CN116971785A - Method for arranging blastholes according to drilling parameters of tunnel rock drill - Google Patents

Abstract

The invention discloses a method for arranging blast holes according to drilling parameters of a tunnel rock drill, and relates to the technical field of blasting engineering. The method includes: while drilling the tunnel face with a rock drill, collect and record the blast holes at certain time intervals. The parameters while drilling for the 10cm section of the bottom of all cut holes and auxiliary holes for the footage; then determine the soft and hard characteristics of the rock at the location of the drill hole based on the collected parameters while drilling for the footage, and at the same time determine the bottom of the hole for the footage The weakest area Wn of the rock; when drilling the next footage, arrange the center point of the cutout area for this footage at the center point of the softest area Wn of the rock, and then arrange the cutout holes, auxiliary holes and surrounding areas hole. The present invention takes into account the difference in softness and hardness of rocks within the blasting range when drilling tunnel face and arranging blastholes, thereby effectively avoiding waste of explosives or poor blasting results.

Description

A method of arranging blast holes according to drilling parameters of tunnel rock drills

Technical field

The invention relates to the technical field of blasting engineering, and in particular to a method of arranging blast holes according to drilling parameters of a tunnel rock drill.

Background technique

Tunnel construction is an important engineering project in the construction of railways, highways, etc. Currently, the commonly used methods for tunnel excavation at home and abroad include drill and blast method, shield method and boring machine method. Among them, the most widely used method is drill and blast method.

The drill and blast method is a method of excavating rocks through drilling, charging, and blasting. This method has evolved from the early use of manual drills and hammers to drill holes, to the current use of multi-arm drill pipes on rock drilling rigs. to drill holes. Among them, there are still many problems that need to be improved in the drilling and blasthole layout of the tunnel face.

During the construction process of the traditional drill and blast method, the drilling and blast hole layout of the tunnel face are generally carried out from one end to the other according to the construction plan. As the tunnel continues to be excavation, the blasting is not taken into account. The differences and changes in the softness and hardness of rocks within the range often result in a waste of explosives and even poor blasting effects, affecting the quality and progress of tunnel excavation projects.

Even if the drilling and blasthole layout are adjusted based on the blasting results of the existing footage, rough adjustments are usually made based on the engineering experience of the blasting engineers, which cannot effectively improve the blasting results in a reasonable and refined manner. .

Therefore, in drilling and blasting tunneling, in order to avoid the waste of explosives and improve the blasting effect, it is necessary to design a method that can carry out rational and refined drilling and blasthole layout according to the parameters of the tunnel rock drill while drilling. blasthole method.

Contents of the invention

In view of the above problems, in order to overcome the shortcomings of the existing technology and related products, the purpose of the present invention is to propose a method of arranging blast holes according to the drilling parameters of the tunnel rock drill, by adjusting the drilling and drilling parameters according to the drilling parameters of the tunnel rock drill. The blasthole layout can take into account the difference in softness and hardness of rocks within the blasting range, thus effectively avoiding the waste of explosives or poor blasting results.

In order to achieve the above objects, the present invention adopts the following technical solutions:

The invention provides a method for arranging blast holes according to drilling parameters of a tunnel rock drill, which includes the following steps:

Step 1: Use a rock drill to drill blast holes in sequence at the nth excavation footage of the tunnel: cutout holes, auxiliary holes and peripheral holes. While drilling, collect all cutout holes and auxiliary holes from the rock drill at intervals of time t. The while-drilling parameters from 10cm to the bottom of the hole, and save the while-drilling parameters as an array, and the while-drilling parameter array should include the center coordinates of the bottom section of each drilled hole, the average drill pipe impact pressure, the average drill pipe Advance pressure, average drill pipe rotation pressure, average drilling speed;

Step 2: Determine the softness and hardness of the rock at the bottom of each drilling hole based on the hole bottom drilling parameter array of the n-th cutout hole and auxiliary hole;

Step 3: By comparing the softness and hardness of the bottoms of all cut holes and auxiliary holes in the nth footage, determine the coordinates Wn of the bottom of the blast hole with the softest rock at the bottom of the hole;

Step 4: Complete the nth footage blasting construction operation;

Step 5: Start the drilling operation of the n+1th footage, and arrange the centroid point of the cutout area at the coordinate Wn of the blast hole bottom of the nth footage, and determine the position of the cutout hole around the coordinate Wn;

Step 6: Determine the positions of the auxiliary holes and peripheral holes of the n+1th footage around the cutout area;

Step 7: Repeat steps 1-6 to blast and excavate the tunnel.

