Partition targeted control method based on power exponential deformation distribution rule of fractured surrounding rock

Abstract

The invention discloses a partition targeted control method based on a power exponential deformation distribution rule of fractured surrounding rock. Theoretical calculation is carried out based on roadway data, FDEM simulation is matched with field testing, and the range of the surrounding rock loosening circle is determined; through multi-point displacement meter monitoring and FDEM simulation calculation, roadway surrounding rock deformation distribution data are obtained, and curve fitting is carried out on a roadway surrounding rock deformation distribution rule based on a power exponential function; in combination with the two-eight distribution property of a power exponential function, secondary partitioning is carried out on the loose circle range according to the surrounding rock deformation, and surrounding rock deformation difference sources and dominant factors are distinguished; and the structure and the grouting radius of the surrounding rock targeted control anchor rod (cable) in different directions of the roadway are determined, and zoned targeted control over the surrounding rock of the roadway is achieved. According to the method, surrounding rock in the range of a loose circle is divided into a crushing and swelling deformation area and a shearing and sliding area according to the deformation amount of the broken surrounding rock, the surrounding rock control mode or the anchor rod (cable) structure, the arrangement length and the arrangement direction are adjusted in a targeted mode, and partition targeted control over the roadway surrounding rock is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of engineering rock mass, and in particular to a partitioned targeted control method based on the power exponential deformation distribution law of fractured surrounding rocks. Background Art

[0002] During underground mining of coal resources, the excavation of tunnels will expose free surfaces in stable strata, causing the redistribution of surrounding geostress and destroying the three-dimensional stress state of the surrounding rock, causing deformation, damage and instability of the surrounding rock. In this process, affected by factors such as the geostress environment, surrounding rock lithology and mining disturbance, the tunnel surrounding rock develops a significant directional and regional tensile-shear fracture network.

[0003] As the depth of coal resources being mined continues to increase, tunnels are easily affected by high deviatoric stress and strong mining, resulting in large-scale caving or local large deformation. Surrounding rock control, reinforcement and maintenance are becoming increasingly difficult, and the cost of surrounding rock stability control is gradually increasing. In existing tunnel surrounding rock control schemes, most of them limit the deformation of surrounding rock in the macro-loosening damage zone by suspending, combining and compressing the rock mass with anchors (cables). The inherent connection between surrounding rock rupture and tunnel deformation is not fully considered, the surrounding rock zoning in the macro-loosening damage zone is unclear, and there is a lack of clear and scientific definition standards, resulting in the homogenization and empiricism of tunnel surrounding rock support methods. At present, the tunnel surrounding rock control methods provided by the loosening circle theory mostly select control methods and control parameters for the overall range of the tunnel loosening circle, ignoring the differences in the development range and expansion mechanism of tensile shear fractures within the loosening circle, resulting in difficulty in determining surrounding rock control parameters such as grouting range, anchor (cable) length, and direction. Summary of the invention

