CN115164661A - Directional energy gathering ring and tunnel surrounding rock stress relieving blasting method - Google Patents

Abstract

The invention discloses a directional energy-gathering ring and a tunnel surrounding rock stress relief blasting method. According to the directional energy-gathering ring provided by the invention, the blasting energy is released from the through holes during blasting so as to realize blasting of the stress-relieving blasting holes, and the blasting energy is easy to damage the ring body from the energy-gathering grooves and further release the energy, so that the energy released by the through holes and the energy-gathering grooves forms net-shaped cutting on the stress-relieving blasting holes, the stress-relieving blasting holes are uniformly damaged, the stress of a high-stress concentrated area of the surrounding rock of the tunnel is better released, the occurrence of rock burst is effectively prevented, and the safety of constructors and equipment and the construction progress are ensured to be carried out according to a plan.

Description

Directional energy gathering ring and tunnel surrounding rock stress relief blasting method

technical field

The invention relates to the technical field of geotechnical engineering, in particular to a directional energy gathering ring and a stress relief blasting method for tunnel surrounding rock.

Background technique

Rockburst is a severe dynamic damage phenomenon that occurs in the surrounding rock during the excavation of deep underground caverns or deep mining in the fields of water conservancy and hydropower engineering, transportation, and mining. And with the sudden release of the strain energy of the compressed rock, it is often a dynamic phenomenon in the form of rock fragment ejection, massive rock collapse or mine shock, which can cause serious damage to the excavation face, equipment damage and casualties. The construction progress will also cause problems such as over-excavation and initial support failure. At present, the prevention method of tunnel rock burst is to place explosives after drilling the surrounding rock of the tunnel for blasting. However, blasting directly in the surrounding rock hole, the energy is too concentrated, and the damage degree of the surrounding rock hole is uneven, which leads to the rock formation of the surrounding rock of the tunnel. The explosion prevention effect is poor.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to propose a blasting method for directional energy gathering ring and tunnel surrounding rock stress relief, aiming to solve the problem of direct blasting in the surrounding rock hole, the energy is too concentrated, the damage degree of the surrounding rock hole is uneven, and the surrounding rock of the tunnel is caused by blasting. The problem of poor rockburst prevention effect.

In order to achieve the above purpose, the present invention proposes a directional energy-gathering ring, which is used for stress relief blasting of rock mass. There are multiple energy collecting grooves, and they are arranged at intervals along the circumferential direction. The ring body has an energy releasing area located between two adjacent energy collecting grooves. The energy zone is provided with a plurality of through holes, and the plurality of through holes are arranged in sequence along the length direction of the ring body.

The present invention also proposes a stress relief blasting method for tunnel surrounding rock, comprising the following steps:

Determining stress distribution parameters of the surrounding rock in the tunnel face region, wherein the stress distribution parameters include the spatial position of stress concentration and the stress value;

Determining the spatial position of the stress concentration greater than the preset stress value as the spatial position of the stress concentration to be blasted;

Drilling a stress relief blast hole at the spatial position where the stress to be blasted is concentrated;

Correspondingly, a directional energy-gathering ring is arranged in the stress relief blasting hole, wherein the directional energy-gathering ring is set as the above-mentioned directional energy-gathering ring;

Explosives are arranged in the directional energy gathering ring for directional blasting.

Optionally, the step of "determining the stress distribution parameters of the surrounding rock in the tunnel face region" includes:

Obtain the engineering geological parameters of the tunnel surrounding rock to be blasted to dissipate energy;

Establish a three-dimensional numerical computing network model for simulating the tunnel excavation process;

In the three-dimensional numerical calculation software, the three-dimensional numerical calculation network model is processed and set with engineering geological parameters as constraints, so as to simulate the construction process of tunnel excavation and support;

According to the computer simulation results of the construction process of tunnel excavation and support, the stress characteristics of the surrounding rock in the tunnel face area are analyzed, and the stress distribution parameters of the surrounding rock in the tunnel face area are determined.

Optionally, the engineering geological parameters include initial in-situ stress of rock mass, mechanical parameters of rock mass and geometric dimensions of tunnel.

Optionally, the three-dimensional numerical calculation network model includes a plurality of model units, wherein, within the range of one time the diameter of the simulated tunnel in the three-dimensional numerical calculation network model, the equivalent size of each of the model units is less than or equal to 1/2 of the equivalent diameter of the tunnel, the size of the outer boundary of the three-dimensional numerical calculation network model is greater than 6 times the equivalent diameter of the tunnel.

