Non-equilibrium grouting method based on multi-dimensional characteristics of tunnel rock mass

Abstract

According to the non-equilibrium grouting method based on the multi-dimensional characteristics of the tunnel rock mass, accurate and intelligent grouting control over the complex fractured rock mass of the tunnel is achieved by constructing a technical system integrating multi-dimensional geologic characteristic recognition and modeling decision. Firstly, according to the gap width, connectivity and filling state, cracks are comprehensively classified, spatial distribution data are formed, geological conditions are converted into structured and spatially locatable digital information, and an accurate target object is provided for grouting construction. And furthermore, through the grouting parameter decision model, the current fracture type is automatically mapped into a grout proportion, grouting pressure and grouting rate combination which are strictly matched with the current fracture type, and intelligent and standardized decision from geological features to construction parameters is realized. According to the process, mature experience and theoretical cognition are solidified into a rule capable of being repeatedly executed, it is ensured that the initial construction scheme is highly matched with the inherent hydraulic characteristics of the fractures, and therefore the pertinence and controllability of grouting construction are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of tunnel rock mass feature monitoring and processing technology, specifically to a non-equilibrium grouting method based on multi-dimensional features of tunnel rock mass. Background Technology

[0002] In tunnel engineering, fissures are a common geological feature as rock mass is excavated. Different fissures exhibit significant differences in scale, connectivity, and filling state, forming a complex fissure network with strong anisotropy. Therefore, grouting is necessary to improve the rock mass's mechanical properties and enhance its seepage prevention capabilities. However, traditional equilibrium grouting methods treat the entire rock mass as a homogeneous body, employing uniform grout mix ratios, grouting pressures, and termination criteria, neglecting the anisotropy of the fissure system. This approach stems from limitations in its underlying technical framework: in terms of "perception," it relies solely on grouting pressure and flow rate data, lacking monitoring of rock mass deformation, grout behavior within fissures, and material conditions; in terms of "decision-making," it cannot accurately diagnose and classify fissure types and grouting states based on multi-dimensional information; and in terms of "execution," it struggles to achieve real-time, interconnected, and adaptive matching of grout performance, process parameters, and operating conditions. Based on the cubic law, the permeability of a crack is proportional to the cube of its width. This leads to many drawbacks of traditional uniform grouting: for micro-cracks with a width of <0.5mm, the grout viscosity is high and the grouting pressure is insufficient, making it difficult to inject effectively and leaving leakage channels; for medium-sized cracks of 0.5~5mm, it is impossible to balance the grouting efficiency and diffusion range, affecting the quality; for wide cracks >5mm, the grout is prone to excessive loss, resulting in material waste and difficulty in establishing effective pressure.

[0003] Existing grouting methods have three major limitations: First, they rely solely on manual judgment based on pressure and flow rate data, failing to comprehensively and quantitatively capture multi-dimensional state information such as grout pressure, rock micro-strain, and grout temperature within the fractures. This leads to unclear understanding of grout diffusion and rock mass response, resulting in delayed and inaccurate dynamic adjustments that can easily cause safety hazards. Second, they typically only classify grouting based on fracture width, without fully considering geological attributes such as fracture connectivity and filling status, and without relating it to special conditions such as high stress, rock mass deformation, and low-temperature environments. This causes the grouting scheme to be out of touch with complex geological scenarios, resulting in insufficient adaptability. Third, grout mix ratio adjustment, grouting parameter control, and process mode switching are disconnected, relying on manual, step-by-step operations, and failing to form an adaptive adjustment and optimization based on real-time feedback. Summary of the Invention

[0004] The main objective of this invention is to provide a non-equilibrium grouting method based on the multi-dimensional characteristics of tunnel rock mass, in order to solve the technical problems of existing technologies failing to systematically integrate multi-dimensional geological features with the spatial distribution of fractures and intelligently generate differentiated grouting parameters, resulting in insufficient adaptability of the formulated grouting scheme to complex geological conditions and poor controllability of the grouting process.

[0005] To achieve the above objectives, the present invention provides a non-equilibrium grouting method based on the multi-dimensional characteristics of tunnel rock mass, comprising the following steps: S1. Obtain geological exploration data of the construction tunnel, determine the width, connectivity, and filling state of the fissures based on the geological exploration data, and then classify the fissures according to the width, connectivity, and filling state to obtain various fissure types, thereby forming spatial distribution data of fissure types; wherein, the geological exploration data includes spatial distribution data of each fissure in the rock mass of the construction tunnel. S2. Obtain the location of the crack to be grouted within the construction tunnel, determine the current crack type based on the location and the spatial distribution data of the crack type, and formulate a construction plan based on the current crack type; wherein, the construction plan includes grouting construction; S3. Obtain a pre-established grouting parameter decision model, input the current crack type into the grouting parameter decision model to obtain the grouting parameter combination corresponding to the current crack type, and use the grouting parameter combination to perform grouting construction on the current crack to be grouted; wherein, the grouting parameter decision model includes the mapping relationship between crack type and grouting parameter combination, and the grouting parameter combination includes grout mix ratio parameters, grouting pressure and grouting rate.

