An indoor test evaluation system and method for simulating the effect of grouting in broken strata

Abstract

The application is a kind of indoor test evaluation system and method for simulating the effect of grouting in broken stratum, which comprises a simulation matrix module, a customizable fracture generation module, a grouting module, a core sampling module and a multi-dimensional analysis module; the simulation matrix module containing fractures with preset geometric and morphological parameters is prepared by using the customizable fracture generation module; the grouting material to be evaluated is injected into the fractures through the grouting module; after the grouting material is solidified, systematic core sampling is carried out in the characteristic area containing the fractures according to the pre-designed spatial position and direction strategy; the core sample is tested and analyzed in multiple dimensions and multiple scales by using the multi-dimensional analysis module, and the filling efficiency, interface bonding quality and reinforcement effect of the grouting material on the fractures are comprehensively evaluated. The application can accurately control the geometric parameters and mechanical environment of the fractures, and realize quantitative and visual comparative evaluation of different grouting materials, different proportions and different grouting process effects.

Description

Technical Field

[0001] This invention relates to the technical fields of geotechnical engineering and water conservancy and hydropower engineering, and in particular to an indoor test evaluation system and method for simulating the grouting effect in fractured strata. Background Technology

[0002] In engineering projects such as dams, reservoirs, and tunnels, fractured zones in the foundation rock strata are critical areas leading to potential engineering hazards such as seepage and slippage. In major projects like dam foundation reinforcement, tunnel waterproofing, and slope stabilization, grouting treatment of fractured zones and fractured rock masses is a key technology for improving their integrity, impermeability, and mechanical properties. Currently, the evaluation of grouting effectiveness in engineering practice heavily relies on in-situ borehole pressure water tests and limited core sampling observations. These traditional methods have the following drawbacks:

[0003] Field tests are constrained by site and weather conditions, and drilling, grouting, and testing costs are high;

[0004] The geological conditions at the site were complex and unique, making it impossible to conduct comparative tests using different materials and processes on the same crack conditions.

[0005] The width, direction, roughness, water pressure, and other parameters of the cracks on site cannot be precisely controlled and quantified, which will affect the scientific validity and comparability of the test results.

[0006] It is difficult to observe the flow, filling, setting process of grout in complex cracks and the final interface state intuitively and comprehensively.

[0007] Therefore, developing an integrated system and method that can accurately simulate the characteristics of fractured strata in a laboratory environment, realize the visual monitoring of the grouting process, and conduct multi-dimensional, quantitative, and repeatable evaluation of the grouting effect has become an urgent need for the development of geotechnical engineering grouting technology. Summary of the Invention

[0008] The present invention aims to address the shortcomings of the prior art by providing an indoor test evaluation system and method for simulating the grouting effect in fractured strata.

[0009] To achieve the above objectives, the present invention adopts the following technical solution:

[0010] An indoor test evaluation system for simulating the grouting effect in fractured formations includes a matrix simulation module, a customizable fracture generation module, a grouting module, a core sampling module, and a multi-dimensional analysis module.

[0011] The simulated matrix module is used to provide the solid structure that bears the cracks;

[0012] A customizable crack generation module is used to generate cracks with preset parameters inside the simulated matrix module;

[0013] Grouting module, used to inject grout into the crack;

[0014] The core sampling module is used to drill core samples from the simulated matrix module after grouting and solidification according to a plan.

[0015] The multi-dimensional analysis module is used to characterize the drilled core samples through various means, including macroscopic observation, microscopic analysis, and mechanical testing.

[0016] It also includes a process monitoring module and an environmental simulation module;

[0017] The process monitoring module includes at least one of a pressure sensor, a temperature sensor, or a fiber optic sensor installed in the fissure, for real-time acquisition of grouting process data;

[0018] The environmental simulation module is used to apply confining pressure to the simulation matrix module and / or simulate pressurized water flow within the fracture.

[0019] The simulated matrix module is a cast-in-place concrete matrix specimen.

[0020] The customizable crack generation module is a removable partition that is pre-placed in the template before concrete pouring. The crack is the cavity formed after the removable partition is removed. The thickness of the removable partition is between 0.1mm and 20mm, and the surface is constructed with a specific shape to form cracks with corresponding surface and planar shapes.