Optionally, the step of "analyzing the stress characteristics of surrounding rock in the tunnel face area according to the computer simulation results of the construction process of tunnel excavation and support, and determining the stress distribution parameters of the surrounding rock in the tunnel face area" include:

According to the computer simulation results of the construction process of tunnel excavation and support, the stress characteristics of surrounding rock in the tunnel face area are analyzed, and the stress concentration position of the surrounding rock in the tunnel face area is determined;

Cross-sectional views of different angles and directions at the stress concentration position of the tunnel face area;

According to the sectional view, the spatial position and stress value of the stress concentration in the tunnel face region are determined.

Optionally, the hole depth of the stress relief blasting hole is H, the depth of the rock mass at the spatial position where the stress is concentrated to be blasted is S, and H≧S.

Optionally, three stress relief blasting holes are provided, the three stress relief blasting holes are not arranged collinearly, and the central axes of the three stress relief blasting holes are parallel to each other.

Optionally, the distances between any two of the stress relief blast holes are equal.

Optionally, the step of "arranging explosives in the directional energy gathering ring for directional blasting" includes:

Arranging explosives in the directional energy gathering ring;

blocking the opening of the directional energy gathering ring;

Detonate from a safe distance for directional blasting.

In the technical solution of the present invention, the directional energy-gathering ring includes a ring body, and the outer side surface of the ring body is partially recessed to form an energy-gathering groove extending along its length direction, and the energy-gathering grooves are provided in a plurality of It is arranged at intervals in the circumferential direction, the ring body has an energy release area located between two adjacent energy gathering grooves, each of the energy release areas is provided with a plurality of through holes, and the plurality of through holes are arranged along the The length directions of the ring bodies are arranged in sequence. When stress relief of the surrounding rock of the tunnel is carried out, stress relief blasting holes are first drilled in the high stress concentration area of the surrounding rock, and then the directional energy gathering ring is arranged in the stress relief blasting hole, and then explosives are arranged in the directional energy gathering ring. The opening of the directional energy gathering ring is blocked, and finally blasting is carried out at a safe distance to relieve the stress of the surrounding rock of the tunnel. During blasting, blasting energy is released from the through hole to realize the blasting of the stress relief blasting hole, and the blasting energy is easy to damage the ring body from the energy gathering groove, thereby releasing energy. The energy released by the through holes and the plurality of the energy-gathering grooves forms a mesh-like cut on the stress relief blasting holes, so that the stress relief blasting holes are uniformly destroyed, and the stress in the high stress concentration area of the surrounding rock of the tunnel is better released, effectively preventing The occurrence of rockburst ensures the safety of construction personnel and equipment and the construction progress as planned.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

1 is a schematic three-dimensional structure diagram of an embodiment of a directional energy gathering ring provided by the present invention;

2 is a schematic flowchart of an embodiment of a tunnel surrounding rock stress relief blasting method provided by the present invention;

3 is a schematic structural diagram of a tunnel stress relief blasting hole provided by the present invention;

Fig. 4 is the sectional view at A place in Fig. 3;

FIG. 5 is a schematic structural diagram of a three-dimensional numerical computing network model provided by the present invention.

Description of reference numbers:

label name label name 1 Oriented concentrating ring 112a through hole 11 Ring body 2 stress relief blast hole 111 Energy gathering tank 3 3D Numerical Computing Network Model 112 energy release area 31 model unit

The realization, functional characteristics and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a 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 those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that if there are directional indications (such as up, down, left, right, front, back, etc.) involved in the embodiments of the present invention, the directional indications are only used to explain a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly.

In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for the purpose of description, and should not be construed as indicating or implying Its relative importance or implicitly indicates the number of technical features indicated. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In addition, the meaning of "and/or" in the whole text includes three parallel schemes. Taking "A and/or B" as an example, it includes scheme A, scheme B, or scheme satisfying both of A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of such technical solutions does not exist. , is not within the scope of protection required by the present invention.