[0006] Furthermore, in step S1, the fractures are classified into various fracture types based on their width, connectivity, and filling state, specifically including the following steps: Based on the numerical range of the crack width, the crack level is divided into micro cracks, medium cracks, and large cracks; wherein, cracks with a crack width of less than 0.5 mm are classified as micro cracks, cracks with a crack width of 0.5 mm to 5 mm are classified as medium cracks, and cracks with a crack width of more than 5 mm are classified as large cracks. The permeability coefficient of the fracture is obtained, and the connectivity level of the fracture is divided into high connectivity, medium connectivity and low connectivity based on the permeability coefficient; wherein, the fracture with a permeability coefficient greater than 10 Lu is classified as high connectivity, the fracture with a permeability coefficient between 1 Lu and 10 Lu is classified as medium connectivity, and the fracture with a permeability coefficient less than 1 Lu is classified as low connectivity. The characteristics of the filling material in the fracture are obtained, and the filling state of the fracture is divided into empty fracture, muddy filling fracture and rock debris filling fracture based on the characteristics of the filling material. The width level, connectivity level, and filling state of each fracture are combined to form a multi-dimensional composite fracture type defined by the width level, connectivity level, and filling state; wherein the width level and connectivity level are correlated.

[0007] More preferably, the step S2 of formulating a construction plan based on the current fracture type specifically includes the following steps: The construction plan also includes a pretreatment process, which is determined based on the filling state of the current crack to be grouted; wherein; When the filling state is muddy filling or rock cuttings filling, the determined pretreatment process is to use a fluid jet with a pressure higher than 5MPa to remove the filling material in the fracture. When the filling state is an empty crack, no pretreatment is performed.

[0008] As a further preferred embodiment, the grouting parameter decision model in step S3 includes establishing a correspondence between the grouting parameter combination and at least the crack width level and connectivity level in the current crack type, specifically including: When the current fracture type has a width level of wide fracture and a connectivity level of high connectivity, the grouting parameter combination includes: using fast-setting grout mixed with aggregate or cement-water glass grout, matching the grouting pressure to less than 1MPa, matching the grouting rate to no more than 30L / min, and setting the grouting method to intermittent grouting mode. When the current fracture type has a fracture width level of medium fracture and a connectivity level of medium connectivity, the grouting parameter combination includes: using conventional cement-based grout, with the grout concentration varying in a stepwise manner from thin to thick water-cement ratio of 5:1, 3:1, 2:1, 1:1, and 0.5:1, matching the grouting pressure to 1MPa to 3MPa, and matching the grouting rate to 10L / min to 30L / min; When the current fracture type has a width level of micro fracture and a connectivity level of low connectivity, the grouting parameter combination includes: using a stable grout, matching the grouting pressure to be higher than 3MPa, and matching the grouting rate to be lower than 10L / min.

[0009] More preferably, after step S3, the following steps are also included: S4. Collect real-time response data of the current fracture; wherein, the real-time response data includes grout seepage pressure data, grout seepage data, rock mass micro-strain data and grout temperature within the fracture; Specifically, it includes: By pre-deploying micro-strain sensors in the rock mass surrounding the current crack to be grouted, the micro-strain data of the rock mass reflecting the deformation of the rock mass structure is continuously collected. The grout pressure data, which reflects the fluid pressure of the grout inside the fracture space, is collected by a pressure sensor installed at the grouting hole or extending into the fracture. The slurry seepage data, which reflects the volume of slurry flowing through the flow meter per unit time, is collected by a flow meter installed inside the fissure. The temperature data of the slurry, which reflects the hydration reaction state of the slurry or the ambient temperature, is collected by a temperature sensor that contacts the slurry. The rock mass microstrain data, the grout seepage pressure data within the fracture, the grout seepage data, and the grout temperature data are collected and recorded in a time-synchronized manner to form a multi-dimensional monitoring data sequence with temporal correlation as the real-time response data of the current fracture.

[0010] Furthermore, the following steps are included after step S4: S5. Obtain the pre-established grouting parameter correction model, input the real-time response data into the grouting parameter correction model to obtain the real-time working condition type of the current crack; determine whether there is an abnormal working condition type; if so, correct the grouting parameter combination in real time according to the abnormal working condition type to obtain the corrected grouting parameter combination, and then return to step S4 until the grouting construction is completed; wherein, the grouting parameter correction model includes the mapping relationship between real-time response data, abnormal working condition type and grouting parameter combination.