[0021] The grouting module includes a grouting port communicating with the fissure and grouting equipment for delivering grout to the grouting port.

[0022] An evaluation method, utilizing the aforementioned indoor test evaluation system for simulating the grouting effect in fractured formations, includes the following steps:

[0023] S1. In the laboratory, based on the target geological characteristics, a simulated matrix module containing preset geometric and morphological parameters of fractures is prepared using a customizable fracture generation module.

[0024] S2. Inject the grouting material to be evaluated into the fracture through the grouting module, and select whether to apply boundary conditions simulating formation stress and / or seepage field as needed.

[0025] S3. After the grouting material has cured, systematic core sampling is carried out in the characteristic area containing the cracks according to the pre-designed spatial position and direction strategy to obtain a series of core samples containing the grouting body and the complete matrix on both sides.

[0026] S4. Use the multi-dimensional analysis module to conduct multi-dimensional and multi-scale testing and analysis on the core sample. Based on the multi-dimensional and multi-scale analysis results, comprehensively evaluate the filling efficiency, interfacial bonding quality and reinforcement effect of the grouting material on the crack.

[0027] In step S1, the geometric and morphological parameters of the crack include width, orientation, roughness, two-dimensional or three-dimensional spatial distribution and connectivity.

[0028] In step S2, during the grouting process, at least one parameter among grout pressure propagation, filling front advancement, and temperature change is monitored in real time by a pressure sensor pre-embedded in the crack.

[0029] In step S3, the directional strategy for core sampling includes vertical, parallel, and oblique at a specific angle to the local extension surface of the fracture. The sampling locations cover the vicinity of the grouting port, key nodes of the fracture, the middle region, and the far region.

[0030] Step S4, the multi-dimensional and multi-scale analysis includes:

[0031] Macroscopic defect analysis: Based on visual or 3D scanning, the macroscopic filling defect analysis of the core sample is conducted to observe and analyze the compactness of the slurry filling in the core sample and whether there are voids, honeycombs, or segregated water zones.

[0032] Microscopic interface analysis: Based on high-definition imaging, microscopic observation or scanning electron microscopy, the microstructure analysis of the slurry-matrix interface is carried out to analyze the bonding status of the slurry-matrix interface, whether it is tightly bonded, and whether there are gaps and transition zones in the microstructure.

[0033] Mechanical property testing: Compressive strength, shear strength or tensile strength tests are performed on the core samples to quantitatively evaluate the reinforcement effect;

[0034] Permeability test: A permeability test is performed on the core sample to evaluate the impermeability after grouting;

[0035] Three-dimensional quantitative analysis: CT scans were performed on the core samples, and the space filling rate, porosity, and interfacial contact area of ​​the slurry in the fractures were quantitatively calculated through three-dimensional reconstruction and image analysis.

[0036] The results of macroscopic defect analysis, microscopic interface analysis, mechanical performance testing, permeability testing, and three-dimensional quantitative analysis are fused together, and a comprehensive quantitative score for grouting effect is obtained through weighted calculation or the establishment of a multi-index evaluation system.

[0037] The beneficial effects of this invention are: it can accurately control the geometric parameters and mechanical environment of the "crack", and realize quantitative and visual comparative evaluation of the effects of different grouting materials, different ratios and different grouting processes, providing direct and efficient experimental basis for engineering material selection and process optimization. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the indoor test evaluation system of the present invention;

[0039] Figure 2This is a schematic diagram of one form of the simulated substrate module in this invention;

[0040] Figure 3 This is a schematic diagram of another form of the simulated substrate module in this invention;

[0041] In the diagram: 1-Concrete substrate specimen; 2-Removable partition; 3-Grouting port;

[0042] The following will describe in detail, with reference to the accompanying drawings, embodiments of the present invention. Detailed Implementation

[0043] The principles and features of the present invention are described below with reference to the accompanying drawings. The embodiments given are for illustrative purposes only and are not intended to limit the scope of the invention. The invention is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the invention.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0046] An indoor test evaluation system for simulating the grouting effect in fractured formations, such as... Figure 1 As shown, it includes a simulated matrix module, a customizable fracture generation module, a grouting module, a core sampling module, a multi-dimensional analysis module, a process monitoring module, and an environmental simulation module.