Rockburst is a severe dynamic damage phenomenon that occurs in the surrounding rock during the excavation of deep underground caverns or deep mining in the fields of water conservancy and hydropower engineering, transportation, and mining. And with the sudden release of the strain energy of the compressed rock, it is often a dynamic phenomenon in the form of rock fragment ejection, massive rock collapse or mine shock, which can cause serious damage to the excavation face, equipment damage and casualties. The construction progress will also cause problems such as over-excavation and initial support failure. At present, the prevention method of tunnel rock burst is to place explosives after drilling the surrounding rock of the tunnel for blasting. However, blasting directly in the surrounding rock hole, the energy is too concentrated, and the damage degree of the surrounding rock hole is uneven, which leads to the rock formation of the surrounding rock of the tunnel. The explosion prevention effect is poor.

In view of this, the present invention proposes a directional energy gathering ring. When blasting, the blasting energy is released from the through hole to realize the blasting of the stress relief blasting hole, and the blasting energy is easy to destroy the blasting energy from the energy gathering groove. ring body, and then release energy. In this way, the energy released by the plurality of through holes and the plurality of energy gathering grooves forms a mesh cut for the stress relief blasting holes, so that the stress relief blasting holes are uniformly destroyed for better release. The stress in the high stress concentration area of the surrounding rock of the tunnel can effectively prevent the occurrence of rock bursts, ensure the safety of construction personnel and equipment, and the construction progress as planned. As shown in FIG. 1, it is an embodiment of the directional energy gathering ring provided by the present invention.

As shown in FIG. 1 , the directional energy-gathering ring 1 proposed by the present invention includes a ring body 11 , and an energy-gathering groove 111 extending along the length direction of the ring body 11 is partially recessed on the outer surface of the ring body 11 . A plurality of grooves 111 are provided and are arranged at intervals along the circumferential direction thereof. The ring body 11 has an energy release area 112 located between two adjacent energy collecting grooves 111 , and each energy release area 112 is provided with A plurality of through holes 112 a are arranged in sequence along the length direction of the ring body 11 .

In the technical solution of the present invention, the directional energy-gathering ring 1 includes a ring body 11 , and an energy-gathering groove 111 extending along the length direction of the ring body 11 is partially recessed on the outer surface of the ring body 11 , and the energy-gathering groove 111 is provided with The ring body 11 has an energy release area 112 between two adjacent energy collecting grooves 111 , and each of the energy release areas 112 is provided with a plurality of channels. The holes 112 a, the plurality of through holes 112 a are arranged in sequence along the length direction of the ring body 11 . When the stress of the surrounding rock of the tunnel is relieved, the stress relief blasting hole 2 is first drilled in the high stress concentration area of the surrounding rock, and then the directional energy gathering ring 1 is set in the stress relief blasting hole 2, and then the directional energy gathering ring is placed in the directional energy gathering ring. Explosives are set in 1 and the opening of the directional energy gathering ring 1 is blocked, and finally blasting is carried out at a safe distance to relieve the stress of the surrounding rock of the tunnel. During blasting, blasting energy is released from the through hole 112a to achieve the blasting of the stress relief blasting hole 2, and the blasting energy easily destroys the ring body 11 from the energy gathering groove 111, thereby releasing energy, so, The energy released from the plurality of through holes 112a and the plurality of the energy gathering grooves 111 forms a mesh cut on the stress relief blasting holes 2, so that the stress relief blasting holes 2 are uniformly destroyed, and the surrounding rock height of the tunnel is better released. The stress in the stress concentration area can effectively prevent the occurrence of rock bursts, ensure the safety of construction personnel and equipment, and the construction progress as planned.

An embodiment of the present invention provides a blasting method for stress relief of tunnel surrounding rock. Referring to FIG. 2, FIG. 2 is a schematic flowchart of an embodiment of the stress relief blasting method for tunnel surrounding rock provided by the present invention, and FIG. 3 is a tunnel stress relief method provided by the present invention. Schematic diagram of the structure of releasing the blasting hole; FIG. 4 is a schematic diagram of the structure of the three-dimensional numerical calculation network model provided by the present invention.

The present invention also proposes a stress relief blasting method for tunnel surrounding rock, comprising the following steps:

Step S1, determining the stress distribution parameters of the surrounding rock in the tunnel face region, wherein the stress distribution parameters include the spatial position of the stress concentration and the stress value;

Step S2, determining the spatial position of the stress concentration greater than the preset stress value as the spatial position of the stress concentration to be blasted;

Step S3, drilling a stress relief blasting hole 2 at the spatial position where the stress to be blasted is concentrated;

Step S4, correspondingly setting a directional energy gathering ring 1 in the stress relief blasting hole 2, wherein the directional energy gathering ring 1 is set as the directional energy gathering ring 1 as described above;

Step S5, setting explosives in the directional energy gathering ring 1 to perform directional blasting.