[0004] The purpose of the present invention is to provide a partitioned targeted control method based on the power exponential deformation distribution law of the fractured surrounding rock in order to solve the above technical problems. In order to solve the above technical problems, the present invention adopts the following technical solutions: A partitioned targeted control method based on the power exponential deformation distribution law of fractured surrounding rock comprises the following steps: (1) Investigate the geological and mining data of the pre-supported tunnel to determine the geological structure and mining disturbance around the tunnel; (2) The direction and magnitude of the ground stress around the roadway were determined by the stress relief method. Based on the double jack method, in-situ testing was carried out on the coal and rock mass within 4.5 times the roadway radius of the roadway roof and floor to determine the type of coal and rock mass and in-situ mechanical parameters of the roadway roof and floor. (3) Based on the tunnel surrounding rock parameters and ground stress environment determined in steps (1) and (2), the range of the tunnel loose zone is calculated using the loose zone theory. At the same time, a FDEM numerical model is established and combined with the detection results of the tunnel surrounding rock loose zone detector to determine the development range of the tunnel loose zone; (4) Divide the tunnel section into eight directions and install DW multi-point displacement meters to monitor the deformation distribution of the tunnel surrounding rock. The farthest point of the multi-point displacement meter is 1.5 times the range of the tunnel loosening circle. The multi-point displacement meters are evenly arranged in each direction, and the number of displacement meter monitoring points is not less than 5; (5) Establish a FDEM numerical model to calculate and analyze the fracture and deformation state of the surrounding rock. Through the measurement lines arranged in the model, obtain the radial deformation distribution data of the tunnel surrounding rock; (6) Based on the power exponential function model The radial deformation distribution data of surrounding rock in different directions of the roadway in the FDEM numerical model and the surrounding rock deformation distribution data obtained by the multi-point displacement meter in the roadway are fitted respectively. By adjusting the FDEM model operation process, the constants A and B in the fitting curves obtained by the simulation and the multi-point displacement meter monitoring are close, and the fitting curves are approximately overlapped. At this time, the surrounding rock fracture deformation state of the FDEM numerical model is close to the deformation and fracture state of the surrounding rock in the actual roadway at the corresponding position. (7) According to the "28 distribution" property of the power exponential function, "80%" of the deformation of the tunnel is concentrated in the shallow "20%" surrounding rock. Therefore, based on the loosening zone theory, the range corresponding to 0.2 times the maximum deformation of the surrounding rock is defined as the "crushing and swelling deformation zone" of the surrounding rock, and the loosening zone of the tunnel excluding the "crushing and swelling deformation zone" is defined as the "shear slip zone"; (8) When the radius of the surrounding rock "crushed expansion zone" is smaller than the radius of the loosening zone, the deformation of the surrounding rock in this direction of the tunnel is mainly affected by the crushed expansion deformation of the shallow surrounding rock and the sliding deformation of the deep surrounding rock. At this time, the range of the "crushed expansion zone" is the main grouting reinforcement range. During the anchor rod and cable support process, its length needs to be greater than the radius of the rupture zone. At the same time, by changing the structure and material of the anchor rod and cable, the shear deformation resistance of the anchor rod and cable in the "shear sliding zone" section is improved. By increasing the preload and changing the structure and material of the anchor rod and cable, the anchoring effect of the anchor rod and cable in the "crushed expansion zone" section is improved; (9) Affected by the ground stress environment and the lithology of the surrounding rock, the fracture network in some areas of the tunnel is small and the surrounding rock is relatively complete. At this time, the radius of the surrounding rock "crushed expansion deformation zone" determined by the fitting calculation is larger than the radius of the loosening circle. The deformation of the surrounding rock in this direction of the tunnel is mainly affected by the crushed expansion deformation of the shallow surrounding rock and the overall movement deformation of the deep surrounding rock. At this time, the "crushed expansion deformation zone" is the main grouting reinforcement range, and the long anchor cable plays a suspension role to control the deformation of the surrounding rock; (10) Through secondary zoning of the loose zone of the surrounding rock of the tunnel section, the radius of the "crushing deformation zone" and "shear slip zone" of the tunnel surrounding rock in different directions is obtained, the difference in the source of deformation of the surrounding rock in different directions of the tunnel section is determined, and the optimization selection of the tunnel grouting radius, grouting materials and support methods, support length and support structure is guided. Finally, a zoning targeted control method based on the power exponential deformation distribution law of the fractured surrounding rock is constructed; (11) Real-time monitoring of the deformation and damage evolution of the tunnel surrounding rock after support. The MYJ-20 anchor cable dynamometer is used to test the stress of the anchor cables. Once the tunnel has local large deformation, damage or anchor cable anchor failure, the corresponding position is reinforced in time to maintain the stability of the tunnel.

[0005] Furthermore, the geological structure occurrence state around the tunnel includes folds, bedding, and joints.

[0006] Furthermore, the mining disturbance conditions include excavation of nearby working faces, tunnel layout and chamber distribution.

[0007] Furthermore, the in-situ mechanical parameters include the elastic modulus E d ,tensile strength , compressive strength , shear strength , cohesion C , internal friction angle F .