[0011] More preferably, in step S5, the real-time response data is input into the grouting parameter correction model to obtain the real-time working condition type of the current fracture and determine whether there is an abnormal working condition type. This specifically includes the following steps: The grouting parameter correction model includes predetermined criteria rules. The real-time response data determines the real-time working condition type of the current fracture through the predetermined criteria rules, and determines whether there are abnormal working condition types. The predetermined criteria rules include the mapping relationship between real-time response data and real-time working condition types. The abnormal working condition types include wide fracture loss working condition, micro-fracture blockage working condition, and rock mass deformation early warning working condition.

[0012] More preferably, the predetermined criterion rule includes: When the grout seepage pressure data in the fissure is continuously lower than the first pressure threshold, the grout seepage data is continuously higher than the first flow rate threshold, and the rate of change of the rock mass microstrain data is lower than the first strain rate threshold, it is determined to be the wide fissure loss condition. When the grouting pressure is continuously higher than the second pressure threshold, the grouting rate is continuously lower than the second flow rate threshold, and the rate of change of the grout temperature data is lower than the temperature change rate threshold, it is determined to be the micro-crack blockage condition. When the value of the micro-strain data of the rock mass exceeds the preset strain warning threshold or its rate of change exceeds the preset rate of change warning threshold, it is determined to be a rock mass deformation warning condition.

[0013] More preferably, step S5 involves real-time correction of the grouting parameter combination based on the abnormal working condition type to obtain the corrected grouting parameter combination, specifically including the following steps: The grouting parameter correction model also includes a preset correction strategy. Based on the abnormal working condition type, the preset correction strategy determines a correction instruction set corresponding to the abnormal working condition type, and executes the correction instruction set to correct the grouting parameter combination in real time, resulting in a corrected grouting parameter combination. The preset correction strategy includes a mapping relationship between the abnormal working condition type and the correction instruction set, and the correction instruction set includes instructions for coordinating the adjustment of one or more parameters among the grout mix ratio, grouting pressure, and grouting rate.

[0014] More preferably, the correction instruction set includes: The set of correction instructions corresponding to the wide crack loss condition includes instructions to increase the grout viscosity and / or add a quick-setting agent, instructions to reduce the grouting pressure setting value and / or the grouting rate setting value, and instructions to switch the grouting mode to intermittent grouting mode. The set of correction instructions corresponding to the micro-crack blockage condition includes instructions to reduce grout viscosity and / or add water-reducing agent, as well as instructions to switch the grouting mode to pulse grouting mode; The set of correction instructions corresponding to the rock mass deformation early warning condition includes instructions to reduce the grouting pressure setting value and / or the grouting rate setting value.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention achieves precise and intelligent grouting control for complex fractured rock masses in tunnels by constructing a technical system that integrates multi-dimensional geological feature recognition and model-based decision-making. First, fractures are comprehensively classified based on their width, connectivity, and filling state, generating spatial distribution data. This transforms geological conditions into structured, spatially locatable digital information, providing precise target objects for grouting construction. Then, through a grouting parameter decision model, the current fracture type is automatically mapped to a strictly matching combination of grout mix ratio, grouting pressure, and grouting rate, achieving intelligent and standardized decision-making from geological features to construction parameters. This process solidifies mature experience and theoretical understanding into repeatable rules, ensuring a high degree of compatibility between the initial construction plan and the inherent hydraulic characteristics of the fractures, thereby significantly improving the targeting and controllability of grouting construction. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the process of an unbalanced grouting method based on the multi-dimensional characteristics of tunnel rock mass according to an embodiment of the present invention.

[0018] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0022] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0023] Please see Figure 1 This embodiment provides a non-uniform grouting method based on the multi-dimensional characteristics of tunnel rock mass, including the following steps: S1. Obtain geological exploration data of the construction tunnel, determine the width, connectivity, and filling state of the fissures based on the geological exploration data, and then classify the fissures according to the width, connectivity, and filling state to obtain various fissure types, thereby forming spatial distribution data of fissure types; wherein, the geological exploration data includes spatial distribution data of each fissure in the rock mass of the construction tunnel. S2. Obtain the location of the crack to be grouted within the construction tunnel, determine the current crack type based on the location and the spatial distribution data of the crack type, and formulate a construction plan based on the current crack type; wherein, the construction plan includes grouting construction; S3. Obtain a pre-established grouting parameter decision model, input the current crack type into the grouting parameter decision model to obtain the grouting parameter combination corresponding to the current crack type, and use the grouting parameter combination to perform grouting construction on the current crack to be grouted; wherein, the grouting parameter decision model includes the mapping relationship between crack type and grouting parameter combination, and the grouting parameter combination includes grout mix ratio parameters, grouting pressure and grouting rate.

