Grouting method and system for enhancing stability of strip mine slope

Abstract

The invention discloses a grouting method and system for enhancing strip mine slope stability, and belongs to the technical field of slope protection. The grouting method comprises the steps that early-stage data are pre-collected, and an analysis model is established; grouting is designed according to a model analysis result; a pressure-resistant grouting pipe is installed and connected with a grouting pump; grouting parameters are adjusted in real time according to feedback of the sensor; after grouting, all data in the grouting holes are analyzed; outputting a slurry permeation three-dimensional cloud picture, a stress change curve and a stability evaluation index; and storing all monitoring data and model parameters. A cyclic self-adaptive system is formed, it is ensured that the grouting process is efficient and accurate, the overall stability is improved for heterogeneous rock mass, dependence on a static geological report is reduced, and therefore the problem that grouting parameters depend on engineering experience or conservative of the static report is avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of slope protection, and particularly relates to a grouting method and system for enhancing the stability of a slope of an open-pit mine. BACKGROUND

[0002] As a key means for improving the stability of a slope, the grouting reinforcement method has been widely applied in the fields of mines, highways, and water conservancy projects. However, in the prior art, the grouting pressure and the slurry ratio depend on engineering experience or static geological reports. However, the rock mass is heterogeneous, and the use of engineering experience to guide the grouting reinforcement of the rock mass is prone to the problem of conservative design data in a large area of the rock mass. SUMMARY

[0003] In view of the technical problems in the background art, the application provides a grouting method for enhancing the stability of a slope of an open-pit mine, which comprises the following steps: pre-collecting early data and establishing an analysis model; designing grouting according to the model analysis result; installing a pressure-resistant grouting pipe and connecting a grouting pump; adjusting grouting parameters in real time according to sensor feedback; analyzing various data in the grouting hole after grouting; outputting a slurry penetration three-dimensional cloud chart, a stress change curve, and a stability evaluation index; storing all monitoring data and model parameters.

[0004] In some embodiments, in the step of adjusting grouting parameters in real time according to sensor feedback, the step comprises the following steps: solving a seepage equation in real time, updating a permeability coefficient and a slurry diffusion path in combination with sensor feedback, and adjusting grouting pressure and flow.

[0005] In some embodiments, in the step of adjusting grouting parameters in real time according to sensor feedback, the step further comprises the following steps: updating a stiffness matrix according to stress data and displacement data, identifying a potential sliding surface, and optimizing grouting hole positions and depths.

[0006] In some embodiments, in the step of pre-collecting early data and establishing an analysis model, the step comprises the following steps: collecting initial data of the slope, wherein the initial data comprises a rock mass integrity index, a fracture rate, a groundwater level, and geotechnical mechanics parameters.

[0007] In some embodiments, in the step of pre-collecting early data and establishing an analysis model, the step further comprises the following steps: constructing a slope finite element model based on the collected data, and calculating stress concentration zones and potential instability areas.

[0008] In some embodiments, in the step of designing grouting according to the model analysis result, the following steps are included: According to the model analysis result, preset the grouting mode, pressure, flow rate and slurry ratio.

[0009] In some embodiments, after the step of presetting the grouting mode, pressure, flow rate and slurry ratio according to the model analysis result, the step of designing grouting according to the model analysis result further includes: Determine the drilling depth and diameter according to the design.

[0010] In some embodiments, in the step of analyzing the data in the grouting hole after grouting, the following steps are included: Continuously monitor the stress distribution and displacement change after grouting, and verify whether the slurry consolidation range covers the target area.

[0011] In some embodiments, in the step of analyzing the data in the grouting hole after grouting, the following steps are included: Compare the safety factor of the finite element model before and after grouting to confirm the degree of stress concentration relief.

[0012] The application also provides a system for implementing the grouting method for enhancing the stability of the open-pit mine slope, comprising: An information acquisition module acquires rock mass dynamic data through rock mass stress sensors, displacement sensors and slurry diffusion monitoring sensors, wherein the rock mass dynamic data includes rock mass stress, displacement and slurry diffusion range; A data processing module designs preset grouting mode, pressure, flow rate and slurry ratio according to the initial data; predicts the slurry diffusion path and range in combination with the seepage equation according to the real-time updated rock mass parameters; calculates the rock mass stress redistribution and displacement response, and identifies the potential instability area; generates real-time optimization instructions and adjusts the grouting parameters; An execution module adjusts the grouting pressure and flow rate according to the instructions. A central control module is used to control and coordinate the work between the modules.

