sample storage tube extends vertically, and a liquid inlet and a liquid outlet are respectively provided at the top and bottom of the sample storage tube, and two overflow holes covered by the soil sample are provided on the side wall of the sample storage tube, and the two overflow holes are respectively located at positions corresponding to the bottom and top of the soil sample, and the two overflow holes are connected to a liquid level tube;

[0006] The liquid inlet is connected to the permeate supply mechanism, and the liquid outlet is provided with a water seepage structure for supporting the soil sample.

[0007] Preferably, the sample storage tube is provided with a plurality of observation hole groups at equal intervals along the circumferential direction, each of the observation hole groups includes a plurality of observation holes penetrating the sample storage tube along the thickness direction, each of the observation holes is equally spaced along the vertical direction of the sample storage tube, and each of the observation holes is sealed with a transparent waterproof tape.

[0008] Preferably, the two observation holes respectively corresponding to the top and bottom positions of the soil sample are both used as the overflow holes, and the observation holes serving as the overflow holes are not provided with the transparent waterproof tape.

[0009] Preferably, the water seepage structure includes a support trough body with an opening on the top, the bottom end of the sample storage tube extends into the support trough body from the opening, a drainage layer supported below the liquid outlet is laid in the support trough body, and a drainage port located below the drainage layer is opened on the bottom wall of the support trough body.

[0010] Preferably, the drainage layer includes a permeable stone layer and a filter cloth layer, the permeable stone layer is laid on the inner bottom of the support trough body and covers the top of the drainage port, and the filter cloth layer covers the top surface of the permeable stone layer and is supported below the liquid outlet.

[0011] Preferably, the permeate supply mechanism comprises a permeate container and an infusion tube, one end of the infusion tube is connected to the permeate container, and the other end is connected to the liquid inlet, and the infusion tube is provided with a delivery pump for adjusting the infusion rate.

[0012] Preferably, the permeate container is equipped with a support seat, a drive motor and a rotating magnet connected to the output shaft of the drive motor are provided in the support seat, the permeate container is arranged on the support seat, and a magnetic rotor that rotates synchronously with the rotating magnet is provided in the permeate container.

[0013] Preferably, the liquid discharge port is connected to a permeate collection container.

[0014] A determination system is also provided, comprising a first porous plate and a second porous plate movably arranged above the first porous plate in a vertical direction, wherein a plurality of the sample fixing mechanisms are arranged between the first porous plate and the second porous plate;

[0015] The supporting grooves of each of the sample fixing mechanisms are supported on the first porous plate, and the second porous plate abuts against the top of the sample storage tube of each of the sample fixing mechanisms;

[0016] A plurality of the delivery pipes are connected in parallel at the delivery pump outlet of the permeate supply mechanism, and each of the delivery pipes passes through a through hole on the second porous plate and is connected to the liquid inlet of the corresponding sample storage tube.

[0017] A determination method is also provided, comprising the following steps:

[0018] Preparation of permeate: put the permeate used in the test into the permeate container, and drive the magnetic rotor to rotate through the driving motor and the rotating magnet to stir the permeate evenly;

[0019] Installation of the sample fixing mechanism: a permeable stone layer is laid on the bottom of the inner side of the supporting tank body and covered above the drainage port, a filter cloth layer is covered on the top surface of the permeable stone layer, the bottom end of the sample storage tube is supported on the top surface of the filter cloth layer, and the liquid level tube is installed at the corresponding overflow hole on the sample storage tube according to the height of the soil sample;

[0020] Soil sample preparation: filling the air-dried soil sample or pre-treated soil into the sample storage tube and filling it to the required height;

[0021] Preparation before the permeation test: prepare multiple sets of the sample fixing mechanisms, and install the supporting troughs of each of the sample fixing mechanisms on the first porous plate, and overlap the second porous plate on the top of the sample storage tube of each of the sample fixing mechanisms;

[0022] The liquid outlet end of each delivery tube passes through the through hole on the second porous plate and is connected to the liquid inlet of the corresponding sample storage tube, and the liquid inlet end of each delivery tube is connected to the outlet of the delivery pump;

[0023] Start the permeation test: inject the permeate into each of the sample storage tubes through the delivery pump, and after the permeation rate stabilizes, control the permeation rate to keep the liquid surface of the permeate tangent to the overflow hole above, and record the running time, the flow rate of the permeate and the volume of the liquid flowing through the soil sample;

[0024] The water head difference in the two overflow pipes is measured to obtain the real-time water level difference, and then the real-time permeability coefficient of the soil sample is calculated according to the height of the soil sample between the two overflow holes, the cross-sectional area of ​​the soil sample and the flow rate of the permeate.