[0024] This embodiment achieves refined and adaptive grouting of complex fracture networks in tunnel rock masses by constructing a complete closed-loop control process from multi-dimensional geological feature identification to dynamic regulation of the grouting process. First, fractures are structurally classified based on their width, connectivity, and filling state, transforming geological exploration data into spatial distribution data of fracture types that can directly guide construction, enabling the initial construction plan to accurately match the heterogeneity of the rock mass. Second, the grouting parameter decision model automatically generates corresponding grouting parameter combinations based on the current fracture type, achieving quantitative and intelligent decision-making from geological features to construction technology.

[0025] This embodiment reduces grout waste in wide fissures by selecting differentiated materials and processes, while ensuring effective grouting of micro-fissures, thus improving grouting efficiency. Data monitoring allows for scientific adjustment of grouting parameters, reducing rework costs caused by human error, and targeted supplementary grouting effectively saves materials and lowers subsequent operation and maintenance costs. By precisely matching grouting schemes to the characteristics of fissures with different widths, a continuous and complete seepage-proof curtain and reinforced body are formed, significantly improving grouting quality and avoiding engineering risks such as rock mass uplift and splitting caused by blind high-pressure grouting. Real-time dynamic monitoring allows for timely avoidance of abnormal problems.

[0026] In this embodiment, step S1 further classifies the fractures according to their width, connectivity, and filling state to obtain various fracture types, specifically including the following steps: Based on the numerical range of the crack width, the crack level is divided into micro cracks, medium cracks, and large cracks; wherein, cracks with a crack width of less than 0.5 mm are classified as micro cracks, cracks with a crack width of 0.5 mm to 5 mm are classified as medium cracks, and cracks with a crack width of more than 5 mm are classified as large cracks. In this embodiment, the micro-cracks have poor permeability and high flow resistance, resulting in poor groutability; the medium-sized cracks have good groutability, but it is necessary to pay attention to balancing grouting efficiency and grout diffusion range; the wide cracks have strong permeability, but grout loss is serious and pressure is difficult to establish effectively.

[0027] This embodiment obtains the permeability coefficient of the fractures based on a water pressure test, and classifies the connectivity level of the fractures into high connectivity, medium connectivity, and low connectivity according to the permeability coefficient; wherein, fractures with a permeability coefficient greater than 10 Lu are classified as high connectivity, fractures with a permeability coefficient between 1 Lu and 10 Lu are classified as medium connectivity, and fractures with a permeability coefficient less than 1 Lu are classified as low connectivity. In this embodiment, the characteristics of the filling material in the fracture are obtained by using borehole television and core sample analysis. Based on the characteristics of the filling material, the filling state of the fracture is divided into empty fracture, muddy filling fracture and rock cuttings filling fracture. The width level, connectivity level, and filling state of each fracture are combined to form a multi-dimensional composite fracture type defined by the width level, connectivity level, and filling state. The width level and connectivity level are correlated. In actual engineering, the correlation between the width level and connectivity level means that wide fractures are often associated with high connectivity, medium fractures with medium connectivity, and micro fractures with low connectivity.

[0028] More preferably, the step S2 of formulating a construction plan based on the current fracture type specifically includes the following steps: The construction plan also includes a pretreatment process, which is determined based on the filling state of the current crack to be grouted; wherein; When the filling state is muddy filling or rock cuttings filling, the determined pretreatment process is to use a fluid jet with a pressure higher than 5MPa to remove the filling material in the fracture. When the filling state is an empty crack, no pretreatment is performed.

[0029] For example, when the current fracture type is wide fracture with high connectivity and filled with mud, the proposed construction plan is to first use high-pressure water to flush away the mud, and then inject sand-mixed fast-setting grout. When the current fracture type is micro-fracture with low connectivity and voids, the proposed construction plan is to first vacuum-pre-extract the fracture to be grouted, and then use low-viscosity materials such as ultrafine silicate cement for grouting under high pressure and slow speed to avoid bleeding and blockage. The ultrafine silicate cement refers to a hydraulic cementitious material with a relatively fine particle size, made by grinding silicate cement clinker with an appropriate amount of gypsum and specified mixed materials.

