Tunnel surrounding rock grouting reinforcement process simulation analysis method and system

Abstract

The application provides a tunnel surrounding rock grouting reinforcement process simulation analysis method and system, relates to the tunnel surrounding rock reinforcement simulation technical field, and effectively improves the spatial resolution of the surrounding rock deformation state monitoring through the arrangement of multiple evaluation interfaces in the tunnel axis direction and the multi-point synchronous strain collection; the volume strain hardening index normalization analysis can dynamically and quantitatively reflect the mechanical property evolution of the surrounding rock after being compressed; the volume strain of the surrounding rock is dynamically coupled with the rheological test parameters of the grouting material, the timeliness and accuracy of the slurry permeability and pressure correction are improved; the linear interpolation method is used to realize the continuous distribution calculation of the grouting pressure in the tunnel axial direction, and the simulation analysis is significantly improved in the refinement and practicability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel surrounding rock reinforcement simulation, in particular to a tunnel surrounding rock grouting reinforcement process simulation analysis method and system. BACKGROUND

[0002] Tunnel surrounding rock grouting reinforcement, as a key technology in the construction of underground projects such as subways, highways, and railways, is widely used in scenarios such as improving the overall stability of surrounding rock, preventing and controlling water disasters, and improving structural durability. With the expansion of tunnel excavation scale and the increasing complexity of geological conditions, the simulation analysis of the grouting reinforcement process is required not only to reflect the mechanical property changes of surrounding rock during grouting, but also to adapt to the dynamic evolution of surrounding rock state, and to realize real-time evaluation and dynamic optimization of grouting effect.

[0003] Currently, existing technologies mostly use limited monitoring points arranged at local positions of the tunnel to collect single strain data in the axial or ring direction, and estimate the surrounding rock deformation and grouting pressure by combining empirical formulas or static parameters. This kind of method often ignores the synchronous dynamic response of the full-face, multi-point, and multi-parameter of surrounding rock, making it difficult to timely and accurately reflect the compression characteristics and mechanical property changes of surrounding rock during the grouting process. At the same time, the existing scheme mostly sets the rheological parameters of grouting materials as static or based on laboratory conditions, which fails to dynamically couple with the compressed deformation state of the surrounding rock on site, resulting in insufficient accuracy of the estimation of grouting pressure and grouting material permeability. In addition, the existing technology is mainly limited to discrete measuring points for the calculation of grouting pressure distribution, making it difficult to realize continuous interpolation estimation of pressure at any position along the axial direction of the tunnel, which affects the optimization of grouting control parameters and the identification of safety risks.

[0004] Therefore, how to construct a volume strain hardening index that can accurately reflect the compression characteristics of surrounding rock based on multi-interface and multi-point synchronous strain signal collection, and dynamically couple with the rheological parameters of grouting materials, and then realize the continuous distribution simulation of grouting pressure along the full axial direction of the tunnel, is a technical problem to be solved in the field of simulation analysis of tunnel surrounding rock grouting reinforcement process.

[0005] The above information disclosed in the background section is only used to strengthen the understanding of the background of the present disclosure, and therefore it can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0006] The purpose of the present application is to provide a tunnel surrounding rock grouting reinforcement process simulation analysis method and system to solve the problems raised in the background.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] In a first aspect, the present application provides a tunnel surrounding rock grouting reinforcement process simulation analysis method, comprising the following specific steps:

[0009] S1: multiple evaluation interfaces are arranged along the axial direction of the surrounding rock of the tunnel to be processed according to a preset interval, and a monitoring point is selected in each evaluation interface, and a strain signal including an axial strain and a hoop strain is synchronously collected for each monitoring point;

[0010] S2: based on the strain signal of each evaluation interface, a volume strain of the corresponding evaluation interface is constructed by using a linear weighting method, the volume strain is used to represent the compression characteristics of the surrounding rock of the evaluation interface, and a volume strain hardening index is further constructed based on the volume strain, the volume strain hardening index is used to reflect the change of the mechanical properties of the surrounding rock after compression, and the static viscosity of the grouting material is determined in combination with the rheological test parameters;

[0011] S3: based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, a grouting dynamic viscosity coefficient corresponding to the evaluation interface is obtained by using a strain hardening dynamic coupling method, the grouting dynamic viscosity coefficient is used to describe the rheological characteristics of the slurry in the reinforcement process with the deformation evolution of the surrounding rock;

[0012] S4: according to the obtained dynamic viscosity coefficient, the slurry permeability of the evaluation interface is evaluated by using an exponential decay permeability model, and a grouting pressure correction factor of the evaluation interface is calculated in real time, and the pressure correction factor is used as a correction term of the grouting pressure of the evaluation interface;

[0013] S5: based on the grouting pressure correction factor of each evaluation interface, the grouting pressure value of each evaluation interface is dynamically constructed in combination with a theoretical reference pressure value, and the grouting pressure of any interface in the axial direction of the tunnel is determined by using a linear interpolation method, so that the simulation analysis of the grouting reinforcement process of the surrounding rock of the tunnel is realized.