[0025] Compared with the prior art, the present invention has achieved the following technical effects:

[0026] The entire device stores soil samples through a sample storage tube, and the soil samples are fixed by the sample storage tube, and supported by a water seepage structure to avoid large disturbances to the soil samples during the measurement process, thereby ensuring the final size of the soil samples, thereby ensuring effective and reliable soil permeability coefficient measurement of microbial mineralized improved soil. The problem that the test size of the existing device is limited and the permeability coefficient cannot be low-disturbed and in-situ real-time monitoring of the change of permeability coefficient over time during the injection of fluid into sand is solved. Moreover, the soil sample structure is finalized by the sample storage tube, and two overflow pipes are set and the water head difference in the two overflow pipes is measured to obtain the real-time water level difference, so that the permeability of the soil sample can be quickly obtained in combination with parameters such as the size of the soil sample and the water level difference, thereby improving the efficiency of the test measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 It is a front view of the overall structure of the present invention;

[0029] Figure 2 The sample fixing mechanism and the first porous plate and the second porous plate of the present invention are shown in FIG. Figure 1 ;

[0030] Figure 3 The sample fixing mechanism and the first porous plate and the second porous plate of the present invention are shown in FIG. Figure 2 ;

[0031] Figure 4 The sample fixing mechanism and the first porous plate and the second porous plate of the present invention are shown in FIG. Figure 3 ;

[0032] Figure 5 This is a schematic diagram of the vertical nozzle structure of the present invention;

[0033] Figure 6 It is a schematic diagram of the structure of the sample fixing mechanism of the present invention;

[0034] Among them, 1-display screen, 2-flow rate control knob, 3-delivery pump, 4-infusion tube, 5-needle fixing bracket, 6-liquid delivery needle, 7-needle catheter, 8-first porous plate, 9-second porous plate, 10-adjusting nut, 11-adjusting screw, 12-circular plate part, 13-support trough body, 14-circular tube part, 15-permeable stone layer, 16-transparent film, 17-observation hole, 18-liquid level tube, 19-water nozzle, 20-adjusting tube, 21-permeate collection container, 22-permeate container, 23-magnetic rotor, 24-rotating magnet, 25-support seat, 26-sample storage tube. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] The purpose of the present invention is to provide a dynamic permeability coefficient measuring device and its measuring system and measuring method to solve the problems existing in the above-mentioned prior art, solve the problems that the test size of the existing device is limited, and the permeability coefficient cannot be low-disturbed and in-situ real-time monitoring of the change of permeability over time during the injection of fluid into sand, and improve the efficiency of the test measurement.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0038] like Figures 1 to 6 As shown, this embodiment provides a dynamic permeability coefficient measuring device, including a sample fixing mechanism and a permeate supply mechanism; the sample fixing mechanism includes a sample storage tube 26 storing a soil sample, preferably the sample storage tube 26 adopts an organic glass round tube, and a transparent film 16 is laid on the inner wall of the sample storage tube 26 to prevent the soil sample from adhering to the sample storage tube 26, the sample storage tube 26 extends vertically, and a liquid inlet and a liquid outlet are respectively opened at the top and bottom ends thereof, and two overflow holes are opened on the side wall of the sample storage tube 26, both of which are covered by the soil sample, and the two overflow holes are respectively located at the positions corresponding to the bottom and the top of the soil sample, and the two overflow holes are connected to a liquid level tube 18, preferably the liquid level tube 18 adopts a glass tube, and is vertically installed at the corresponding overflow hole according to the height of the soil sample to measure the real-time water level difference; the liquid inlet is connected to the permeate supply mechanism, and a water seepage structure for supporting the soil sample is provided at the liquid outlet, and the soil sample is supported by the water seepage structure to avoid the soil sample from being lost when the soil sample flows out with the permeate. The permeate supply mechanism injects permeate into each sample storage tube 26, and the permeate is discharged from the liquid outlet to saturate the soil sample. After the seepage rate stabilizes, the seepage rate is controlled to keep the liquid surface of the permeate tangent to the overflow hole above, and the operation time, the permeate liquid flow rate and the volume of the liquid flowing through the soil sample are recorded; the water head difference in the two overflow pipes is measured to obtain the real-time water level difference, and then the real-time permeability coefficient of the soil sample is calculated based on the soil sample height between the two overflow holes, the cross-sectional area of ​​the soil sample and the permeate flow rate.