[0013] The application provides a grouting method for enhancing the stability of an open-pit mine slope, comprising: pre-acquiring early data and establishing an analysis model; designing grouting according to the model analysis result; installing a pressure-resistant grouting pipe and connecting a grouting pump; adjusting the grouting parameters in real time according to sensor feedback; analyzing the data in the grouting hole after grouting; outputting a slurry penetration three-dimensional cloud map, a stress change curve and a stability evaluation index; and storing all monitoring data and model parameters. The working process of the whole method starts from pre-acquiring early data, for example, including drilling sample cores, and establishing an analysis model, thereby laying a scientific foundation; then, a customized grouting scheme is designed based on the model output, and then a pressure-resistant grouting pipe is installed and a grouting pump is connected to perform the operation; in the grouting process, the parameters are adjusted in real time according to the sensor feedback, for example, the grouting pressure or the slurry ratio is adjusted to cope with the rock mass heterogeneity; the data in the hole after grouting are analyzed to verify the effect; then, a three-dimensional penetration cloud map, a stress curve and an evaluation index are output to visualize the reinforcement result; finally, all related data are stored for model updating and future optimization; thus, a cyclic adaptive process is formed, realizing whole-process control from data input to effect verification.

[0014] The technical solution directly reduces the dependence on static geological reports by pre-acquiring early data and establishing an analysis model, thereby avoiding the problem that the grouting parameters depend on engineering experience or the conservatism of static reports; since the rock mass has heterogeneity, the model is dynamically constructed based on real-time collected geological data, rather than fixed parameters, so as to accurately identify local risk points and guide scientific design; then, the grouting is designed according to the model analysis result to ensure parameter customization, avoiding the waste of high-conservatism design of the whole mine; at the same time, in the grouting operation, a pressure-resistant grouting pipe is installed and a grouting pump is connected to provide a robust infrastructure, and the grouting parameters are adjusted in real time according to the sensor feedback, thereby avoiding the deviation caused by experience guidance. In addition, the data in the grouting hole are analyzed after grouting to verify the effect and provide a feedback cycle, and the slurry penetration three-dimensional cloud map, the stress change curve and the stability evaluation index are output to visualize and quantify the reinforcement state, assisting accurate decision-making; storing all monitoring data and model parameters further accumulates knowledge and optimizes the model, continuously reducing the conservative tendency of future dependence on experience, thereby forming a cyclic adaptive system, ensuring that the grouting process is efficient, accurate and targeted to heterogeneous rock mass to improve the overall stability.

[0015] The above description is only a summary of the technical solution of the application, in order to more clearly understand the technical means of the application, which can be implemented according to the content of the specification, and in order to make the above and other purposes, features and advantages of the application more obvious and easy to understand, the specific embodiments of the application are described below. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the present application, the drawings used in the present application will be briefly introduced as follows. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0017] Figure 1 is a basic method step schematic diagram of a grouting method for enhancing the stability of a strip mine slope provided by an embodiment of the present application; Figure 2 is an optimization step schematic diagram of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application, which is about real-time adjustment of grouting parameters; Figure 3 is a further optimization step schematic diagram of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application, which is about real-time adjustment of grouting parameters; Figure 4 is a data collection optimization step schematic diagram of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 5 is a further optimization step schematic diagram of data collection of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 6 is an optimization step schematic diagram of design grouting of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 7 is a further optimization step schematic diagram of design grouting of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 8 is an optimization step schematic diagram of post-grouting data analysis of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 9 is a further optimization step schematic diagram of post-grouting data analysis of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application; Figure 10 is a grouting system structure schematic diagram of the grouting method for enhancing the stability of the strip mine slope provided by an embodiment of the present application.

[0018] Legend of reference signs: 1, information collection module; 2, data processing module; 3, execution module; 4, central control module. DETAILED DESCRIPTION

[0019] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, but cannot limit the protection scope of the present application.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the use of the terms "including," "comprising," "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

[0021] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the technical features indicated. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0022] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification is not necessarily all referring to the same embodiment, or to a particular embodiment, or to a particular set of embodiments. It will be explicitly understood by those of ordinary skill in the art that the embodiments described herein can be combined with other embodiments.

