Device and method for testing full-life-cycle retardation performance of grouting consolidation body

Abstract

The invention belongs to the field of environmental geotechnical engineering technology or mining area polluted underground water prevention and control, and particularly relates to a grouting consolidation body full-life-cycle retardation performance testing device and method which are overall simple and easy to implement, and temperature, suction, underground water flow velocity and water chemical environment can be controlled at the same time. The device and the method have the advantages that grouting consolidation body maintenance and full-life-cycle retardation performance testing under actual working conditions are simulated, the maintenance cost is low, and the device and the method have generalizability in actual engineering and have important engineering significance and theoretical research value.

Description

Technical Field

[0001] The present application relates to the field of environmental geotechnical engineering technology or the field of groundwater contamination prevention and control technology in mining areas, and in particular to a device and method for testing the blocking performance of a grouting joint over its entire life cycle. Background Art

[0002] Manganese ore resources are important strategic minerals in my country and are widely used in steel smelting, chemical manufacturing, electronic technology and other fields. However, long-term large-scale manganese mining activities have significantly changed the hydrogeological conditions of the mining area, resulting in a highly developed rock joint and fissure system and a more complex hydrodynamic system. After rainfall infiltrates into the mining area, the rainwater comes into contact with the manganese-containing rock and soil, undergoes chemical leaching, and produces high-concentration manganese ion-contaminated water. These manganese-containing contaminated waters migrate along the joints and fissures and diffuse to the surrounding aquifers through underground runoff, significantly increasing the concentration of manganese ions in the groundwater. The huge amount of mine water and the complex runoff path further aggravate the scope and intensity of pollution, posing a serious threat to the safety of regional groundwater resources and the sustainability of the ecological environment. This environmental risk is particularly prominent in areas where manganese ore resources are concentrated, and it is urgent to formulate scientific and effective pollution prevention and control strategies to curb its adverse effects.

[0003] Among various pollution prevention and control technologies, cement-based composite material grouting plugging technology is widely regarded as an economical and efficient method for treating joint and fissure pollution in manganese mining areas due to its excellent low permeability and high adsorption capacity for heavy metal ions. By plugging fissures by grouting, this technology can effectively prevent the migration and diffusion of manganese ions and reduce the permeability of mine water, thereby protecting groundwater resources. However, during the long-term service of grouting materials, their blocking performance and water plugging ability for heavy metal pollutants will gradually weaken due to multiple factors such as material degradation, chemical environment changes, groundwater level fluctuations, and dry-wet cycles. This performance degradation not only increases the risk of groundwater pollution, but also limits the optimization and large-scale application of this technology. At present, the research on the change mechanism of grouting body performance throughout the life cycle and the systematic evaluation method is still in its initial stage, and it is urgent to carry out in-depth exploration at the theoretical and practical levels to promote the improvement and promotion of technology.

[0004] Permeability and membrane effect are key indicators for measuring the material's ability to block ion migration. They can directly reflect the blocking performance of the grouting joint entity and predict its service life. However, since the formation of the grouting joint entity requires a special maintenance environment and conditions, the traditional sample preparation method is difficult to meet the relevant testing requirements. In addition, although the commonly used clay plate method can be used for unsaturated suction control research, it has problems such as complex operation, limited suction control range and high cost, which further restricts the systematic study of the blocking performance of unsaturated grouting joint entities. Overall, the following problems still exist:

[0005] (1) Currently, there are few studies on the evaluation of the solid blocking performance of grouting junctions, and there are few reports on the research on the solid membrane effect of grouting junctions. There is no device for testing the solid membrane effect of grouting junctions.

[0006] (2) There is no instrument that integrates both permeability and membrane effect testing functions;

[0007] (3) Some scholars have developed a saturated clay film effect test device, but there is no mature unsaturated film effect test device;

[0008] (4) Related research uses clay plates to control suction to achieve an unsaturated state, which has the disadvantages of cumbersome experimental operation, long time consumption, limited suction control range, and high equipment cost;

[0009] (5) The curing of the structure needs to be carried out in a specific environment. The existing membrane effect test equipment is generally large in size and is not convenient for curing in a curing box;

[0010] (6) The state (strength, volume, blocking performance, etc.) of the structure will change during the maintenance process and service process, and there is a lack of equipment that can test the membrane effect of the structure throughout its life cycle.

[0011] In summary, the development of a set of grouting joint entity blocking performance test equipment and methods that are easy to operate, highly efficient, have a wide range of suction control, and are economical and applicable has important scientific value and engineering significance. This research can not only provide a scientific basis for the full life cycle evaluation of the blocking performance and water plugging capacity of grouting joint entities, but also provide a theoretical basis and practical guidance for environmental pollution prevention and control and resource protection in manganese mining areas and even other mining areas, thereby promoting the innovation and sustainable development of mining ecological environment governance technology. Summary of the invention

[0012] The embodiment of the present application provides a device and method for testing the blocking performance of a grouting junction throughout its life cycle. The device and method are simple and easy to use overall, can economically and efficiently test the membrane effect of a grouting junction, and can evaluate its blocking performance and water plugging performance throughout its life cycle. The device and method have low maintenance costs, are applicable in actual projects, and have important engineering significance and theoretical research value.