[0047] The simulated matrix module is used to provide a solid entity to bear the cracks. It consists of large-sized (typically no less than 1m×1m×1m) concrete or rock-like material specimens cast in the laboratory. The mix proportions of the specimens are designed so that their mechanical parameters (such as elastic modulus and uniaxial compressive strength) are similar to those of the target engineering rock mass, serving as a matrix to bear artificial cracks and simulate in-situ stress states.

[0048] Preferably, the simulated matrix module is a cast concrete matrix specimen 1.

[0049] The customizable crack generation module, used to generate cracks with preset parameters inside the simulated matrix module, is the core of this invention to achieve high controllability and repeatability.

[0050] The customizable crack generation module is a removable partition 2 pre-placed in the template before concrete pouring. The crack is the cavity formed after the removable partition 2 is removed. The thickness of the removable partition 2 is between 0.1mm and 20mm, and the surface is constructed to have a specific shape to form cracks with corresponding surface and planar shapes.

[0051] like Figure 2 As shown, the removable partition 2 inside the concrete matrix specimen 1 is a straight plate structure, which can be pre-formed with multiple cracks.

[0052] like Figure 3 As shown, the removable partition 2 inside the concrete matrix specimen 1 has a straight plate shape and a broken line shape, and the thickness is also inconsistent, which can be preset to form multiple cracks.

[0053] The specific operation is as follows: Before pouring, metal or polymer partitions of a specific thickness (such as 0.1mm to 20mm), specific surface morphology (smooth, serrated, corrugated, rough sandblasted) and specific planar morphology (straight line, broken line, curve, cross network) are fixed in a predetermined position in the template. After the matrix has initially set, they are pulled out to form a through or semi-through single seam, cross seam or mesh seam.

[0054] Of course, in addition to the prefabricated diaphragm method mentioned above, other methods can also be used to generate cracks.

[0055] For example, pre-embedded inflatable capsules, soluble salt crystals, or strips of low-strength brittle materials can be used to form crack spaces with controllable shape and size at specific stages (such as after curing) through inflation, dissolution and hydration, or mechanical removal.

[0056] For example, based on a three-dimensional digital model, 3D printing technology can be used to directly form a matrix mold containing a complex crack network, or CNC cutting technology can be used to precisely cut inside a large specimen that has already been formed.

[0057] The grouting module is used to inject grout into the fissure. The grouting module includes a grouting port 3 communicating with the fissure and grouting equipment for conveying grout to the grouting port 3.

[0058] Before pouring, the grouting pipe is pre-embedded in the template. After pouring, it is pulled out to form grouting port 3.

[0059] Grouting equipment includes a multi-channel grouting valve group, a high-precision grouting pump (with constant pressure / constant flow control), and a grout mixing and insulation container.

[0060] The core sampling module is used to drill core samples from the simulated matrix module after grouting and solidification according to a plan.

[0061] Using a core drilling rig, systematic drilling is performed according to pre-designed three-dimensional coordinates and directions (perpendicular, parallel, or oblique to the fracture surface) in areas including the grouting port, the middle of the fracture, the distal end, intersections, and suspected defect areas. The core sample diameter (usually 100-200 mm) should be much larger than the fracture width to ensure that representative samples containing intact grout stones and intact matrix on both sides are obtained.

[0062] The multi-dimensional analysis module is used to characterize the drilled core samples through various means, including macroscopic observation, microscopic analysis, and mechanical testing.

[0063] The process monitoring module includes at least one of the following: pressure sensor, temperature sensor, fiber optic (FBG) sensor, resistivity probe, or acoustic emission probe, which is installed in the fissure. It is used to collect grouting process data in real time and monitor the grout pressure propagation, filling front position, temperature change, and micro-fracture activity during the grouting process.

[0064] The environmental simulation module is used to apply confining pressure to the simulated matrix module and / or simulate pressurized water flow within fractures. The entire specimen or a portion thereof is placed in a triaxial pressure chamber, and isotropic / anisotropic confining pressure is applied to simulate grouting under formation stress. Inlets and outlets are pre-set in the fractures and connected to a constant-pressure water supply system to simulate dynamic water grouting under pressurized groundwater conditions.