[0023] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0024] In the description of the embodiments of the present application, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0025] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0026] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection; can be direct connection, can also be indirect connection through an intermediate medium, can be internal communication of two elements or interaction relationship of two elements. For those skilled in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0027] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0028] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0029] Reference Figure 1 A grouting method for enhancing the stability of the slope of an open-pit mine, comprising: S101, pre-collecting early data and establishing an analysis model; specifically, the present step carries out field test and monitoring through the particle size distribution, internal stress state and displacement deformation data of the broken rock mass of the slope, obtains the key parameter basis of the designed grouting in combination with theoretical analysis and numerical simulation method, and exemplarily includes the following in the present step: accurately obtaining the particle size distribution characteristics of the broken rock mass, including porosity, fracture connectivity and dominant fracture direction, through drilling core combined with three-dimensional laser scanning technology; exemplarily, the present step also includes: quantifying the grout injectability by testing the porosity variation of the rock mass in real time by using the water injection method or the air pressure method; exemplarily, the present step also includes: monitoring the internal stress variation of the rock mass in real time along the drill hole by arranging the optical fiber sensor; arranging the microseismic probe to capture the rock mass micro-fracture signals caused by the grouting disturbance, and identifying the position of the potential slip surface; arranging the convergence displacement monitoring points on the slope surface and the tunnel hole, obtaining the large-range surface deformation data by satellite remote sensing (InSAR), and analyzing the influence of grouting on the stability of the slope; based on the field test data, constructing the grout splitting and diffusion model to simulate the dominant path and diffusion radius of the grout in the broken rock mass; using the fluid-structure coupling numerical simulation (such as the simulation calculation software FLAC3D and the multi-physical simulation software COMSOL developed by the ITASCA company of the United States), inverting the correlation between the grouting pressure and the rock mass displacement, and optimizing the pressure threshold to avoid excessive disturbance; simulating the reinforcement effect under different layer heights, grouting times and pressure combinations, including the strength growth rate and the permeability coefficient reduction rate, and identifying the main control factors by orthogonal test design.

[0030] S102, design grouting according to model analysis results; specifically, determine grouting key parameters including layer height, grouting times, pressure range using parameter data obtained in S101, illustratively, according to vertical zoning of fracture development, combine drilling core rock quality index value and fracture distribution, divide rock layers with similar degrees of crushing into the same grouting section to obtain layer height design value; first-order hole fills large fractures by low-pressure permeation, second-order hole fills micro-fractures by high-pressure splitting, determine the number of sequences through the characteristics of gradually increasing super-pore water pressure excitation; based on real-time pressure-flow curve, pause grouting when pressure drops suddenly or flow increases suddenly, re-inject after slurry initial setting to avoid slurry loss and realize dynamic adjustment of the grouting process; the lower limit value of grouting pressure range is calculated according to hydrostatic pressure and rock mass splitting resistance, and the upper limit value is determined by in-situ shear test and numerical simulation to determine the critical pressure that does not induce harmful displacement.

[0031] S103, install pressure-resistant grouting pipe and connect grouting pump; S104, adjust grouting parameters in real time according to sensor feedback; specifically, rely on stress sensor and displacement meter data embedded in the drilling hole, when local rock mass displacement is abnormally increased, dynamically reduce the grouting pressure below the critical splitting pressure to avoid excessive expansion of hydraulic splitting and cause rock mass structure damage; when the slurry diffusion speed is lower than the model prediction value, increase the pressure to overcome the permeability resistance of the rock layer, this process realizes the dynamic matching of slurry diffusion range and rock mass strength through real-time control, the core purpose is to avoid reinforcement failure caused by insufficient or excessive splitting.

[0032] S105, analyze various data in the grouting hole after grouting; specifically, including extracting the stone rate of grouting body, the distribution form of slurry vein and the side friction resistance improvement value of anchoring section, illustratively, detect the filling rate of slurry to fracture through drilling core detection, and compare the compressive strength increment of rock core before and after grouting, to verify the mechanism of splitting grouting through slurry vein extrusion of rock-soil mass, improve friction angle and embedded effect, evaluate reinforcement performance and obtain empirical data.

[0033] S106, output slurry permeation three-dimensional cloud map, stress change curve and stability evaluation index; specifically, the three-dimensional cloud map reconstructs the diffusion path of slurry in rock mass according to grouting pressure, flow time series data, reveals the preferential permeation characteristics of slurry in bedding slope area, these output quantities quantify the improvement effect of grouting on slope stability, avoiding the problem that traditional methods cannot visualize the reinforcement quality.

[0034] S107, store all monitoring data and model parameters. Specifically, store all monitoring data and model parameters to form a historical database for iterative optimization of subsequent grouting design. For example, by comparing the grouting response data of different lithology (such as quartz sandstone and limestone), the calculation formula of slurry viscosity coefficient and diffusion radius in the model can be corrected, and the continuous improvement of parameter design can be realized.