Further, step 2 includes:

Step 21: Calculate the energy required by the rock drilling rig to drill unit volume of rock, that is, the drilling specific energy e, through the drilling parameters of the rock drill and the physical and mechanical parameters of the rock drill:

In the formula, e is the energy required to drill unit volume of rock, e _i is the energy consumed by impact, e _t is the energy consumed by thrust, e _n is the energy consumed by rotation, eta is the conversion energy efficiency of 40%-70% , p _i is the average drill pipe impact pressure, Δa is the difference between the front area and the rear area of the impact piston, τ is the impact duration, f is the impact frequency, m is the piston mass, v is the average drilling speed, and A is the drilling speed. Cross-sectional area, p _t is the average drill pipe pushing pressure, a is the cross-sectional area of the thrust piston, n is the drill pipe rotation speed, T is the torque, and T torque is the average drill pipe rotation pressure, drill pipe area and drill pipe radius. product;

Step 22: Calculate the uniaxial compressive strength of rock-saturated rock through the specific work of rock crushing:

In the formula: δ _c ------ rock saturated uniaxial compressive strength;

----- Chiseling ratio;

Step 23: Calculate the rock’s solidity coefficient f,

Further, the torque = average drill pipe rotation pressure * maximum torque of rock drilling rig / maximum drill pipe rotation pressure.

Furthermore, when determining the positions of the auxiliary holes and peripheral holes of the n+1th footage around the cutout area in step 6, the auxiliary holes and peripheral holes have the following layout principles:

(1) The distance between the auxiliary hole and the adjacent blast hole is 0.4~0.8m, the distance between the non-bottom peripheral hole and the adjacent blast hole is 0.5~1.0m, and the distance between the peripheral hole and the contour line is 0.1~0.2m;

(2) The distance between adjacent bottom peripheral holes is 0.4~0.7m. During slag blasting, the distance between the bottom peripheral holes is 0.4m;

The opening of the bottom peripheral hole should be 0.1 to 0.2m higher than the tunnel floor, but the bottom of the hole should be 0.1 to 0.2m lower than the floor. During slag blasting, the depth of the blast hole should be deepened by about 0.2m;

The amount of charge in the bottom peripheral hole is between the cutout hole and the auxiliary hole. The charge height is 0.5 to 0.7 times the hole depth. During slag blasting, 1 to 2 charge rolls are added to each hole.

Compared with the existing technology, the present invention can take into account the softness of the rock within the blasting range by adjusting the drilling and blasthole layout according to the drilling parameters of the tunnel rock drill when drilling the tunnel face and arranging the blastholes. The difference in hardness can effectively avoid the waste of explosives or poor blasting effect.

Description of the drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. Those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts.

Figure 1 is a schematic flow chart of a method for arranging blast holes according to drilling parameters of a tunnel rock drill provided by the present invention;

Figure 2 shows the layout of all blast holes in the nth footage;

Figure 3 shows the layout of the n+1th footage cutting area;

Figure 4 shows the layout of all blast holes in the n+1th footage;

Figure 5 shows the layout of cut holes in grade V surrounding rock. The unit in the picture is m;

Figure 6 shows the layout of cutting holes in grade IV surrounding rock. The unit in the figure is m.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all embodiments. The preferred embodiments of the present invention are shown in the accompanying drawings. The present invention may be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to provide a thorough understanding of the disclosure of the present invention.

Figure 1 shows a schematic flow chart of a method for arranging blastholes according to drilling parameters of a tunnel rock drill according to the present invention:

As shown in Figure 1, the present invention provides a method for arranging blast holes according to the drilling parameters of a tunnel rock drill, which includes the following steps:

S1. Use a rock drill to drill blast holes in sequence at the nth excavation footage of the tunnel: cutout holes, auxiliary holes and peripheral holes. While drilling, collect the data of all cutout holes and auxiliary holes from the rock drill at intervals of time t. Parameters while drilling from 10cm to the bottom of the hole, and save the parameters while drilling as an array. The array of parameters while drilling should include the center coordinates of the bottom section of each drilling hole, the average drill pipe impact pressure, and the average drill pipe advancement. pressure, average drill pipe rotation pressure, average drilling speed.

The blast holes drilled in the tunnel in step 1 are divided into cut holes, auxiliary holes (caving holes) and peripheral holes according to their positions and functions, as shown in Figure 2.