[0013] To this end, according to one aspect of the present application, a device for testing the blocking performance of a grouting joint entity throughout its life cycle is provided, comprising:

[0014] The integrated test chamber for maintenance test comprises a rigid cylinder, a base, a connection assembly and an upper sealing body, wherein the base is detachably arranged at the bottom of the rigid cylinder through the connection assembly, the upper sealing body is slidingly and sealingly arranged in the rigid cylinder, and the base, the interior of the rigid cylinder and the upper sealing body are surrounded to form a containing cavity for containing paste grouting material; the inner wall of the rigid cylinder is embedded with an annular permeable stone, and the top of the base and the bottom of the upper sealing body are both embedded with permeable stones;

[0015] A gas phase suction control component is connected to two opposite sides of the annular permeable stone and controls the suction of the sample in the accommodating cavity by a gas phase method;

[0016] A temperature control component, used to control the internal temperature of the accommodating cavity;

[0017] The permeation assembly comprises a liquid storage container and a liquid collecting container, wherein the bottom of the base is provided with a water inlet connected to the permeable stone thereon, the top of the upper sealing body is provided with a water outlet connected to the permeable stone thereon, the bottom of the liquid storage container is connected to the water inlet through a water inlet pipe, a valve is provided on the water inlet pipe, the water outlet is connected to the liquid collecting container through a water outlet pipe, and the position of the liquid storage container is higher than the position of the liquid collecting container;

[0018] A solution circulation device, comprising two sets of solution circulation components, wherein the solution circulation components comprise a supply bottle for providing injection liquid, a liquid inlet peristaltic pump connected to the supply bottle via a liquid inlet pipe, a collection bottle for collecting liquid, and a liquid outlet peristaltic pump connected to the collection bottle via a liquid outlet pipe, wherein the liquid inlet pipe and the liquid outlet pipe in one set of the solution circulation components are in communication with the permeable stone on the base; and the liquid inlet pipe and the liquid outlet pipe in the other set of the solution circulation components are in communication with the permeable stone on the upper sealing body; and

[0019] The differential pressure monitoring assembly is used to monitor the chemical osmotic pressure difference between the top and bottom ends of the sample.

[0020] According to another aspect of the present application, a method for testing the blocking performance of a grouting junction entity throughout its life cycle is provided. Based on the device for testing the blocking performance of a grouting junction entity throughout its life cycle as described above, the method for testing the blocking performance of a grouting junction entity throughout its life cycle comprises the following steps:

[0021] S1. Sample preparation: Prepare paste grouting materials according to design requirements;

[0022] S2. Sample loading: Loading the sample in the integrated test chamber for curing and testing;

[0023] S3. Simulating actual maintenance conditions: adjusting the temperature control component according to the temperature environment of the actual site to simulate the temperature conditions of the site; injecting a certain concentration of salt solution into the supply bottles of the two sets of the solution circulation components according to the water chemical environment of the actual site to simulate the groundwater conditions of the site; setting the flow rates of the inlet peristaltic pump and the outlet peristaltic pump in the two sets of the solution circulation components according to the groundwater flow rate of the actual site to simulate the groundwater flow rate of the site; finally, preparing the saturated solution in the gas phase suction control component according to the unsaturated state of the actual site to simulate the unsaturated maintenance conditions;

[0024] S4. Sample curing: Under the curing conditions set in step S3, curing for a certain number of days to complete the sample curing;

[0025] S5. Cleaning the solid: After the curing is completed, close the two sets of the solution circulation components and the gas phase suction control component, replace the solution in the supply bottle of the two sets of the solution circulation components with distilled water, adjust the flow rate of the inlet peristaltic pump and the outlet peristaltic pump, and continuously measure the conductivity of the liquid in the collection bottle. When the conductivity is less than half of the conductivity of the salt solution used in the supply bottle of the solution circulation component in step S3, the cleaning of the solid is considered to be completed;

[0026] S6. Conduct a penetration test using the penetration component;

[0027] S7. Conduct membrane effect test under saturated / unsaturated state;

[0028] S8. Take out the knot and divide it into three parts. Use the filter paper method to test the suction of each part of the knot. Take the average value and record it as the actual suction s s ;

[0029] S9. Change the test conditions, repeat the above test steps, and carry out the grouting joint entity blocking performance test under different working conditions;

[0030] S10. Draw the relationship curve between curing time, actual suction, permeability coefficient and membrane efficiency coefficient to comprehensively evaluate and predict the blocking performance of the grouting joint.

[0031] The device and method for testing the blocking performance of a grouting joint throughout its life cycle provided by the present application have at least the following beneficial effects:

[0032] (1) The test device uses the gas phase method to control the suction. Compared with the existing device that uses clay plates to control the suction, the suction loading speed is fast and the suction control range is wide, which realizes the test of the unsaturated membrane effect of the grouting structure in a wide suction range. In addition, the instrument and equipment are simple in composition, easy to operate, low in cost, small in space occupation, and have great value for wide promotion and application;

[0033] (2) The test device includes a gas phase suction control component, an integrated test chamber for curing and testing, and two sets of solution circulation components. Different curing conditions can be controlled according to the actual conditions on site, achieving unsaturated condition control, flow rate control, temperature control, and chemical environment control, which greatly restores the actual curing conditions and ensures the practicality of the test results.