[0035] The technical solution directly reduces the dependence on static geological reports by pre-acquiring early data and establishing an analysis model, thereby avoiding the conservative problem of grouting parameters depending on engineering experience or static reports; since the rock mass is heterogeneous, the model is dynamically constructed based on real-time collected geological data, rather than fixed parameters, so it can accurately identify local risk points and guide scientific design; then, according to the model analysis result, the grouting is designed to ensure parameter customization, avoiding the waste of high conservative design in the whole mine; at the same time, in the grouting operation, the pressure-resistant grouting pipe is installed and connected to the grouting pump to provide a robust infrastructure, and real-time adjustment of grouting parameters according to sensor feedback helps real-time monitoring of heterogeneous changes and dynamic optimization of parameters, thereby avoiding the deviation caused by experience design. In addition, the effect of each data in the grouting hole is analyzed after grouting to provide a feedback cycle, and the output of slurry penetration three-dimensional cloud map, stress change curve and stability evaluation index can visualize and quantify the reinforcement state, which assists accurate decision-making; storing all monitoring data and model parameters further accumulates knowledge and optimizes the model, continuously reduces the conservative tendency of relying on experience in the future, thereby forming a circulating adaptive system to ensure efficient and accurate grouting process and improve the overall stability of the heterogeneous rock mass.

[0036] In some embodiments, reference is made to Figure 2 In S104, real-time adjustment of grouting parameters according to sensor feedback, including: S1041, real-time solution of seepage equation, combination of sensor feedback to update permeability coefficient and slurry diffusion path, adjustment of grouting pressure and flow. Specifically, based on the pre-acquired slope geological data, including rock mass fracture distribution, initial value of permeability coefficient, porosity, a seepage model of slurry diffusion is established to describe the diffusion behavior of slurry in rock and soil pores and fractures, for example, the seepage model of slurry diffusion is: Wherein: p: slurry pressure distribution; it drives the movement of slurry in the fracture network, which is obtained synchronously by the orifice pressure sensor and the in-hole distributed optical fiber.

[0037] k: rock mass permeability coefficient; it reflects the fracture development degree (such as fracture density and opening), which is controlled by geological structure. It is obtained by field test and geological analysis, for example, the permeability coefficient is obtained by converting the rock permeability quantified by the Lvrong test.

[0038] t: time; : Gradient operator; in discrete model, it represents the pressure difference between adjacent nodes in space grid.

[0039] : The divergence of slurry flux, i.e. the net flow of slurry per unit time through a unit volume of rock mass; : The rate of change of pressure with time, reflecting the dynamic balance process of slurry diffusion.

[0040] The term represents the spatial gradient of pressure, indicating the movement trend of slurry from high pressure area to low pressure area, and through this term, the flow path of slurry in the hole can be determined; the term k is a tensor due to the directionality of rock mass cracks, i.e. k is a three-dimensional matrix, and through eigenvalue decomposition, the permeation eigenvalues in three directions can be obtained, when one of them is much higher than the other two, it can be shown that there is a dominant seepage direction in the rock mass in this direction, thereby determining the main direction of slurry permeation in the hole, and then the subsequent grouting hole arrangement can be optimized according to the characteristics of the rock mass, and the effective diffusion range of the slurry is improved; the diffusion rate is determined by , and the influencing term is the pressure distribution p and the rock mass permeability coefficient k, and combined with the porosity in the rock mass and the grouting time, the slurry diffusion radius can be derived, and thus combined with the flow path and the main direction of permeation, the slurry diffusion model is obtained, thereby guiding the parameter design of grouting amount and pressure, and reducing the risk of over-grouting or under-grouting.

[0041] When , it indicates that the slurry is blocked or bypassed, and the grouting pressure needs to be increased or low viscosity slurry needs to be used, thereby avoiding the grouting blind area and ensuring the uniformity of reinforcement; When , it indicates that the slurry is blocked or bypassed, and the grouting pressure needs to be increased or low viscosity slurry needs to be used, thereby avoiding the grouting blind area and ensuring the uniformity of reinforcement; , the attenuation speed is faster than the designed value, indicating that the slurry is gelled too early, and a retarder needs to be added or the grouting flow needs to be increased to avoid pipeline blockage and interruption of grouting, thereby realizing real-time adjustment of grouting work.

[0042] In some embodiments, with reference to Figure 3 , in S104, real-time adjustment of grouting parameters according to sensor feedback, further includes: S1042, updating the stiffness matrix according to the stress data and the displacement data, identifying the potential sliding surface, and optimizing the grouting hole position and depth. Specifically, the method dynamically corrects the stiffness matrix of the rock-soil mass, i.e., a mathematical model describing the deformation response of the rock-soil mass under stress conditions, by real-time monitoring of the stress distribution and displacement changes inside the slope. This updating process is based on the real-time data fed back by the sensors in S101, combined with geomechanical parameters (such as elastic modulus, Poisson's ratio) to recalculate the local stiffness characteristics of the slope, thereby more accurately simulating the actual deformation behavior of the rock-soil mass.