During tunnel excavation and blasting, since there is only one free surface and the surrounding rocks have great clamping force, the blasting conditions are difficult, so the layout of the cutout holes is extremely important. The function of the cutout hole is to first create a groove cavity on the working surface as the second free surface to create favorable conditions for blasting other blastholes. The function of the peripheral holes is to control the specification and shape of the tunnel section. The peripheral holes are also called contour holes. The rocks around the tunnel are blasted, and finally the design outline of the tunnel section is formed. The specification and shape of the tunnel section are controlled to ensure that the tunnel section, shape and direction after blasting comply with the design. Require. The function of the auxiliary holes is to expand and extend the scope of the cut. The auxiliary holes, also called collapse holes, are a large number of parallel or roughly parallel blast holes between the cut holes and the surrounding holes. Sometimes they also include several auxiliary cut holes. To further expand the cavity formed by blasting the cutout hole. The caving hole is the main blast hole for breaking rock. The free surface created by the cutting is used to collapse a large amount of rock.

In the drill-and-blast tunnel excavation project in step 1, a large amount of engineering experience shows that the while-drilling parameters from 10cm from the bottom of the hole to the bottom of the hole in the previous footage have the highest correlation with the characteristics of the surrounding rock of the tunnel in the next footage.

S2. Determine the softness and hardness of the rock at the bottom of each drilling hole based on the hole bottom while drilling parameter array of the n-th cutout hole and auxiliary hole.

Drilling while drilling parameters include average drilling speed, average drill pipe impact pressure, average drill pipe advancement pressure, average drill pipe rotation pressure, average water pressure and average water flow, etc. Through these while drilling parameters and other rock drilling rigs The physical parameters of can calculate the energy consumed in drilling unit volume of rock. Generally speaking, the harder, stronger, and more complete the rock, the more energy it consumes to drill a unit volume of rock.

According to research by domestic scholars, there are three modes of action in the rock-breaking process of rock drill bits: impact, thrust and rotation. Analysis: During the entire drilling and rock breaking process, impact action is the main form of rock breaking, which can produce stress concentration. The thrust action uses axial static load, which can form prestress in the rock and improve the rock crushing effect. In addition, by applying thrust, close contact between the drill bit and the rock can be ensured, which can facilitate the transmission of impact energy. The final rotational effect is the application of hoop rotational speed. The purpose of rotation is to move the position of the drill bit teeth to help cut the rock around the impact blast hole.

Through the drilling parameters of the rock drill while drilling and some other physical and mechanical parameters of the rock drill, the energy required by the rock drilling rig to drill unit volume of rock can be calculated, that is, the drilling specific energy e (MJ/m ³ ).

The formula is:

In the formula, e is the energy required to drill unit volume of rock (MJ/m ³ ), e _i is the energy consumed by impact (e _i , MJ/m ³ ), and e _t is the energy consumed by thrust (e _t , MJ /m ³ ), _en is the energy consumed by rotation ( _en , MJ/m ³ ), eta is the conversion energy efficiency of about 40%-70%, p _i is the impact force (Mpa), Δa is the area in front of the impact piston The difference between the and the rear area (mm ² ), τ is the impact duration (s), f is the impact frequency (Hz), m is the piston mass (kg), v is the drilling speed (m/s), and A is the drilling hole The cross-sectional area (m ² ), p _t is the thrust (Mpa), a is the cross-sectional area of the thrust piston (mm ² ), n is the drill pipe rotation speed (r/min), and T is the torque (N*m). T torque is the product of the average drill pipe rotation pressure, drill pipe area and drill pipe radius. The actual data processing method is also based on the maximum torque of 671N*M and the maximum rotation pressure of 210bar of the rock drilling rig provided by the manufacturer. Therefore, 671/210 is used Proportional calculation of torque at different rotational pressures.

In addition, through experimental research, the mathematical relationship between the uniaxial compressive strength of rock saturated rock and the specific work of chipping of rock has been obtained, such as formula (2): The saturated uniaxial compressive strength of rock is referred to as compressive strength, which is the uniaxial compressive strength of rock under unidirectional compression conditions. Below, the ultimate compressive stress value when the rock specimen is damaged, the specific work of chipping It is the work consumed to break a unit volume of rock.

In the formula: δ _c ------rock saturated uniaxial compressive strength, MPa;

------Specific work of chiseling, J/cm ³ ;

Through experimental research, it was found that for the same kind of rock, the drilling specific energy e (MJ/m ³ ) and the chipping specific work a (J/cm ³ ) are almost equal, that is At the same time, the unit symbol conversion is 1MJ/m ³ =1J/cm ³ .

