A construction method for verifying effect of tunnel curtain grouting

Abstract

The present application relates to the technical field of tunnel and underground engineering, and particularly relates to a construction method for verifying grouting effect of tunnel curtain, which comprises the following steps: adding fluorescent dye tracer into grouting slurry to prepare fluorescent tracer slurry, the tracer can present identifiable optical characteristics under white light or excitation light and is compatible with the slurry; using the fluorescent tracer slurry to conduct curtain grouting, so that the slurry enters into the pores, fissures and fracture zones of surrounding rock to form filling bodies with tracer marks after condensation; after condensation, the excavation surface is irradiated, and / or a probe hole is drilled and the hole wall image is collected to obtain optical images reflecting the distribution of the tracer marks; according to the continuity, coverage range and blank area position of the distribution of the tracer marks in the images, the grouting effect and weak areas are judged, and the weak areas are supplemented and / or the hole spacing, proportioning or pressure is adjusted. The present application realizes the visualization of the grouting diffusion and filling state, can timely find the weak areas and guide the optimization of grouting parameters, and provides direct and reliable auxiliary basis for the determination of the curtain grouting effect.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, and in particular to a construction method for assisting in the verification of the effect of tunnel curtain grouting. Background Technology

[0002] When tunnels traverse water-rich sand layers, fault fracture zones, fractured zones, or loose and fractured surrounding rock, measures such as advanced curtain grouting, radial grouting, or localized reinforcing grouting are often used to plug water, reinforce the structure, and control settlement. Accurate assessment of the grouting effect directly impacts construction safety and subsequent excavation plans. Currently, judging the effectiveness of curtain grouting mainly relies on a comprehensive evaluation using grouting pressure, grouting volume, PQt curve, final borehole pressure, borehole water output, as well as inspection hole pressure or injection tests, core sampling, and geophysical exploration methods such as ground-penetrating radar or transient electromagnetic methods.

[0003] While the above methods can reflect the grouting effect to some extent, they have significant shortcomings in complex strata such as water-rich sand layers and fault fracture zones.

[0004] 1. The method of judging grouting parameters is too indirect and cannot intuitively reflect whether the grout has actually entered the pores, cracks or weak areas in front of the tunnel face of the sand layer; 2. Inspection holes, core sampling, and water pressure tests only reflect the local situation. In sand layers, muddy interlayers, and strongly fractured zones, the integrity of core samples is poor, making it difficult to accurately identify the slurry diffusion boundary and the continuity of filling. 3. Geophysical exploration methods are greatly affected by site conditions, differences in the electrical properties of the surrounding rock, and water-bearing state. The interpretation results are uncertain and it is difficult to guide the dynamic adjustment of grouting parameters at the working face in a timely manner. 4. After ordinary cement grout or cement-water glass grout sets, its color is similar to that of the natural surrounding rock. When excavating or imaging inside the borehole, it is not easy for on-site personnel to distinguish the grout filling body, natural interlayers and fractured surrounding rock, making it difficult to visually verify the distribution of grout. 5. In multi-hole, multi-sequence curtain grouting, grout from different holes and stages overlaps with each other, and there is a lack of low-cost, visual tracing methods to help determine the source and diffusion effect of the grout.

[0005] Therefore, existing methods for verifying the effectiveness of curtain grouting are significantly lacking in terms of intuitiveness, accuracy, and timeliness of construction guidance. There is an urgent need for an auxiliary verification method that can make the grout slurry have identifiable characteristics in subsequent excavation or borehole testing, so as to intuitively and quickly determine the slurry diffusion, filling range, and location of weak areas. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing methods for verifying the effect of tunnel curtain grouting, which are difficult to intuitively display the diffusion and filling state of grout in the pores, fissures and fracture zones of the surrounding rock, make it difficult to detect local weak areas in a timely manner, and lack the basis for dynamic optimization of grouting parameters based on visualization. This invention provides a construction method for auxiliary verification of the effect of tunnel curtain grouting.