[0065] An evaluation method, utilizing the aforementioned indoor test evaluation system for simulating the grouting effect in fractured formations, includes the following steps:

[0066] S1. In the laboratory, based on the target geological characteristics, determine the fracture characteristics (width, orientation, roughness, network complexity) and environmental conditions (stress, water pressure) to be simulated. Use a customizable fracture generation module to prepare a simulated matrix module containing preset geometric and morphological parameters of fractures, and pre-embed sensors as needed. Cure the simulated matrix module in a simulated or standard environment to the specified age.

[0067] The geometric and morphological parameters of a crack include its width, orientation, roughness, two-dimensional or three-dimensional spatial distribution, and connectivity.

[0068] At the same time, comparative test groups (such as different materials, water-cement ratio, grouting pressure) can be designed.

[0069] S2. Inject the grouting material to be evaluated into the fracture through the grouting module, and select whether to apply boundary conditions of simulated formation stress and / or seepage field as needed; during the grouting process, monitor at least one parameter of grout pressure propagation, filling front advancement, and temperature change in real time through pressure sensors pre-embedded in the fracture.

[0070] S3. After the grouting material has cured, systematic core sampling is carried out in the characteristic area containing the crack according to the pre-designed spatial location and direction strategy to obtain a series of core samples containing the grouting body and the complete matrix on both sides. The direction strategy of core sampling includes vertical, parallel and oblique to the local extension surface of the crack at a specific angle. The sampling location covers the vicinity of the grouting port, the key nodes of the crack, the middle area and the far end area.

[0071] S4. Use the multi-dimensional analysis module to conduct multi-dimensional and multi-scale testing and analysis on the core sample. Based on the multi-dimensional and multi-scale analysis results, comprehensively evaluate the filling efficiency, interfacial bonding quality and reinforcement effect of the grouting material on the crack.

[0072] Multidimensional and multiscale analysis includes:

[0073] Macroscopic defect analysis: Based on visual or 3D scanning, the macroscopic filling defect analysis of the core sample is conducted to observe and analyze the compactness of the slurry filling in the core sample and whether there are voids, honeycombs, or segregation water bands. Specifically, the core sample is subjected to high-definition 3D scanning and photography to visually assess the continuity and compactness of the slurry filling and identify macroscopic defects such as voids, water seepage channels, and stratification.

[0074] Microscopic interface analysis: Based on high-definition imaging, microscopic observation or scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), the microstructure of the slurry-matrix interface is analyzed to determine the bonding status of the slurry-matrix interface, whether it is tightly bonded, and whether there are gaps and transition zone microstructures; the micromorphology of the interface transition zone, the types of hydration products, the degree of crystallization and element diffusion are observed to evaluate the quality of chemical bonding and physical interlocking.

[0075] Mechanical property testing: The core samples are tested for compressive strength, shear strength (through direct shear test) or tensile strength (through Brazilian splitting test) to quantitatively evaluate the reinforcement effect;

[0076] Permeability test: A permeability test is performed on the core sample to evaluate the impermeability after grouting;

[0077] Three-dimensional quantitative analysis: CT scans were performed on the core samples, and the space filling rate, porosity, and interfacial contact area of ​​the slurry in the fractures were quantitatively calculated through three-dimensional reconstruction and image analysis.

[0078] The results of macroscopic defect analysis, microscopic interface analysis, mechanical performance testing, permeability testing, and three-dimensional quantitative analysis are fused together, and a comprehensive quantitative score for grouting effect is obtained through weighted calculation or the establishment of a multi-index evaluation system. Specific Implementation Example 1:

[0080] Evaluation of the grouting effect of straight fissures:

[0081] 1. Specimen Preparation: Cast a C25 concrete substrate specimen 1 with dimensions of 100cm×100cm×100cm. Before casting, a smooth stainless steel plate with a thickness of 2mm was placed vertically in the center of the specimen as a removable partition 2. After the concrete initially set, the steel plate was removed, thus forming a vertically continuous, straight artificial crack inside the specimen.

[0082] 2. Grouting test: Prepare ordinary Portland cement grout with a water-cement ratio of 0.8:1. Use a piston grouting pump to inject grout from the grouting port located at the bottom of the crack at a constant pressure of 0.3 MPa until uniform grout flows out from the top overflow port and then stop.

