A water permeability testing device and method for self-repairing spraying materials for mining

Abstract

The present invention proposes a water permeability test device and method for self-repairing spray materials for mining. The test device includes a support plate and a water tank, a control valve, a sample fixing device, a liquid level detector, a weighing device, a power switch and a control system arranged on the support plate. The water outlet of the water tank is located below the water tank and connected to the control valve. The sample fixing device is located below the water outlet of the water tank and is connected to a prefabricated sample to be tested, and is provided with a funnel for receiving and transporting seepage water. A useful water receiving container is placed on the weighing device, and the water receiving container is located below the funnel. The liquid level detector is located on one side of the sample fixing device. The sample fixing device is connected to the support plate through a telescopic device, and a sample sealing device is provided on one side. The sample fixing device can be moved to the sample sealing device, and the device is controlled by a control system. The present invention controls the entire test process through a control system, has a high degree of automation, is simple and convenient to operate, has good sealing performance and high measurement and calculation accuracy.

Description

Technical Field

[0001] The invention relates to the technical field of self-repairing spray material performance testing, and in particular to a water permeability testing device and method for a self-repairing spray material for mining. Background Art

[0002] In the process of coal mining, the occurrence of coal spontaneous combustion has become one of the main threats to the normal operation of coal mining. Coal spontaneous combustion can cause a series of serious problems such as mine fires, gas explosions, coal mine shutdowns, and the release of toxic and harmful gases. In order to prevent the occurrence of coal spontaneous combustion, colloids, polymer foam materials, cement-based materials and other air leakage plugging materials are usually sprayed on the surface of closed walls and coal pillars along the air. Among these materials, cement-based materials have been widely used in mine leakage plugging due to their high strength and low cost. However, under the action of mine pressure, cement-based materials are very prone to cracks, forming air leakage channels, which can easily cause coal spontaneous combustion fires. Therefore, the repair of cracks in cement-based materials is crucial.

[0003] In recent years, researchers have developed a self-healing spray material to address the problem of cracks in cement-based materials. This self-healing spray material is made of a healing agent and cement mortar in a certain proportion. Currently, commonly used healing agents include polymer healing agents, mineral healing agents, and microbial healing agents. These healing agents can autonomously identify and repair existing cracks. The self-healing effect of cracks is related to the plugging effect of self-healing materials, and the water permeability of materials is an important indicator of the crack healing effect. Therefore, it is of great significance to test the water permeability of materials after crack healing.

[0004] At present, a water permeability testing device is generally used when conducting a water permeability test on a self-repairing spray material. When conducting the test, first prepare a sample to be tested and measure its diameter, height and water permeable cross-sectional area, then place the sample in the testing device, start the test and record the test time, and finally calculate the water permeability coefficient based on the obtained data. However, existing water permeability testing devices generally have the disadvantages of low automation, difficulty in disassembling the sample to be tested, long time consumption, simple structure, poor sealing, and low measurement accuracy. Therefore, a water permeability testing device and method with high automation, simple operation, good sealing and high measurement accuracy is needed. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the present invention proposes a water permeability testing device for self-repairing spray materials for mining, including a support plate and a water tank, a control valve, a sample fixing device, a liquid level detector, a weighing device, a power switch and a control system arranged on the support plate, the water tank is arranged on the top of the support plate, the water outlet of the water tank is located below the water tank, the water outlet of the water tank is connected to the control valve, the sample fixing device is located below the water outlet of the water tank, the sample fixing device is detachably connected with a prefabricated sample to be tested, a funnel for receiving and transporting seepage water is provided below the sample fixing device, a water receiving container for collecting and storing seepage water is placed on the weighing device, the water receiving container is located below the funnel, the liquid level detector is located on one side of the sample fixing device, and the prefabricated sample to be tested is located within the detection range of the liquid level detector after being placed on the sample fixing device;

[0006] The sample fixing device is connected to the support plate through a telescopic device, and a sample sealing device for preparing a prefabricated sample to be tested is provided next to the sample fixing device. The sample fixing device can be moved to the sample sealing device under the drive of the telescopic device;

[0007] The control system is respectively connected to the control valve, water tank, liquid level detector, weighing device, sample fixing device, telescopic device and sample sealing device, and the power switch is respectively connected to the control system, control valve, water tank, liquid level detector, weighing device, sample fixing device, telescopic device and sample sealing device.

[0008] Preferably, the water tank is connected to the support plate via a water tank support rod;

[0009] A base is provided at the bottom end of the support plate, and a weighing device is arranged on the base; the funnel is connected to the support plate through a funnel bracket.

[0010] Preferably, the water outlet end of the water tank is connected to a water outlet pipe, a control valve is arranged on the water outlet pipe, the water tank also includes a water inlet for water inlet and a liquid level sensor for detecting the water level in the water tank, and the control system is connected to the liquid level sensor in the water tank.

[0011] Preferably, the control system is a computer with a touch screen, in which software capable of automatic calculation is installed, and on the screen there are buttons for controlling the operation of the device such as "spray glue", "wrap", "sample", "prepare", "test" and "result";

[0012] The power switch includes an "ON" button for turning on the power and an "OFF" button for turning off the power.

