Grouting effect evaluation and water pressure test method and system

Abstract

This application provides a water pressure test method and system for evaluating grouting effectiveness, relating to the field of mine water hazard prevention technology, to solve the problem of difficulty in effectively identifying weak areas in grouting. The water pressure test method for evaluating grouting effectiveness includes dividing the grouting hole into multiple isolated independent test sections; conducting a water pressure loading test on each independent test section; conducting a pressure recovery test on each independent test section; calculating segmented hydraulic parameters; obtaining grouting sealing evaluation indicators based on the segmented hydraulic parameters; and identifying weak grouting sealing areas based on the grouting sealing evaluation indicators. This method can more accurately identify weak grouting areas.

Description

Technical Field

[0001] This application relates to the field of mine water hazard prevention technology, and more specifically, to a water pressure test method and system for evaluating grouting effect. Background Technology

[0002] Pre-mining grouting is a key technical measure for preventing water hazards from aquifers in the roof of coal mines, controlling the development height of water-conducting fracture zones, and reducing the permeability of surrounding rock. Its engineering effect directly affects the safe production of the mine and the rational determination of mining intensity. To verify whether the grouting project has achieved the expected sealing effect, a water pressure test is usually carried out on the grouting hole after grouting is completed. The grouting effect is evaluated by measuring the water absorption per unit time or the seepage flow rate per unit pressure.

[0003] Existing water pressure testing methods generally have the following shortcomings: 1. The problem of overall equivalent evaluation is prominent: Traditional water pressure test treats the entire grouting hole as a unified hydraulic unit, and the results obtained are equivalent permeability parameters within the entire hole range, which cannot reflect the differences in grouting and sealing in different depth sections, and the evaluation results have obvious homogenization characteristics.

[0004] 2. Difficulty in identifying locally weak water-conducting sections: Pre-mining grouting is affected by differences in strata lithology, the distribution of primary and mining-induced fractures, structural conditions, and the heterogeneity of grout diffusion. The sealing effect often exhibits obvious segmentation in the vertical direction. Overall pressure testing can easily mask locally high-conductivity sections, making it impossible to accurately identify potential water hazard risks.

[0005] 3. Effective guidance for targeted grouting construction: Due to the lack of understanding of the spatial distribution characteristics of grouting effects, existing evaluation methods are unable to provide clear section positioning and parameter optimization basis for subsequent grouting construction, which can easily lead to an expansion of the grouting range, waste of grouting materials, or omission of key water guiding channels. Summary of the Invention

[0006] The first aspect of this application aims to provide a water pressure test method for evaluating grouting effect, so as to solve the technical problem that weak areas in existing grouting systems are difficult to identify effectively.

[0007] The grouting effect evaluation water pressure test method provided in the first aspect of this application includes: The grouting holes were divided into multiple isolated, independent test sections; A pressure water loading test was conducted on each of the aforementioned independent test sections. A pressure recovery test was performed on each of the independent test sections. Perform segmented hydraulic parameter calculations; The grouting and sealing evaluation index is obtained based on the segmented hydraulic parameters; The grouting and sealing evaluation index is used to identify sections with weak grouting and sealing effects.

[0008] The beneficial effects of the grouting effect evaluation water pressure test method in this application are: By dividing the grouting hole into multiple isolated independent test sections, pressure loading and pressure recovery tests can be performed on each independent test section to obtain the results for each section separately. This allows for a more refined evaluation of the sealing effect, accurate identification of weak grouting sections, and effective identification of local high-conductivity areas and potential residual water channels, reducing the risk of water damage. Furthermore, this method is compatible with existing grouting holes and pressure testing equipment, making it suitable for downhole field use.

[0009] In the optional technical solution, the length of each independent test section is 5m to 20m; and / or, in the process of dividing the grouting hole into multiple isolated independent test sections, a double packer or a multi-stage packer is inserted into the grouting hole and sealed with the hole wall by means of air inflation or pressurization.

[0010] In the optional technical solution, the independent test section is consistent with the grouting construction section.