[0007] This invention provides a construction method for auxiliary verification of the effect of tunnel curtain grouting, comprising the following steps: S1: Add the fluorescent staining tracer to the grouting slurry and mix evenly to prepare the fluorescent tracer slurry; the fluorescent staining tracer can exhibit identifiable optical features under white light or excitation light irradiation and is compatible with the grouting slurry; S2: Use the fluorescent tracer slurry to perform curtain grouting on the section to be verified, so that the fluorescent tracer slurry enters the pores, fissures and / or fracture zones of the surrounding rock and solidifies to form a filling body with tracer markers; S3: After the grout has solidified, verify the grouting effect: Illuminate the excavation face of the grouting reinforcement area with white light or excitation light, and / or drill a probe hole at the working face, insert an imaging probe with white light or excitation light supplementary lighting function into the probe hole to collect the hole wall image and obtain an optical image reflecting the distribution of the tracer mark. S4: Based on the continuity of the distribution of tracer marks in the optical image, the coverage area, and the location of blank areas with missing tracer marks, determine the grouting filling effect and weak areas, and supplement the weak areas with grouting, and / or adjust the hole spacing, grout ratio, or grouting pressure of subsequent curtain grouting.

[0008] This invention, by adding a fluorescent dyeing tracer with identifiable optical characteristics under white light or excitation light to the grout, allows the grout to solidify in the pores, fissures, and fractured zones of the surrounding rock, forming a filling body with tracer marks. This visualizes the diffusion and filling status of the grout. By illuminating the excavation face with white light or excitation light, and / or by drilling exploratory holes and using an imaging probe with supplemental lighting to acquire images of the hole walls, optical images reflecting the distribution of tracer marks can be obtained intuitively. Based on the continuity, coverage, and blank areas of the tracer marks, the grouting filling effect and weak areas can be accurately determined, and weak areas can be supplemented with grout, and / or the hole spacing, grout mix ratio, or grouting pressure of subsequent curtain grouting can be adjusted. This solves the technical problems of existing curtain grouting effect verification methods, such as the difficulty in intuitively displaying the grout diffusion and filling status, the difficulty in timely detection of local weak areas, and the lack of visual basis for dynamic optimization of grouting parameters. It provides a direct and reliable auxiliary basis for judging the effect of curtain grouting and optimizing construction parameters.

[0009] Preferably, the fluorescent staining tracer is a water-soluble tracer, and the amount of the fluorescent staining tracer added is 0.001% to 0.5% of the slurry mass.

[0010] By adding a water-soluble fluorescent dyeing tracer to the grout and controlling the addition amount to 0.001% to 0.5% of the grout mass, the uniform dispersion and stable compatibility of the tracer in the grout are ensured. Without significantly affecting the grout fluidity, setting time, and strength of the aggregate, a tracer mark that can be effectively identified by white light or excitation light is obtained, taking into account both the grout construction performance and the identification sensitivity.

[0011] Preferably, the grout is cement grout, cement-water glass grout, or chemical grout.

[0012] This method is applicable to cement grout, cement-water glass grout, or chemical grout commonly used in curtain grouting, making the fluorescent staining tracer technology widely compatible with existing grouting materials and construction processes, and has good field adaptability and versatility.

[0013] Preferably, in S2, for porous or multi-sequence grouting, fluorescent dyeing tracers with different colors and / or different concentrations are added to the grouting slurry corresponding to different pore positions or different sequences, so as to form tracer marks in the filling body that can distinguish the source of slurry and the diffusion superposition relationship.

[0014] For multi-hole or multi-sequence curtain grouting, by using fluorescent dyeing tracers of different colors and / or concentrations at different hole locations or sequences, tracer marks that can distinguish the source and diffusion superposition relationship of grout can be formed in the filling body. This facilitates the tracing of the diffusion range and overlapping area of ​​grout at different hole locations and sequences during subsequent excavation or borehole testing, providing a direct basis for optimizing the layout of grouting holes and the grouting sequence.