[0008] The present invention has significant technical effects due to the adoption of the above technical solutions: (1) Based on the loosening zone theory, this method realizes the secondary partitioning of the loosening zone of the tunnel surrounding rock through theoretical calculation, FDEM numerical simulation and field testing, points out the difference in deformation factors of the surrounding rock in different directions of the tunnel, clarifies the selection method of the surrounding rock control method and support parameters, and effectively controls the cost of repeated support of the surrounding rock under large deformation of the tunnel. (2) This method integrates mathematical theory and the law of surrounding rock fracture and deformation, and based on the "28 distribution" property of the surrounding rock power exponential deformation distribution law, quantifies the mathematical standard of the secondary partitioning of the fracture range of the loosening zone of the surrounding rock, points out the fracture and deformation differences of the surrounding rock in different partitions of the loosening zone, determines the dominant factors of surrounding rock control in different partitions, and guides the selection of surrounding rock-specific targeted control methods and control parameters. (3) This method fully considers the differences in the development mechanism and extension range of tension-shear fracture in the surrounding rock. Based on the power exponential deformation distribution law of the fractured surrounding rock, it reveals the role of anchors (cables) in different fracture zones and the corresponding improvement methods, refines the selection of surrounding rock control methods and control parameters, and provides theoretical support for the design of specific anchors and the determination of grouting range for zoned targeted support. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a technical roadmap of the partitioned targeted control method based on the power exponential deformation distribution law of the fractured surrounding rock in the present invention; Figure 2 The surrounding rock fracture state of the loosening zone theory in the present invention (taking surrounding rocks with different internal friction coefficients as examples); Figure 3 This is a schematic diagram of the surrounding rock zoning in the loosening zone of the present invention (taking surrounding rocks with different internal friction coefficients as an example). DETAILED DESCRIPTION