[0014] Further, the strain signal including the axial strain and the hoop strain is synchronously collected for each monitoring point, and the specific process is as follows:

[0015] The monitoring points are arranged at equal intervals along the axial direction of the surrounding rock, the axial strain at the monitoring points is measured, and the measured value is taken as the axial strain of the evaluation interface;

[0016] The monitoring points are arranged at equal intervals along the hoop direction at the crown and haunch position regions of the symmetric axis of each evaluation interface, the hoop strain value is measured, and the average value of the hoop strain values of all hoop positions is taken as the hoop strain of the evaluation interface.

[0017] Further, the strain signal of each evaluation interface is constructed by using linear weighting, and the specific process is as follows:

[0018] Based on the strain signal of each evaluation interface, the volume strain of each evaluation interface is constructed by using linear weighting:

[0019] ;

[0020] denotes the axial strain of the first evaluation interface; denotes the hoop strain of the first evaluation interface, denotes the volume strain of the first evaluation interface; and respectively denote the axial strain, the hoop strain weight, and both are greater than 0, .

[0021] Further, when the volume strain hardening index is constructed based on the volume strain, according to the uniaxial compressive strength and the elastic modulus of the surrounding rock, the ratio of the uniaxial compressive strength and the elastic modulus is calculated as the critical volume strain of each evaluation interface, and the volume strain of each evaluation interface is divided by the critical volume strain to obtain the volume strain hardening index.

[0022] Further, based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, a strain hardening dynamic coupling method is adopted to obtain the grouting dynamic viscosity coefficient corresponding to the evaluation interface, and the formula is:

[0023] ;

[0024] wherein, denotes the dynamic viscosity coefficient based on the volume strain of the first evaluation interface; denotes the static viscosity coefficient of the surrounding rock; denotes the hardening sensitive coefficient; denotes the power index, denotes the volume strain hardening index of the first evaluation interface.

[0025] Further, when the grouting pressure value of each evaluation interface is dynamically constructed, based on the dynamic viscosity coefficient, an exponential decay permeability model is adopted to evaluate the grouting permeability of the evaluation interface, and then the real-time calculation of the grouting pressure correction factor of the evaluation interface is carried out, and the formula is:

[0026] ;

[0027] wherein,

[0028] ;

[0029] wherein, denotes the static reference viscosity coefficient, denotes the reference permeability, ​​​​​a permeability of the i th evaluation interface, a pressure correction factor of the i th evaluation interface, a permeability decay coefficient of the i th evaluation interface,

[0030] a grouting pressure value of the i th evaluation interface,

[0031]

[0032] a grouting pressure value of the i th evaluation interface, a theoretical reference pressure value of the i th evaluation interface.

[0033] Further, the specific steps for determining the grouting pressure of any interface in the axial direction of the tunnel are as follows:

[0034] The preset interval of adjacent evaluation interfaces is , and the axial interval between adjacent evaluation interfaces is , wherein represents the maximum axial interval value of the i th evaluation interface, represents the minimum axial interval value of the i th evaluation interface, and for any point in the interval, the grouting pressure value is linearly interpolated according to the axial relative distance:

[0035]

[0036] represents the pressure value when the axial distance is .

[0037] In a second aspect, the present application provides a tunnel surrounding rock grouting reinforcement process simulation analysis system, which is used to execute the above-mentioned analysis method, and comprises:

[0038] a data acquisition module, configured to set a plurality of evaluation interfaces according to a preset interval along the axial direction of the tunnel surrounding rock to be processed, select a monitoring point in each evaluation interface, and synchronously acquire strain signals including axial strain and hoop strain for each monitoring point;

[0039] ​​​​​​​​The hardening index construction module is used for constructing the volume strain of the corresponding evaluation interface by adopting a linear weighting method based on the strain signal of each evaluation interface, using the volume strain for representing the compression characteristics of the surrounding rock of the evaluation interface, further constructing a volume strain hardening index based on the volume strain, and the volume strain hardening index is used for reflecting the mechanical property change of the surrounding rock after compression, and the static viscosity of the grouting material is determined in combination with the rheological test parameters;

[0040] The viscosity coefficient construction module is used for obtaining the grouting dynamic viscosity coefficient of the evaluation interface by adopting a strain hardening dynamic coupling mode based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, and the grouting dynamic viscosity coefficient is used for describing the rheological characteristics of the slurry in the reinforcement process along with the deformation evolution of the surrounding rock;

[0041] The correction factor construction module is used for evaluating the slurry permeability of the evaluation interface by adopting an exponential decay permeability model according to the obtained dynamic viscosity coefficient, and then performing real-time calculation on the grouting pressure correction factor of the evaluation interface, and the pressure correction factor is used as a correction term of the grouting pressure of the evaluation interface;

[0042] The interpolation simulation module is used for dynamically constructing the grouting pressure value of each evaluation interface based on the grouting pressure correction factor of each evaluation interface in combination with the theoretical benchmark pressure value, and the grouting pressure of the arbitrary interface in the tunnel axial direction is determined by adopting a linear interpolation method, so that the simulation analysis on the grouting reinforcement process of the surrounding rock of the tunnel is realized.