[0013] Preferably, the sample fixing device comprises a clamp, an inflatable self-compacting rubber pad and a support frame, wherein the clamp comprises two semicircular ring-shaped clamping jaws, one end of the two semicircular ring-shaped clamping jaws are hinged, and a support is fixedly connected to the outer wall of the two semicircular ring-shaped clamping jaws, each clamping jaw is connected to the support frame through a group of connecting rods and a hydraulic telescopic rod, and the two groups of connecting rods and the hydraulic telescopic rods are symmetrically distributed;

[0014] One end of the connecting rod is fixedly connected to the support frame, the other end of the connecting rod is hinged to the support, one end of the support frame is connected to the telescopic device, the other end of the support frame is fixedly connected to the fixed end of the hydraulic telescopic rod, the driving end of the hydraulic telescopic rod is connected to the hinged end of the clamp, and the inflatable self-compacting rubber pad is arranged on the clamping side of the clamp;

[0015] The inflatable self-compacting rubber pad is connected to an air pump for inflation, and the hydraulic telescopic rod and the air pump are connected to a control system.

[0016] Preferably, the prefabricated test sample comprises a plastic plate, a waterproof sealant and a self-repairing material sample, the self-repairing material sample is cylindrical, the plastic plate is coated on the outer side wall of the self-repairing material sample by a sample sealing device, the self-repairing material sample and the plastic plate are sealed and connected by a waterproof sealant, and the waterproof sealant is sprayed by the sample sealing device;

[0017] After the plastic plate covers the self-repairing material sample, it presents a cylindrical structure with upper and lower ends opened, the lower surface of the self-repairing material sample is flush with the bottom end of the cylinder, the top of the cylinder is higher than the upper surface of the self-repairing material sample, and the part of the cylinder higher than the upper surface of the self-repairing material sample is the water storage part;

[0018] The opening diameter of the upper end of the funnel is larger than the diameter of the self-repairing material sample.

[0019] Preferably, the plastic plate is 20-30 cm higher than the upper surface of the self-repairing material sample, the diameter of the self-repairing material sample is 5-15 cm, and the height of the self-repairing material sample is 4-10 cm.

[0020] Preferably, the sample sealing device comprises a prefabricated test sample support platform, a sample sealing platform, and a wrapper, a glue spraying device, a sample clamping device and a baffle arranged on the sample sealing platform;

[0021] The glue spraying device comprises a first hydraulic push rod and a nozzle, the first hydraulic push rod drives the nozzle to move left and right, the sample clamping device comprises a second hydraulic push rod and a first clamping claw, the second hydraulic push rod and the first clamping claw move up and down, there are two wrappers, the two wrappers are slidably arranged on the sample sealing table, the two wrappers (212) are relatively far away from or close to each other in the left and right directions, and the opposite sides of the two wrappers are provided with a semi-coating groove, and after the two wrappers are close to each other and assembled, the two semi-coating grooves form a coating groove that fits the outer wall of the prefabricated sample to be tested;

[0022] The plastic plate is laid between the wrappers, one end of the plastic plate is close to the baffle, the surface of the plastic plate away from the sample sealing table is sprayed with waterproof sealant by a glue spraying device, the self-repairing material sample is placed on the plastic plate sprayed with waterproof sealant, and the lower surface of the self-repairing material sample is close to the baffle;

[0023] The sample support platform is arranged adjacent to the sample sealing platform, and after the prefabricated sample to be tested is manufactured, it is clamped to the prefabricated sample support platform by a clamping hook;

[0024] The control system is respectively connected with the wrapper, the glue spraying device and the sample clamping device in the sample sealing device.

[0025] A method for testing the water permeability of a self-repairing spray material for mining comprises the following steps:

[0026] S1. Sample preparation and curing: Based on the microbial induced calcium carbonate precipitation technology, the self-healing material samples were prepared using biological healing agents and cement mortar. After the preparation, the self-healing material samples were cured;

[0027] S2. Glue spraying: After the curing of the self-repairing material sample is completed, the diameter and height of the self-repairing material sample are measured three times respectively, and the average values ​​of the diameter and height are calculated respectively. Then, the "ON" button on the power switch is pressed to start the equipment. The average values ​​of the diameter and height of the self-repairing material sample and the amount of water used in one test are input into the control system. Then, a plastic plate with a size corresponding to the self-repairing material sample is selected, and the plastic plate is laid flat on the two wrappers on the sample sealing table. One end of the plastic plate is in close contact with the baffle. Click the "glue spraying" button, and the nozzle starts to spray waterproof sealant on the plastic plate. After the glue spraying is completed, the self-repairing material sample is placed flat on the center of the plastic plate, and the lower surface of the self-repairing material sample is in close contact with the baffle.