In order to prevent rock bursts from occurring in the tunnel after tunnel excavation, threatening the safety of construction personnel and equipment and affecting the construction progress, it is necessary to relieve the stress of the surrounding rock of the tunnel and carry out tunnel rock burst prevention. After the tunnel is excavated, the stress distribution parameters of the surrounding rock in the tunnel face area are first determined, then the determined stress distribution parameters of the surrounding rock in the tunnel face area are compared with the preset stress values, and the tunnel surrounding The spatial position of the stress concentration in the rock that is greater than the preset stress value is set as the spatial position of the stress concentration to be blasted, and then the stress relief blasting hole 2 is drilled at the spatial position of the stress concentration to be blasted, and corresponding to the stress relief blasting hole 2 The directional energy gathering ring 1 is arranged in the blasting hole 2 , and finally explosives are arranged in the directional energy gathering ring 1 for directional blasting. In this way, the stress in the high stress concentration area of the surrounding rock of the tunnel is removed by directional blasting, which can effectively prevent the occurrence of rock bursts, ensure the safety of construction personnel and equipment, and ensure that the construction progress is carried out as planned. It should be noted that the preset stress value is set according to the requirements of construction safety.

Further, in this embodiment, step S1 includes:

Step S11, obtaining the engineering geological parameters of the energy-dissipating tunnel section of the surrounding rock of the tunnel;

Step S12, establishing a three-dimensional numerical calculation network model 3 for simulating the tunnel excavation process;

Step S13, in the three-dimensional numerical calculation software, the three-dimensional numerical calculation network model 3 is processed and set with engineering geological parameters as constraints, so as to simulate the construction process of tunnel excavation and support;

Step S14, according to the computer simulation results of the construction process of tunnel excavation and support, analyze the surrounding rock stress characteristics of the tunnel face area, and determine the stress distribution parameters of the surrounding rock in the tunnel face area.

After the tunnel is excavated, according to the rock mass type of the surrounding rock of the tunnel, the engineering geological parameters of the energy-dissipating tunnel section of the surrounding rock of the tunnel are determined, that is, the relevant engineering geological parameters of the surrounding rock in the tunnel face area are determined, and then in the three-dimensional numerical calculation software , the three-dimensional numerical calculation network model 3 is processed and set with engineering geological parameters as constraints, and then the construction process of tunnel excavation and support is simulated, and according to the computer simulation results of the construction process of tunnel excavation and support, The stress characteristics of the surrounding rock in the tunnel face area are analyzed, and the stress distribution parameters of the surrounding rock in the tunnel face area are finally determined. It should be noted that, in the process of determining the stress distribution parameters of the surrounding rock in the tunnel face region in the present invention, the three-dimensional numerical calculation software used is LS-DYNA, and other rock mass engineering analysis software can also be used according to actual needs.

Specifically, in this embodiment, the engineering geological parameters include the initial in-situ stress of the rock mass, mechanical parameters of the rock mass, and the geometric size of the tunnel. According to the rock mass type of the tunnel construction site, determine the rock mass mechanical properties, rock mass mechanical parameters and rock mass initial in-situ stress. According to the tunnel design scheme, determine the tunnel geometry, size, and construction scheme of tunnel excavation and support, and input the initial in-situ stress of rock mass, mechanical parameters of rock mass, and tunnel geometric size data into three-dimensional numerical calculation software. In the three-dimensional numerical calculation software, the three-dimensional numerical calculation network model 3 is processed with the initial in-situ stress of the rock mass, the mechanical parameters of the rock mass and the geometric size of the tunnel as constraints, and then the construction process of tunnel excavation and support is simulated. By inputting the initial in-situ stress data of the rock mass, the three-dimensional numerical calculation network model 3 simulates the stress of the tunnel rock mass before construction. In this way, through the three-dimensional numerical calculation network model 3 model, the actual construction conditions of tunnel excavation and support are highly restored. , and then obtain more accurate stress distribution parameters of the surrounding rock in the tunnel face area, accurately determine the spatial location of stress concentration in the tunnel face area, and improve the effect of tunnel stress relief.