[0043] After updating the stiffness matrix, the system locates the risk area of slope instability by identifying the potential sliding surface. The principle is that when the stiffness of the rock-soil mass decreases significantly (such as due to crack propagation or rock layer softening), the displacement data will show non-continuous jumps, while the stress data will show local stress relaxation or concentration phenomena; by comparing the differences between the updated stiffness matrix and the initial model, combined with limit equilibrium analysis or numerical simulation (such as FLAC3D), the potential location and orientation of the sliding surface can be identified. For example, if the displacement data indicates that there is a continuous shear displacement in a certain area, and the stress data reflects that the shear strength of that area has decreased, it is determined that this is a development area of the sliding surface.

[0044] Based on the analysis of the system, the grouting hole position and depth are further optimized. Specifically, the grouting hole position avoids the stable rock mass area and is preferentially arranged in the vertical direction of the potential sliding surface extension path to ensure that the grout can effectively penetrate the sliding surface; at the same time, the grouting depth is dynamically adjusted according to the buried depth of the sliding surface. For example, if the sliding surface is located in the shallow layer, short-hole intensive grouting is used; if the sliding surface penetrates into the slope, deep-hole directional grouting is designed to make the grout vein extend to the bottom of the sliding surface to form an anti-slide anchoring area. This optimization improves the pertinence of grouting and avoids the waste of grout or the formation of reinforcement blind area caused by blind hole arrangement.

[0045] This step mainly solves the problem of local instability of the open-pit slope caused by the development of rock mass structural plane. The stiffness matrix update quantifies the degradation of the deformation characteristics of the rock-soil mass, providing a mechanical basis for sliding surface identification; the sliding surface positioning locks the reinforcement target area; finally, through the optimization of the grouting hole position and depth, the grout fills the cracks around the sliding surface under high pressure, and the shear resistance of the grout vein and stone body inhibits the expansion of the sliding surface, thereby avoiding the waste of grout or the formation of reinforcement blind area caused by blind hole arrangement.

[0046] In some embodiments, reference is made to Figure 4, S101, the pre-acquisition of early data and the establishment of an analysis model, comprising: S1011, collecting initial data of the slope, including rock mass integrity index, fracture rate, groundwater level and geotechnical mechanics parameters. Specifically, the rock mass integrity index is obtained by calculating the drilling core sampling rate and the rock quality index. For example, the length of the intact core segment is used to quantify the damage degree of the rock mass structure after geological drilling sampling; the fracture rate is measured by surface mapping and drilling camera technology to measure the fracture area ratio in unit volume of rock mass, reflecting the development state of rock mass permeation channel; the groundwater level is obtained by burying water level monitoring well to obtain dynamic data, which is used to analyze the influence of water pressure on rock mass effective stress; the geotechnical mechanics parameters include the mechanical property parameters of the rock mass itself, for example, including shear strength, elastic modulus and Poisson's ratio, which are determined by in-situ direct shear test, triaxial test or geological radar inversion, and are used to describe the deformation and failure characteristics of rock-soil body under grouting pressure. Among them, the rock mass integrity index and the fracture rate jointly define the spatial distribution of the rock mass structure surface network, and the crack propagation path is simulated by the discrete crack network system, so as to predict the preferential diffusion direction of the slurry under high pressure; the groundwater level data is input into the seepage and stress coupling model, which can quantify the weakening effect of groundwater on rock mass effective stress, and accordingly delimit the dynamic water disturbance area which needs to be avoided for grouting, thereby guiding the arrangement mode of the grouting hole; the geotechnical mechanics parameters drive the construction of the stiffness matrix and the limit equilibrium equation, for example, the potential slip risk of the interface between different rock masses is calculated by the Mohr-Coulomb criterion to provide mechanical boundary conditions for grouting design.

[0047] In some embodiments, with reference to Figure 5 , S101, the pre-acquisition of early data and the establishment of an analysis model, further comprising: S1012, based on the collected data to construct a slope finite element model, calculate the stress concentration area and the potential instability area. Specifically, based on the collected rock mass integrity index, fracture rate, groundwater level and rock and soil mechanics parameters, these data are taken as input conditions, and a three-dimensional geomechanical model of the slope is constructed through a finite element analysis software (such as nonlinear finite element method software ABAQUS or FLAC3D). Among them, the rock mass integrity index and the fracture rate define the rock mass structure surface network together, the fracture expansion path is simulated through the discrete fracture network (DFN) system, and the slurry diffusion direction is predicted; the groundwater level data is input into the seepage-stress coupling model to quantify the weakening effect of pore water pressure on rock mass effective stress; the rock and soil mechanics parameters drive the stiffness matrix and the Mohr-Coulomb criterion calculation to determine the slip risk of the interface between different rock types. After the model is constructed, the stress concentration and the potential instability area are calculated to locate the grouting reinforcement target. The finite element model discretizes the slope rock mass through mesh, applies the self-weight load, tectonic stress and groundwater seepage field boundary conditions, and solves the node displacement and element stress distribution; when the maximum principal stress of a certain area exceeds the compressive strength of the rock mass or the minimum principal stress is lower than the tensile strength, it is determined as a stress concentration area; at the same time, through the shear strain increment mutation or the plastic zone penetration analysis, the potential instability area is identified, thereby providing a parameter basis for the design of the overall grouting work.