[0011] In the optional technical solutions, the pressure loading test includes at least one of constant pressure loading test, constant flow loading test, stepped loading test, and pulse loading test; the constant pressure loading test is the process of injecting water into the independent test section at a preset pressure level and recording the change of water volume over time; the constant flow loading test is the process of injecting water into the independent test section under a fixed flow rate and recording the pressure response; the stepped loading test is the process of obtaining the response characteristics of the independent test section to transient hydraulic force through a step loading method; the pulse loading test is the process of obtaining the response characteristics of the independent test section to transient hydraulic force through a pulse loading method.

[0012] In the optional technical solutions, the segmented hydraulic parameters include the unit pressure difference water absorption coefficient, the equivalent permeability index, and the pressure recovery time constant.

[0013] In an optional technical solution, the pressure recovery test includes recording the pressure recovery or decay curve over time in the independent test section after water injection is stopped, and extracting the pressure recovery time characteristic parameters.

[0014] In an optional technical solution, the pressure recovery time characteristic parameter is obtained by fitting an exponential function to the pressure recovery or attenuation curve in the independent test section after the pressure water loading test is stopped. The exponential function is used to characterize the equivalent water storage-seepage coupling characteristics of the independent test section.

[0015] In an optional technical solution, the equivalent permeability index is calculated based on the radial seepage model of the independent test section under steady-state pressure water conditions. The radial seepage model is based on the length, pore size, equivalent influence radius, and effective pressure difference of the independent test section.

[0016] In an optional technical solution, obtaining the grouting and sealing evaluation index based on the segmented hydraulic parameters includes: constructing the grouting and sealing evaluation index by comparing the segmented hydraulic parameters before and after grouting, or by comparing the segmented hydraulic parameters of different independent test sections of the same grouting hole; if the grouting and sealing evaluation index of the independent test section is higher than the index threshold, the independent test section is determined to be a weak section for grouting and sealing.

[0017] The second aspect of this application aims to provide a water pressure testing system to solve the technical problem of the difficulty in effectively identifying weak areas in grouting.

[0018] The second aspect of this application provides a pressure water testing system for evaluating the grouting effect of any of the above-mentioned methods. The pressure water testing system includes: a sealing component, a pressurized water injection unit, a monitoring unit, and a data processing unit. The sealing component is configured to be located at the grouting hole and to divide the grouting hole into independent test sections. The pressurized water injection unit is configured to provide controllable water pressure or controllable flow rate to the independent test sections. The monitoring unit is configured to collect pressure data, flow rate data, and time data. The data processing unit is configured to calculate the segmented hydraulic parameters and grouting sealing evaluation indicators.

[0019] By setting up the aforementioned water pressure test system, the grouting hole can be divided into multiple independent test sections. This allows for the measurement of relevant segmental hydraulic parameters for each independent test section and the acquisition of grouting and sealing evaluation indicators. Consequently, the grouting and sealing effect of the grouting hole can be judged more specifically and accurately. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments or background art of this application, the drawings used in the description of the embodiments or background art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating the water pressure test method for evaluating the grouting effect provided in Embodiment 1 of this application.

[0022] Figure 2 This is a flowchart illustrating a specific embodiment of the grouting effect evaluation water pressure test method provided in Embodiment 1 of this application.

[0023] Figure 3 This is a schematic diagram of the water pressure test system provided in Embodiment 2 of this application.

[0024] Explanation of reference numerals in the attached figures: 10-Packing assembly; 11-Upper packer of water-blocking airbag; 12-Lower packer of water-blocking airbag; 13-High-pressure nitrogen cylinder; 14-Gas delivery pipe; 15-Gas outlet; 20-Pressurized water injection unit; 21-Water inlet pipe; 22-Water inlet; 23-Water outlet; 30-Monitoring unit; 40-Data processing unit; 50-Grouting hole; 51-Borehole wall; 52-Water-stopping layer; 53-Weak point; 60-Independent test section; 70-Wellhead protection device. Detailed Implementation

[0025] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0026] Example 1: Figure 1 This is a schematic flowchart of the water pressure test method for evaluating the grouting effect provided in Embodiment 1 of this application. Figure 1 As shown, the grouting effect evaluation water pressure test method provided in Embodiment 1 of this application includes: S210. Divide the grouting hole 50 into multiple isolated independent test sections 60; S220. Perform a pressure water loading test on each independent test section 60. S230. Perform a pressure recovery test on each independent test section 60. S240, Perform segmented hydraulic parameter calculations; S250. The grouting and sealing evaluation index is obtained based on the segmented hydraulic parameters. S260. Identify sections with weak grouting and sealing effects based on grouting and sealing evaluation indicators.