[0015] Preferably, in S3, the same location in the grouting reinforcement area is subjected to dual-mode irradiation or imaging acquisition using white light and excitation light respectively, and the white light image and excitation light image are compared and identified.

[0016] After irradiating or imaging the same location in the grouting reinforcement area with both white light and excitation light, the white light image and the excitation light image are obtained and compared for identification. This can effectively eliminate the interference of the natural color of the surrounding rock or ambient light, reduce the probability of misjudgment or omission of the tracer marker, and improve the accuracy and reliability of optical interpretation.

[0017] Preferably, in S3, when drilling exploratory boreholes at the working face, the exploratory borehole locations include at least one of the following: inside and outside the curtain grouting design outline, between grouting holes, and near the water inflow point. The depth and angle of the exploratory boreholes are configured to cover the boundary of the design reinforcement ring and suspected weak areas.

[0018] By drilling exploratory holes at key locations such as inside and outside the design outline of curtain grouting, between grouting holes, and near water inflow points, and configuring the depth and angle of the exploratory holes to cover the boundary of the design reinforcement ring and suspected weak areas, it is ensured that the detection range can effectively capture grouting blind spots and potential hidden dangers, avoid misjudgments caused by only verifying near the grouting holes, and achieve a systematic evaluation of the spatial distribution of grouting effect.

[0019] Preferably, in S4, the indicators used to determine the grouting filling effect and weak areas include at least one of the following: the depth of the tracer mark in the optical image, the continuous length, the hole wall coverage, the crack filling rate, and the location of the blank segment without tracer mark.

[0020] By comprehensively using indicators such as the appearance depth, continuous length, borehole wall coverage, crack filling rate, and the location of blank sections without tracer marks, the grouting filling effect and weak areas can be judged. This enables quantitative or semi-quantitative evaluation of the grouting effect from multiple dimensions such as depth range, continuity, coverage area, and defect location, thereby improving the comprehensiveness and objectivity of the judgment results.

[0021] Preferably, in S4, before filling the weak area, another fluorescent dyeing tracer with a different color or concentration than the fluorescent dyeing tracer that forms the filling body is added to the filling grout, and the entry range of the filling grout is determined by verifying the grouting effect again.

[0022] When replenishing weak areas, a different fluorescent staining tracer with a different color or concentration than the tracer in the original filling body is used. The distribution range of the original grout and the replenished grout can be clearly distinguished by the effect of re-grouting. The effectiveness of the replenished grout in entering the original unfilled area can be visually judged, thereby verifying the effectiveness of the replenishment measures and providing a basis for further adjustment of the replenishment parameters.

[0023] Preferably, in step S1, before adding the fluorescent dyeing tracer to the grout, the method further includes: conducting a compatibility test to determine the effect of the fluorescent dyeing tracer on the grout flowability, setting time, bleeding rate and stone strength, and determining the type and amount of tracer to be added based on the test results.

[0024] Before formally preparing the fluorescent tracer grout, a compatibility test is conducted to determine the effects of the fluorescent dyeing tracer on the grout's fluidity, setting time, bleeding rate, and stone strength. Based on the test results, the type and amount of tracer to be added are determined, which can effectively avoid potential grouting quality problems caused by incompatibility between the tracer and the grout, and ensure the safety and reliability of the grouting construction.

[0025] Preferably, S2 further includes: after the grout is prepared, establishing a corresponding record of the grouting construction ledger and the tracer mark; wherein the record includes the hole number, sequence, grouting time, grouting pressure, cumulative grouting volume, fluorescent dye tracer name or number, tracer color and tracer concentration.