[0043] Compared with the prior art, the beneficial effects of the present application are:

[0044] The present application effectively improves the spatial resolution of the deformation state monitoring of the surrounding rock by arranging multiple evaluation interfaces in the axial direction of the tunnel and performing multi-point synchronous strain collection; the volume strain hardening index normalization analysis can dynamically and quantitatively reflect the mechanical property evolution of the surrounding rock after compression; the dynamic coupling of the volume strain of the surrounding rock and the rheological test parameters of the grouting material improves the timeliness and accuracy of the slurry permeability and pressure correction; the linear interpolation method is used to realize the continuous distribution calculation of the grouting pressure in the axial direction of the tunnel, and the refinement and practicability of the simulation analysis are significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 It is a whole method flowchart of the present application;

[0046] Figure 2 It is a strain representation diagram of the monitoring point area in the evaluation interface;

[0047] Figure 3 It is a volume hardening index-dynamic viscosity coefficient fitting curve diagram;

[0048] Figure 4A volume hardening index-dynamic viscosity coefficient columnar statistical chart;

[0049] Figure 5 A schematic diagram of the overall structure of the system of the present application. DETAILED DESCRIPTION

[0050] To make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to specific examples.

[0051] It should be noted that, unless otherwise defined, technical terms or scientific terms used in the present application should be understood as their common meanings to those having ordinary skills in the art to which the present application pertains. The terms "first", "second", and similar terms used in the present application do not represent any order, number, or importance, but are only used to distinguish different components. The terms "include", "contain", and similar terms mean that the components or objects listed before the terms encompass the components or objects listed after the terms and their equivalents, without excluding other components or objects. The terms "connect" or "connected" and similar terms do not mean physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right", and the like only represent relative positional relationships, which can change when the absolute positions of the described objects change.

[0052] Embodiment:

[0053] Please refer to Figures 1-4 The present application provides a technical solution:

[0054] A tunnel surrounding rock grouting reinforcement process simulation analysis method, the specific steps comprising:

[0055] S1: A plurality of evaluation interfaces are set according to a preset interval along the axial direction of the tunnel surrounding rock to be processed, and a monitoring point is selected in each evaluation interface, and a strain signal including axial strain and hoop strain is synchronously collected for each monitoring point.

[0056] In this embodiment, the interval of the evaluation interface is preset according to the geological conditions of the tunnel, the construction progress, and the monitoring requirements. Specifically, one evaluation interface can be set every 50 meters or 100 meters according to the length and complexity of the tunnel. On the axial line of the tunnel, the specific position of each evaluation interface is marked according to the design drawing of the tunnel. The marked position should cover the entire length of the tunnel to ensure the comprehensiveness of the monitoring. A number of monitoring points are selected in each evaluation interface. The number of monitoring points can be determined according to the size of the evaluation interface and the complexity of the surrounding rock. Generally, 3 to 5 monitoring points are selected.

[0057] The strain signal including the axial strain and the hoop strain is synchronously collected for each monitoring point. The specific process is as follows:

[0058] Monitoring points are set at equal intervals along the axis of the surrounding rock, the axial strain at the monitoring points is measured, and the measured value is used as the axial strain of the evaluation interface;

[0059] Monitoring points were set at 45-degree intervals along the circumferential axis of each evaluation interface at the crown and waist locations. The circumferential strain values ​​were measured, and the average of the circumferential strain values ​​at all circumferential locations was taken as the circumferential strain of that evaluation interface.

[0060] By setting monitoring points at equal intervals along the axial direction, monitoring of the entire length of the surrounding rock can be ensured, avoiding omissions of critical areas. Simultaneously, by setting monitoring points at the circumferential axis of symmetry, the environmental and strain characteristics of the surrounding rock can be comprehensively captured. Taking the average circumferential strain value at each evaluation interface effectively eliminates the influence of local outliers, making the acquired data more representative and reflecting the overall strain state of the surrounding rock.

[0061] By setting monitoring points at the crown and waist of the arch, precise measurements can be taken of the main deformation areas of the surrounding rock under stress, obtaining more accurate strain data. By setting monitoring points every 45 degrees in the circumferential direction, the strain changes of the surrounding rock in different directions can be captured, increasing the reliability of the data and the accuracy of the overall analysis. Simultaneous acquisition of axial strain and circumferential strain signals can more quickly identify the deformation trend and potential risks of the surrounding rock, facilitating dynamic monitoring and adjustment.