[0028] S3. Wrapping: Click the "Wrap" button, and the two wrappers move closer to each other, tightly wrap the plastic plate on the outer wall of the self-repairing material sample to form a prefabricated sample to be tested, and then the first clamp clamps the prefabricated sample to be tested to the prefabricated sample to be tested support table, so that the prefabricated sample to be tested stands on the sample to be tested support table;

[0029] S4. Sampling: Click the "Sampling" button, the telescopic device will drive the sample fixing device to move to the support platform of the sample to be tested, and at the same time, the clamp will open and clamp the prefabricated sample to be tested placed on the support platform of the prefabricated sample to be tested. After clamping, the clamp will close, and the telescopic device will return to its original position. At the same time, the air pump will inflate the inflatable self-compacting rubber pad, and the prefabricated sample to be tested will be fastened by the inflated self-compacting rubber pad.

[0030] S5. Prepare: Click the "Prepare" button, and the liquid level sensor checks whether the water in the water tank is sufficient for one test. At the same time, the control system detects whether the liquid level detector, control valve and weighing device can work normally;

[0031] S6, test: click the "test" button, the control system transmits a command to open the control valve, then water flows out of the outlet pipe, and the water flows into the water holding part formed by the plastic plate. After the water flows out, the control valve is closed, and the control system starts timing. At the same time, the liquid level detector detects the initial water level information and transmits it to the control system. Wait until the water level in the plastic plate is constant, and the control system ends timing. The time when timing ends is the test time t. At the same time, the liquid level detector detects the water level information when the water level is constant, and transmits the constant water level information to the control system. The control system calculates the water level difference H according to the initial water level and the constant water level information;

[0032] The water in the water-holding part infiltrates into the funnel through the self-healing material sample, and the infiltrated water enters the water receiving container through the funnel. When the water level is constant, the weighing device will weigh and record the weight of the water in the water receiving container, and transmit the water weight data to the control system. The control system converts the water weight into the water volume Q through calculation;

[0033] S7. Display results: Click the "Results" button, the control system will calculate the water permeability coefficient K according to Darcy's theorem formula, and save the result in the control system for easy viewing. The effect of the material repair can be known based on the obtained water permeability coefficient K. After the test is completed, press the "OFF" button to turn off the test device.

[0034] Preferably, the Darcy's theorem formula is:

[0035]

[0036] Where Q is the amount of water that passes through the self-healing material sample, in ml; L is the height of the sample, in m; A is the area of ​​contact between the self-healing material sample and water, in m 2 ; H is the water level difference before and after the test, unit is m; t is the test time, unit is s; K is the water permeability coefficient, unit is m / s;

[0037] The area of ​​the self-repairing material sample in contact with water is the area of ​​the upper surface of the self-repairing material sample, and the area of ​​the upper surface of the self-repairing material sample is calculated based on the average value of the self-repairing material sample measured in step S2.

[0038] The beneficial effects of the present invention are:

[0039] The present invention conducts testing through the cooperation of a control system and a testing device. During the test, the tester only needs to click a button on the screen to control the entire test process, thereby improving the efficiency and automation of the test and reducing human intervention. At the same time, the test device detects the required data, and the control system receives the data for calculation, thereby reducing human operation errors and ensuring the accuracy of the test results. In addition, the self-repairing material sample can be combined with the plastic plate through a waterproof sealant through a sample sealing device to form a prefabricated sample to be tested, and the clamp can be opened and closed automatically through the control of the control system, and can automatically clamp the prefabricated sample to be tested. The operation is simple and convenient, and the waterproof sealant and inflatable self-compacting rubber pad used make the measuring device have good sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the overall structure of the measuring device of the present invention;

[0041] Figure 2 It is a structural schematic diagram of the sample sealing device of the present invention;

[0042] Figure 3 A top view of the sample sealing device of the present invention;

[0043] Figure 4 It is a front view of the location of the control system of the present invention;

[0044] Figure 5 A top view of the sample testing mechanism of the present invention;

[0045] Figure 6 A three-dimensional diagram of the clamp and the inflatable self-compacting rubber pad of the present invention;

[0046] Figure 7 It is a cross-sectional stereoscopic view of the sample testing mechanism of the present invention.

[0047] Numbers in the figure: 1-base, 2-weighing device, 3-water receiving container, 4-support plate, 5-funnel bracket, 6-funnel, 7-sample fixing device, 71-clamp, 72-inflatable self-compacting rubber pad, 73-support, 74-connecting rod, 75-hydraulic telescopic rod, 76-support frame, 8-prefabricated test sample, 81-plastic plate, 82-waterproof sealant, 83-self-repairing material sample, 9-telescopic device, 10-liquid level detector, 11-control valve, 12-water outlet pipe, 1 3-water tank, 14-water inlet, 15-control system, 16-water tank support rod, 17-air pump, 18-data cable, 19-power switch, 20-air pipe, 21-sample sealing device, 211-sample sealing table, 212-wrapper, 213-glue spraying device, 2131-first hydraulic push rod, 2132-nozzle, 214-sample clamping device, 2141-second hydraulic push rod, 2142-first clamping claw, 215-baffle, 216-prefabricated test sample support table. DETAILED DESCRIPTION

[0048] In order to make the present invention clearer and more understandable, the technical solution of the present invention is further described in detail below in combination with the accompanying drawings and embodiments. It should be understood that the given embodiment is only one implementation method and does not represent all embodiments.

[0049] In this article, the terms "left, right, up, down" and the like are established based on the positional relationships shown in the drawings. Depending on the different drawings, the corresponding positional relationships may also change accordingly. Therefore, they cannot be understood as absolute limitations on the scope of protection.