[0026] By establishing a corresponding record between the grouting construction ledger and the tracer markers, information such as hole number, sequence, grouting time, grouting pressure, cumulative grouting volume, and tracer name or number, color, and concentration are formed into a complete closed-loop data. This facilitates the accurate matching of the tracer marker information in the optical image with the specific grouting construction parameters during subsequent quality acceptance, technical summary, or problem tracing, thereby improving the traceability of the data and the scalability of the construction method.

[0027] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a construction method for auxiliary verification of the effect of tunnel curtain grouting. By adding a fluorescent dyeing tracer with identifiable optical characteristics under white light or excitation light to the grout, the grout solidifies in the pores, fissures, and fractured zones of the surrounding rock to form a filling body with tracer marks, thus visualizing the diffusion and filling status of the grout. By illuminating the excavation face with white light or excitation light, and / or by drilling exploratory holes and combining them with an imaging probe with supplementary lighting to acquire images of the hole walls, optical images reflecting the distribution of tracer marks can be obtained intuitively. Based on the continuity, coverage, and blank area location of the tracer marks, the grouting filling effect and weak areas can be accurately judged, and weak areas can be supplemented with grout, and / or the hole spacing, grout mix ratio, or grouting pressure of subsequent curtain grouting can be adjusted. This solves the technical problems of existing curtain grouting effect verification methods, which are difficult to intuitively display the grout diffusion and filling status, are not easy to detect local weak areas in a timely manner, and lack visual basis for dynamic optimization of grouting parameters. It provides a direct and reliable auxiliary basis for judging the effect of curtain grouting and optimizing construction parameters. Attached Figure Description

[0028] Figure 1 This is a flowchart of a construction method for assisting in the verification of the tunnel curtain grouting effect of the present invention.

[0029] Figure 2 A schematic diagram of the elevation section of the test borehole used for verifying grouting in the tunnel curtain.

[0030] Figure 3 This is a schematic diagram of the distribution of verification boreholes for curtain grouting on a tunnel cross section.

[0031] Figure 4 This is a schematic diagram of one distribution method of curtain grouting holes on a tunnel cross section.

[0032] Marked in the image: 1. Tunnel, 2. Working face, 3. Surrounding rock, 4. Verification borehole, 5. Grouting hole. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0034] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0035] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0036] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0037] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0038] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0039] Example This embodiment provides a construction method for auxiliary verification of the effect of tunnel curtain grouting.

[0040] This embodiment of the tunnel curtain grouting effect auxiliary verification construction method aims to solve the problems of existing curtain grouting effect verification methods, which are difficult to intuitively display the diffusion and filling state of grout in the surrounding rock pores, fissures and fracture zones, are not easy to detect local weak areas in a timely manner, and lack visual basis for dynamic optimization of grouting parameters. This method adds a fluorescent dyeing tracer to the grout, so that the solidified grout filling body has identifiable tracer marks. Then, optical images reflecting the distribution of the tracer marks are obtained by direct observation at the excavation face or by imaging inside the borehole, thereby intuitively judging the grouting effect and guiding supplementary grouting and parameter adjustment. The following describes the specific steps and... Figures 1 to 4 Please provide a detailed explanation.

[0041] Step 1: Determine the layout of the verification section and grouting holes 5 / verification probe holes 4 Based on advanced geological forecasts, geological sketches of the tunnel face 2, water inflow conditions, and the designed curtain grouting range, sections requiring auxiliary verification were identified. Verification targets included sand layers, silty fine sand interlayers, fault fracture zones, densely fractured zones, water-rich weak interlayers, and other strata where the grouting effect was not easily visually assessed. Verification methods could include excavation and revealing verification, borehole verification at the tunnel face 2, or a combination of both.