[0083] 3. Curing and Sampling: The grout was cured in the mold for 28 days. Using a 150mm diameter diamond drill bit, core samples were drilled at three locations: 20cm, 50cm, and 80cm from the grouting port, in a direction perpendicular to the fracture surface.

[0084] 4. Evaluation of Results:

[0085] Macroscopic observation: The cracks in all three core samples were completely filled with cement paste, which was dense and showed no obvious voids or bleeding zones. Upon dissection of the core samples, it was found that the paste and concrete interface were tightly bonded, with no visible gaps.

[0086] Mechanical testing: Some core samples were processed into standard cylindrical specimens and subjected to uniaxial compressive strength tests. The average compressive strength of the grout-aggregate was measured to be 15 MPa, indicating that the grouting effectively restored the integrity of the matrix. Specific Implementation Example 2:

[0088] Evaluation of the effect of grouting in tortuous cracks:

[0089] 1. Specimen Preparation: Cast a C30 concrete substrate specimen 1 with dimensions of 100cm×100cm×200cm. A 1mm thick, regularly wavy metal plate (3cm amplitude, 8cm wavelength) was pre-placed as a removable partition 2, forming a vertical, tortuous artificial crack. The surface of the metal plate was sandblasted to simulate a rough crack surface.

[0090] 2. Grouting test: An ultrafine cement grouting material (water-cement ratio 0.6:1) was used, and grout was injected from one end of the crack at a constant pressure of 0.5 MPa. A miniature pressure sensor was pre-embedded in the middle of the crack to monitor the propagation of the grouting pressure.

[0091] 3. Curing and Sampling: After 28 days of curing, not only vertical core samples are taken near the grouting port, at the inflection point of the crack, and at the farthest point, but also an additional oblique core sample is taken at the inflection point to more completely capture the filling morphology of the grout in the complex path.

[0092] 4. Evaluation of Results:

[0093] Macroscopic and CT analysis: Vertical core samples showed that the filling was basically complete. CT scans and three-dimensional reconstructions of oblique core samples and some core samples showed that the slurry thickness increased slightly on the inner side of the bends and decreased slightly on the outer side, but the overall connectivity was good, and the overall filling rate was calculated to be 92%.

[0094] Interface microscopic analysis: Scanning electron microscopy revealed that the hydration products of the slurry formed a good mechanical bond with the rough concrete surface treated by sandblasting.

[0095] Permeability test: A permeability test was conducted on a core sample containing grout, and its permeability coefficient was reduced by two orders of magnitude compared to the control sample without grout.

[0096] This invention achieves "geological modeling" and "process parameterization": transforming complex and hidden underground grouting projects into physical models and data streams that can be precisely controlled, intuitively observed, and repeatedly tested in the laboratory, greatly improving the scientific rigor and comparability of the research.

[0097] This invention shifts the evaluation dimensions from "point-based and partial" to "systematic and comprehensive": through a systematic core drilling strategy of "multi-location + multi-directional", combined with a series of analytical methods ranging from millimeters to micrometers, from mechanics to hydraulics, and from morphology to composition, it has constructed the most comprehensive indoor evaluation system for grouting effects to date, revealing the multi-scale nature of grouting effects.

[0098] This invention deeply integrates "simulation, monitoring and evaluation": the system integrates three major functions: environmental simulation, process monitoring and final evaluation. It not only focuses on the final result, but also inverts and analyzes the slurry flow and consolidation process, providing a powerful tool for mechanism research.