[0039] The entire device stores soil samples through the sample storage tube 26, and the soil samples are fixed by the sample storage tube 26, and supported by the water seepage structure to avoid large disturbances to the soil samples during the measurement process, thereby ensuring the final size of the soil samples, thereby ensuring effective and reliable soil permeability coefficient measurement of microbial mineralized improved soil. The problem that the test size of the existing device is limited and the permeability coefficient cannot be low-disturbed and in-situ real-time monitoring of the change of permeability coefficient over time during the injection of fluid into sand is solved. Moreover, the soil sample structure is finalized by the sample storage tube 26, and two overflow pipes are set and the water head difference in the two overflow pipes is measured to obtain the real-time water level difference, so that the permeability of the soil sample can be quickly obtained in combination with parameters such as the size of the soil sample and the water level difference, thereby improving the efficiency of the test measurement.

[0040] As a preferred embodiment of the present invention, the sample storage tube 26 is provided with a plurality of groups of observation holes 17 at equal intervals along the circumferential direction, each group of observation holes 17 includes a plurality of observation holes 17 penetrating the sample storage tube 26 along the thickness direction, each observation hole 17 is evenly spaced along the vertical direction of the sample storage tube 26, and each observation hole 17 is blocked with a transparent waterproof tape. The observation holes 17 are blocked by the transparent waterproof tape, and the soil sample in the sample storage tube 26 can be observed through the observation holes 17 and the transparent waterproof tape to adjust the efficiency of the permeate supply in real time.

[0041] Furthermore, the two observation holes 17 corresponding to the top and bottom positions of the soil sample are both used as overflow holes, and the observation holes 17 used as overflow holes are not provided with transparent waterproof tape. By selecting two corresponding observation holes 17 as overflow holes, there is no need to open overflow holes, thereby reducing the production cost.

[0042] As a preferred embodiment of the present invention, the water seepage structure includes a support trough body 13 with an opening at the top. The support trough body 13 is preferably made of organic glass. The bottom end of the sample storage tube 26 extends into the support trough body 13 through the opening. A drainage layer supported below the liquid outlet is laid in the support trough body 13, and a drainage port located below the drainage layer is opened on the bottom wall of the support trough body 13. Specifically, during the preparation process, the support trough body 13 is divided into a circular tube portion 14 and a circular plate portion 12. The circular tube portion 14 is made of organic glass, and the circular plate portion 12 is made of PP acid and alkali resistant material. Both ends of the circular tube portion 14 are open and surround the liquid outlet of the sample storage tube 26. The circular plate portion 12 is sealed at the bottom end of the circular tube portion 14. The drainage port is opened on the circular plate portion 12, and the drainage layer is contained in the circular tube portion 14 and laid flat on the circular plate portion 12.

[0043] Furthermore, the drainage layer includes a permeable stone layer 15 and a filter cloth layer. Preferably, the permeable stone layer 15 is made of silicon carbide permeable stone, and the filter cloth layer is made of non-woven fabric. The permeable stone layer 15 is laid on the inner bottom of the support trough 13 and covers the top of the drainage port. The filter cloth layer covers the top surface of the permeable stone layer 15 and is supported below the drainage port. The permeate can be quickly discharged through the permeable stone layer 15, and the filter cloth layer can prevent the soil sample from being deposited in the permeable stone layer 15, thereby reducing the impact on the soil sample structure.

[0044] Moreover, the permeate supply mechanism includes a permeate container 22 and a liquid infusion tube 4, one end of the liquid infusion tube 4 is connected to the permeate container 22, specifically connected to the bottom position of the permeate container 22, and the other end is connected to the liquid inlet, and a delivery pump 3 for adjusting the infusion rate is provided on the liquid infusion tube 4. The delivery pump 3 is equipped with a fluid delivery control mechanism, which includes a flow rate control driver, a flow rate control knob 2, and a display screen 1. The flow rate control driver is electrically connected to the delivery pump 3. By adjusting the flow rate control knob 2 to adjust the flow rate control driver, the delivery pump 3 is adjusted to change the infusion rate of the delivery pump 3 and control the flow rate of the permeate. The display screen 1 provides real-time operation time, liquid flow rate, and volume of liquid flowing through the soil sample.