[0010] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0011] In the description of the present invention, it should be noted that the terms "vertical", "upper", "lower", "horizontal", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, "first", "second", "third", and "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0012] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, it can be a mechanical connection, it can be an electrical connection, it can be a direct connection, it can be connected through an intermediate medium, and it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0013] like Figure 1 As shown, a partitioned targeted control method based on the power exponential deformation distribution law of fractured surrounding rock in the present invention involves the following steps: (1) Investigate the geological and mining data of the pre-supported tunnel to determine the geological structure and mining disturbance around the tunnel; (2) The direction and magnitude of the ground stress around the roadway were determined by the stress relief method. Based on the double jack method, in-situ testing was carried out on the coal and rock mass within 4.5 times the roadway radius of the roadway roof and floor to determine the type of coal and rock mass and in-situ mechanical parameters of the roadway roof and floor. (3) Based on the tunnel surrounding rock parameters and ground stress environment determined in steps (1) and (2), the range of the tunnel loose zone is calculated using the loose zone theory. At the same time, a FDEM numerical model is established and combined with the detection results of the tunnel surrounding rock loose zone detector to determine the development range of the tunnel loose zone. Figure 2 As shown in the figure, the numerical calculation results of the FDEM model of surrounding rock with different internal friction coefficients are used as an example to define the scope of the tunnel fracture zone. -stress, - Friction coefficient of surrounding rock Tan φ= Stress distribution curve at 0.4, - Friction coefficient of surrounding rock Tan φ= Stress distribution curve at 0.1, P-original rock stress, b1-internal friction coefficient of surrounding rock Tan φ= 0.4: radius of the roadway fracture zone, b2- friction coefficient of surrounding rock Tan φ= When the value is 0.1, the radius of the roadway fracture zone, and the coordinate axis 3 and 4 quadrants are the friction coefficient Tan in the surrounding rock. φ= 0.4 Distribution of surrounding rock stress and surrounding rock tensile shear fracture distribution, coordinate axis 1 and 2 quadrants are the friction coefficient Tan of surrounding rock φ= 0.1 surrounding rock stress distribution and surrounding rock tensile shear fracture distribution; (4) Divide the tunnel section into eight directions and install DW multi-point displacement meters to monitor the deformation distribution of the tunnel surrounding rock. The farthest point of the multi-point displacement meter is 1.5 times the range of the tunnel loosening circle. The multi-point displacement meters are evenly arranged in each direction, and the number of displacement meter monitoring points is not less than 5; (5) Establish a FDEM numerical model to calculate and analyze the fracture and deformation state of the surrounding rock. Through the measurement lines arranged in the model, obtain the radial deformation distribution data of the tunnel surrounding rock; (6) Based on the power exponential function model The radial deformation distribution data of surrounding rock in different directions of the roadway in the FDEM numerical model and the surrounding rock deformation distribution data obtained by the multi-point displacement meter in the roadway are fitted respectively. By adjusting the FDEM model operation process, the constants A and B in the fitting curves obtained by the simulation and the multi-point displacement meter monitoring are close, and the fitting curves are approximately overlapped. At this time, the surrounding rock fracture deformation state of the FDEM numerical model is close to the deformation and fracture state of the surrounding rock in the actual roadway at the corresponding position. (7) According to the "28 distribution" property of the power exponential function, "80%" of the deformation of the tunnel is concentrated in the shallow "20%" surrounding rock. Therefore, based on the loosening zone theory, it is stipulated that the range corresponding to 0.2 times the maximum deformation of the surrounding rock is the surrounding rock "fragmentation and expansion deformation zone" (the surrounding rock deformation is affected by the development of shallow tensile fractures or tensile-shear mixed fractures and deep shear fractures, and is the result of the combined action of shallow surrounding rock fragmentation and expansion deformation and deep surrounding rock shear slip). The tunnel loosening zone excluding the "fragmentation and expansion deformation zone" is the "shear slip zone" (the surrounding rock is mainly affected by the development of shear fractures, with shear slip as the main feature). Figure 3 As shown in the figure, taking the numerical calculation results of the FDEM model of surrounding rock with different internal friction coefficients as an example, the tunnel fracture area is secondary divided according to the maximum deformation of the surrounding rock, where - Friction coefficient of surrounding rock Tan φ= The maximum displacement of surrounding rock when 0.1, - Friction coefficient of surrounding rock Tan φ= The maximum displacement of surrounding rock when 0.4, - Friction coefficient of surrounding rock Tan φ= When 0.1, the boundary of the roadway expansion deformation zone is calculated based on the "28 distribution" property of the power exponential function. - Friction coefficient of surrounding rock Tan φ= When 0.4, the boundary of the tunnel expansion deformation zone is calculated based on the "28 distribution" property of the power exponential function, a1-the friction coefficient of the surrounding rock Tan φ= 0.4: radius of the tunnel expansion deformation zone, a2- friction coefficient of surrounding rock Tan φ= 0.1: radius of deformation zone of tunnel expansion, b1- friction coefficient of surrounding rock Tan φ= 0.4: radius of the roadway fracture zone, b2- friction coefficient of surrounding rock Tan φ= When the value is 0.1, the radius of the roadway fracture zone, and the coordinate axis 3 and 4 quadrants are the friction coefficient Tan in the surrounding rock. φ= 0.4 Distribution of surrounding rock displacement and surrounding rock tensile shear fracture distribution, coordinate axis 1 and 2 quadrants are the surrounding rock internal friction coefficient Tan φ= 0.1 Distribution of surrounding rock displacement and surrounding rock tensile shear fracture distribution; (8) When the radius of the surrounding rock "crushed expansion zone" is smaller than the radius of the loosening zone, the deformation of the surrounding rock in this direction of the tunnel is mainly affected by the crushed expansion deformation of the shallow surrounding rock and the sliding deformation of the deep surrounding rock. At this time, the range of the "crushed expansion zone" is the main grouting reinforcement range. During the anchor (cable) support process, its length needs to be greater than the radius of the rupture zone. At the same time, by changing the structure and material of the anchor (cable), the shear deformation resistance of the anchor (cable) in the "shear sliding zone" section is improved. By increasing the preload and changing the structure and material of the anchor (cable), the anchoring effect of the anchor (cable) in the "crushed expansion zone" section is improved; (9) Affected by the ground stress environment and the lithology of the surrounding rock, the fracture network in some areas of the tunnel is small and the surrounding rock is relatively complete. At this time, the radius of the surrounding rock "crushed expansion deformation zone" determined by the fitting calculation is larger than the radius of the loosening circle. The deformation of the surrounding rock in this direction of the tunnel is mainly affected by the crushed expansion deformation of the shallow surrounding rock and the overall movement deformation of the deep surrounding rock. At this time, the "crushed expansion deformation zone" is the main grouting reinforcement range, and the long anchor cable plays a suspension role to control the deformation of the surrounding rock; (10) Through secondary zoning of the loose zone of the surrounding rock of the tunnel section, the radius of the "crushing deformation zone" and "shear slip zone" of the tunnel surrounding rock in different directions is obtained, the difference in the source of deformation of the surrounding rock in different directions of the tunnel section is determined, and the optimization selection of the tunnel grouting radius, grouting materials and support methods, support length and support structure is guided. Finally, a zoning targeted control method based on the power exponential deformation distribution law of the fractured surrounding rock is constructed; (11) Real-time monitoring of the deformation and damage evolution of the tunnel surrounding rock after support. The MYJ-20 anchor bolt and cable dynamometer is used to test the force of the anchor bolt (cable). Once the tunnel has local large deformation, damage or anchor bolt (cable) anchor failure, the corresponding position is reinforced in time to maintain the stability of the tunnel.