[0042] Simultaneously, based on the designed curtain grouting scheme and verification requirements, the layout of the curtain grouting holes 5 is determined, including the number of rows, spacing, depth, angle, and sequence of the grouting holes 5. For sections requiring subsequent borehole verification, the layout of the verification boreholes 4 is determined concurrently. The borehole locations should include at least one location within and outside the curtain grouting design outline, between the grouting holes 5, and near the water inflow point. The borehole depth and angle should be configured to cover the design reinforcement ring boundary and suspected weak areas, avoiding misjudgments of the grouting effect due to verification only near the grouting holes 5. For example... Figure 2 and Figure 3 The image shows one possible arrangement of the verification borehole 4 on the working face 2. Figure 4This is one arrangement of the grouting holes 5 on the working face 2. The grouting holes 5 can be concentrated in the upper half of the working face 2. The verification test holes 4 can be selected from the pre-drilled grouting holes 5 or dug separately. The diameter, depth, angle, and specific location of the test holes need to be determined comprehensively based on the surrounding rock conditions 3, grouting design parameters, and on-site construction conditions.

[0043] Step 2: Compatibility Test Based on advanced geological forecasts, geological sketches of the tunnel face 2, water inflow conditions, and the designed curtain grouting range, sections requiring auxiliary verification were identified. Verification targets included sand layers, silty fine sand interlayers, fault fracture zones, densely fractured zones, water-rich weak interlayers, and other strata where the grouting effect was not easily visually assessed. Verification methods could include excavation and revealing verification, borehole verification at the tunnel face 2, or a combination of both.

[0044] Before preparing the fluorescent tracer grout, a compatibility test should be conducted. A water-soluble, well-dispersible fluorescent dyeing tracer compatible with the intended grouting grout should be selected. The grouting grout can be a commonly used engineering grout such as cement grout, cement-water glass grout, ultrafine cement grout, or chemical grout. The tracer can be a single fluorescent agent or a mixture of a fluorescent agent and a common dyeing agent. The compatibility test should determine the effect of the fluorescent dyeing tracer on the grout's fluidity, setting time, bleeding rate, and the strength of the aggregate. Based on the test results, the type and amount of tracer to be added should be determined to ensure that design and construction requirements are met and to avoid potential grouting quality issues caused by tracer incompatibility with the grout.

[0045] Step 3: Prepare the fluorescent tracer slurry The grouting slurry is prepared according to the designed mix ratio. A fluorescent dyeing tracer is added to the slurry during the stirring process, and the mixture is thoroughly mixed to form a fluorescent tracer slurry. The fluorescent dyeing tracer is a water-soluble tracer that exhibits identifiable optical features under white light or excitation light and is compatible with the grouting slurry. The amount of tracer added is controlled at 0.001% to 0.5% of the slurry mass; the actual amount can be adjusted according to the color of the surrounding rock, the degree of groundwater dilution, the type of imaging light source, the type of slurry, and on-site environmental protection requirements. For example, in strata with darker surrounding rock and stronger groundwater dilution, the tracer concentration can be appropriately increased to ensure identification effectiveness; in light-colored surrounding rock or dry conditions, a lower concentration can be used. In a preferred embodiment, the amount of tracer added is 0.005% to 0.05% of the slurry mass.

[0046] After preparation, record the grout mix ratio, fluorescent staining tracer name or number, tracer color, tracer concentration, hole number, sequence, grouting time and cumulative grouting volume, and establish a grouting construction ledger and corresponding records of tracer marks for subsequent traceability.

[0047] Step 4: Perform curtain grouting to form tracer filling body Curtain grouting was performed on the section to be verified using prepared fluorescent tracer grout. Drilling, installation of borehole pipes, water pressure or inflow testing, segmented grouting, and borehole sealing were carried out according to the curtain grouting design. Under pressure, the fluorescent tracer grout entered the pores, fissures, and fracture zones of the surrounding rock 3 and solidified, forming a filling body with tracer markers. That is, the grout-bound stone body, filling zone, or grout vein retained identifiable fluorescent or stained features in the surrounding rock 3.