In order to ensure the accuracy of the tunnel surrounding rock stress distribution parameters obtained by the three-dimensional numerical calculation network model 3, the size parameters of the three-dimensional numerical calculation network model 3 are limited. In this embodiment, the three-dimensional numerical calculation network model 3 includes a plurality of model units 31, wherein, within the range of one time the diameter of the simulated tunnel in the three-dimensional numerical calculation network model 3, the The equivalent size is less than or equal to 1/20 of the equivalent diameter of the tunnel, and the size of the outer boundary of the three-dimensional numerical calculation network model 3 is greater than or equal to 6 times the equivalent diameter of the tunnel. A plurality of the model units together form the three-dimensional numerical calculation network model 3, and in the three-dimensional numerical calculation network model 3, within the range of one time the diameter of the simulated tunnel, that is, the opening of the simulated tunnel is smaller than or equal to the range of the hole diameter. The equivalent size of a single model unit inside is less than or equal to 1/20 of the equivalent diameter of the tunnel, and the size of the outer boundary of the three-dimensional numerical calculation network model 3 is greater than or equal to 6 times the equivalent diameter of the tunnel. By limiting the size of the model unit within the range of one time of the tunnel diameter of the simulated tunnel in the three-dimensional numerical calculation network model 3, and the size of the outer boundary of the three-dimensional numerical calculation network model 3, to ensure the final obtained tunnel tunnel The accuracy of the stress distribution parameters of the surrounding rock in the face area can be accurately determined, and the spatial position of the stress concentration in the tunnel face area can be accurately determined to improve the effect of stress relief of the tunnel.

Further, in this embodiment, step S14 includes:

Step S141, according to the computer simulation result of the construction process of tunnel excavation and support, analyze the surrounding rock stress characteristics of the tunnel face area, and determine the stress concentration position of the surrounding rock in the tunnel face area;

Step S142, intercepting cross-sectional views at different angles and directions at the stress concentration positions in the tunnel face region;

Step S143 , according to the cross-sectional view, determine the spatial position and the stress value of the stress concentration in the tunnel face region.

After the simulation of the construction process of tunnel excavation and support is completed, the stress characteristics of the surrounding rock in the tunnel face area are analyzed according to the simulation results, and then the stress concentration position of the surrounding rock in the tunnel face area is determined. Cross-sectional views of different angles and different directions at the location of the regional stress concentration, and then according to the cross-sectional view, determine the spatial position and stress value of the stress concentration in the tunnel face area, and determine the tunnel according to the spatial position and stress value of the stress concentration. The spatial position and value of the maximum stress concentration in the tunnel face region, thus, the spatial position of the maximum stress concentration in the tunnel face region is the spatial position of the stress concentration to be blasted.

Specifically, in this embodiment, the hole depth of the stress relief blasting hole 2 is H, and the depth of the rock mass at the spatial position where the stress to be blasted is concentrated is S, where H≧S. The hole depth H of the stress relief blasting hole 2 is set to be greater than or equal to the rock mass depth S at the spatial position where the stress to be blasted is concentrated, so that the stress contacts the blasting hole and penetrates the tunnel face area where the stress concentration to be blasted is concentrated. The rock formation in the spatial position to improve the effect of blasting stress relief.

Specifically, in this embodiment, three stress relief blasting holes 2 are provided, the three stress relief blasting holes 2 are not arranged in a collinear line, and the central axes of the three stress relief blasting holes 2 are parallel to each other. By arranging three non-collinear said stress relief blasting holes 2 in the space where the stress concentration to be blasted is concentrated in the tunnel face area, the space position where the stress concentration to be blasted has enough said stress relief blasting holes 2 to ensure The rock formation in the space where the stress concentration to be blasted is effectively blasted, and the effect of blasting stress relief is improved.

More specifically, in this embodiment, the distances between any two of the stress relief blasting holes 2 are equal. By making the distances between any two of the stress relief blasting holes 2 equal, the three stress relief blasting holes 2 are connected to form an equilateral triangle, so as to ensure the effective blasting of the rock formation in the space where the stress concentration to be blasted is concentrated.

Further, in this embodiment, step S5 includes:

Step S51, setting explosives in the directional energy gathering ring 1;

Step S52, blocking the opening of the directional energy gathering ring 1;

Step S53: Detonate at a safe distance to perform directional blasting.

During blasting, an explosive is set in the directional energy gathering ring 1, and an electric detonator for detonating the explosive is placed, and then the opening of the directional energy gathering ring 1 is blocked, and the blasting is initiated outside the safety distance specified in the blasting regulations to carry out directional blasting, In order to relieve the stress in the high stress concentration area of the surrounding rock of the tunnel.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Under the inventive concept of the present invention, any equivalent structural transformations made by the contents of the description and drawings of the present invention, or direct/indirect application Other related technical fields are included in the scope of patent protection of the present invention.