[0099] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made using the inventive concept and technical solution of the present invention, or direct application to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. An evaluation method for an indoor test evaluation system simulating the grouting effect in fractured formations, characterized in that, The indoor test evaluation system includes a simulated matrix module, a customizable fracture generation module, a grouting module, a core sampling module, and a multi-dimensional analysis module. The simulated matrix module provides the entity that bears the fractures. The customizable fracture generation module generates fractures with preset parameters inside the simulated matrix module. The grouting module injects grout into the fractures. The core sampling module drills core samples from the grouted and solidified simulated matrix module according to a plan. The multi-dimensional analysis module is used to perform various performance characterizations on drilled core samples, including macroscopic observation, microscopic analysis, and mechanical testing. The evaluation method includes the following steps: S1. In the laboratory, based on the target geological characteristics, a simulated matrix module containing preset geometric and morphological parameters of fractures is prepared using a customizable fracture generation module. S2. The grouting material to be evaluated is injected into the fracture through the grouting module, and the boundary conditions of simulated formation stress and / or seepage field are selected as needed. During the grouting process, at least one parameter of grout pressure propagation, filling front advancement and temperature change is monitored in real time by the pressure sensor pre-embedded in the fracture. S3. After the grouting material has cured, systematic core sampling is carried out in the characteristic area containing the cracks according to the pre-designed spatial position and direction strategy to obtain a series of core samples containing the grouting body and the complete matrix on both sides. S4. Use the multi-dimensional analysis module to conduct multi-dimensional and multi-scale testing and analysis on the core sample. Based on the multi-dimensional and multi-scale analysis results, comprehensively evaluate the filling efficiency, interfacial bonding quality and reinforcement effect of the grouting material on the crack.

2. The evaluation method for an indoor test evaluation system simulating the grouting effect in fractured formations according to claim 1, characterized in that, The indoor test evaluation system also includes a process monitoring module and an environmental simulation module; The process monitoring module includes at least one of a pressure sensor, a temperature sensor, or a fiber optic sensor installed in the fissure, for real-time acquisition of grouting process data; The environmental simulation module is used to apply confining pressure to the simulation matrix module and / or simulate pressurized water flow within the fracture.

3. The evaluation method for an indoor test evaluation system simulating the grouting effect in fractured formations according to claim 1, characterized in that, The simulated matrix module is a cast concrete matrix specimen (1).

4. The evaluation method for an indoor test evaluation system simulating the grouting effect in fractured formations according to claim 1, characterized in that, The customizable crack generation module is a removable partition (2) pre-placed in the template before concrete pouring. The crack is the cavity formed after the removable partition (2) is removed. The thickness of the removable partition (2) is between 0.1 mm and 20 mm, and the surface is constructed to have a specific shape to form a crack with a corresponding surface shape and planar shape.

5. The evaluation method for an indoor test evaluation system simulating the grouting effect in fractured formations according to claim 1, characterized in that, The grouting module includes a grouting port (3) communicating with the fissure and grouting equipment for conveying grout to the grouting port (3).

6. The evaluation method for an indoor test evaluation system for simulating the grouting effect in fractured formations according to any one of claims 1-5, characterized in that, In step S1, the geometric and morphological parameters of the crack include width, orientation, roughness, two-dimensional or three-dimensional spatial distribution and connectivity.

7. The evaluation method for an indoor test evaluation system for simulating grouting effects in fractured formations according to any one of claims 1-5, characterized in that, In step S3, the directional strategy for core sampling includes vertical, parallel, and oblique at a specific angle to the local extension surface of the fracture. The sampling locations cover the vicinity of the grouting port, key nodes of the fracture, the middle region, and the far region.

8. The evaluation method for an indoor test evaluation system for simulating the grouting effect in fractured formations according to any one of claims 1-5, characterized in that, Step S4, the multi-dimensional and multi-scale analysis includes: Macroscopic defect analysis: Based on visual or 3D scanning, the macroscopic filling defect analysis of the core sample is conducted to observe and analyze the compactness of the slurry filling in the core sample and whether there are voids, honeycombs, or segregated water zones. Microscopic interface analysis: Based on high-definition imaging, microscopic observation or scanning electron microscopy, the microstructure analysis of the slurry-matrix interface is carried out to analyze the bonding status of the slurry-matrix interface, whether it is tightly bonded, and whether there are gaps and transition zones in the microstructure. Mechanical property testing: Compressive strength, shear strength or tensile strength tests are performed on the core samples to quantitatively evaluate the reinforcement effect; Permeability test: A permeability test is performed on the core sample to evaluate the impermeability after grouting; Three-dimensional quantitative analysis: CT scans were performed on the core samples, and the space filling rate, porosity, and interfacial contact area of ​​the slurry in the fractures were quantitatively calculated through three-dimensional reconstruction and image analysis. The results of macroscopic defect analysis, microscopic interface analysis, mechanical performance testing, permeability testing, and three-dimensional quantitative analysis are fused together, and a comprehensive quantitative score for grouting effect is obtained through weighted calculation or the establishment of a multi-index evaluation system.

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