[0048] For multi-hole or multi-sequence curtain grouting, fluorescent tracers of different colors and concentrations are added to the grout corresponding to different hole locations or sequences. For example, the grout for the first sequence hole can be set with a yellow fluorescent tracer, and the grout for the second sequence hole can be set with a blue fluorescent tracer, or a red tracer can be used in the first round of grouting, and a green tracer can be used in the second round of replenishment. This creates tracer markers in the filling body that can distinguish the source and diffusion superposition relationship of the grout, facilitating subsequent tracking of the diffusion range and overlapping area of ​​grout from different hole locations and sequences, and providing a visual basis for optimizing the layout of grouting holes and the grouting sequence.

[0049] After grouting is completed, wait for the grout to initially set or reach a revealable strength, depending on the grout type and surrounding rock conditions. For cement-based grouts, revealing can be carried out after excavation safety and design requirements are met; for fast-setting grouts or cement-water glass two-component grouts, borehole verification can be carried out earlier depending on the setting time.

[0050] Step 5: Verification of Grouting Effect After the grout has solidified, the grouting effect will be verified. Verification methods include excavation reveal verification and borehole imaging verification at the working face, which can be used individually or in combination.

[0051] The specific method for excavation-based verification is as follows: When the excavation face 2 reaches the grouting reinforcement area, the excavation face, arch, sidewall, and slag samples of the grouting reinforcement area are illuminated with white light or excitation light. The excitation light can be ultraviolet or blue light to obtain optical images reflecting the distribution of tracer markers. By observing the distribution of fluorescent grout in the sand layer, fissures, and fractured zones, it can be intuitively determined whether the grout has reached and formed effective filling. To further eliminate interference from the natural color of the surrounding rock 3 or ambient light, the same location in the grouting reinforcement area can be illuminated or imaged using both white light and excitation light. The white light image and the excitation light image are then compared and identified to reduce the probability of misjudgment or missed judgment of tracer markers.

[0052] The specific method for verification by borehole exploration and in-hole imaging at face 2 is as follows: Boreholes are drilled at face 2 or the exposed face. The borehole locations should cover at least one of the following: inside and outside the curtain grouting design outline, between grouting holes 5, and near the water inflow point. The borehole depth and angle should be configured to cover the design reinforcement ring boundary and suspected weak areas, avoiding misjudgments due to verification only near grouting holes 5. An imaging probe with white light or excitation light supplementary illumination is inserted into the borehole. The imaging probe can be an in-hole video imager, in-hole television, borehole inspection instrument, or an imaging probe with white light and ultraviolet or blue light supplementary illumination. Images of the borehole wall are continuously acquired along the borehole depth to obtain optical images reflecting the distribution of tracer markers. The depth of grout diffusion, lateral coverage, and location of weak areas are determined by the location, continuous length, coverage angle, color intensity, and correspondence with fractures and sand layers in the images of fluorescent or dyed grout.

[0053] Step Six: Image Interpretation and Construction Feedback Excavation photos, borehole videos, or borehole television images are numbered and archived, and fluorescence distribution records can be generated using manual interpretation or image recognition methods. The grouting filling effect and weak areas are determined based on the continuity and coverage of tracer markers in the optical images, as well as the location of blank areas with missing tracer markers.

[0054] The criteria for judgment include at least one of the following: the depth of the tracer marker in the optical image, its continuous length, the coverage of the pore wall, the fissure filling rate, and the location of blank segments without tracer markers. For areas with continuous fluorescence, full distribution, and obvious fissure filling, it can be determined that the slurry has reached and formed effective filling; for areas with weak, intermittent, or no fluorescence, the presence of unfilled or weak areas should be determined by combining the water outflow, slab drop, sand collapse, and sampling conditions.