[0050] Combined with Figure 1-7 , A water permeability testing device for a self-repairing spray material for mining, comprising a support plate 4 and a water tank 13, a control valve 11, a sample fixing device 7, a liquid level detector 10, a weighing device 2, a power switch 19 and a control system 15, wherein the water tank 13 is arranged at the top of the support plate 4, the water outlet end of the water tank 13 is located below the water tank 13, the water outlet end of the water tank 13 is connected to the control valve 11, the sample fixing device 7 is located below the water outlet end of the water tank 13, the sample fixing device 7 is detachably connected with a prefabricated sample to be tested 8, a funnel 6 for receiving and transporting seepage water is provided below the sample fixing device 7, a water receiving container 3 for collecting and storing seepage water is placed on the weighing device 2, the water receiving container 3 is located below the funnel 6, the liquid level detector 10 is located on one side of the sample fixing device 7, and the prefabricated sample to be tested 8 is placed on the sample fixing device 7 and is located within the detection range of the liquid level detector 10;

[0051] The sample fixing device 7 is connected to the support plate 4 through the telescopic device 9. A sample sealing device 21 for preparing a prefabricated sample to be tested is provided next to the sample fixing device 7. The sample fixing device 7 can be moved to the sample sealing device 21 under the drive of the telescopic device 9.

[0052] The control system 15 is connected to the control valve 11, the water tank, the liquid level detector 10, the weighing device 2, the sample fixing device 7, the telescopic device and the sample sealing device 21 respectively through the data line 18, and the power switch 19 is connected to the control system 15, the control valve 11, the water tank, the liquid level detector 10, the weighing device 2, the sample fixing device 7, the telescopic device 9 and the sample sealing device 21 respectively.

[0053] The telescopic device 9 can be a telescopic structure with a power source, such as a telescopic connecting rod driven by a cylinder, and the telescopic device 9 can be telescoped without any specific limitation.

[0054] Preferably, the water tank 13 is connected to the support plate 16 via a water tank support rod 16;

[0055] A base 1 is provided at the bottom end of the support plate 4 , and a weighing device 2 is arranged on the base 1 ; the funnel 6 is connected to the support plate 4 via a funnel bracket 5 .

[0056] Specifically, the water outlet end of the water tank 13 is connected to a water outlet pipe 12, a control valve 11 is arranged on the water outlet pipe 12, the water tank 13 also includes a water inlet 14 for water inlet and a liquid level sensor for detecting the water level in the water tank 13, and the control system 15 is connected to the liquid level sensor in the water tank 13 via a data line 18.

[0057] Specifically, the control system 15 is a computer with a touch screen, in which software capable of automatic calculation is installed, and on the screen there are buttons of "spraying", "wrapping", "sampling", "preparation", "testing" and "result" for controlling the operation of the device;

[0058] The power switch 19 includes an "ON" button for turning on the power and an "OFF" button for turning off the power.

[0059] Specifically, the sample fixing device 7 includes a clamp 71, an inflatable self-compacting rubber pad 72 and a support frame 76. The clamp 71 includes two semicircular ring-shaped clamping jaws, one end of the two semicircular ring-shaped clamping jaws are hinged, and a support 73 is fixedly connected to the outer wall of the two semicircular ring-shaped clamping jaws. Each clamping jaw is connected to the support frame 76 through a group of connecting rods 74 and hydraulic telescopic rods 75. The two groups of connecting rods 74 and hydraulic telescopic rods 75 are symmetrically distributed.

[0060] One end of the connecting rod 74 is fixedly connected to the support frame 76, and the other end of the connecting rod 74 is hinged to the support 73. One end of the supporting frame 76 is connected to the telescopic device 9, and the other end of the supporting frame 76 is fixedly connected to the fixed end of the hydraulic telescopic rod 75. The driving end of the hydraulic telescopic rod 75 is connected to the hinged end of the clamping claw. The inflatable self-compacting rubber pad 72 is arranged on the clamping side of the clamp 71;

[0061] The inflatable self-compacting rubber pad 72 is connected to an air pump 17 for inflation via an air pipe 20 , and the hydraulic telescopic rod 75 and the air pump 17 are connected to a control system 15 via a data line 18 .

[0062] Specifically, the prefabricated test sample 8 includes a plastic plate 81, a waterproof sealant 82 and a self-repairing material sample 83, wherein the self-repairing material sample 83 is cylindrical, and the plastic plate 81 is coated on the outer wall of the self-repairing material sample 83 by a sample sealing device 21, and the self-repairing material sample 83 is connected to the plastic plate 81 by a waterproof sealant seal 82, and the waterproof sealant seal 82 is sprayed by the sample sealing device 21;

[0063] After the plastic plate 81 covers the self-repairing material sample 83, it presents a cylindrical structure with upper and lower ends opened. The lower surface of the self-repairing material sample 83 is flush with the bottom end of the cylinder, and the top of the cylinder is higher than the upper surface of the self-repairing material sample 83. The part of the cylinder higher than the upper surface of the self-repairing material sample 83 is the water storage part.