[0034] (3) In view of the phase change characteristics (from paste to solid phase) of grouting materials during curing, a special sample filling method is proposed, so that test curing, saturated / unsaturated permeability test and membrane effect test can be completed in the same test chamber, which is simple to operate, improves test efficiency and saves costs;

[0035] (4) A method for evaluating the blocking performance of grouting structures over their entire life cycle was proposed. Compared with the traditional evaluation method, this method comprehensively considered the permeability, suction and membrane effect of the grouting structures, and also introduced a time variable. By setting different curing times and controlling different curing environments, the blocking performance (suction, membrane effect and permeability) of the grouting structures over their entire life cycle under various working conditions was evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] in:

[0038] Figure 1 It is a schematic diagram of the overall structure of a device for testing the blocking performance of a grouting joint entity throughout its life cycle, as shown in one embodiment of the present application;

[0039] Figure 2 It is a schematic diagram of the sample loading process of the integrated test chamber for maintenance and testing in a grouting joint entity full life cycle blocking performance testing device shown in one embodiment of the present application;

[0040] Figure 3 is a test result diagram of the whole life cycle blocking performance test method of the grouting joint entity shown in an embodiment of the present application, wherein ω is the membrane efficiency coefficient, t is the curing time, k is the permeability coefficient, s is the loading suction, s s is the actual suction force;

[0041] Figure 4 It is a flow chart of the steps of using a grouting joint entity full life cycle blocking performance test method to simulate blocking performance testing under extreme working conditions, shown in one embodiment of the present application.

[0042] Description of main component symbols:

[0043] 10. Rigid cylinder; 11. Base; 12. Connecting assembly; 13. Upper sealing body; 14. Annular permeable stone; 15. Permeable stone; 1. Gas circulation pump; 2. First liquid storage tank; 3. Second liquid storage tank; 4. Pipeline; 5. CNC display screen; 6. Temperature sensor; 7. Heating belt; 8. Liquid storage container; 9. Liquid collecting container; 20. Pressure difference sensor; 21. Data acquisition instrument; 22. Supply bottle; 23. Liquid inlet peristaltic pump; 24. Collecting bottle; 25. Liquid outlet peristaltic pump; 30. Filter paper; 31. Inverted "T" shaped top cover; 32. Sample. DETAILED DESCRIPTION

[0044] In order to facilitate the understanding of the present application, the present application will be described more comprehensively with reference to the relevant drawings below. The preferred embodiments of the present application are provided in the drawings. However, the present application can be implemented in many other different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0045] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0046] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0048] According to one aspect of the present application, an embodiment of the present application provides a device for testing the blocking performance of a grouting joint entity throughout its life cycle, such as Figure 1 As shown, it includes an integrated test chamber for maintenance and testing, a gas phase suction control component, a temperature control component, a permeation component, a solution circulation device and a pressure difference monitoring component.

[0049] The integrated test chamber for curing and testing includes a rigid cylinder 10, a base 11, a connecting assembly 12 and an upper sealing body 13. The base 11 is detachably arranged at the bottom of the rigid cylinder 10 through the connecting assembly 12. The upper sealing body 13 is slidingly and sealingly arranged in the rigid cylinder 10. The base 11, the interior of the rigid cylinder 10 and the upper sealing body 13 are surrounded to form a containing cavity for containing paste grouting materials. An annular permeable stone 14 is embedded in the inner wall of the rigid cylinder 10, and permeable stones 15 are embedded in the top of the base 11 and the bottom of the upper sealing body 13. The gas phase suction control assembly is connected to the opposite sides of the annular permeable stone 14, and the suction of the sample 32 in the containing cavity is controlled by the gas phase method. The temperature control assembly is used to control the internal temperature of the containing cavity. The infiltration assembly includes a liquid storage container 8 (such as a tap bottle) and a liquid collection container 9 (such as a measuring cylinder). The bottom of the base 11 is provided with a water inlet connected to the permeable stone 15 thereon, and the top of the upper sealing body 13 is provided with a water outlet connected to the permeable stone 15 thereon. The bottom of the liquid storage container 8 is connected to the water inlet through a water inlet pipe, and the water inlet pipe is provided with a valve. The water outlet is connected to the liquid collection container 9 through a water outlet pipe. The position of the liquid storage container 8 is higher than that of the liquid collection container 9. The solution circulation device includes two sets of solution circulation assemblies, which include a supply bottle 22 for providing injection liquid, a liquid inlet peristaltic pump 23 connected to the supply bottle 22 through a liquid inlet pipe, a collection bottle 24 for collecting liquid, and a liquid outlet peristaltic pump 25 connected to the collection bottle 24 through a liquid outlet pipe. The liquid inlet pipe and the liquid outlet pipe in one set of the solution circulation assemblies are connected to the permeable stone 15 on the base 11; the liquid inlet pipe and the liquid outlet pipe in the other set of the solution circulation assemblies are connected to the permeable stone 15 on the upper sealing body 13. The differential pressure monitoring assembly is used to monitor the chemical osmotic pressure difference between the top and bottom ends of the sample 32 .

[0050] In the embodiment of the present application, the device for testing the blocking performance of the grouting joint entity throughout its life cycle adopts the gas phase method to control the suction. Compared with the existing device that uses clay plates to control the suction, the suction loading speed is fast and the suction control range is wide, thereby realizing the unsaturated membrane effect test of the grouting joint entity within a wide suction range. The instrument and equipment are simple in composition, easy to operate, low in cost, small in space occupation, and have great value for wide promotion and application. The test device includes a gas phase suction control component, an integrated test chamber for maintenance and testing, and two sets of solution circulation components, which can control different maintenance conditions according to the actual conditions on site, realize unsaturated condition control, flow rate control, temperature control, and chemical environment control, and restore the actual maintenance conditions to a great extent, thereby ensuring the practicality of the test results.