[0027] By dividing the grouting hole 50 into multiple isolated independent test sections 60, pressure loading and pressure recovery tests can be performed on each independent test section 60 to obtain the results for each independent test section 60. This allows for a more refined evaluation of the sealing effect, accurate identification of weak grouting sections, and effective identification of local high-conductivity areas and potential residual water channels, reducing the risk of water damage. Moreover, this method is compatible with existing grouting holes 50 and pressure testing equipment, making it suitable for downhole field use.

[0028] Optionally, the length of each independent test section 60 is 5m to 20m; and / or, the grouting hole 50 is divided into multiple isolated independent test sections 60, and a double packer or multi-stage packer is inserted into the grouting hole 50 to form a seal with the hole wall 51 of the grouting hole 50 by means of air inflation or pressurization.

[0029] Selecting the above-mentioned length for the independent test section 60 can improve the testing precision of the grouting hole 50 while ensuring testing efficiency. Furthermore, using double or multi-stage packers allows for the division of the test section 60 into multiple independent test sections, thereby improving operational efficiency.

[0030] Based on the depth of the grouting hole 50, the grouting construction segment records, and the geological structure characteristics, the grouting hole 50 is divided into multiple independent test sections 60 along the drilling depth direction. The length of each independent test section 60 ranges from 5m to 20m. Specifically, during testing, two adjacent packers can be used to form a seal with the hole wall 51 of the grouting hole 50 within the target depth range, making the section between the two packers hydraulically independent from other sections within the grouting hole 50.

[0031] Optionally, the independent test section 60 is consistent with the grouting construction section.

[0032] This setup improves the targeting of segmented testing during grouting construction, thereby enhancing testing effectiveness. Alternatively, in another implementation, the critical aquifer and / or fracture development zone can be further subdivided to create multiple independent test sections.

[0033] Optionally, the pressure loading test includes at least one of constant pressure loading test, constant flow loading test, stepped loading test, and pulse loading test; the constant pressure loading test is the process of injecting water into the independent test section 60 at a preset pressure level and recording the change of water volume over time; the constant flow loading test is the process of injecting water into the independent test section 60 under a fixed flow rate and recording the pressure response; the stepped loading test is the process of obtaining the response characteristics of the independent test section 60 to transient hydraulic forces through a stepped loading method; the pulse loading test is the process of obtaining the response characteristics of the independent test section 60 to transient hydraulic forces through a pulse loading method.

[0034] By setting up a pressure water loading test including the above test methods, the water absorption capacity of 60 independent test sections under different hydraulic conditions can be tested, thereby improving the reliability of the test.

[0035] Optionally, the segmented hydraulic parameters include the unit pressure differential water absorption coefficient, the equivalent permeability index, and the pressure recovery time constant.

[0036] Specifically, for the i-th test section, during the pressurized water loading process, when the injection flow rate reaches a stable or quasi-stable state, the water absorption Qi of that independent test section 60 during the stable injection flow rate stage is obtained. ，ss And the effective pressure difference ΔP of the corresponding independent test section 60. i The effective pressure difference is the difference between the applied pressure and the initial pressure within the test section. The unit pressure difference water absorption coefficient qi=Q for the i-th independent test section 60. i，ss / △P i When using a stepped loading method, the unit pressure difference water absorption coefficient can be calculated separately under different pressure levels, and the average value can be taken, or the representative unit pressure difference water absorption coefficient of the independent test section 60 can be obtained through regression analysis.

[0037] Optionally, the pressure recovery test includes recording the pressure recovery or decay curve over time within an independent test section 60 after water injection is stopped, and extracting the pressure recovery time characteristic parameters.