[0064] The diameter of the opening at the upper end of the funnel 6 is larger than the diameter of the self-repairing material sample 83 .

[0065] Specifically, the plastic plate 81 is 20-30 cm higher than the upper surface of the self-repairing material sample 83, the diameter of the self-repairing material sample 83 is 5-15 cm, and the height of the self-repairing material sample 83 is 4-10 cm.

[0066] Specifically, the sample sealing device 21 includes a prefabricated test sample support platform 216, a sample sealing platform 211, and a wrapper 212, a glue spraying device 213, a sample clamping device 214 and a baffle 215 arranged on the sample sealing platform 211;

[0067] The glue spraying device 213 includes a first hydraulic push rod 2131 and a nozzle 2132, the first hydraulic push rod 2131 drives the nozzle 2132 to move left and right, the sample clamping device 214 includes a second hydraulic push rod 2141 and a first clamping jaw 2142, the second hydraulic push rod 2141 and the first clamping jaw 2142 move up and down, there are two wrappers 212, the two wrappers 212 are slidably arranged on the sample sealing table 211, the two wrappers 212 are relatively far away or close in the left and right directions, and the opposite sides of the two wrappers 212 are provided with a semi-coating groove, and after the two wrappers 212 are close to each other and assembled, the two semi-coating grooves form a coating groove that fits the outer wall of the prefabricated test sample 8;

[0068] The plastic plate 81 is laid between the wrappers 212, one end of the plastic plate 81 is close to the baffle 215, the surface of the plastic plate 81 away from the sample sealing platform 211 is sprayed with waterproof sealant 82 by the glue spraying device 213, and the self-repairing material sample 83 is placed on the plastic plate sprayed with the waterproof sealant 82, and the lower surface of the self-repairing material sample 83 is close to the baffle 215;

[0069] Specifically, the size of one end of the plastic plate 81 close to the baffle 215 is equal to the circumference of the self-repairing material sample 83. This end is the end of the plastic plate 81 that is flush with the lower surface of the self-repairing material sample 83. The purpose of bringing one end of the plastic plate 81 and the lower surface of the self-repairing material sample 83 close to the baffle 215 is to ensure that the two are flush. The area of ​​the plastic plate 81 sprayed with the waterproof sealant 82 is the same as the surface area of ​​the outer wall of the self-repairing material sample 83. From the end of the plastic plate 81 close to the baffle 215 to the direction away from the baffle 215, an area with a distance equal to the height of the self-repairing material sample 83 is selected. This area is the spraying area of ​​the waterproof sealant 82.

[0070] The sample support platform 216 is disposed adjacent to the sample sealing platform 211. After the prefabricated test sample 8 is manufactured, it is clamped to the prefabricated test sample support platform 216 by the clamp hook 2142.

[0071] The control system 15 is connected to the wrapper 212 , the glue spraying device 213 and the sample clamping device 214 in the sample sealing device 21 respectively through the data line 18 .

[0072] A method for testing the water permeability of a self-repairing spray material for mining comprises the following steps:

[0073] S1. Sample preparation and curing: Based on the microbial induced calcium carbonate precipitation technology, a self-healing material sample 83 is prepared using a biological healing agent and cement mortar. After the preparation, the self-healing material sample 83 is cured. The preparation and curing steps are as follows:

[0074] S1.1, Bacterial culture: Select urea-nitrifying bacteria, alkali-resistant Bacillus, Bacillus cereus and other bacteria as target strains. First, place the growth medium containing nutrients in an autoclave and sterilize at 121°C for 30 minutes, then filter a certain amount of potassium nitrate solution and urea solution with a 0.2μm sterile filter and inoculate it into the culture medium, and inoculate the target strain into the culture medium under sterile conditions, then place the culture medium in a constant temperature oscillating box and culture for a period of time, and use a granulator to make the final bacterial spores, nutrients and mineralized substrates into biocapsules;

[0075] S1.2. Preparation of cement base: Cement base materials include ordinary Portland cement, tap water and natural sand;

[0076] S1.3, sample preparation: placing the biocapsule in cement base to prepare cylindrical self-healing material sample 83, the capsule dosage is 5-12% of the cement dosage, the water-cement ratio is 0.45-0.55, and the sand-binder ratio is 2.5-3.5. Finally, the prepared self-healing material sample 83 is placed in a curing box for curing for a certain period of time;

[0077] S1.4. Generation and curing of cracks: After the self-repairing material sample 83 is cured, cracks are generated by splitting and stretching, and the self-repairing material sample 83 is placed in a curing box and cured to a specified age;

[0078] S2, glue spraying: after the self-repairing material sample 83 is cured, the diameter and height of the self-repairing material sample 83 are measured three times, and the average values ​​of the diameter and height are calculated respectively. Then, the "ON" button on the power switch 19 is pressed to start the equipment. The average values ​​of the diameter and height of the self-repairing material sample 83 and the amount of water used for one test are input into the control system 15. Then, a plastic plate 81 having a size corresponding to the self-repairing material sample 83 is selected, and the plastic plate 81 is laid flat on the two wrappers 212 on the sample sealing table 211, with one end of the plastic plate 81 in close contact with the baffle 215. The "glue spraying" button is clicked, and the nozzle 2132 starts to spray the waterproof sealant 82 on the plastic plate 81. After the glue spraying is completed, the self-repairing material sample 83 is placed flat on the center of the plastic plate 81, and the lower surface of the self-repairing material sample 83 is in close contact with the baffle 215.