[0030] More preferably, the grouting parameter decision model in step S3 includes establishing a correspondence between the grouting parameter combination and at least the crack width level and connectivity level in the current crack type, specifically including: When the current fracture type has a width level of wide fracture and a connectivity level of high connectivity, the grouting parameter combination includes: using fast-setting grout mixed with aggregate or cement-water glass grout, matching the grouting pressure to less than 1MPa, matching the grouting rate to no more than 30L / min, and setting the grouting method to intermittent grouting mode. When the current fracture type has a medium fracture width and a medium connectivity, the grouting parameter combination includes: using conventional cement-based grout, with the grout concentration varying in stages from thin to thick according to water-cement ratios of 5:1, 3:1, 2:1, 1:1, and 0.5:1; matching the grouting pressure to 1 MPa to 3 MPa; and matching the grouting rate to 10 L / min to 30 L / min. Medium grouting pressure is used to match a medium grouting flow rate to control the diffusion radius. In principle, the higher the grouting pressure, the farther the grout diffuses in the rock mass, and the better the grouting effect. When the current fracture type has a width level of micro-fracture and a connectivity level of low connectivity, the grouting parameter combination includes: using a stable grout, matching the grouting pressure to a value higher than 3 MPa, and matching the grouting rate to a value lower than 10 L / min. The stable grout is a grout that can be stored at room temperature and pressure for a relatively long time without changing its basic properties. According to the definition in DL / T5148-2021, 3.2.5, it refers to a cement grout containing a stabilizer and having a 2-hour water separation rate of no more than 5%.

[0031] In this embodiment, the rules for the current fracture type and grouting parameter combination are systematically summarized, organized, and encoded, and entered into a computer database or configuration file to form a grouting parameter decision model that can be queried and invoked from the computer database or configuration file. The grouting parameter decision model automatically retrieves matching rules based on the input fracture type and outputs the corresponding grouting parameter combination.

[0032] In one embodiment, the grouting of tunnel fissures follows a zoned and sequential grouting approach, starting with wider fissures and gradually narrowing them. Specifically, the grouting follows the sequence of first sealing wide fissures, then grouting medium-sized fissures, and finally penetrating micro-fissures. For example, for medium-sized fissures, a sequential grouting process is used, starting with thin grout and gradually increasing its thickness; for micro-fissures, a high-pressure, slow-rate continuous grouting method is employed. Simultaneously, multi-parameter sensors are deployed, with micro-strain sensors corresponding to the grouting hole sequence, and fissure seepage pressure sensors and grout temperature sensors installed at the hole openings. Sensor data is collected every 10 seconds and displayed in real time, with particular attention paid to the grouting pressure-grouting flow rate curve. The zoning and sequential approach refers to dividing the grouting area into multiple zones, with each zone's grouting holes further divided into several sequences for grouting. For example, the area can be divided into zones based on engineering geological characteristics (such as the width of the fissures; for example, if a zone consists of wide, open fissures, then it is classified as a zone). The order of grouting is based on the number of grouting holes, generally grouting the odd-numbered holes first, and then grouting the even-numbered holes.

[0033] In one embodiment, the grouting construction sequence is further optimized: based on borehole CT imaging to identify key control sections in the spatial distribution data of fractures, such as cross fractures and the middle section of long fractures, which are core locations that affect the grout diffusion range, the grouting holes corresponding to the key control sections are grouted first, and the grouting pressure is set higher than that of ordinary grouting holes. Then, the construction is carried out in the order of extending outward from the key control sections to reduce the disorderly loss of grout in the complex network.

[0034] In one embodiment, the following steps are included after step S3: S4. Collect real-time response data of the current fracture; wherein, the real-time response data includes grout seepage pressure data, grout seepage data, rock mass micro-strain data and grout temperature within the fracture; Specifically, it includes: By pre-deploying micro-strain sensors in the rock mass surrounding the current crack to be grouted, the micro-strain data of the rock mass reflecting the deformation of the rock mass structure is continuously collected. The grout pressure data, which reflects the fluid pressure of the grout inside the fracture space, is collected by a pressure sensor installed at the grouting hole or extending into the fracture. The slurry seepage data, which reflects the volume of slurry flowing through the flow meter per unit time, is collected by a flow meter installed inside the fissure. The temperature data of the slurry, which reflects the hydration reaction state of the slurry or the ambient temperature, is collected by a temperature sensor that contacts the slurry. The rock mass microstrain data, the grout seepage pressure data within the fracture, the grout seepage data, and the grout temperature data are collected and recorded in a time-synchronized manner to form a multi-dimensional monitoring data sequence with temporal correlation as the real-time response data of the current fracture.

[0035] In one embodiment, step S4 is followed by the following step: S5. Obtain the pre-established grouting parameter correction model, input the real-time response data into the grouting parameter correction model to obtain the real-time working condition type of the current crack; determine whether there is an abnormal working condition type; if so, correct the grouting parameter combination in real time according to the abnormal working condition type to obtain the corrected grouting parameter combination, and then return to step S4 until the grouting construction is completed; wherein, the grouting parameter correction model includes the mapping relationship between real-time response data, abnormal working condition type and grouting parameter combination.