[0062] S2: Based on the strain signal of each evaluation interface, the volumetric strain of the corresponding evaluation interface is constructed using a linear weighting method. The volumetric strain is used to characterize the compression characteristics of the surrounding rock at the evaluation interface. Furthermore, a volumetric strain hardening index is constructed based on the volumetric strain. The volumetric strain hardening index is used to reflect the change in the mechanical properties of the surrounding rock after compression, and the static viscosity of the grouting material is determined in combination with rheological test parameters.

[0063] In this embodiment, the process of constructing the volumetric strain of each evaluation interface by linear weighting of the strain signal of each evaluation interface is as follows:

[0064] Based on the strain signal at each evaluation interface, a linear weighted average is used to construct the volumetric strain at each evaluation interface:

[0065] ;

[0066] Indicates the first Axial strain at each evaluation interface; Indicates the first Circumferential strain at each evaluation interface; Indicates the first Volumetric strain at each evaluation interface and These represent the weights of axial strain and circumferential strain, respectively, and both are greater than 0. .

[0067] It should be noted that the first Volumetric strain at each evaluation interface The volumetric strain represents the overall deformation state and is used to describe the overall deformation state of a material under stress or external environmental influence. The larger the value of the volumetric strain, the more significant the deformation of the surrounding rock or structure under the action of external forces or geological changes. As the volumetric strain increases, the stability of the surrounding rock gradually decreases, and the risk of potential collapse or deformation failure increases.

[0068] Axial strain and circumferential strain typically play different roles during the stress and deformation of surrounding rock. Using a weighted summation method can better capture the different effects of these two strains on volumetric strain and adapt to the actual behavior of the surrounding rock. Since different surrounding rock conditions may lead to different degrees of influence of axial strain and circumferential strain on volumetric strain, the weights are set to an adjustable form to optimize for different situations and improve the accuracy of the calculation results.

[0069] Among the settings The specific reason is that tunnels or mines bear significant external loads along the axial direction, which causes the deformation of the surrounding rock in the axial direction to dominate. The mechanical properties of the surrounding rock are characterized by low stiffness in the axial direction and more significant deformation. Axial strain contributes more to the overall stability and morphological changes of the surrounding rock, so it needs to be given higher weight.

[0070] When constructing the volumetric strain hardening index based on volumetric strain, the ratio of uniaxial compressive strength to elastic modulus is calculated based on the uniaxial compressive strength and elastic modulus of the surrounding rock as the critical volumetric strain for each evaluation interface. The volumetric strain of each evaluation interface is then compared with the critical volumetric strain to obtain the volumetric strain hardening index, based on the following formula:

[0071] ;

[0072] in, Indicates the first Hardening index of each monitoring section; Indicates the critical volumetric strain; Indicates the uniaxial compressive strength of the surrounding rock; It represents the elastic modulus of the surrounding rock.

[0073] Based on the uniaxial compressive strength and elastic modulus of the surrounding rock, the critical volumetric strain is calculated by the ratio of the two values. This value characterizes the maximum volumetric compressive deformation that the surrounding rock can withstand in the elastic stage. The critical volumetric strain is obtained through monitoring. The actual volumetric strain of each evaluation interface is compared with the critical volumetric strain of the interface, and the hardening index is defined as the ratio between the two, which quantifies the proximity of the surrounding rock compression deformation to the critical state. When the hardening index approaches or exceeds 1, it indicates that the surrounding rock may enter the plastic yield stage, thereby directly reflecting the compression hardening characteristics of the surrounding rock at different evaluation interfaces.

[0074] Through the calculation of the hardening index, the state of the surrounding rock in compression deformation can be quantified, and the stability and bearing capacity of the surrounding rock can be clearly reflected. When the hardening index approaches or exceeds 1, it means that the surrounding rock may enter the plastic yield stage, providing an important early warning signal for the project.

[0075] S3: Based on the volumetric strain hardening index of each evaluation interface and the static viscosity of the grouting material, a strain hardening dynamic coupling method is adopted to obtain the grouting dynamic viscosity coefficient corresponding to the evaluation interface, which is used to describe the rheological properties of the slurry in the reinforcement process with the deformation evolution of the surrounding rock.

[0076] The method for obtaining the static viscosity of the grouting material is as follows: select the grouting material for reinforcement, such as cement slurry, chemical slurry, etc., ensure that its composition and ratio meet the actual engineering requirements, mix the grouting material with water or other solvents according to the designed ratio, ensure that the slurry is fully mixed and uniform, eliminate bubbles and particle sedimentation, form a stable suspension, use a suitable rheometer for slurry testing, such as a rotary rheometer or a reciprocating rheometer to measure the flowability and viscosity of the material, set a series of shear rates from low to high for testing. By changing the shear rate, the flow characteristics and viscosity changes of the slurry can be observed. During the experiment, the rheometer will record the shear stress and shear rate data of the slurry in real time, and the static viscosity value can be obtained according to the rheological equation.