[0079] S3. Wrap: Click the "Wrap" button, the two wrappers 212 move closer to each other, and tightly wrap the plastic plate 81 on the outer wall of the self-repairing material sample 83 to form a prefabricated test sample 8, and then the first clamp 2142 clamps the prefabricated test sample 8 to the prefabricated test sample support table 216, so that the prefabricated test sample 8 stands on the test sample support table 216;

[0080] S4. Sampling: Click the "Sampling" button, the telescopic device 9 will drive the sample fixing device 7 to move to the test sample support table 216, and at the same time, the clamp 71 opens and clamps the prefabricated test sample 8 placed on the prefabricated test sample support table 216. After clamping, the clamp 71 closes, and the telescopic device 9 returns to the original position. At the same time, the air pump 17 inflates the inflatable self-compacting rubber pad 72, and the inflated inflatable self-compacting rubber pad 72 is used to tighten the prefabricated test sample 8;

[0081] S5. Prepare: Click the "Prepare" button, the liquid level sensor checks whether the water in the water tank 13 is sufficient for one test, and the control system 15 checks whether the liquid level detector 12, the control valve 11 and the weighing device 2 can work normally;

[0082] S6, test: click the "test" button, the control system 15 transmits a command to open the control valve 11, and water flows out of the water outlet pipe 12, and the water flows into the water holding part formed by the plastic plate 81. After the water flows out, the control valve 11 is closed, and the control system 15 starts timing. At the same time, the liquid level detector 10 detects the initial water level information and transmits it to the control system 15. Wait until the water level in the plastic plate 81 is constant, and the control system 15 ends the timing. The time when the timing ends is the test time t. At the same time, the liquid level detector 10 detects the water level information when the water level is constant, and transmits the constant water level information to the control system 15. The control system 15 calculates the water level difference H according to the initial water level and the constant water level information;

[0083] The water in the water-holding part infiltrates into the funnel 6 through the self-repairing material sample 83, and the infiltrated water enters the water receiving container 3 through the funnel 6. When the water level is constant, the weighing device 2 weighs and records the weight of the water in the water receiving container 3, and transmits the water weight data to the control system 15. The control system 15 converts the water weight into the water volume Q through calculation;

[0084] S7. Display results: Click the "Result" button, the control system 15 will calculate the water permeability coefficient K according to the Darcy theorem formula, and save the result in the control system 15 for easy viewing. The effect of the material repair can be known based on the obtained water permeability coefficient K. After the test is completed, press the "OFF" button to turn off the test device.

[0085] Specifically, the Darcy theorem formula is:

[0086]

[0087] Wherein, Q is the amount of water that passes through the self-healing material sample 83, in ml; L is the height of the sample, in m; A is the area of ​​the self-healing material sample 83 in contact with water, in m 2 ; H is the water level difference before and after the test, unit is m; t is the test time, unit is s; K is the water permeability coefficient, unit is m / s;

[0088] The area of ​​the self-repairing material sample 83 in contact with water is the area of ​​the upper surface of the self-repairing material sample 83, and the area of ​​the upper surface of the self-repairing material sample 83 is calculated based on the average value of the self-repairing material sample 83 measured in step S2.