[0048] In some embodiments, with reference to Figure 6 , S102, designing grouting in the model analysis result, including: S1021, according to the model analysis result, presetting the grouting mode, pressure, flow and slurry ratio. Specifically, based on the rock fracture distribution and groundwater level data obtained in S101, the grouting mode is adaptively selected. For example, when the model analysis shows that there are dense fracture zones in the shallow layer of the slope, a segmented grouting mode is adopted, low-viscosity slurry is injected in the shallow layer to fill micro cracks, and high-strength slurry is injected in the middle and deep layers to strengthen the rock skeleton, thereby achieving differential reinforcement in layers, matching the crack spatial distribution characteristics, avoiding excessive diffusion of slurry in the fracture development area, and reducing invalid perfusion.

[0049] The preset grouting pressure is dynamically set according to the rock and soil mechanics parameters obtained in S101, and the pressure threshold of each grouting segment is set. For example, in low-permeability rock layers, the upper limit of the pressure is set to a relatively high value to ensure the effective diffusion of the slurry, and in high-permeability fault zones, the pressure is reduced to a relatively low value to avoid slurry loss. The core function of this parameter is to balance the rock mass splitting risk and the slurry diffusion efficiency, and to control the capillary permeation rate of the slurry in the cracks through pressure, so that the slurry forms a continuous filling network in the pores. If the pressure is too low, the slurry will not be able to penetrate the micro cracks, and if the pressure is too high, new cracks may be induced.

[0050] The preset grouting flow rate needs to be combined with the model-predicted pore connectivity to control the flow rate of a single hole. For example, when the sensor feedback indicates that the fracture connectivity rate of a certain area is high, the flow rate is reduced to avoid the loss of slurry through a short path; and in the area with low connectivity rate, the flow rate is increased to accelerate the saturation filling. In this case, the higher and lower are relative to the design value in the project. This parameter adjusts the volume of slurry injected per unit time to synchronize with the absorption rate of the rock mass, thereby maintaining the continuity of grouting and avoiding local cavities.

[0051] The preset slurry ratio is based on the underground water level and rock-soil composition data collected in S101. For example, when the underground water level is higher than the grouting area, a rapid-setting cement slurry with a water-cement ratio of 0.6:1 is used to resist water erosion; if the rock mass contains clay minerals, 1%-2% of dispersant is added to improve the permeability of the slurry.

[0052] The parameters in this step correspond one by one to the model parameters provided in S101, and the data obtained by the sensor in S101 are directly converted into the basis for selecting the grouting mode and the reference for the slurry ratio, ensuring that the parameter presetting accurately corresponds to the geological conditions and providing a scientific basis for grouting design; the preset parameters serve as the reference values for real-time adjustment, and combined with the feedback of the sensor, dynamic control can be formed to avoid the problem that static parameters cannot adapt to the changes in the dynamic mechanical properties of the heterogeneous rock mass.

[0053] In some embodiments, reference is made to Figure 7 After S1021, the grouting mode, pressure, flow rate, and slurry ratio are preset according to the model analysis results, S102, the design of grouting according to the model analysis results further includes: S1022, determining the drilling depth and diameter according to the design. Specifically, this step is a fine design step based on the grouting design parameters provided in S1021 and the model analysis results in S101, and the core purpose is to optimize the drilling geometry parameters to ensure that the slurry accurately covers the target rock layer, and to solve the problems of uneven slurry penetration, blind reinforcement area, and resource waste caused by the mismatch between drilling parameters and geological conditions in traditional grouting. The drilling depth is dynamically set according to the depth of the potential unstable area in the model analysis and the rock-soil mechanical parameters. For example, when the model shows that there is a fracture-dense zone or a soft interlayer in the deep part of the slope, the drilling depth needs to penetrate the unstable layer and reach the stable rock layer to ensure that the anchoring segment is located in the intact rock mass. If the depth is insufficient, the grouting body cannot form a continuous anchoring structure, which is prone to cause shallow collapse; and if the depth is too large, it will cause resource waste. Therefore, by matching the spatial distribution of the unstable area, the slurry can be fully filled along the vertical fractures under the driving of pressure to enhance the shear strength of the rock mass, while avoiding the problem of waste of construction resources caused by blind setting of grouting holes.