[0077] The method for obtaining the static viscosity of the grouting material is as follows: select the grouting material for reinforcement, such as cement slurry, chemical slurry, etc., ensure that its composition and ratio meet the actual engineering requirements, mix the grouting material with water or other solvents according to the designed ratio, ensure that the slurry is fully mixed and uniform, eliminate bubbles and particle sedimentation, form a stable suspension, use a suitable rheometer for slurry testing, such as a rotary rheometer or a reciprocating rheometer to measure the flowability and viscosity of the material, set a series of shear rates from low to high for testing. By changing the shear rate, the flow characteristics and viscosity changes of the slurry can be observed. During the experiment, the rheometer will record the shear stress and shear rate data of the slurry in real time, and the static viscosity value can be obtained according to the rheological equation.

[0078] Based on the static viscosity and volumetric hardening index of the slurry, the dynamic viscosity coefficient is constructed:

[0079] ;

[0080] wherein, represents the dynamic viscosity coefficient based on the volumetric strain of the first evaluation interface; represents the static viscosity coefficient of the surrounding rock, which is measured by rheological experiment; represents the hardening sensitivity coefficient; represents the power index, which is measured by rheological experiment; represents the first The volume strain hardening index of the evaluation interface.

[0081] It should be noted that the dynamic viscosity coefficient Specifically used to describe the rheological properties of the slurry in the reinforcement process with the deformation evolution of the surrounding rock, the larger the value is, the greater the resistance of the slurry in flowing is, and the weaker the fluidity is;

[0082] Wherein the volume strain hardening index of the surrounding rock Reflects the deformation characteristics of the surrounding rock under the stress state, with the increase of the strain, the fluidity of the slurry is affected by the state of the surrounding rock, therefore, the dynamic viscosity can be described by the volume strain hardening index, in actual engineering, the reaction of the fluid to the surface deformation and stress state is often not linear, therefore, through the power index So that the viscosity changes more in line with the actual flow characteristics under different hardening degrees.

[0083] The static viscosity coefficient , indicating the viscosity of the slurry in the static state, measured by rheological experiment, in the grouting process, the fluidity of the slurry is closely related to the applied force and environmental conditions, through the calculation of the dynamic viscosity coefficient, the changing construction conditions can be better adapted to, and the grouting effect is improved.

[0084] Wherein the hardening sensitivity coefficient Reflects the influence degree of the volume strain hardening index on the dynamic viscosity, which can be set according to the experience of experts.

[0085] S4: According to the obtained dynamic viscosity coefficient, the slurry permeability of the evaluation interface is evaluated by using the exponential decay permeability model, and the grouting pressure correction factor of the evaluation interface is calculated in real time, and the pressure correction factor is used as a correction term of the grouting pressure of the evaluation interface.

[0086] The dynamic construction of the grouting pressure value of each evaluation interface is specifically:

[0087] Based on the dynamic viscosity coefficient, the slurry permeability of the evaluation interface is evaluated by using the exponential decay permeability model, and the grouting pressure correction factor of the evaluation interface is calculated in real time:

[0088] ;

[0089] Wherein,

[0090] ;

[0091] Wherein, The static reference viscosity coefficient is represented by Ks; The reference permeability is represented by K0; The first The penetration rate of each assessment interface; Indicates the first Pressure correction factor for each evaluation interface; This represents the penetration rate attenuation coefficient;

[0092] It should be noted that the first Pressure correction factor for each evaluation interface As a correction term for evaluating the grouting pressure at the interface, it is used to adjust the grouting pressure in real time. The larger the value, the greater the required grouting pressure. The grouting pressure needs to be increased accordingly to overcome the flow resistance and allow the grout to be injected smoothly. This is because the larger the dynamic viscosity coefficient, the greater the resistance during flow and the weaker the fluidity. This means that the flow resistance of the grout in the current state is relatively high, and a larger grouting pressure is required to achieve effective grouting.

[0093] Dynamic viscosity coefficient This indicates the flow characteristics of a slurry under specific volumetric strain conditions. As volumetric strain increases, dynamic viscosity typically increases, leading to decreased slurry fluidity and reduced permeability. The permeability of grout in surrounding rock is usually related to the volumetric strain of the surrounding rock. As the strain increases, the permeability may decrease, leading to reduced fluidity.

[0094] Therefore, by comparing the dynamic viscosity coefficient with the first... Penetration rate of each evaluation interface ratio Characterize fluidity and use a benchmark static viscosity. and benchmark penetration The ratio is set as a standard to determine the grouting pressure correction range based on the difference between the fluidity and the baseline condition.