[0055] If insufficient fluorescence distribution, continuous blank areas, localized water inrush, or loose surrounding rock are found in the verification area, measures such as supplementary grouting, reducing hole spacing, adjusting grout concentration, increasing or decreasing grouting pressure, and adding inspection holes should be taken. When supplementing weak areas, add another fluorescent staining tracer with a different color or concentration than the fluorescent staining tracer used to form the original filling body to the supplementary grout. By verifying the grouting effect again, the distribution range of the original grout body and the supplementary grout body can be clearly distinguished, and it can be determined whether the supplementary grout has effectively entered the original unfilled area, thereby verifying the effectiveness of the supplementary grouting measures and providing a basis for adjusting the subsequent hole spacing, grouting pressure, and grout mix ratio. After the supplementary grouting is completed, the hole spacing, grout mix ratio, or grouting pressure of the subsequent curtain grouting should be further adjusted based on the verification results.

[0056] This method serves as an auxiliary verification and feedback optimization tool for grouting effect. The interpretation results should be used in conjunction with grouting parameters, changes in water output, geological sketches of the working face, advanced geological predictions, and conventional inspection hole test results to complement each other and improve the reliability of the comprehensive judgment of grouting effect.

[0057] Here are a few specific application examples.

[0058] Example 1 In the pre-grouting of water-rich fine sand layers, cement-water glass dual-liquid grout was used as the main grout. A green fluorescent tracer was added to the grout in sequence A holes at a rate of 0.02% of the grout mass; a blue fluorescent tracer was added to the grout in sequence B holes at a rate of 0.02% of the grout mass. After grouting was completed and the revealing conditions were met, the working face 2 was excavated to the verification mileage. A handheld UV or blue light source was used to irradiate working face 2 and the slag samples. If the sand layer between grouting holes 5 showed continuous fluorescent filling, and there was no obvious sand or water inflow at working face 2, the grout diffusion and filling in that area were considered good. If a local sand layer showed a non-fluorescent blank zone or significant water outflow, a supplementary grouting hole was added to that area, and a red fluorescent tracer was added to the supplementary grout to distinguish it from the initial grouting body.

[0059] Example 2 After the curtain grouting in the fault fracture zone is completed, exploratory boreholes are drilled at face 2 along the axis of tunnel 1 and the outer corner of the arch, with the borehole depth covering the outer boundary of the designed reinforcement ring. An in-hole television probe equipped with ultraviolet or blue light supplementary illumination is inserted into the borehole to continuously acquire images of the borehole wall. If fluorescent grout veins are visible within the borehole wall fissures and appear continuously within the designed reinforcement ring, it indicates that the grout has entered the fissures and formed a filling. If fluorescence is intermittent or absent within a certain depth range of the borehole, accompanied by water seepage, this depth range is designated as a reinforcement focus. A fluorescent staining tracer with a different color than the original tracer is used in the replenished grout for verification.

[0060] Example 3 In two rounds of curtain grouting at the same working face, the first round used a yellow fluorescent tracer, with an addition amount of 0.01% of the grout mass; the second round used a red fluorescent tracer, with an addition amount of 0.015% of the grout mass. Through excavation and borehole imaging, the first round of grouting and the subsequent grouting could be clearly distinguished, determining whether the grouting had entered the previously unfilled area. If the red tracer mark appeared in the blank area of ​​the original yellow tracer mark, it proved that the grouting effectively covered the weak area, thus allowing for optimization of subsequent borehole spacing, grouting pressure, and grout mix ratio.