[0089] The above embodiments are only to illustrate the basic principles and characteristics of the present invention, but are not limited to the above embodiments. It should be understood that for ordinary technicians in this field, various changes and modifications can be made to the present invention without departing from the spirit and scope of the present invention, and these changes and modifications fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A water permeability testing device for self-repairing spray materials for mining, characterized in that: The invention comprises a support plate (4), a water tank (13) arranged on the support plate (4), a control valve (11), a sample fixing device (7), a liquid level detector (10), a weighing device (2), a power switch (19) and a control system (15), wherein the water tank (13) is arranged at the top of the support plate (4), a water outlet end of the water tank (13) is located below the water tank (13), the water outlet end of the water tank (13) is connected to the control valve (11), the sample fixing device (7) is located below the water outlet end of the water tank (13), and the sample fixing device (7) is located below the water outlet end of the water tank (13). The sample fixing device (7) is detachably connected to a prefabricated sample to be tested (8); a funnel (6) for receiving and transporting seepage water is provided below the sample fixing device (7); a water receiving container (3) for collecting and storing seepage water is placed on the weighing device (2); the water receiving container (3) is located below the funnel (6); the liquid level detector (10) is located on one side of the sample fixing device (7); and after the prefabricated sample to be tested (8) is placed on the sample fixing device (7), it is located within the detection range of the liquid level detector (10); The sample fixing device (7) is connected to the support plate (4) via a telescopic device (9); a sample sealing device (21) for preparing a prefabricated sample to be tested is provided next to the sample fixing device (7); the sample fixing device (7) can be moved to the sample sealing device (21) under the drive of the telescopic device (9); The control system (15) is respectively connected to the control valve (11), the water tank, the liquid level detector (10), the weighing device (2), the sample fixing device (7), the telescopic device and the sample sealing device (21); and the power switch (19) is respectively connected to the control system (15), the control valve (11), the water tank, the liquid level detector (10), the weighing device (2), the sample fixing device (7), the telescopic device (9) and the sample sealing device (21); The prefabricated test sample (8) comprises a plastic plate (81), a waterproof sealant (82) and a self-repairing material sample (83); the self-repairing material sample (83) is cylindrical; the plastic plate (81) is coated on the outer wall of the self-repairing material sample (83) by a sample sealing device (21); the self-repairing material sample (83) and the plastic plate (81) are connected by a waterproof sealant seal (82); and the waterproof sealant (82) is sprayed by the sample sealing device (21); After the plastic plate (81) covers the self-repairing material sample (83), it presents a cylindrical structure with upper and lower ends opened, the lower surface of the self-repairing material sample (83) is flush with the bottom end of the cylinder, the top of the cylinder is higher than the upper surface of the self-repairing material sample (83), and the portion of the cylinder higher than the upper surface of the self-repairing material sample (83) is a water storage portion; The diameter of the opening at the upper end of the funnel (6) is larger than the diameter of the self-repairing material sample (83); The sample sealing device (21) comprises a prefabricated test sample support platform (216), a sample sealing platform (211), and a wrapper (212), a glue spraying device (213), a sample clamping device (214), and a baffle (215) arranged on the sample sealing platform (211); The glue spraying device (213) comprises a first hydraulic push rod (2131) and a nozzle (2132), the first hydraulic push rod (2131) drives the nozzle (2132) to move left and right, the sample clamping device (214) comprises a second hydraulic push rod (2141) and a first clamping claw (2142), the second hydraulic push rod (2141) and the first clamping claw (2142) move up and down, there are two wrappers (212), the two wrappers (212) are slidably arranged on the sample sealing table (211), the two wrappers (212) are relatively far away from or close to each other in the left and right directions, and semi-coating grooves are provided on opposite sides of the two wrappers (212), and after the two wrappers (212) are close to each other and assembled, the two semi-coating grooves form a coating groove that fits the outer wall of the prefabricated test sample (8); The plastic plate (81) is laid between the wrappers (212), one end of the plastic plate (81) is close to the baffle (215), a surface of the plastic plate (81) away from the sample sealing platform (211) is sprayed with waterproof sealant (82) by a glue spraying device (213), and the self-repairing material sample (83) is placed on the plastic plate sprayed with the waterproof sealant (82), and the lower surface of the self-repairing material sample (83) is close to the baffle (215); The sample support platform (216) is arranged adjacent to the sample sealing platform (211), and after the prefabricated sample to be tested (8) is manufactured, it is clamped onto the prefabricated sample to be tested support platform (216) by the first clamping jaw (2142); The control system (15) is respectively connected to the wrapper (212), the glue spraying device (213) and the sample clamping device (214) in the sample sealing device (21).

2. A water permeability testing device for a self-repairing spray material for mining according to claim 1, characterized in that: The water tank (13) is connected to the support plate (16) via a water tank support rod (16); A base (1) is provided at the bottom end of the support plate (4), and a weighing device (2) is arranged on the base (1); the funnel (6) is connected to the support plate (4) via a funnel bracket (5).

3. The water permeability testing device for a self-repairing spray material for mining according to claim 1 is characterized in that: The water outlet end of the water tank (13) is connected to a water outlet pipe (12), the control valve (11) is arranged on the water outlet pipe (12), the water tank (13) further comprises a water inlet (14) for water inlet and a liquid level sensor for detecting the water level in the water tank (13), and the control system (15) is connected to the liquid level sensor in the water tank (13).

4. The water permeability testing device for a self-repairing spray material for mining according to claim 1 is characterized in that: The control system (15) is a computer with a touch screen, in which software capable of automatic calculation is installed, and on the screen there are buttons for controlling the operation of the device, namely, "spraying", "wrapping", "sampling", "preparation", "testing" and "results"; The power switch (19) comprises an "ON" button for turning on the power and an "OFF" button for turning off the power.

5. The water permeability testing device for a self-repairing spray material for mining according to claim 1 is characterized in that: The sample fixing device (7) comprises a clamp (71), an inflatable self-compacting rubber pad (72) and a support frame (76), wherein the clamp (71) comprises two semicircular ring-shaped clamping jaws, one end of the two semicircular ring-shaped clamping jaws are hinged, and a support (73) is fixedly connected to the outer wall of each of the two semicircular ring-shaped clamping jaws, each clamping jaw is connected to the support frame (76) via a set of connecting rods (74) and a hydraulic telescopic rod (75), and the two sets of connecting rods (74) and the hydraulic telescopic rod (75) are symmetrically distributed; One end of the connecting rod (74) is fixedly connected to the support frame (76), the other end of the connecting rod (74) is hinged to the support (73), one end of the supporting frame (76) is connected to the telescopic device (9), the other end of the supporting frame (76) is fixedly connected to the fixed end of the hydraulic telescopic rod (75), the driving end of the hydraulic telescopic rod (75) is connected to the hinged end of the clamping claw, and the inflatable self-compacting rubber pad (72) is arranged on the clamping side of the clamp (71); The inflatable self-compacting rubber pad (72) is connected to an air pump (17) for inflation, and the hydraulic telescopic rod (75) and the air pump (17) are connected to a control system (15).