[0095] Penetration rate ( ) through the exponential decay model and volumetric strain ( Relatedly, when the surrounding rock is subjected to external pressure or deformation, the volume of pores is compressed, leading to a reduction in pore space. This compression narrows the path of fluid through the surrounding rock, increasing flow resistance and thus decreasing permeability. Furthermore, as volumetric strain increases, the pores within the surrounding rock may fracture or lose connectivity due to deformation, causing discontinuities in the water flow channels and further reducing overall permeability. Therefore, it is assumed that permeability decreases exponentially with increasing volumetric strain of the surrounding rock. This reflects the possible changes in the pore structure of the surrounding rock during deformation, which in turn affects the permeability of the grout.

[0096] The pressure correction factor is used as a correction term for the grouting pressure at the evaluation interface to construct the grouting pressure value for each evaluation interface:

[0097] ;

[0098] Indicates the first The grouting pressure value at each evaluation interface. Indicates the first The theoretical baseline pressure value of each evaluation interface is obtained by using the baseline pressure. Multiply by the correction factor The grouting pressure can be dynamically adjusted, allowing for adaptive adjustments to different surrounding rock conditions, including volumetric strain and fluidity, to ensure effective injection of grout at different evaluation interfaces.

[0099] In the simulation analysis of the grouting reinforcement process of tunnel surrounding rock, the theoretical benchmark pressure value of the evaluation interface refers to the grouting pressure that should theoretically be applied to each evaluation interface location under the condition that dynamic factors such as real-time deformation and rheological evolution of the surrounding rock are not considered, based on factors such as the geological characteristics of the surrounding rock, tunnel structural parameters, groundwater pressure, and grouting material performance. This pressure value is usually used as the initial parameter and benchmark reference for reinforcement simulation analysis, providing a basis for subsequent dynamic correction based on the surrounding rock condition.

[0100] There are various methods for obtaining theoretical benchmark pressure values. These typically involve a combination of theoretical calculations, code recommendations, field tests, and numerical simulations. In practical engineering applications, the final determination of the theoretical benchmark pressure value is often the result of a comprehensive evaluation of multiple methods. First, a preliminary pressure range is derived through data analysis and theoretical calculations. Then, this range is corrected based on code recommendations. Finally, field tests are used for verification and optimization. The theoretical benchmark pressure values ​​obtained in this way not only meet engineering safety and reinforcement requirements but also provide a scientific basis for subsequent dynamic pressure correction and simulation analysis based on the surrounding rock mechanical state.

[0101] S5: Based on the grouting pressure correction factor of each evaluation interface, the grouting pressure value of each evaluation interface is dynamically constructed in combination with the theoretical benchmark pressure value. The grouting pressure of any interface in the tunnel axis is determined by linear interpolation method to realize the simulation analysis of the grouting reinforcement process of the tunnel surrounding rock.

[0102] The specific steps for determining the grouting pressure at any interface along the tunnel axis are as follows:

[0103] The preset interval between adjacent evaluation interfaces is The axial interval between adjacent evaluation interfaces is calibrated as ,in Indicates the first The maximum axial range value of each evaluation interface. Indicates the first The minimum axial interval value of each evaluation interface, for any point within the interval. , the grouting pressure value is linearly interpolated according to the axial relative distance:

[0104]

[0105] represent the pressure value when the axial distance is

[0106] By linear interpolation method, the pressure value can be smoothly transitioned between adjacent evaluation interfaces, realizing more continuous pressure distribution, avoiding local stress concentration caused by pressure mutation, and helping to prevent the destruction of surrounding rock and the instability of slurry flow. Linear interpolation can effectively simulate the pressure change at different axial positions of the tunnel , provide more accurate pressure distribution data, which is crucial for actual construction and reinforcement effect evaluation, thereby optimizing the grouting scheme.

[0107] In the process of tunnel surrounding rock grouting reinforcement simulation analysis, the actually obtained grouting pressure data is usually distributed on the pre-set evaluation interface positions. These interfaces are evenly spaced along the axial direction of the tunnel, and each interface has a relatively accurate grouting pressure value. However, in actual engineering design and process control, it is often necessary to understand the grouting pressure distribution at any position along the axial direction of the tunnel in order to optimize reinforcement parameters and conduct safety evaluation in more detail. Due to the limited number of actual measurement points, it is difficult to measure the pressure at all positions, so a reasonable and efficient method is needed to calculate the pressure at any point in the interval.

[0108] The principle of linear interpolation is to give different weights to the pressure values of the two endpoints according to the relative distance of the points in the interval from the two endpoints. Grouting pressure generally does not change dramatically within a short distance, especially in the case of relatively uniform surrounding rock properties and grouting process. Based on this assumption, the pressure values of the two endpoints can be calculated by simple weighted average to calculate the pressure at any position in the interval, making the pressure data smoothly transition in space.