[0045] Furthermore, the permeate container 22 is equipped with a support base 25, in which a driving motor and a rotating magnet 24 connected to the output shaft of the driving motor are arranged, the permeate container 22 is arranged on the support base 25, and a magnetic rotor 23 is arranged in the permeate container 22 to rotate synchronously with the rotating magnet 24. Specifically, the driving motor and the rotating magnet 24 are located below the permeate container 22 and are not in contact with the solution, and the magnetic rotor 23 is located at the inner bottom of the permeate container 22. By clicking the electrode knob to start the driving motor, the rotating magnet 24 is triggered to rotate, causing the magnetic rotor 23 to rotate, and the permeate in the permeate container 22 is stirred evenly.

[0046] As a preferred embodiment of the present invention, the discharge port is connected to a permeate collection container 21 to collect the permeate through the permeate collection container 21. Specifically, the discharge port is connected to a water receiving nozzle 19, and the water receiving nozzle 19 is connected to the permeate collection container 21 through an adjusting pipe 20.

[0047] Furthermore, a measuring system is provided, comprising a first porous plate 8 and a second porous plate 9 movably arranged above the first porous plate 8 in a vertical direction, wherein the first porous plate 8 and the second porous plate 9 are both made of polypropylene PP punching plates, and specifically, a plurality of evenly distributed adjusting screws 11 are connected to the outer peripheral edges of the first porous plate 8 and the second porous plate 9, the adjusting screws 11 extend vertically, and are threadedly connected with adjusting nuts 10, so as to limit the positions of the first porous plate 8 and the second porous plate 9 through the adjusting nuts 10, and adjust the distance between the first porous plate 8 and the second porous plate 9, and a plurality of sample fixing mechanisms are arranged between the first porous plate 8 and the second porous plate 9;

[0048] The supporting troughs of each sample fixing mechanism are all supported on the first porous plate 8, so as to fix the position of the sample storage tube 26 through the supporting troughs. Preferably, the water receiving nozzle 19 matched with the permeate collecting container 21 is inserted into the corresponding through hole of the first porous plate 8 and is connected with the drain port. The second porous plate 9 abuts against the top of the sample storage tube 26 of each sample fixing mechanism, and then the entire sample fixing mechanism is clamped by the first porous plate 8 and the second porous plate 9.

[0049] A plurality of delivery pipes are connected in parallel at the outlet of the delivery pump 3 of the permeate supply mechanism, and each delivery pipe passes through the through hole on the second porous plate 9 respectively, and is connected to the liquid inlet of the corresponding sample storage tube 26. A vertical nozzle is connected to the outlet of the specific infusion tube 4, and the vertical nozzle includes a needle fixing bracket 5, a liquid delivery needle 6, and a needle catheter 7. The water outlet of the delivery pipe is connected to the needle catheter 7, and the needle catheter 7 and the liquid delivery needle 6 are seamlessly connected and fixed in the needle fixing bracket 5, and the entire vertical nozzle is installed at the through hole corresponding to the second porous plate 9. The specific needle fixing bracket 5 is made of rubber material and is plugged into the through hole. The needle catheter 7 and the liquid delivery needle 6 extend into the through hole along with the needle fixing bracket 5, and are connected to the liquid inlet of the sample storage tube 26.

[0050] Furthermore, a determination method is provided, comprising the following steps:

[0051] Preparation of permeate: put the permeate used in the test into the permeate container 22, and drive the magnetic rotor 23 to rotate through the driving motor and the rotating magnet 24 to stir the permeate evenly; if the permeate is water, there is no need to turn on the driving motor and the rotating magnet 24; if the permeate contains a corresponding solute, the solute is placed in the permeate container 22 according to the test plan, and the driving motor and the rotating magnet 24 are turned on, and the magnetic rotor 23 is rotated to complete the stirring of the solute in the permeate container 22;

[0052] Installation of the sample fixing mechanism: a permeable stone layer 15 is laid on the bottom of the inner side of the supporting tank body and covered above the drainage port, a filter cloth layer is covered on the top surface of the permeable stone layer 15, the bottom end of the sample storage tube 26 is supported on the top surface of the filter cloth layer, and the liquid level tube 18 is installed at the corresponding overflow hole on the sample storage tube 26 according to the height of the soil sample; preferably, a transparent waterproof tape is used to seal the corresponding overflow hole, and a transparent film 16 is laid on the inner wall of the sample storage tube 26, and a transparent waterproof cloth does not need to be set at the overflow hole for installing the overflow pipe, so that after the overflow pipe is installed, the overflow pipe is directly connected to the sample storage tube 26;