[0054] The borehole diameter is designed based on the grouting pressure and slurry ratio preset in S1021. For example, for high-viscosity slurries (e.g., a water-cement ratio of 0.4:1) or high-pressure grouting (e.g., grouting pressure greater than 1 MPa, depending on geological conditions), a larger borehole diameter (e.g., 110-130 mm) is used to reduce slurry flow resistance and accommodate more grouting pipes. For low-viscosity slurries (e.g., a water-cement ratio of 0.8:1) or low-pressure grouting (e.g., grouting pressure less than or equal to 0.5 MPa, which is considered low pressure grouting compared to the 1 MPa grouting provided in this example), the borehole diameter can be reduced to 75-90 mm to control the slurry diffusion radius. A grouting hole diameter that is too small will limit slurry diffusion efficiency, while a large diameter can easily cause slurry upwelling and loss. This step optimizes the radial penetration rate and range of the slurry in the rock formation through parameter-guided borehole diameter adjustment, ensuring a uniform distribution of the slurry vein network.

[0055] In some embodiments, reference Figure 8 , in S105, after grouting, the data in the grouting hole are analyzed, including: S1051. After grouting, continuously monitor stress distribution and displacement changes to verify whether the slurry consolidation range covers the target area. The core purpose of this step is to ensure that the grouting effect matches the design expectations through real-time data feedback, thereby avoiding the problem of difficult to quantify and evaluate the reinforcement effect due to the uncontrollable slurry diffusion in traditional grouting technology, which in turn leads to the existence of reinforcement blind spots or weak areas. Specifically, continuous monitoring of stress distribution is achieved by deploying a network of micro stress sensors around the grouting holes. These sensors capture the stress redistribution state within the rock and soil during the slurry consolidation process in real time. The stress change of the rock and soil directly reflects the compaction effect of the slurry after filling the cracks. When the slurry fills the cracks and solidifies, its volume expansion squeezes the surrounding rock and soil particles, forming a dense structure from the originally loose rock and soil skeleton, thereby increasing the internal friction angle and cohesion of the rock and soil. If the stress concentration area is not detected in the target area, it means that the slurry has not effectively covered the area, and the supplementary grouting process needs to be triggered.

[0056] Simultaneously, displacement changes are monitored using high-precision inclinometers and surface displacement meters, focusing on the displacement rate and direction at key slope points. Displacement data can reveal the effect of slurry consolidation on the overall slope stiffness. The resulting meshwork of stone and rock interlocks with the soil, inhibiting shear slip along the structural surface and thus reducing displacement deformation. If displacement continues to increase or shows an abnormal direction, it indicates that the anti-slip strength of the target area has not been significantly enhanced, and verification is required to determine whether the slurry diffusion has deviated from the pre-set path.

[0057] Whether the slurry solidification range covers the target area depends on the comprehensive analysis of the data measured in this step. The specific principle is: input the stress and displacement data into the finite element model, inverse the actual diffusion path and solidification form of the slurry, generate a three-dimensional cloud chart of slurry penetration, and through superposition and comparison with the geological model in the design stage, it is directly displayed whether the slurry completely fills the target fracture network (such as the bedding surface of the forward slope or the intersection area of the wedge-shaped slide). If it is not covered, it is necessary to verify the local rock-soil strength improvement effect by drilling core and optimize the subsequent grouting parameters, so as to verify the coincidence degree of the slurry solidification range and the target area through quantification, improve the verification accuracy of the grouting process, and enhance the slope stability.

[0058] In some embodiments, with reference to Figure 9 In S105, the analysis of various data in the grouting hole after grouting also includes: S1052, compare the safety factors of the finite element models before and after grouting to confirm the stress concentration relief degree. Specifically, the safety factor calculation of the finite element model before and after grouting depends on the limit equilibrium method or numerical analysis method. The model is updated by inputting the rock-soil parameters after grouting. The internal friction angle and cohesion of the rock-soil after grouting are improved due to the filling of the slurry in the cracks, and the shear strength parameters are optimized to enhance the sliding resistance of the sliding surface in the model. The expression of the safety factor (Fs) is Fs = sliding resistance / sliding force. The increase of the sliding resistance after grouting directly reflects the improvement of the Fs value. If the Fs value after grouting does not reach the design threshold (usually ≥1.3), it indicates that the mechanical reinforcement of the target area is insufficient.