[0014] The geological structure conditions around the tunnel include folds, bedding, and joints; the mining disturbance conditions include excavation of nearby working faces, tunnel layout, and chamber distribution.

[0015] The in-situ mechanical parameters include the elastic modulus E d ,tensile strength , compressive strength , shear strength , cohesion C , internal friction angle F .

[0016] The invention patent discloses a zoning targeted control method based on the power exponential deformation distribution law of fractured surrounding rock. In the process of underground mining of coal resources, the excavation of the tunnel will expose the free surface in the stable stratum, causing the surrounding ground stress to be redistributed and destroying the three-dimensional stress state of the surrounding rock, causing the surrounding rock to deform, destroy and become unstable. In this process, affected by factors such as the ground stress environment, the rock properties of the surrounding rock and the mining disturbance, the tunnel surrounding rock develops a significant directional and regional tensile shear fracture network. Through the investigation of mining site data, on-site tests and rock mechanics tests, the ground stress conditions, coal rock parameters and geological structure distribution of the tunnel were obtained; based on the obtained parameters, theoretical calculations, FDEM numerical simulations and on-site tests were carried out to determine the range of the loosening zone of the tunnel surrounding rock; through multi-point displacement meter monitoring and FDEM simulation calculations, the deformation distribution data of the tunnel surrounding rock were obtained, and the deformation distribution law of the tunnel surrounding rock was curve fitted based on the power exponential function; combined with the "28 distribution" property of the power exponential function, the loosening zone range was secondary partitioned according to the deformation of the surrounding rock, the sources and dominant factors of the deformation differences of the surrounding rock in different directions of the tunnel were distinguished, and the surrounding rock control method and support parameters were determined; based on the targeted support parameters, the targeted control anchor (cable) structure and grouting radius of the surrounding rock in different directions of the tunnel were determined to achieve zoned targeted control of the tunnel surrounding rock. This method is based on the directional and regional differences in the development of tensile-shear fractures in the tunnel surrounding rock. Through field measurements, FDEM numerical analysis and theoretical calculations, combined with the characteristic that the deformation and fracture process of the surrounding rock conforms to the "28 distribution" property of the power exponential function, the surrounding rock in the loosening zone of the tunnel is divided into a crushing and swelling deformation zone and a shear slip zone according to the deformation amount of the fractured surrounding rock. On this basis, the radius of the crushing and swelling deformation zone of the surrounding rock in different directions of the tunnel is compared with the radius of the macroscopic fracture zone, the dominant factors of the surrounding rock deformation in different directions are determined, and the surrounding rock control method or the anchor (cable) structure, layout length and layout direction are adjusted in a targeted manner, which provides a theoretical basis for the selection and determination of the zone-specific targeted control parameters of the tunnel surrounding rock.

[0017] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0018] The above-described embodiments only express the implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention of the present invention. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention of the present invention shall be subject to the attached claims.