Claims (10)

1. The directional energy gathering ring is characterized by comprising a ring body, wherein energy gathering grooves extending along the length direction of the ring body are formed in the partial concave mode of the outer side surface of the ring body, the energy gathering grooves are arranged in a plurality of mode and are arranged along the circumferential direction of the ring body at intervals, the ring body is provided with an energy releasing area located between every two adjacent energy gathering grooves, each energy releasing area is provided with a plurality of through holes, and the through holes are sequentially arranged along the length direction of the ring body.

2. A tunnel surrounding rock stress relief blasting method is characterized by comprising the following steps:

determining stress distribution parameters of surrounding rocks in a tunnel face area of a tunnel, wherein the stress distribution parameters comprise stress concentration spatial positions and stress values;

determining the spatial position of the stress concentration larger than the preset stress value as the spatial position of the stress concentration to be blasted;

drilling a stress relief blast hole at the spatial position where the stress to be blasted is concentrated;

arranging a directional energy gathering ring in the stress relief blast hole correspondingly, wherein the directional energy gathering ring is arranged as the directional energy gathering ring in claim 1;

and arranging explosives in the directional energy gathering ring for directional blasting.

3. The method for stress relief blasting of surrounding rocks of a tunnel according to claim 2, wherein the step of determining the stress distribution parameters of the surrounding rocks of the tunnel face area comprises:

acquiring engineering geological parameters of a tunnel surrounding rock simulated blasting energy dissipation tunnel section;

establishing a three-dimensional numerical calculation network model for simulating the tunnel excavation process;

in three-dimensional numerical calculation software, processing and setting the three-dimensional numerical calculation network model by taking engineering geological parameters as constraint conditions so as to simulate the construction process of tunnel excavation and support;

according to the computer simulation result of the tunnel excavation and supporting construction process, analyzing the surrounding rock stress characteristics of the tunnel face area, and determining the stress distribution parameters of the surrounding rock of the tunnel face area.

4. A tunnel surrounding rock stress relief blasting method according to claim 3, wherein the engineering geological parameters include initial earth stress of rock mass, rock mechanics parameters and tunnel geometry.

5. The stress relief blasting method for tunnel surrounding rock according to claim 3, wherein the three-dimensional numerical computation network model comprises a plurality of model units, wherein the equivalent size of each model unit is less than or equal to 1/20 of the equivalent diameter of the tunnel within a range of one-time hole diameter of a simulated tunnel in the three-dimensional numerical computation network model, and the size of the outer boundary of the three-dimensional numerical computation network model is greater than 6 times of the equivalent diameter of the tunnel.

6. The method for stress relief blasting of surrounding rocks of a tunnel according to claim 3, wherein the step of analyzing the stress characteristics of the surrounding rocks in the tunnel face area and determining the stress distribution parameters of the surrounding rocks in the tunnel face area according to the computer simulation results of the construction process of tunnel excavation and support comprises:

analyzing the stress characteristics of surrounding rocks in a tunnel face area according to the computer simulation results of the tunnel excavation and support construction process, and determining the stress concentration position of the surrounding rocks in the tunnel face area;

intercepting cross-sectional views of different angles and directions at the stress concentration position of the tunnel face area;

and determining the spatial position of stress concentration and a stress value of the tunnel face area according to the section.

7. The stress relief blasting method for tunnel surrounding rock according to claim 2, wherein the hole depth of the stress relief blasting hole is H, the rock mass depth of the spatial position where the blasting stress concentrates is S, and H is not less than S.

8. The stress-relief blasting method for tunnel wall rock according to claim 2, wherein there are three stress-relief blastholes, three of the stress-relief blastholes are arranged non-collinearly, and central axes of the three stress-relief blastholes are parallel to each other.

9. The method of stress-relief blasting of tunnel wall rock according to claim 8, wherein the distance between any two of said stress-relief blastholes is equal.

10. The method for stress-relief blasting of tunnel surrounding rock according to claim 2, wherein the step of arranging explosives in the directional energy-gathering ring for directional blasting comprises:

arranging an explosive in the directional energy gathering ring;

plugging the opening of the directional energy gathering ring;

and (4) detonating outside the safe distance to perform directional blasting.

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