[0038] Optionally, the pressure recovery time characteristic parameter is obtained by fitting an exponential function to the pressure recovery or decay curve within the independent test section 60 after the pressure water loading test is stopped. The exponential function is used to characterize the equivalent water storage-seepage coupling characteristics of the independent test section 60.

[0039] After the pressurized water loading stopped, pressure recovery tests were conducted on each independent test section 60, and the pressure change over time within each independent test section 60 was recorded. The pressure recovery time characteristic parameter τ was extracted by analyzing the pressure recovery or pressure decay curves. i It is used to characterize the water storage-seepage coupling characteristics of the independent test section 60.

[0040] The pressure recovery process can be fitted using an exponential function, where the pressure P in the test section at time t after water injection stops is measured. i (t) = P i，∞ +(P) i，0 -P i，∞ )exp(-t / τ i ); where P i，0 The pressure at the moment the water injection stops; P i，∞ τ is the pressure when the pressure returns to a steady state. i Let τ be the pressure recovery time characteristic parameter for the i-th independent test segment 60. The pressure recovery time characteristic parameter τ can be determined by regression fitting of the above relationship, or based on the time corresponding to the pressure recovery to the characteristic proportion. i .

[0041] Optionally, the equivalent permeability index is calculated based on the radial seepage model of the independent test section 60 under steady-state pressure water conditions. The radial seepage model is based on the length, pore size, equivalent influence radius, and effective pressure difference of the independent test section 60.

[0042] Introducing an equivalent permeability index ki can quantitatively characterize the overall seepage capacity of the test section after grouting. Under the assumption that the seepage process within a 60-meter independent test section is approximately steady-state radial seepage, the equivalent permeability index k... i =ln(r e / r w )·μQ i，ss / (2πL i △P i μ is the dynamic viscosity of the injected fluid; L i The length of the independent test segment is 60; r w r is the borehole radius; e The equivalent influence radius of the independent test section 60; △P i This refers to the effective pressure difference within a 60-meter independent test section. Under different engineering conditions, the equivalent permeability index can also be equivalently converted or characterized based on the unit pressure difference water absorption coefficient or equivalent head loss relationship.

[0043] Optionally, the grouting sealing evaluation index is obtained based on the segmented hydraulic parameters, including: constructing the grouting sealing evaluation index by comparing the segmented hydraulic parameters before and after grouting, or by comparing the segmented hydraulic parameters of different independent test sections 60 of the same grouting hole 50; if the grouting sealing evaluation index of the independent test section 60 is higher than the index threshold, the independent test section 60 is determined to be a weak section for grouting sealing.

[0044] When the grouting and sealing evaluation index is low, it indicates that the corresponding independent test section 60 has a weak water absorption capacity per unit pressure difference, low equivalent permeability, and a slow pressure recovery rate, indicating that the grouting and sealing effect within the independent test section 60 is good. When the grouting and sealing evaluation index is high, it indicates that the independent test section 60 still has strong hydraulic connectivity or residual water conduction channels, and can be identified as a weak section for grouting and sealing.

[0045] The segmented hydraulic parameters of the i-th independent test section 60 include the unit pressure difference water absorption coefficient q. i Equivalent permeability index k i and the pressure recovery time characteristic parameter τ i The above parameters are then subjected to dimensionless standardization to obtain the corresponding standardized parameters q. i * k i * and τ i *Based on standardized parameters, a segmented grouting sealing effect evaluation function Ei=f(q) is constructed. i * k i * , τ i * The evaluation function f(q) i * k i * , τ i * E is a monotonic function used to comprehensively characterize the hydraulic connectivity and grouting sealing integrity of the test section. Specifically, E i =f(q) i * k i * , τ i * ), can be, E i =aq i * +bk i * +τ i *， a and b can be coefficients no greater than 1.