[0051] In addition, the use of the grouting joint entity full life cycle blocking performance test device for testing is generally simple and easy. It can simultaneously control the temperature, suction, groundwater flow rate, and water chemical environment, and realize the grouting joint entity maintenance and full life cycle blocking performance testing under simulated actual working conditions. At the same time, it has low maintenance costs and is applicable in actual projects. It has important engineering significance and theoretical research value.

[0052] Among them, the inner wall of the annular permeable stone 14 is flush with the inner wall of the rigid cylinder 10; the height of the annular permeable stone 14 is not less than one-third of the height of the rigid cylinder 10 and does not exceed one-half of the height of the rigid cylinder 10. During the test, the annular permeable stone 14 does not contact the base 11 and the permeable stone 15 on the upper sealing body 13.

[0053] In one embodiment, if Figure 1 As shown, the gas phase suction control component includes a gas circulation pump 1, a first liquid storage tank 2, a second liquid storage tank 3 and a valve. The outer wall of the rigid cylinder 10 is relatively provided with an air inlet and an air outlet, and the air inlet and the air outlet are both connected with the annular permeable stone 14. The first liquid storage tank 2 is filled with a saturated salt solution, and the air outlet end of the gas circulation pump 1 is passed into the saturated salt solution. The first liquid storage tank 2, the second liquid storage tank 3 and the air inlet are connected in turn through a pipeline 4, and the air outlet is connected to the air inlet end of the gas circulation pump 1 through a pipeline 4, and the valve is arranged on the pipeline 4.

[0054] It can be understood that by filling different saturated salt solutions in the first liquid storage tank 2, different suction controls can be achieved, such as the suction corresponding to the saturated K2SO4 solution is 4.2MPa, and the suction corresponding to the saturated ZnS04 solution is 12.6MPa.

[0055] In one embodiment, if Figure 1 As shown, the temperature control component includes a CNC display screen 5 and a heating belt 7 and a temperature sensor 6 electrically connected to the CNC display screen 5. The heating belt 7 is evenly wound on the outer wall of the rigid cylinder 10, and the temperature sensor 6 is embedded in the permeable stone 15 on the upper sealing body 13. The CNC display screen 5 is used to set the heating temperature of the heating belt 7 as needed, and the temperature sensor 6 is used to detect the internal temperature of the accommodating cavity.

[0056] In one embodiment, if Figure 1 As shown, the differential pressure monitoring assembly includes a data acquisition instrument 21 and two differential pressure sensors 20 electrically connected to the data acquisition instrument 21 . The two differential pressure sensors 20 are respectively disposed in the permeable stone 15 on the base 11 and in the permeable stone 15 on the upper sealing body 13 .

[0057] According to another aspect of the present application, an embodiment of the present application further provides a method for testing the blocking performance of a grouting junction entity throughout its life cycle. Based on the device for testing the blocking performance of a grouting junction entity throughout its life cycle provided by the present application, the method for testing the blocking performance of a grouting junction entity throughout its life cycle comprises the following steps:

[0058] S1. Sample preparation: Prepare the paste grouting material according to the design requirements. Specifically, mix the various components of the composite grouting material and distilled water in a certain proportion and stir them evenly into a paste;

[0059] S2. Sample loading: Loading sample 32 in the integrated test chamber for curing and testing;

[0060] S3. Simulating actual maintenance conditions: According to the temperature environment of the actual site, adjust the temperature control component to simulate the temperature conditions of the site; according to the water chemical environment of the actual site, inject a certain concentration of salt solution into the supply bottle 22 of the two sets of solution circulation components to simulate the groundwater conditions of the site, and according to the groundwater flow rate of the actual site, set the flow rate of the inlet peristaltic pump 23 and the outlet peristaltic pump 25 in the two sets of solution circulation components to simulate the groundwater flow rate of the site; finally, according to the unsaturated state of the actual site, prepare the saturated solution in the gas phase suction control component to simulate the unsaturated maintenance conditions;

[0061] S4. Sample curing: Under the curing conditions set in step S3, curing for a certain number of days to complete the sample curing;

[0062] S5. Cleaning the solid: After the curing is completed, close the two sets of solution circulation components and the gas phase suction control component, replace the solution in the supply bottle 22 of the two sets of solution circulation components with distilled water, adjust the flow rate of the inlet peristaltic pump 23 and the outlet peristaltic pump 25, and continuously measure the conductivity of the liquid in the collection bottle 24. When the conductivity is less than half of the conductivity of the salt solution used in the supply bottle 22 of the solution circulation component in step S3, it is considered that the cleaning of the solid is completed;

[0063] S6. Conduct penetration tests using penetration components;

[0064] S7. Conduct membrane effect test under saturated / unsaturated state;

[0065] S8. Take out the knot and divide it into three parts. Use the filter paper method to test the suction of each part of the knot. Take the average value and record it as the actual suction s s ;

[0066] S9. Change the test conditions, repeat the above test steps, and carry out the grouting joint entity blocking performance test under different working conditions;

[0067] S10. Draw the relationship curve between curing time, actual suction, permeability coefficient and membrane efficiency coefficient, such as Figure 3 As shown, the blocking performance of the grouting structure is comprehensively evaluated and predicted.