[0053] Soil sample preparation: Fill the air-dried soil sample or pre-treated soil into the sample storage tube 26 and fill it to the required height;

[0054] Preparation before permeation test: prepare multiple sets of sample fixing mechanisms, and install the supporting slots of each sample fixing mechanism on the first porous plate 8, the supporting slots of each sample fixing mechanism are evenly distributed, and the second porous plate 9 is overlapped on the top of the sample storage tube 26 of each sample fixing mechanism, and each through hole on the second porous plate 9 can be aligned with the liquid inlet of each sample storage tube 26, and the second porous plate 9 is abutted against each sample storage tube 26 by rotating the adjusting nut 10 to ensure the stability of the subsequent addition of the permeate;

[0055] The liquid outlet of each delivery tube passes through the through holes on the second porous plate 9 respectively, and is connected to the liquid inlet of the corresponding sample storage tube 26, and the liquid inlet of each delivery tube is connected to the outlet of the delivery pump 3. Specifically, the needle fixing bracket 5 is fixed at the corresponding through hole, and the needle catheter 7 and the liquid delivery needle 6 are sequentially inserted into the needle fixing bracket 5 and connected to the liquid inlet of the corresponding sample storage tube 26, and the needle catheter 7 is connected to the liquid outlet of the delivery tube;

[0056] Start the permeation test: inject the permeate into each sample storage tube 26 through the delivery pump 3 to saturate the soil sample. After the permeation rate stabilizes, control the permeation rate to keep the liquid surface of the permeate tangent to the overflow hole above, and record the operation time, the flow rate of the permeate and the volume of the liquid flowing through the soil sample;

[0057] The water head difference in the two overflow pipes is measured to obtain the real-time water level difference, and then the real-time permeability coefficient of the soil sample is calculated based on the soil sample height between the two overflow holes, the cross-sectional area of ​​the soil sample and the flow rate of the permeate.

[0058] In the determination of permeability coefficient, Darcy's law is the theoretical support of the permeability experiment, which is a law obtained from the sandy soil test. In saturated sand, the movement law of groundwater in a laminar flow state is: the amount of seepage water Q in the sand is proportional to the head difference of the seepage (h1-h2=Δh), and inversely proportional to the path L through the sand.

[0059] It can be expressed by the formula v=ki (hydraulic gradient i=Δh / L, dimensionless). Combined with the continuity equation Q=vA in hydraulics, it can be further written as Q=kiA. The Darcy formula can also be written as:

[0060]

[0061] Therefore, the permeability coefficient of the permeability test can be calculated according to the following formula:

[0062]

[0063] Where: Q—the amount of water infiltrated within t seconds (cm 3 );

[0064] L—seepage diameter (cm), equal to the sample height between the centers of the two pressure measuring holes;

[0065] A—cross-sectional area of ​​the sample (cm);

[0066] t—time (s);

[0067] h1-h2—water level difference (cm);

[0068] Note: Permeability coefficient k is a physical quantity that reflects the permeability of soil. It indicates the seepage velocity of soil under unit hydraulic gradient, and its dimension is consistent with the flow velocity. The larger the k value, the easier it is to penetrate, and the smaller the water head (energy) lost. Its value can be obtained through indoor tests or field tests. Generally, the permeability coefficient of sand is greater than that of clay.

[0069] The indoor temperature during the test is collected and recorded in real time through the fluid delivery control system. The specific fluid delivery control system is equipped with a temperature sensor for collecting the indoor temperature to obtain the permeability coefficient of the sample at the standard temperature. The specific formula is as follows:

[0070]

[0071] Where: k 20 ——Permeability coefficient of the sample at standard temperature (20°C) (cm / s);

[0072] ——The dynamic viscosity of water at T℃ (1×10 -6 kPa·s)

[0073] ——The dynamic viscosity of water at 20℃ (1×10 -6 kPa·s).

[0074] Adaptive changes made according to actual needs are all within the protection scope of the present invention.

[0075] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any reference numerals in the claims should not be regarded as limiting the claims involved.