[0109] The use of linear interpolation not only makes up for the information loss caused by the limited number of measurement points, but also provides more continuous and detailed data support for subsequent construction adjustment and risk assessment. It has strong applicability and ease of operation in engineering practice, and is a common means for full-space simulation and analysis of tunnel grouting pressure. This method not only ensures the efficiency of data processing, but also meets the requirements of simulation accuracy in engineering, so it is widely used in related fields of tunnels and underground engineering.

[0110] Please refer to Figure 5 , the present application further provides a tunnel surrounding rock grouting reinforcement process simulation analysis system, the analysis system is used for executing the above-mentioned analysis method, comprising:

[0111] ​​The data acquisition module is configured to set a plurality of evaluation interfaces at preset intervals along an axial direction of the surrounding rock of the tunnel to be processed, and select monitoring points in each evaluation interface, and synchronously acquire strain signals including axial strain and hoop strain for each monitoring point;

[0112] The hardening index construction module is configured to construct a volume strain of the corresponding evaluation interface by using a linear weighting method based on the strain signals of each evaluation interface, use the volume strain to represent compression characteristics of the surrounding rock of the evaluation interface, further construct a volume strain hardening index based on the volume strain, and use the volume strain hardening index to reflect changes in mechanical properties of the surrounding rock after compression, and determine the static viscosity of the grouting material in combination with the rheological test parameters.

[0113] The viscosity coefficient construction module is configured to obtain a grouting dynamic viscosity coefficient of the evaluation interface by using a strain hardening dynamic coupling method based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, and use the grouting dynamic viscosity coefficient to describe rheological characteristics of the slurry in the reinforcement process with the deformation evolution of the surrounding rock.

[0114] The correction factor construction module is configured to evaluate the slurry permeability of the evaluation interface by using an exponential decay permeability model according to the obtained dynamic viscosity coefficient, further calculate a grouting pressure correction factor of the evaluation interface in real time, and use the pressure correction factor as a correction term of the grouting pressure of the evaluation interface.

[0115] The interpolation simulation module is configured to dynamically construct the grouting pressure value of each evaluation interface based on the grouting pressure correction factor of each evaluation interface in combination with a theoretical reference pressure value, and determine the grouting pressure of any interface in the axial direction of the tunnel by using a linear interpolation method to simulate and analyze the grouting reinforcement process of the surrounding rock of the tunnel.

[0116] The above formulas are all dimensionless numerical calculations, the formulas are obtained by software simulation of a large amount of data to obtain a formula closest to the actual situation, and the preset parameters in the formulas are set by a person skilled in the art according to the actual situation.

[0117] The above embodiments can be realized by software, hardware, firmware or any combination thereof, in whole or in part. When realized by software, the above embodiments can be realized in the form of a computer program product in whole or in part. A person skilled in the art can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized by hardware or software methods depends on the specific application and design constraints of the technical solutions.

[0118] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, and may be located in one place, or distributed on multiple network units. Part or all of the units can be selected to achieve the purpose of the embodiment of the present application according to actual needs.

[0119] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for simulating and analyzing the process of grouting reinforcement of tunnel surrounding rock, characterized in that the steps of The method comprises the following steps: S1: multiple evaluation interfaces are arranged along the axial direction of the surrounding rock of the tunnel to be processed at a preset interval, and monitoring points are selected in each evaluation interface, and strain signals including axial strain and hoop strain are synchronously collected for each monitoring point; S2: based on the strain signals of each evaluation interface, a linear weighting method is used to construct the volume strain of the corresponding evaluation interface, the volume strain is used to represent the compression characteristics of the surrounding rock of the evaluation interface, and a volume strain hardening index is further constructed based on the volume strain, the volume strain hardening index is used to reflect the change of the mechanical properties of the surrounding rock after compression, and the static viscosity of the grouting material is determined in combination with the rheological test parameters; S3: based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, a strain hardening dynamic coupling method is used to obtain the grouting dynamic viscosity coefficient corresponding to the evaluation interface, and the grouting dynamic viscosity coefficient is used to describe the rheological characteristics of the slurry in the reinforcement process with the deformation evolution of the surrounding rock; S4: according to the obtained dynamic viscosity coefficient, an exponential decay permeability model is used to evaluate the slurry permeability of the evaluation interface, and then the grouting pressure correction factor of the evaluation interface is calculated in real time, and the pressure correction factor is used as a correction term for the grouting pressure of the evaluation interface; S5: based on the grouting pressure correction factor of each evaluation interface, the grouting pressure values of the evaluation interfaces are dynamically constructed in combination with the theoretical reference pressure value, and a linear interpolation method is used to determine the grouting pressure of any interface in the axial direction of the tunnel to realize the simulation analysis of the grouting reinforcement process of the surrounding rock of the tunnel; The synchronous collection of strain signals including axial strain and hoop strain for each monitoring point comprises the following steps: The monitoring points are arranged at equal intervals along the axial direction of the surrounding rock, the axial strain at the monitoring points is measured, and the measured value is taken as the axial strain of the evaluation interface; Monitoring points are arranged at every 45 degrees along the hoop direction at the crown and haunch position regions of the symmetric axis of each evaluation interface, the hoop strain values are measured, and the average value of the hoop strain values of all hoop positions is taken as the hoop strain of the evaluation interface; When the volume strain hardening index is constructed based on the volume strain, the ratio of the uniaxial compressive strength to the elastic modulus is calculated as the critical volume strain of each evaluation interface according to the uniaxial compressive strength and the elastic modulus of the surrounding rock, and the volume strain hardening index is obtained by taking the ratio of the volume strain to the critical volume strain of each evaluation interface; Based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, a strain hardening dynamic coupling method is used to obtain the grouting dynamic viscosity coefficient corresponding to the evaluation interface, and the formula is as follows: in, Indicates based on the first The dynamic viscosity coefficient of the volumetric strain at the evaluation interface; This represents the static viscosity coefficient of the surrounding rock. This is expressed as the hardening sensitivity coefficient; Indicates the power exponent; Indicates the first Volumetric strain hardening index of each evaluation interface; Indicates the first The volumetric strain of each evaluation interface.