[0068] In the embodiments of the present application, the method for testing the blocking performance of the grouting joint entity throughout its life cycle targets the phase change characteristics (from paste to solid phase) that occur during the curing process of the grouting material, so that test curing, saturated / unsaturated permeability test and membrane effect test can all be completed in the same test chamber, which is simple to operate, improves test efficiency and saves costs. The method is simple and easy to implement as a whole, and can simultaneously control temperature, suction, groundwater flow rate and water chemical environment, thereby realizing the curing of the grouting joint entity and the blocking performance test throughout its life cycle under simulated actual working conditions. At the same time, it has low maintenance costs and is applicable to actual projects, and has important engineering significance and theoretical research value.

[0069] Compared with traditional evaluation methods, this method comprehensively considers the permeability, suction and membrane effect of the grouting structure, and also introduces the time variable. By setting different curing times and controlling different curing environments, the blocking performance (suction, membrane effect and permeability) of the grouting structure over the entire life cycle under various working conditions is realized.

[0070] In one embodiment, in combination Figure 2 As shown, in step S2, loading the sample 32 in the integrated maintenance and testing chamber specifically includes:

[0071] The upper sealing body 13 is installed into the rigid cylinder 10, and the rigid cylinder 10 and the upper sealing body 13 are inverted together, and an inverted "T"-shaped top cover 31 with a specific height is inserted from the bottom of the rigid cylinder 10 to keep the upper sealing body 13 stationary in the rigid cylinder 10; filter paper 30 of corresponding size is placed on the surface of the permeable stone 15 on the upper sealing body 13, and then the paste grouting material prepared in advance is filled into the rigid cylinder 10 in multiple layers, and is continuously tamped with a tool (such as a glass rod) to expel bubbles; then, the upper surface of the paste grouting material is scraped flat with a scraper, and the filter paper 30 is placed on it, and then the base 11 is inverted on the rigid cylinder 10 and fastened by a connecting assembly 12 (such as a bolt assembly), and finally the entire integrated maintenance test chamber is quickly turned back to the normal state.

[0072] By adopting the above-mentioned "inverted filling method", the paste grouting material can be filled more densely, ensuring the reliability of subsequent maintenance and testing.

[0073] Embodiment 1:

[0074] The grouting paste materials are mixed in a certain proportion and stirred evenly. Figure 2 Fill the sample into the integrated test chamber for curing and testing using the filling method shown, and ensure that the sample is filled tightly.

[0075] After filling, follow Figure 1 As shown, all parts of the device are connected completely. Distilled water is injected into the supply bottles 22 of the two sets of solution circulation components, the inlet peristaltic pump 23 and the outlet peristaltic pump 25 are started and the flow rate is adjusted to 25.2 μL / min, and the temperature control component is adjusted to set the temperature to 20°C. Under this condition, it is left to stand for curing for 7 days.

[0076] After the curing is completed, the peristaltic pumps in the two sets of solution circulation components are closed, the valve on the water inlet pipe of the permeation component is opened, and the liquid in the liquid storage container 8 flows into the water inlet on the base 11 through the water inlet pipe. The temperature is kept constant at 20°C, and a permeation test is carried out. The water output at different times is recorded using the liquid collecting container 9, and the permeability coefficient is calculated using the following formula, which is to simulate the permeability of the grouting structure under static water and normal temperature curing conditions.

[0077]

[0078] Among them, ΔQ is the flow difference of the seepage fluid at the top and bottom of the structure within Δt time, A is the cross-sectional area of ​​the structure perpendicular to the water flow direction, and I is the hydraulic slope.

[0079] Embodiment 2:

[0080] The grouting paste materials are mixed in a certain proportion and stirred evenly. Figure 2 Fill the sample into the integrated test chamber for curing and testing using the filling method shown, and ensure that the sample is filled tightly.

[0081] After filling, follow Figure 1 As shown, all parts of the device are connected completely. Distilled water is injected into the supply bottles 22 of the two sets of solution circulation components, the inlet peristaltic pump 23 and the outlet peristaltic pump 25 are started and the flow rate is adjusted to 25.2 μL / min, and the temperature control component is adjusted to set the temperature to 20°C. Under this condition, it is left to stand for curing for 7 days.

[0082] After the curing is completed, the distilled water in the supply bottle 22 in the solution circulation assembly connected to the permeable stone 15 on the upper sealing body 13 is replaced with a 10mM manganese sulfate solution, the pressure difference monitoring assembly is turned on, the inlet peristaltic pump 23 and the outlet peristaltic pump 25 are started and the flow rate is adjusted to 25.2μL / min, and the solution is circulated at the top and bottom ends of the structure. During the test, the exudate at the top and bottom ends is collected, and the conductivity and concentration changes of the exudate are measured. After the reading of the pressure difference monitoring assembly is stable, it is considered that the test has reached the stable stage under the action of the 10mM manganese sulfate solution.

[0083] After that, the manganese sulfate solution with higher concentration (20mM, 30mM, 40mM, 50mM) was replaced in turn until the pressure difference value under the last concentration condition was stable, and the test was ended to complete the determination of the efficiency coefficient of the grouting junction under normal curing and saturation state. The membrane effect coefficient was calculated using the following formula. That is, it simulates the grouting junction solid membrane effect under static water and normal temperature curing conditions.