6. The water permeability testing device for a self-repairing spray material for mining according to claim 1 is characterized in that: The plastic plate (81) is 20-30 cm higher than the upper surface of the self-repairing material sample (83); the diameter of the self-repairing material sample (83) is 5-15 cm; and the height of the self-repairing material sample (83) is 4-10 cm.

7. A method for testing the water permeability of a self-repairing spray material for use in a mine, implemented based on the water permeability testing device for a self-repairing spray material for use in a mine according to claim 5, characterized in that: The following steps are involved: S1. Sample preparation and curing: Based on the microbial induced calcium carbonate precipitation technology, a self-healing material sample (83) is prepared using a biological healing agent and cement mortar, and after the preparation, the self-healing material sample (83) is cured; S2, glue spraying: after the curing of the self-repairing material sample (83) is completed, the diameter and height of the self-repairing material sample (83) are measured three times respectively, and the average values ​​of the diameter and height are calculated respectively, then the "ON" button on the power switch (19) is pressed to start the equipment, and the average values ​​of the diameter and height of the self-repairing material sample (83) and the amount of water used in one test are input into the control system (15), then a plastic plate (81) having a size corresponding to the self-repairing material sample (83) is selected, and the plastic plate (81) is laid flat on the two wrappers (212) on the sample sealing table (211), one end of the plastic plate (81) is in close contact with the baffle (215), and the "glue spraying" button is clicked, and the nozzle (2132) starts to spray the waterproof sealant (82) on the plastic plate (81). After the glue spraying is completed, the self-repairing material sample (83) is placed flat on the center of the plastic plate (81), and the lower surface of the self-repairing material sample (83) is in close contact with the baffle (215); S3, wrapping: click the "wrap" button, the two wrappers (212) move closer to each other, and tightly wrap the plastic plate (81) on the outer wall of the self-repairing material sample (83) to form a prefabricated sample to be tested (8), and then the first clamping claw (2142) clamps the prefabricated sample to be tested (8) to the prefabricated sample to be tested support table (216), so that the prefabricated sample to be tested (8) is placed upright on the sample to be tested support table (216); S4. Sampling: Click the "sampling" button, the telescopic device (9) will drive the sample fixing device (7) to move to the test sample support platform (216), and at the same time the clamp (71) will open and clamp the prefabricated test sample (8) placed on the prefabricated test sample support platform (216). After clamping, the clamp (71) will close, the telescopic device (9) will return to its original position, and at the same time the air pump (17) will inflate the inflatable self-compacting rubber pad (72), and the inflated inflatable self-compacting rubber pad (72) will be used to fasten the prefabricated test sample (8); S5, preparation: click the "prepare" button, the liquid level sensor checks whether the water volume in the water tank (13) is sufficient for one test, and the control system (15) checks whether the liquid level detector (10), the control valve (11) and the weighing device (2) are working properly; S6, test: click the "test" button, the control system (15) transmits a command to open the control valve (11), then water flows out of the water outlet pipe (12), and the water flows into the water storage portion formed by the plastic plate (81). After the water flows out, the control valve (11) is closed, and the control system (15) starts timing. At the same time, the liquid level detector (10) detects the initial water level information and transmits it to the control system (15). Wait until the water level in the plastic plate (81) is constant, and the control system (15) ends timing. The time when timing ends is the test time t. At the same time, the liquid level detector (10) detects the water level information when the water level is constant, and transmits the constant water level information to the control system (15). The control system (15) calculates the water level difference H based on the initial water level and the constant water level information; The water in the water-holding part infiltrates into the funnel (6) through the self-healing material sample (83), and the infiltrated water enters the water receiving container (3) through the funnel (6). When the water level is constant, the weighing device (2) weighs and records the weight of the water in the water receiving container (3), and transmits the water weight data to the control system (15). The control system (15) converts the water weight into the water volume Q through calculation; S7. Display results: Click the "Result" button, and the control system (15) will calculate the water permeability coefficient K according to the Darcy theorem formula, and save the result in the control system (15) for easy viewing. The effect of the material repair can be known based on the obtained water permeability coefficient K. After the test is completed, press the "OFF" button to turn off the test device.

8. A water permeability testing method for a self-repairing spray material for mining according to claim 7, characterized in that: The Darcy's theorem formula is: Wherein, Q is the amount of water that passes through the self-healing material sample (83), in ml; L is the height of the sample, in m; A is the area of ​​the self-healing material sample (83) in contact with water, in m 2 ; H is the water level difference before and after the test, unit is m; t is the test time, unit is s; K is the water permeability coefficient, unit is m / s; The area of ​​the self-repairing material sample (83) in contact with water is the area of ​​the upper surface of the self-repairing material sample (83), and the area of ​​the upper surface of the self-repairing material sample (83) is calculated based on the average value of the self-repairing material sample (83) measured in step S2.

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