[0046] Figure 2 This is a flowchart illustrating a specific embodiment of the water pressure test method for evaluating the grouting effect provided in Embodiment 1 of this application. Figure 2 As shown, the grouting effect evaluation water pressure test method provided in this embodiment specifically includes the following steps: S301. Insert multiple packers into the grouting hole 50 to divide the grouting hole 50 into 6 isolated independent test sections 60, each independent test section 60 being 10m long. S302. Using a double packer, a closed independent test section 60 is formed in the target section. A water pressure loading test is carried out on each independent test section 60, specifically a constant pressure loading test. For example, a constant pressure water pressure test is carried out at three pressure levels: 0.5MPa, 1.0MPa and 1.5MPa, and the change in water absorption is recorded. S303. Perform pressure recovery tests on each independent test section 60 and record the pressure recovery process after stopping water injection. S304. Perform segmented hydraulic parameter calculations, including unit pressure differential water absorption coefficient, equivalent permeability index, and pressure recovery time constant. S305. The grouting and sealing evaluation index is obtained based on the segmented hydraulic parameters; S306. Identify sections with weak grouting and sealing effects based on grouting and sealing evaluation indicators.

[0047] The experimental results show that the water absorption coefficient per unit pressure difference varies significantly among different independent test sections 60. One particular independent test section 60 has a significantly higher water absorption coefficient and is identified as a weak point in the grouting sealing process. After re-grouting and retesting this section, the water absorption coefficient has significantly decreased, verifying the effectiveness of the method of this invention. Example 2: Figure 3 This is a schematic diagram of the water pressure testing system provided in Embodiment 2 of this application. Figure 3 As shown, Embodiment 2 also provides a water pressure testing system for evaluating the grouting effect of any of the above-mentioned methods. The water pressure testing system includes: a sealing component 10, a pressurized water injection unit 20, a monitoring unit 30, and a data processing unit 40. The sealing component 10 is configured to be located at the grouting hole 50 and to divide the grouting hole 50 into independent test sections 60. The pressurized water injection unit 20 is configured to provide controllable water pressure or controllable flow rate to the independent test sections 60. The monitoring unit 30 is configured to collect pressure data, flow rate data, and time data. The data processing unit 40 is configured to calculate the segmented hydraulic parameters and grouting sealing evaluation indicators.

[0048] By setting up the aforementioned water pressure test system, the grouting hole 50 can be divided into multiple independent test sections 60. The relevant segmental hydraulic parameters of each independent test section 60 can be measured and the grouting and sealing evaluation index can be obtained, thereby enabling a more specific and accurate judgment on the grouting and sealing effect of the grouting hole 50.

[0049] The sealing assembly 10 may include a high-pressure nitrogen cylinder 13, which is connected to the upper packer 11 and the lower packer 12 of the water-blocking airbag via a gas guide pipe 14. The gas guide pipe 14 has an outlet 15 inside both the upper and lower packers 11 and 12 to supply gas to them. The space between the upper and lower packers 11 and 12 is an independent test section 60. A water-stopping layer 52 is formed on the hole wall 51 of the grouting hole 50 through grouting. This water-stopping layer 52 may have weak points 53. Figure 3 The illustration shows the weak point 53 located within the independent test section 60. The pressurized water injection unit 20 includes an inlet pipe 21, whose inlet 22 is connected to a pump (not shown), and whose outlet 23 is located within the aforementioned independent test section 60, for supplying and pressurizing water to the section. The monitoring unit 30 includes a level sensor located within the independent test section 60 to measure the water pressure. The level sensor is electrically connected to the data processing unit 40. The data processing unit 40... Figure 3The diagram illustrates the shape of a display electrically connected to the monitoring unit 30. Those skilled in the art will understand that the data processing unit 40 obviously includes not only a display but also a processor, etc. The processor can be an industrial computer, PLC, etc., but the display has a more distinctive visual appearance. This application... Figure 3 The data processing unit 40 is represented in this image. Furthermore, a wellhead protection device 70 is installed at the top of the grouting hole 50. While this application discloses the above information, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of this application; therefore, the scope of protection of this application shall be determined by the scope defined in the claims.

[0050] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the term "comprising" or any other variations thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0051] In the above embodiments, descriptions of directions such as "up" and "down" are based on the accompanying drawings.