[0084]

[0085] Where Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by the Van't Hoff formula Δπ = vRTΔC, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the junction, v is the total number of ions contained in the electrolyte chemical formula, and R is the universal gas constant (8.314 J·mol -1 ·K -1 ), T is the absolute temperature, and ΔC is the chemical concentration difference between the top and bottom of the structure.

[0086] The range of membrane efficiency coefficient is 0<ω<1. ω=1, indicating that no solute passes through; ω=0, indicating that all solutes can pass through.

[0087] Embodiment 3:

[0088] The grouting paste materials are mixed in a certain proportion and stirred evenly. Figure 2 Fill the sample into the integrated test chamber for curing and testing using the filling method shown, and ensure that the sample is filled tightly.

[0089] After filling, follow Figure 1 As shown, all parts of the device are connected completely. Distilled water is injected into the supply bottles 22 of the two sets of solution circulation components, the inlet peristaltic pump 23 and the outlet peristaltic pump 25 are started and the flow rate is adjusted to 25.2 μL / min, and the temperature control component is adjusted to set the temperature to 20°C. Under this condition, it is left to stand for curing for 14 days.

[0090] After the maintenance is completed, the distilled water in the supply bottle 22 in the solution circulation assembly connected to the permeable stone 15 on the upper sealing body 13 is replaced with a 10mM manganese sulfate solution, the pressure difference monitoring assembly and the gas phase suction control assembly are turned on, the suction is controlled to be 4.2MPa, the liquid inlet peristaltic pump 23 and the liquid outlet peristaltic pump 25 are started and the flow rate is adjusted to 25.2μL / min, and the solution is circulated at the top and bottom ends of the structure.

[0091] During the test, the seepage liquid at the top and bottom ends was collected, and the conductivity and concentration changes of the seepage liquid were measured. When the indication of the differential pressure monitoring component is stable, it is considered that the test has reached the stable stage under the action of 10mM manganese sulfate solution. After that, a higher concentration (20mM, 30mM, 40mM, 50mM) of manganese sulfate solution was replaced until the differential pressure value under the last concentration condition was stable, and the unsaturated grouting solid membrane efficiency test was ended. Open the integrated test chamber for maintenance and testing, take out the solid body, divide it into three parts, and use the filter paper method to test the suction of each part of the solid body. Take the average value and record it as the actual suction s s .

[0092] Repeat the above test steps to complete the grouting structure solid membrane effect test under 38MPa suction state.

[0093] The membrane efficiency coefficient is calculated using the following formula: It is the effect of the solid membrane of the grouting structure at 14 days of age under simulated unsaturated room temperature conditions.

[0094]

[0095] Where Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by the Van't Hoff formula Δπ = vRTΔC, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the junction, v is the total number of ions contained in the electrolyte chemical formula, and R is the universal gas constant (8.314 J·mol -1 ·K -1 ), T is the absolute temperature, and ΔC is the chemical concentration difference between the top and bottom of the structure.

[0096] Embodiment 4:

[0097] like Figure 4 As shown, the grouting paste materials mixed in a certain proportion and stirred evenly are Figure 2 Fill the sample into the integrated test chamber for curing and testing using the filling method shown, and ensure that the sample is filled tightly.

[0098] After filling, follow Figure 1 As shown, all parts of the device are connected completely. Sodium chloride solution is injected into the supply bottles 22 of the two sets of solution circulation components, the inlet peristaltic pump 23 and the outlet peristaltic pump 25 are started and the flow rate is adjusted to 100 μL / min, and the temperature control component is adjusted to set the temperature to 10°C. The pressure difference monitoring component and the gas phase suction control component are turned on, and the suction is controlled to 4.2 MPa. Under this condition, it is left to stand for curing for 90 days.

[0099] After the curing is completed, the peristaltic pumps and gas phase suction control components in the two sets of solution circulation components are turned off, the solutions in the supply bottles 22 of the two sets of solution circulation components are replaced with distilled water, the peristaltic pumps are started and the flow rate is adjusted to 100 μL / min, and the conductivity of the outflowing liquid is continuously measured. When the conductivity value is lower than half of the conductivity value of the 10 mM manganese sulfate solution selected for the test, it is considered that the cleaning of the solid body is completed.

[0100] Afterwards, the valve on the water inlet pipe of the permeation component is opened, the temperature condition is set unchanged, the permeation test is carried out, the water output of the liquid collecting container 9 at different times is recorded, and the permeability coefficient is calculated using the formula in Example 1.

[0101] Afterwards, the gas phase suction control component was started to conduct a solid membrane effect test of the unsaturated grouting structure under the infiltration state of 10 mM manganese sulfate solution, and the membrane effect coefficient was calculated using the following formula.

[0102]

[0103] Among them, Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by the Van't Hoff formula, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the structure, and s is the loading suction.

[0104] After the differential pressure monitoring component readings stabilize, it reaches the stable stage under the action of 10mM manganese sulfate solution. After that, replace the manganese sulfate solution with a higher concentration (20mM, 30mM, 40mM, 50mM) until the differential pressure value under the last concentration condition is stable, and then end the test. Take out the knot body, divide it into three parts, test the suction of each knot body, take the average value, and record it as the actual suction s s That is, the permeability and membrane effect are comprehensively considered to evaluate the solid blocking performance of the grouting structure after 90 days of curing under extreme working conditions.