2. The method according to claim 1, characterized in that, For the strain signals of each evaluation interface, a linear weighting method is used to construct the volume strain of each evaluation interface, and the specific process is as follows: Based on the strain signals of each evaluation interface, a linear weighting method is used to construct the volume strain of each evaluation interface; an axial strain of the first evaluation interface; an axial strain of the first evaluation interface; a hoop strain of the first evaluation interface, a hoop strain of the first evaluation interface, a volumetric strain of the first evaluation interface; a volumetric strain of the first evaluation interface; and respectively represent an axial strain, a hoop strain weight and are both greater than 0, .

3. The method according to claim 2, characterized in that, When the grouting pressure values of the evaluation interfaces are dynamically constructed, the slurry permeability of the evaluation interface is evaluated based on the dynamic viscosity coefficient by using an exponential decay permeability model, and then the grouting pressure correction factor of the evaluation interface is calculated in real time, and the formula is as follows: Wherein: wherein, represents a static viscosity coefficient of the surrounding rock; represents a reference permeability; represents a permeability of the evaluation interface; represents a pressure correction factor of the evaluation interface; represents a permeability decay coefficient; The pressure correction factor is used as a correction term of the grouting pressure of the evaluation interface to construct the grouting pressure value of each evaluation interface: represents a grouting pressure value of the evaluation interface, represents a theoretical reference pressure value of the evaluation interface.

4. The method according to claim 3, characterized in that, The specific steps for determining the grouting pressure of any interface in the axial direction of the tunnel are as follows: The preset interval of adjacent evaluation interfaces is The axial interval between adjacent evaluation interfaces is calibrated as Wherein represents the axial maximum interval value of the first evaluation interface, represents the axial minimum interval value of the first evaluation interface, for any point in the interval , the grouting pressure value is linearly interpolated according to the axial relative distance: denotes the pressure value at an axial distance of denotes the pressure value at an axial distance of 5. A tunnel surrounding rock grouting reinforcement process simulation analysis system, characterized in that: The analysis system is used to perform the analysis method of any one of claims 1-4, comprising: A data acquisition module is configured to set a plurality of evaluation interfaces at a preset interval along the axial direction of the surrounding rock of the tunnel to be processed, and select a monitoring point in each evaluation interface, and synchronously acquire strain signals including axial strain and hoop strain for each monitoring point; A hardening index construction module is configured to construct a volume strain of the corresponding evaluation interface by using a linear weighting method based on the strain signals of each evaluation interface, use the volume strain to represent the compression characteristics of the surrounding rock of the evaluation interface, further construct a volume strain hardening index based on the volume strain, and use the volume strain hardening index to reflect the change in mechanical properties of the surrounding rock after compression, and determine the static viscosity of the grouting material in combination with the rheological test parameters; A viscosity coefficient construction module is configured to obtain the grouting dynamic viscosity coefficient of the evaluation interface by using a strain hardening dynamic coupling method based on the volume strain hardening index of each evaluation interface and the static viscosity of the grouting material, and use the grouting dynamic viscosity coefficient to describe the rheological properties of the grout in the reinforcement process with the deformation evolution of the surrounding rock; A correction factor construction module is configured to evaluate the grout permeability of the evaluation interface by using an exponential decay permeability model according to the obtained dynamic viscosity coefficient, and further calculate the grouting pressure correction factor of the evaluation interface in real time, and use the pressure correction factor as a correction term of the grouting pressure of the evaluation interface; An interpolation simulation module is configured to dynamically construct the grouting pressure value of each evaluation interface based on the grouting pressure correction factor of each evaluation interface and the theoretical reference pressure value, and determine the grouting pressure of any interface in the axial direction of the tunnel by using a linear interpolation method to realize the simulation analysis of the grouting reinforcement process of the surrounding rock of the tunnel.

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