[0036] In this embodiment, step S5 further includes inputting the real-time response data into the grouting parameter correction model to obtain the real-time working condition type of the current crack and determine whether there is an abnormal working condition type. Specifically, this includes the following steps: The grouting parameter correction model includes predetermined criteria rules. The real-time response data determines the real-time working condition type of the current fracture through the predetermined criteria rules, and determines whether there are abnormal working condition types. The predetermined criteria rules include the mapping relationship between real-time response data and real-time working condition types. The abnormal working condition types include wide fracture loss working condition, micro-fracture blockage working condition, and rock mass deformation early warning working condition.

[0037] During grouting, multi-dimensional real-time response data, including grout pressure, grout flow, rock mass micro-strain, and grout temperature, are collected simultaneously, providing a data foundation for comprehensive perception of the process status. Furthermore, the grouting parameter correction model analyzes the real-time response data to determine the current working condition and adjusts the grouting parameter combination online and in a coordinated manner, forming a real-time closed-loop control from perception and diagnosis to real-time adjustment. This allows the grouting process to dynamically adapt to the constantly changing flow and mechanical conditions within the fractures, significantly improving the overall targeting, controllability, and final project quality of the grouting.

[0038] In this embodiment, the predetermined criterion rule further includes: When the grout seepage pressure data in the fissure is continuously lower than the first pressure threshold, the grout seepage data is continuously higher than the first flow rate threshold, and the rate of change of the rock mass microstrain data is lower than the first strain rate threshold, it is determined to be the wide fissure loss condition. When the grouting pressure is continuously higher than the second pressure threshold, the grouting rate is continuously lower than the second flow rate threshold, and the rate of change of the grout temperature data is lower than the temperature change rate threshold, it is determined to be the micro-crack blockage condition. When the value of the micro-strain data of the rock mass exceeds the preset strain warning threshold or its rate of change exceeds the preset rate of change warning threshold, it is determined to be a rock mass deformation warning condition.

[0039] In this embodiment, more preferably, step S5 involves real-time correction of the grouting parameter combination based on the abnormal working condition type to obtain the corrected grouting parameter combination, specifically including the following steps: The grouting parameter correction model also includes a preset correction strategy. Based on the abnormal working condition type, the preset correction strategy determines a correction instruction set corresponding to the abnormal working condition type, and executes the correction instruction set to correct the grouting parameter combination in real time, resulting in a corrected grouting parameter combination. The preset correction strategy includes a mapping relationship between the abnormal working condition type and the correction instruction set, and the correction instruction set includes instructions for coordinating the adjustment of one or more parameters among the grout mix ratio, grouting pressure, and grouting rate.

[0040] Specifically, the correction instruction set includes: The correction instruction set corresponding to the wide fracture loss condition includes instructions to increase grout viscosity and / or add accelerators, instructions to decrease the grouting pressure setting and / or grouting rate setting, and instructions to switch the grouting mode to intermittent grouting mode. In this embodiment, the intermittent grouting mode is a special grouting process, referring to a grouting method in which grout is injected into the formation (such as rock fractures or soil pores) in stages, with intervals and controlled pauses. Through active rhythm control, the problem of loss of control that easily occurs in continuous grouting under complex geological conditions is solved.

[0041] The set of correction instructions corresponding to the micro-crack blockage condition includes instructions to reduce grout viscosity and / or add water-reducing agent, as well as instructions to switch the grouting mode to pulse grouting mode; The set of correction instructions corresponding to the rock mass deformation early warning condition includes instructions to reduce the grouting pressure setting value and / or the grouting rate setting value.

[0042] In one embodiment, when the construction tunnel is located in a high-altitude and cold region, the following steps are included before step S3: The formation temperature data of the tunnel under construction is obtained, and when the grouting parameter decision model generates the grouting parameter combination, it determines whether the formation temperature data is lower than a preset low temperature threshold. When the formation temperature data is lower than the preset low temperature threshold, a slurry formula containing a quick-setting agent is matched to the slurry ratio parameters.

[0043] This embodiment employs geological mapping and geophysical exploration to comprehensively investigate the rock geological conditions of the tunnel construction area, preliminarily predicting the spatial distribution and approximate size of fractures. Based on regional geological data, the connectivity levels of the fractures are preliminarily classified. In high-altitude and cold regions, additional investigations are conducted to determine ground temperature data for the tunnel construction area, providing a basis for grout mix design. This embodiment first constructs exploratory boreholes: exploratory boreholes are constructed in the pre-determined area to obtain rock core samples. Using borehole television, CT, and water pressure testing techniques, the specific location, width, and extension of fractures are accurately identified, with a focus on locating large fractures. The fracture filling state and connectivity are precisely identified: the color (grayish-brown for muddy materials, grayish-white for rock fragments) and adhesion state of the filling material within the fractures are observed through borehole television, and the filling type is determined based on the degree of core sample fragmentation; the permeability coefficient Lu value is calculated through water pressure testing to clarify the connectivity level. In high-altitude and cold regions, the exploratory boreholes are immediately sealed after construction to prevent water accumulation and freezing from affecting subsequent grouting.