[0105]

[0106] Where Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by the Van't Hoff formula, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the structure, s s For actual suction.

[0107] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A device for testing the blocking performance of a grouting joint throughout its life cycle, characterized in that: include: The integrated test chamber for maintenance test comprises a rigid cylinder, a base, a connection assembly and an upper sealing body, wherein the base is detachably arranged at the bottom of the rigid cylinder through the connection assembly, the upper sealing body is slidingly and sealingly arranged in the rigid cylinder, and the base, the interior of the rigid cylinder and the upper sealing body are surrounded to form a containing cavity for containing paste grouting material; the inner wall of the rigid cylinder is embedded with an annular permeable stone, and the top of the base and the bottom of the upper sealing body are both embedded with permeable stones; A gas phase suction control component is connected to two opposite sides of the annular permeable stone and controls the suction of the sample in the accommodating cavity by a gas phase method; A temperature control component, used to control the internal temperature of the accommodating cavity; The permeation assembly comprises a liquid storage container and a liquid collecting container, wherein the bottom of the base is provided with a water inlet connected to the permeable stone thereon, the top of the upper sealing body is provided with a water outlet connected to the permeable stone thereon, the bottom of the liquid storage container is connected to the water inlet through a water inlet pipe, a valve is provided on the water inlet pipe, the water outlet is connected to the liquid collecting container through a water outlet pipe, and the position of the liquid storage container is higher than the position of the liquid collecting container; A solution circulation device, comprising two sets of solution circulation components, wherein the solution circulation components comprise a supply bottle for providing injection liquid, a liquid inlet peristaltic pump connected to the supply bottle via a liquid inlet pipe, a collection bottle for collecting liquid, and a liquid outlet peristaltic pump connected to the collection bottle via a liquid outlet pipe, wherein the liquid inlet pipe and the liquid outlet pipe in one set of the solution circulation components are in communication with the permeable stone on the base; and the liquid inlet pipe and the liquid outlet pipe in the other set of the solution circulation components are in communication with the permeable stone on the upper sealing body; and The differential pressure monitoring assembly is used to monitor the chemical osmotic pressure difference between the top and bottom ends of the sample.

2. The device for testing the blocking performance of a grouting joint during its entire life cycle according to claim 1 is characterized in that: The gas phase suction control component includes a gas circulation pump, a first liquid storage tank, a second liquid storage tank and a valve. The outer wall of the rigid cylinder is relatively provided with an air inlet and an air outlet. The air inlet and the air outlet are both connected with the annular permeable stone. The first liquid storage tank is filled with a saturated salt solution. The air outlet end of the gas circulation pump is introduced into the saturated salt solution. The first liquid storage tank, the second liquid storage tank and the air inlet are connected in sequence through a pipeline. The air outlet is connected to the air inlet end of the gas circulation pump through a pipeline, and the valve is arranged on the pipeline.

3. The device for testing the blocking performance of a grouting joint during its entire life cycle according to claim 1 is characterized in that: The inner side wall of the annular permeable stone is flush with the inner wall of the rigid cylinder; the height of the annular permeable stone is not less than one third of the height of the rigid cylinder and does not exceed one half of the height of the rigid cylinder. During the test, the annular permeable stone does not contact the base and the permeable stones on the upper sealing body.

4. The device for testing the blocking performance of a grouting joint during its entire life cycle according to claim 1 is characterized in that: The temperature control component includes a numerical control display screen and a heating belt and a temperature sensor electrically connected to the numerical control display screen. The heating belt is evenly wound around the outer wall of the rigid cylinder. The temperature sensor is embedded in the permeable stone of the upper sealing body. The numerical control display screen is used to set the heating temperature of the heating belt as needed, and the temperature sensor is used to detect the internal temperature of the accommodating cavity.

5. The device for testing the blocking performance of a grouting joint during its entire life cycle according to claim 1 is characterized in that: The pressure difference monitoring assembly includes a data acquisition instrument and two pressure difference sensors electrically connected to the data acquisition instrument. The two pressure difference sensors are respectively arranged in the permeable stone on the base and the permeable stone on the upper sealing body.

6. A method for testing the blocking performance of a grouting joint entity throughout its life cycle, based on the device for testing the blocking performance of a grouting joint entity throughout its life cycle according to any one of claims 1 to 5, characterized in that: The method for testing the blocking performance of a grouting joint entity throughout its life cycle comprises the following steps: S1. Sample preparation: Prepare paste grouting materials according to design requirements; S2. Sample loading: Loading the sample in the integrated test chamber for curing and testing; S3. Simulating actual maintenance conditions: adjusting the temperature control component according to the temperature environment of the actual site to simulate the temperature conditions of the site; injecting a certain concentration of salt solution into the supply bottles of the two sets of the solution circulation components according to the water chemical environment of the actual site to simulate the groundwater conditions of the site; setting the flow rates of the inlet peristaltic pump and the outlet peristaltic pump in the two sets of the solution circulation components according to the groundwater flow rate of the actual site to simulate the groundwater flow rate of the site; finally, preparing the saturated solution in the gas phase suction control component according to the unsaturated state of the actual site to simulate the unsaturated maintenance conditions; S4. Sample curing: Under the curing conditions set in step S3, curing for a certain number of days to complete the sample curing; S5. Cleaning the solid: After the curing is completed, close the two sets of the solution circulation components and the gas phase suction control component, replace the solution in the supply bottle of the two sets of the solution circulation components with distilled water, adjust the flow rate of the inlet peristaltic pump and the outlet peristaltic pump, and continuously measure the conductivity of the liquid in the collection bottle. When the conductivity is less than half of the conductivity of the salt solution used in the supply bottle of the solution circulation component in step S3, the cleaning of the solid is considered to be completed; S6. Conduct a penetration test using the penetration component; S7. Conduct membrane effect test under saturated / unsaturated state; S8. Take out the knot and divide it into three parts. Use the filter paper method to test the suction of each part of the knot. Take the average value and record it as the actual suction s s ; S9. Change the test conditions, repeat the above test steps, and carry out the grouting joint entity blocking performance test under different working conditions; S10. Draw the relationship curve between curing time, actual suction, permeability coefficient and membrane efficiency coefficient to comprehensively evaluate and predict the blocking performance of the grouting joint.