[0076] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A dynamic permeability coefficient measuring device, characterized in that: It includes a sample fixing mechanism and a permeate supply mechanism; The sample fixing mechanism comprises a sample storage tube storing a soil sample, the sample storage tube extends vertically, and a liquid inlet and a liquid outlet are respectively provided at the top and bottom of the sample storage tube, and two overflow holes covered by the soil sample are provided on the side wall of the sample storage tube, and the two overflow holes are respectively located at positions corresponding to the bottom and top of the soil sample, and the two overflow holes are connected to a liquid level tube; The liquid inlet is connected to the permeate supply mechanism, and the liquid outlet is provided with a water seepage structure for supporting the soil sample; The sample storage tube is provided with a plurality of observation hole groups at equal intervals along the circumferential direction, each of the observation hole groups includes a plurality of observation holes penetrating the sample storage tube along the thickness direction, the observation holes are equally spaced along the vertical direction of the sample storage tube, and each of the observation holes is blocked with a transparent waterproof tape; the two observation holes corresponding to the top and bottom positions of the soil sample respectively serve as the overflow holes, and the observation holes serving as the overflow holes are not provided with the transparent waterproof tape.

2. The dynamic permeability coefficient measuring device according to claim 1, characterized in that: The water seepage structure includes a support trough body with an opening on the top, the bottom end of the sample storage tube extends into the support trough body through the opening, a drainage layer supported below the liquid outlet is laid in the support trough body, and a drainage port located below the drainage layer is opened on the bottom wall of the support trough body.

3. The dynamic permeability coefficient measuring device according to claim 2, characterized in that: The drainage layer includes a permeable stone layer and a filter cloth layer. The permeable stone layer is laid on the inner bottom of the support trough body and covers the top of the drainage port. The filter cloth layer covers the top surface of the permeable stone layer and is supported below the liquid outlet.

4. The dynamic permeability coefficient measuring device according to claim 3, characterized in that: The permeate supply mechanism comprises a permeate container and an infusion tube, one end of the infusion tube is connected to the permeate container, and the other end is connected to the liquid inlet, and a delivery pump for adjusting the infusion rate is provided on the infusion tube.

5. The dynamic permeability coefficient measuring device according to claim 4, characterized in that: The permeate container is equipped with a support seat, in which a drive motor and a rotating magnet connected to the output shaft of the drive motor are arranged. The permeate container is arranged on the support seat, and in which a magnetic rotor that rotates synchronously with the rotating magnet is arranged.

6. The dynamic permeability coefficient measuring device according to claim 5, characterized in that: The liquid discharge port is connected to a permeate collection container.

7. A measuring system using the dynamic permeability measuring device according to claim 6, characterized in that: It comprises a first porous plate and a second porous plate movably arranged above the first porous plate in a vertical direction, and a plurality of the sample fixing mechanisms are arranged between the first porous plate and the second porous plate; The supporting grooves of each of the sample fixing mechanisms are supported on the first porous plate, and the second porous plate abuts against the top of the sample storage tube of each of the sample fixing mechanisms; A plurality of delivery pipes are connected in parallel to the delivery pump outlet of the permeate supply mechanism, and each of the delivery pipes passes through a through hole on the second porous plate and is connected to the liquid inlet of the corresponding sample storage tube.

8. A measuring method using the measuring system according to claim 7, characterized in that: The steps include: Preparation of permeate: put the permeate used in the test into the permeate container, and drive the magnetic rotor to rotate through the driving motor and the rotating magnet to stir the permeate evenly; Installation of the sample fixing mechanism: a permeable stone layer is laid on the bottom of the inner side of the support trough body and covered above the drainage port, a filter cloth layer is covered on the top surface of the permeable stone layer, the bottom end of the sample storage tube is supported on the top surface of the filter cloth layer, and the liquid level tube is installed at the corresponding overflow hole on the sample storage tube according to the height of the soil sample; Soil sample preparation: filling the air-dried soil sample or pre-treated soil into the sample storage tube and filling it to the required height; Preparation before the permeation test: prepare multiple sets of the sample fixing mechanisms, and install the supporting trough of each of the sample fixing mechanisms on the first porous plate, and overlap the second porous plate on the top of the sample storage tube of each of the sample fixing mechanisms; The liquid outlet end of each delivery tube passes through the through hole on the second porous plate and is connected to the liquid inlet of the corresponding sample storage tube, and the liquid inlet end of each delivery tube is connected to the outlet of the delivery pump; Start the permeation test: inject the permeate into each of the sample storage tubes through the delivery pump, and after the permeation rate stabilizes, control the permeation rate to keep the liquid surface of the permeate tangent to the overflow hole above, and record the running time, the flow rate of the permeate and the volume of the liquid flowing through the soil sample; The water head difference in the two overflow pipes is measured to obtain the real-time water level difference, and then the real-time permeability coefficient of the soil sample is calculated according to the height of the soil sample between the two overflow holes, the cross-sectional area of ​​the soil sample and the flow rate of the permeate.

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