[0044] In one embodiment, changes in grouting pressure and flow rate can be monitored in real time, and the pressure-flow-time relationship curve can be recorded. If the grouting pressure is low and the grouting flow rate is high and does not decrease, it is determined that there are unidentified wide fissures, and the system is immediately switched to a fast-setting, intermittent grouting scheme. If the grouting pressure rises steadily and the grouting flow rate decreases steadily, it is determined that the medium-sized fissures are being filled normally, and the grout concentration is maintained or adjusted. If the grouting pressure is high and the grouting flow rate is low, it is determined that there are micro-fissures or channel blockages, and a finer grout material is used or the pressure is appropriately increased. After construction is completed, inspection holes are set up for water pressure tests to test the seepage prevention performance of the rock mass and the grouting effect. If the water pressure test fails, a supplementary grouting plan is developed for the areas where the grouting effect is substandard, and targeted supplementary grouting is implemented. After the supplementary grouting is completed, the effect is checked again until it is qualified.

[0045] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass, characterized in that, Includes the following steps: S1. Obtain geological exploration data of the construction tunnel, determine the width, connectivity, and filling state of the fissures based on the geological exploration data, and then classify the fissures according to the width, connectivity, and filling state to obtain various fissure types, thereby forming spatial distribution data of fissure types; wherein, the geological exploration data includes spatial distribution data of each fissure in the rock mass of the construction tunnel. S2. Obtain the location of the crack to be grouted within the construction tunnel, determine the current crack type based on the location and the spatial distribution data of the crack type, and formulate a construction plan based on the current crack type; wherein, the construction plan includes grouting construction; S3. Obtain a pre-established grouting parameter decision model, input the current crack type into the grouting parameter decision model to obtain the grouting parameter combination corresponding to the current crack type, and use the grouting parameter combination to perform grouting construction on the current crack to be grouted; wherein, the grouting parameter decision model includes the mapping relationship between crack type and grouting parameter combination, and the grouting parameter combination includes grout mix ratio parameters, grouting pressure and grouting rate.

2. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 1, characterized in that, Step S1 classifies fractures into various fracture types based on their width, connectivity, and filling state, specifically including the following steps: Based on the numerical range of the crack width, the crack level is divided into micro cracks, medium cracks, and large cracks; wherein, cracks with a crack width of less than 0.5 mm are classified as micro cracks, cracks with a crack width of 0.5 mm to 5 mm are classified as medium cracks, and cracks with a crack width of more than 5 mm are classified as large cracks. The permeability coefficient of the fracture is obtained, and the connectivity level of the fracture is divided into high connectivity, medium connectivity and low connectivity based on the permeability coefficient; wherein, the fracture with a permeability coefficient greater than 10 Lu is classified as high connectivity, the fracture with a permeability coefficient between 1 Lu and 10 Lu is classified as medium connectivity, and the fracture with a permeability coefficient less than 1 Lu is classified as low connectivity. The characteristics of the filling material in the fracture are obtained, and the filling state of the fracture is divided into empty fracture, muddy filling fracture and rock debris filling fracture based on the characteristics of the filling material. The width level, connectivity level, and filling state of each fracture are combined to form a multi-dimensional composite fracture type defined by the width level, connectivity level, and filling state; wherein the width level and connectivity level are correlated.

3. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 2, characterized in that, Step S2, which describes developing a construction plan based on the current fracture type, specifically includes the following steps: The construction plan also includes a pretreatment process, which is determined based on the filling state of the current crack to be grouted; wherein; When the filling state is muddy filling or rock cuttings filling, the determined pretreatment process is to use a fluid jet with a pressure higher than 5MPa to remove the filling material in the fracture. When the filling state is an empty crack, no pretreatment is performed.

4. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 3, characterized in that, The grouting parameter decision model in step S3 includes establishing a correspondence between the grouting parameter combination and at least the crack width level and connectivity level in the current crack type, specifically including: When the current fracture type has a width level of wide fracture and a connectivity level of high connectivity, the grouting parameter combination includes: using fast-setting grout mixed with aggregate or cement-water glass grout, matching the grouting pressure to less than 1MPa, matching the grouting rate to no more than 30L / min, and setting the grouting method to intermittent grouting mode. When the current fracture type has a fracture width level of medium fracture and a connectivity level of medium connectivity, the grouting parameter combination includes: using conventional cement-based grout, with the grout concentration varying in a stepwise manner from thin to thick water-cement ratio of 5:1, 3:1, 2:1, 1:1, and 0.5:1, matching the grouting pressure to 1MPa to 3MPa, and matching the grouting rate to 10L / min to 30L / min; When the current fracture type has a width level of micro fracture and a connectivity level of low connectivity, the grouting parameter combination includes: using a stable grout, matching the grouting pressure to be higher than 3MPa, and matching the grouting rate to be lower than 10L / min.

5. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 1, characterized in that, Step S3 is followed by the following steps: S4. Collect real-time response data of the current fracture; wherein, the real-time response data includes grout seepage pressure data, grout seepage data, rock mass micro-strain data and grout temperature within the fracture; Specifically, it includes: By pre-deploying micro-strain sensors in the rock mass surrounding the current crack to be grouted, the micro-strain data of the rock mass reflecting the deformation of the rock mass structure is continuously collected. The grout pressure data, which reflects the fluid pressure of the grout inside the fracture space, is collected by a pressure sensor installed at the grouting hole or extending into the fracture. The slurry seepage data, which reflects the volume of slurry flowing through the flow meter per unit time, is collected by a flow meter installed inside the fissure. The temperature data of the slurry, which reflects the hydration reaction state of the slurry or the ambient temperature, is collected by a temperature sensor that contacts the slurry. The rock mass microstrain data, the grout seepage pressure data within the fracture, the grout seepage data, and the grout temperature data are collected and recorded in a time-synchronized manner to form a multi-dimensional monitoring data sequence with temporal correlation as the real-time response data of the current fracture.

6. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 5, characterized in that, Step S4 is followed by the following steps: S5. Obtain the pre-established grouting parameter correction model, input the real-time response data into the grouting parameter correction model to obtain the real-time working condition type of the current crack; determine whether there is an abnormal working condition type; if so, correct the grouting parameter combination in real time according to the abnormal working condition type to obtain the corrected grouting parameter combination, and then return to step S4 until the grouting construction is completed; wherein, the grouting parameter correction model includes the mapping relationship between real-time response data, abnormal working condition type and grouting parameter combination.

7. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 6, characterized in that, Step S5 involves inputting the real-time response data into the grouting parameter correction model to obtain the real-time working condition type of the current fracture and determine whether there are any abnormal working condition types. Specifically, this includes the following steps: The grouting parameter correction model includes predetermined criteria rules. The real-time response data determines the real-time working condition type of the current fracture through the predetermined criteria rules, and determines whether there are abnormal working condition types. The predetermined criteria rules include the mapping relationship between real-time response data and real-time working condition types. The abnormal working condition types include wide fracture loss working condition, micro-fracture blockage working condition, and rock mass deformation early warning working condition.

8. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 7, characterized in that, The predetermined criterion rules include: When the grout seepage pressure data in the fissure is continuously lower than the first pressure threshold, the grout seepage data is continuously higher than the first flow rate threshold, and the rate of change of the rock mass microstrain data is lower than the first strain rate threshold, it is determined to be the wide fissure loss condition. When the grouting pressure is continuously higher than the second pressure threshold, the grouting rate is continuously lower than the second flow rate threshold, and the rate of change of the grout temperature data is lower than the temperature change rate threshold, it is determined to be the micro-crack blockage condition. When the value of the micro-strain data of the rock mass exceeds the preset strain warning threshold or its rate of change exceeds the preset rate of change warning threshold, it is determined to be a rock mass deformation warning condition.

9. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 8, characterized in that, Step S5 involves real-time correction of the grouting parameter combination based on the abnormal working condition type to obtain the corrected grouting parameter combination, specifically including the following steps: The grouting parameter correction model also includes a preset correction strategy. Based on the abnormal working condition type, the preset correction strategy determines a correction instruction set corresponding to the abnormal working condition type, and executes the correction instruction set to correct the grouting parameter combination in real time, resulting in a corrected grouting parameter combination. The preset correction strategy includes a mapping relationship between the abnormal working condition type and the correction instruction set, and the correction instruction set includes instructions for coordinating the adjustment of one or more parameters among the grout mix ratio, grouting pressure, and grouting rate.

10. The non-uniform grouting method based on multi-dimensional characteristics of tunnel rock mass according to claim 9, characterized in that, The correction instruction set includes: The set of correction instructions corresponding to the wide crack loss condition includes instructions to increase the grout viscosity and / or add a quick-setting agent, instructions to reduce the grouting pressure setting value and / or the grouting rate setting value, and instructions to switch the grouting mode to intermittent grouting mode. The set of correction instructions corresponding to the micro-crack blockage condition includes instructions to reduce grout viscosity and / or add water-reducing agent, as well as instructions to switch the grouting mode to pulse grouting mode; The set of correction instructions corresponding to the rock mass deformation early warning condition includes instructions to reduce the grouting pressure setting value and / or the grouting rate setting value.

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