Claims

1. A partition-targeted control method based on the power exponential deformation distribution law of fractured surrounding rock, characterized in that: The following steps are involved: (1) Investigate the geological and mining data of the pre-supported tunnel to determine the geological structure and mining disturbance around the tunnel; (2) The direction and magnitude of the ground stress around the roadway were determined by the stress relief method. Based on the double jack method, in-situ testing was carried out on the coal and rock mass within 4.5 times the roadway radius of the roadway roof and floor to determine the type of coal and rock mass and in-situ mechanical parameters of the roadway roof and floor. (3) Based on the tunnel surrounding rock parameters and ground stress environment determined in steps (1) and (2), the range of the tunnel loose zone is calculated using the loose zone theory. At the same time, a FDEM numerical model is established and combined with the detection results of the tunnel surrounding rock loose zone detector to determine the development range of the tunnel loose zone; (4) Divide the tunnel section into eight directions and install DW multi-point displacement meters to monitor the deformation distribution of the tunnel surrounding rock. The farthest point of the multi-point displacement meter is 1.5 times the range of the tunnel loosening circle. The multi-point displacement meters are evenly arranged in each direction, and the number of displacement meter monitoring points is not less than 5; (5) Establish a FDEM numerical model to calculate and analyze the fracture and deformation state of the surrounding rock. Through the measurement lines arranged in the model, obtain the radial deformation distribution data of the tunnel surrounding rock; (6) Based on the power exponential function model The radial deformation distribution data of surrounding rock in different directions of the roadway in the FDEM numerical model and the surrounding rock deformation distribution data obtained by the multi-point displacement meter in the roadway are fitted respectively. By adjusting the FDEM model operation process, the constants A and B in the fitting curves obtained by the simulation and the multi-point displacement meter monitoring are close, and the fitting curves are approximately overlapped. At this time, the surrounding rock fracture deformation state of the FDEM numerical model is close to the deformation and fracture state of the surrounding rock in the actual roadway at the corresponding position. (7) According to the "28 distribution" property of the power exponential function, "80%" of the deformation of the tunnel is concentrated in the shallow "20%" surrounding rock. Therefore, based on the loosening zone theory, the range corresponding to 0.2 times the maximum deformation of the surrounding rock is defined as the "crushing and swelling deformation zone" of the surrounding rock, and the loosening zone of the tunnel excluding the "crushing and swelling deformation zone" is defined as the "shear slip zone"; (8) When the radius of the surrounding rock "crushed expansion deformation zone" is smaller than the radius of the loosening zone, the deformation of the surrounding rock in this direction of the tunnel is mainly affected by the crushed expansion deformation of the shallow surrounding rock and the sliding deformation of the deep surrounding rock; at this time, the range of the "crushed expansion deformation zone" is the main grouting reinforcement range. During the anchor rod and cable support process, its length needs to be greater than the radius of the rupture zone. At the same time, by changing the structure and material of the anchor rod and cable, the shear deformation resistance of the anchor rod and cable in the "shear sliding zone" section is improved. By increasing the preload and changing the structure and material of the anchor rod and cable, the anchoring effect of the anchor rod and cable in the "crushed expansion deformation zone" section is improved; (9) Affected by the ground stress environment and the lithology of the surrounding rock, the fracture network in some areas of the roadway is small and the surrounding rock is relatively complete. At this time, the radius of the surrounding rock "fragmentation and expansion deformation zone" determined by the fitting calculation is larger than the radius of the loosening circle. The deformation of the surrounding rock in this direction of the roadway is mainly affected by the fragmentation and expansion deformation of the shallow surrounding rock and the overall movement deformation of the deep surrounding rock. At this time, the "fragmentation and expansion deformation zone" is the main grouting reinforcement range, and the long anchor cable plays a suspension role to control the deformation of the surrounding rock. (10) Through secondary zoning of the loose zone of the surrounding rock of the tunnel section, the radius of the "crushing deformation zone" and "shear slip zone" of the tunnel surrounding rock in different directions is obtained, the difference in the source of deformation of the surrounding rock in different directions of the tunnel section is determined, and the optimization selection of the tunnel grouting radius, grouting materials and support methods, support length and support structure is guided. Finally, a zoning targeted control method based on the power exponential deformation distribution law of the fractured surrounding rock is constructed; (11) Real-time monitoring of the deformation and damage evolution of the tunnel surrounding rock after support; using the MYJ-20 anchor cable dynamometer to test the stress of the anchor rods and cables. Once the tunnel has local large deformation, damage or anchor failure, the corresponding position will be reinforced in time to maintain the stability of the tunnel.

2. According to claim 1, a partitioned targeted control method based on the power exponential deformation distribution law of fractured surrounding rock is characterized by: The geological structure conditions around the tunnel include folds, bedding and joints.

3. According to claim 1, a partitioned targeted control method based on the power exponential deformation distribution law of fractured surrounding rock is characterized by: The mining disturbance conditions include excavation of nearby working faces, tunnel layout and chamber distribution.

4. The method for zone-based targeted control based on the power exponential deformation distribution law of fractured surrounding rock according to claim 1, characterized in that: The in-situ mechanical parameters include the elastic modulus E d ,tensile strength , compressive strength , shear strength , cohesion C , internal friction angle Φ .

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