[0061] In summary, this invention provides a construction method for auxiliary verification of tunnel curtain grouting effects. By adding a fluorescent dyeing tracer with identifiable optical characteristics under white light or excitation light to the grout, the grout solidifies in the pores, fissures, and fractured zones of the surrounding rock to form a filling body with tracer marks, thus visualizing the diffusion and filling status of the grout. By illuminating the excavation face with white light or excitation light, and / or by drilling exploratory holes and combining them with an imaging probe with supplemental lighting to acquire images of the hole walls, the optical characteristics reflecting the distribution of the tracer marks can be directly obtained. The image, based on the distribution continuity, coverage, and blank area location of the tracer markers, accurately determines the grouting filling effect and weak areas, and performs supplementary grouting on weak areas, and / or adjusts the hole spacing, grout mix ratio, or grouting pressure of subsequent curtain grouting. This solves the technical problems of existing curtain grouting effect verification methods, which are difficult to intuitively display the grout diffusion and filling status, are not easy to detect local weak areas in a timely manner, and lack visual basis for dynamic optimization of grouting parameters. It provides a direct and reliable auxiliary basis for judging the effect of curtain grouting and optimizing construction parameters.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A construction method for auxiliary verification of the effect of tunnel curtain grouting, characterized in that, Includes the following steps: S1: Add the fluorescent staining tracer to the grouting slurry and mix evenly to prepare the fluorescent tracer slurry; the fluorescent staining tracer can exhibit identifiable optical features under white light or excitation light irradiation and is compatible with the grouting slurry; S2: Use the fluorescent tracer slurry to perform curtain grouting on the section to be verified, so that the fluorescent tracer slurry enters the pores, fissures and / or fracture zones of the surrounding rock (3) and solidifies to form a filling body with tracer markers; S3: After the grout has solidified, verify the grouting effect: Irradiate the excavation face of the grouting reinforcement area with white light or excitation light, and / or drill a probe hole at the working face (2), and send an imaging probe with white light or excitation light supplementary light function into the probe hole to collect the hole wall image and obtain an optical image reflecting the distribution of the tracer mark. S4: Based on the continuity of the distribution of tracer marks in the optical image, the coverage area, and the location of blank areas with missing tracer marks, determine the grouting filling effect and weak areas, and supplement the weak areas with grouting, and / or adjust the hole spacing, grout ratio, or grouting pressure of subsequent curtain grouting.

2. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, The fluorescent staining tracer is a water-soluble tracer, and the amount of the fluorescent staining tracer added is 0.001% to 0.5% of the slurry mass.

3. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, The grouting slurry is cement slurry, cement-water glass slurry, or chemical slurry.

4. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In S2, for porous or multi-sequence grouting, fluorescent staining tracers with different colors and / or different concentrations are added to the grouting slurry corresponding to different pore positions or different sequences, so as to form tracer marks in the filling body that can distinguish the source of slurry and the diffusion superposition relationship.

5. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In S3, the same location in the grouting reinforcement area is subjected to dual-mode irradiation or imaging acquisition using white light and excitation light respectively, and the white light image and excitation light image are compared and identified.

6. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In S3, when drilling exploratory holes at the working face (2), the exploratory hole locations include at least one of the following: inside and outside the curtain grouting design outline, between grouting holes (5), and near the water inflow point. The depth and angle of the exploratory holes are configured to cover the design reinforcement ring boundary and suspected weak areas.

7. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In S4, the indicators used to determine the grouting filling effect and weak areas include at least one of the following: the depth of the tracer mark in the optical image, its continuous length, the hole wall coverage, the crack filling rate, and the location of the blank segment without a tracer mark.

8. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In S4, before filling the weak area, another fluorescent staining tracer with a different color or concentration than the fluorescent staining tracer that forms the filling body is added to the filling grout, and the entry range of the filling grout is determined by verifying the grouting effect again.

9. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, In step S1, before adding the fluorescent dyeing tracer to the grout, the following steps are also included: conducting a compatibility test to determine the effect of the fluorescent dyeing tracer on the grout fluidity, setting time, bleeding rate and stone strength, and determining the type and amount of tracer to be added based on the test results.

10. The construction method for auxiliary verification of tunnel curtain grouting effect according to claim 1, characterized in that, S2 also includes: after the grout is prepared, establishing a corresponding record of the grouting construction ledger and the tracer mark; wherein, the record includes the hole number, sequence, grouting time, grouting pressure, cumulative grouting volume, fluorescent dye tracer name or number, tracer color and tracer concentration.

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