[0059] The embodiment also discloses a system for implementing the grouting method for enhancing the slope stability of the open-pit mine disclosed in the application, with reference to Figure 10 , comprising: An information acquisition module 1 acquires rock mass dynamic data including rock mass stress, displacement and slurry diffusion range through rock mass stress sensors, displacement sensors and slurry diffusion monitoring sensors; A data processing module 2 designs a preset grouting mode, pressure, flow and slurry ratio according to the initial data; predicts the slurry diffusion path and range according to the real-time updated rock mass parameters combined with the seepage equation; calculates the rock mass stress redistribution and displacement response, and identifies the potential instability area; generates real-time optimization instructions and adjusts the grouting parameters; An execution module 3 adjusts the grouting pressure and flow according to the instructions; A central control module 4 is used to control and coordinate the work between the modules.

[0060] The above merely describes specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any modification, equivalent replacement, and improvement within the technical range disclosed by the present application and within the spirit and principle of the present application should be encompassed within the protection scope of the present application.

[0061] Note that the present application is not limited to the above-described embodiments. The above-described embodiments are merely examples, and embodiments having substantially the same configuration and exerting the same effects as the technical idea within the technical scope of the present application are also included in the technical scope of the present application. Furthermore, other modes constructed by applying various modifications to the embodiments or combining part of the configuration elements of the embodiments that a person skilled in the art can conceive within the scope of the gist of the present application are also included in the scope of the present application.

Claims

1. A grouting method for enhancing the stability of open pit mine slopes, characterized in that: include: Pre-collect preliminary data and establish analysis models; Design grouting based on model analysis results; Install the pressure-resistant grouting pipe and connect the grouting pump; Adjust grouting parameters in real time based on sensor feedback; After grouting, analyze the data in the grouting hole; Output slurry penetration three-dimensional cloud map, stress change curve and stability evaluation index; Store all monitoring data and model parameters.

2. A grouting method for enhancing the stability of open pit mine slopes according to claim 1, characterized in that: The real-time adjustment of grouting parameters according to sensor feedback includes: Solve the seepage equation in real time, update the permeability coefficient and slurry diffusion path based on sensor feedback, and adjust the grouting pressure and flow rate.

3. A grouting method for enhancing the stability of open pit mine slopes according to claim 2, characterized in that: The method of adjusting the grouting parameters in real time according to sensor feedback further includes: Update the stiffness matrix based on stress and displacement data, identify potential slip surfaces, and optimize grouting hole locations and depths.

4. A grouting method for enhancing the stability of open pit mine slopes according to claim 1, characterized in that: The pre-collection of preliminary data and establishment of an analysis model include: Initial slope data are collected, including rock mass integrity index, crack ratio, groundwater level and geotechnical parameters.

5. A grouting method for enhancing the stability of open pit mine slopes according to claim 4, characterized in that: The pre-collection of preliminary data and establishment of an analysis model also includes: Based on the collected data, a finite element model of the slope is constructed to calculate stress concentration areas and potential unstable areas.

6. A grouting method for enhancing the stability of open pit mine slopes according to claim 1, characterized in that: The grouting design according to the model analysis results includes: Based on the model analysis results, the grouting mode, pressure, flow rate and slurry ratio are preset.

7. A grouting method for enhancing the stability of open pit mine slopes according to claim 6, characterized in that: After the grouting mode, pressure, flow rate and slurry ratio are preset according to the model analysis results, the grouting design according to the model analysis results further includes: Determine the drilling depth and diameter according to the design.

8. A grouting method for enhancing the stability of open pit mine slopes according to claim 1, characterized in that: The analysis of various data in the grouting hole after grouting includes: After grouting, the stress distribution and displacement changes are continuously monitored to verify whether the slurry consolidation range covers the target area.

9. A grouting method for enhancing the stability of open pit mine slopes according to claim 8, characterized in that: The analysis of the data in the grouting hole after the grouting also includes: Compare the safety factors of the finite element model before and after grouting to confirm the degree of stress concentration relief.

10. A system for implementing the grouting method for enhancing the stability of an open-pit mine slope as claimed in any one of claims 1 to 9, comprising: An information acquisition module (1) acquires rock mass dynamic data through a rock mass stress sensor, a displacement sensor, and a slurry diffusion monitoring sensor, wherein the rock mass dynamic data includes rock mass stress, displacement, and slurry diffusion range; The data processing module (2) designs the preset grouting mode, pressure, flow rate and slurry ratio according to the initial data; predicts the slurry diffusion path and range based on the real-time updated rock mass parameters and the seepage equation; calculates the rock mass stress redistribution and displacement response, identifies the potential unstable area; generates real-time optimization instructions and adjusts the grouting parameters; Execution module (3), adjusting grouting pressure and flow according to instructions; The central control module (4) is used to control and coordinate the work between the modules.

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