7. The method for testing the blocking performance of a grouting joint throughout its life cycle according to claim 6, characterized in that: In step S2, loading the sample into the integrated maintenance and testing test chamber specifically includes: The upper sealing body is installed into the rigid cylinder, and the rigid cylinder and the upper sealing body are inverted together, and an inverted "T"-shaped top cover with a specific height is inserted from the bottom of the rigid cylinder to keep the upper sealing body stationary in the rigid cylinder; filter paper of corresponding size is placed on the surface of the permeable stone on the upper sealing body, and then the paste grouting material prepared in advance is filled into the rigid cylinder in layers, and tools are used to continuously tamp it to expel bubbles; then, the upper surface of the paste grouting material is scraped flat with a scraper, and the filter paper is placed on it, and then the base is turned upside down on the rigid cylinder and fastened through the connecting assembly, and finally the entire integrated test chamber for maintenance and testing is quickly turned back to the normal state.

8. The method for testing the blocking performance of a grouting structure throughout its life cycle according to claim 6, characterized in that: In step S6, using the penetration component to carry out a penetration test specifically includes: The valve on the water inlet pipe of the permeation component is opened, and the liquid in the liquid storage container flows into the water inlet on the base through the water inlet pipe. The temperature control component is set to keep the internal temperature of the accommodating cavity consistent with that in step S3. The water output at different times is recorded by the liquid collecting container, and the permeability coefficient is calculated by the following formula: Among them, ΔQ is the flow difference of the seepage fluid at the top and bottom of the structure within Δt time, A is the cross-sectional area of ​​the structure perpendicular to the water flow direction, and I is the hydraulic slope.

9. The method for testing the blocking performance of a grouting structure throughout its life cycle according to claim 6, characterized in that: In step S7, the membrane effect test under saturation state specifically includes: The distilled water in the supply bottle of the solution circulation assembly connected to the permeable stone on the upper sealing body is replaced with a 10 mM manganese sulfate solution, the pressure difference monitoring assembly is turned on, the inlet peristaltic pump and the outlet peristaltic pump in the two sets of the solution circulation assembly are started and the flow rate is adjusted to 25.2 μL / min, and the solution is circulated at the top and bottom ends of the structure body. During the test, the exudate at the top and bottom ends is collected, and the conductivity and concentration changes of the exudate are measured. After the pressure difference value monitored by the pressure difference monitoring assembly is stable, it is considered that the test has reached a stable stage under the action of the 10 mM manganese sulfate solution; After that, the manganese sulfate solution with higher concentration is replaced in turn until the pressure difference value under the last concentration condition is stable, and the grouting solid membrane efficiency test under saturated state is ended. The membrane effect coefficient is calculated using the following formula: Where Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by Δπ=vRTΔC, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the structure, v is the total number of ions contained in the chemical formula of the electrolyte, and R is the universal gas constant (8.314 J·mol -1 ·K -1 ), T is the absolute temperature, and ΔC is the chemical concentration difference between the top and bottom of the structure.

10. The method for testing the blocking performance of a grouting structure throughout its life cycle according to claim 6, characterized in that: In step S7, the membrane effect test under the unsaturated state specifically includes: The distilled water in the supply bottle of the solution circulation assembly connected to the permeable stone on the upper sealing body is replaced with a 10 mM manganese sulfate solution, the pressure difference monitoring assembly and the gas phase suction control assembly are turned on, the suction is controlled to be 4.2 MPa, the inlet peristaltic pump and the outlet peristaltic pump in the two sets of the solution circulation assemblies are started and the flow rate is adjusted to 25.2 μL / min, the solution is circulated at the top and bottom ends of the structure, and the exudate at the top and bottom ends is collected during the test, and the conductivity and concentration changes of the exudate are measured. After the pressure difference value monitored by the pressure difference monitoring assembly is stable, it is considered that the test has reached a stable stage under the action of the 10 mM manganese sulfate solution; After that, the manganese sulfate solution with higher concentration was replaced successively until the pressure difference value under the last concentration condition was stable, and the test of the solid membrane efficiency of the grouting structure under the unsaturated state was ended. The membrane effect coefficient was calculated using the following formula: Wherein, Δπ is the theoretical chemical osmotic pressure difference, which can be calculated by the Van't Hoff formula, ΔP is the actual chemical osmotic pressure difference between the top and bottom of the structure, and s is the loading suction of the gas phase suction control component.

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