[0052] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application.

[0053] Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A water pressure test method for evaluating grouting effect, characterized in that, include: The grouting hole (50) is divided into multiple isolated independent test sections (60). Each of the independent test sections (60) was subjected to a water pressure loading test; A pressure recovery test was performed on each of the independent test sections (60); Perform segmented hydraulic parameter calculations; The grouting and sealing evaluation index is obtained based on the segmented hydraulic parameters; The grouting and sealing evaluation indexes are used to identify sections with weak grouting and sealing effects.

2. The water pressure test method for evaluating grouting effect according to claim 1, characterized in that, Each of the independent test sections (60) is 5m to 20m long; and / or, in the process of dividing the grouting hole (50) into multiple isolated independent test sections (60), a double packer or a multi-stage packer is inserted into the grouting hole (50) and sealed with the hole wall (51) of the grouting hole (50) by means of air filling or pressurization.

3. The water pressure test method for evaluating grouting effect according to claim 2, characterized in that, The independent test section (60) is consistent with the grouting construction section.

4. The water pressure test method for evaluating grouting effect according to claim 1, characterized in that, The pressure loading test includes at least one of constant pressure loading test, constant flow loading test, stepped loading test and pulse loading test; the constant pressure loading test is the process of injecting water into the independent test section (60) at a preset pressure level and recording the change of water volume over time; the constant flow loading test is the process of injecting water into the independent test section (60) under a fixed flow rate and recording the pressure response; the stepped loading test is the process of obtaining the response characteristics of the independent test section (60) to transient hydraulic force through a step loading method; the pulse loading test is the process of obtaining the response characteristics of the independent test section (60) to transient hydraulic force through a pulse loading method.

5. The water pressure test method for evaluating grouting effect according to any one of claims 1-4, characterized in that, The segmented hydraulic parameters include the unit pressure differential water absorption coefficient, the equivalent permeability index, and the pressure recovery time constant.

6. The water pressure test method for evaluating grouting effect according to claim 5, characterized in that, The pressure recovery test includes recording the pressure recovery or decay curve over time within the independent test section (60) after water injection is stopped, and extracting the pressure recovery time characteristic parameters.

7. The water pressure test method for evaluating grouting effect according to claim 6, characterized in that, The pressure recovery time characteristic parameter is obtained by fitting the pressure recovery or decay curve in the independent test section (60) after the pressure water loading test is stopped using an exponential function. The exponential function is used to characterize the equivalent water storage-seepage coupling characteristics of the independent test section (60).

8. The water pressure test method for evaluating grouting effect according to claim 5, characterized in that, The equivalent permeability index is calculated based on the radial seepage model of the independent test section (60) under steady-state pressure water conditions. The radial seepage model is based on the length, pore size, equivalent influence radius and effective pressure difference of the independent test section (60).

9. The water pressure test method for evaluating the grouting effect according to any one of claims 1-4, characterized in that, The grouting and plugging evaluation index obtained based on the segmented hydraulic parameters includes: By comparing the segmented hydraulic parameters before and after grouting, or by comparing the segmented hydraulic parameters of different independent test sections (60) of the same grouting hole (50), a grouting sealing evaluation index is constructed. Based on the grouting and sealing evaluation indicators, the weak grouting and sealing sections identified include: If the grouting and sealing evaluation index of the independent test section (60) is higher than the index threshold, the independent test section (60) is determined to be a weak grouting and sealing section.

10. A water pressure testing system, characterized in that, The water pressure test method for evaluating the grouting effect according to any one of claims 1-9 is used to implement the water pressure test system comprising: a sealing component (10), a pressurized water injection unit (20), a monitoring unit (30), and a data processing unit (40). The sealing component (10) is configured to be located at the grouting hole (50) and to divide the grouting hole (50) into independent test sections (60). The pressurized water injection unit (20) is configured to provide controllable water pressure or controllable flow rate to the independent test sections (60). The monitoring unit (30) is configured to collect pressure data, flow rate data, and time data. The data processing unit (40) is configured to calculate the segmented hydraulic parameters and the grouting sealing evaluation index.

Images