After calculating the uniaxial compressive strength of the rock, the rock can be divided into 10 levels according to the rock's solidity coefficient (f). The higher the rock's level, the easier it is to break (that is, the lower the rock's solidity coefficient, the softer the rock). Ruggedness coefficient is also called Platts coefficient:

In the formula: f----- rock solidity coefficient, unit 1;

Ruggedness coefficient grading table, as shown in Table 1:

Table 1

S3. By comparing the softness and hardness of the bottom of all cut holes and auxiliary holes in the nth footage, determine the bottom coordinates Wn of the blast hole where the rock at the bottom of the hole is the softest.

S4. Complete the remaining blasting construction operations of the nth footage: charging, detonation, slag removal, etc.

Blasting construction operations include drilling, charging, detonation, cleaning and slag removal, transportation, etc. Therefore, after completing drilling and collecting parameters while drilling in this footage, the remaining blasting construction operations need to be completed.

S5, as shown in Figure 3, start the drilling operation of the n+1th footage, and arrange the centroid point of the cutout area at the bottom coordinate Wn of the blast hole of the nth footage, and determine the cutout hole around the coordinate Wn s position;

The area surrounded by the perimeter of the cut hole of this footage is the cut area, and the center of this area is the centroid point of the cut area.

S6, as shown in Figure 4, determine the position of the auxiliary hole and peripheral hole of the n+1th footage around the cutout area.

The auxiliary holes and peripheral holes have the following layout principles:

(1) The holes should be distributed evenly, which not only makes full use of energy, but also ensures that the rock collapses according to the designed contour line. The spacing depends on the nature of the rock. Generally, the distance between the auxiliary hole and the adjacent blast hole is 0.4~0.8m, the distance between the non-bottom peripheral hole and the adjacent blast hole is 0.5~1.0m, and the distance between the peripheral hole and the contour line is 0.1 ~0.2m.

(2) It is difficult to arrange the holes around the bottom, and blind shots are likely to occur when there is water accumulation. Therefore:

1) The distance between adjacent bottom peripheral holes is 0.4~0.7m. During slag blasting, the distance between the bottom peripheral holes is 0.4m.

2) The opening of the bottom peripheral hole should be 0.1 to 0.2m higher than the tunnel floor, but the bottom of the hole should be 0.1 to 0.2m lower than the floor. During slag blasting, the depth of the blast hole should be deepened by about 0.2m.

3) The amount of charge in the bottom peripheral hole is between the cutout hole and the auxiliary hole. The charge height is 0.5 to 0.7 times the hole depth. During slag blasting, 1 to 2 charge rolls are added to each hole.

S7. Repeat steps S1-S6 to blast and excavate the tunnel.

By utilizing a method of arranging blastholes according to drilling parameters of a tunnel rock drill provided by the present invention to adjust drilling and blasthole layout, the difference in softness and hardness of rocks within the blasting range can be taken into account, thereby effectively avoiding the waste of explosives or blasting. not effectively.

Tunnel blasting engineering examples:

1. Project Overview

Sanqingshan Tunnel is located in Shangrao City, Jiangxi Province, with a total length of 11,861m. The maximum dimension of the tunnel at its highest point is 12.94m, and its maximum width is 14.86m. The tunnel cross-section shape will be constructed in accordance with the design requirements of the railway department. The strata in the tunnel site area are mainly Yanshanian granite, Sinian siltstone, siliceous rock and quartz sandstone. The surrounding rock of the tunnel is good, mainly composed of type IV and V surrounding rocks. The burial depth of the entrance section of the tunnel is about 50-100m, and the rest is 200-500m.

2. Explosion design principles

1. Ensure that the cross-sectional size and contour surface flatness after blasting and excavation meet the design requirements. Over-excavation shall not be greater than 15cm and under-excavation shall not be greater than 5cm.

2. The gravel after blasting and excavation is uniform in size and concentrated in piles, making it easy to load and transport the slag.

3. According to the design requirements and geological conditions, determine reasonable blasting parameters and detonation methods to minimize disturbance to the rock mass around the tunnel.

4. On the premise of ensuring the blasting effect, try to reduce the blast hole length and blasting equipment consumption required for blasting unit rock mass, and reduce blasting costs.

5. Accelerate the progress of project construction while ensuring construction quality.

6. Fully consider the construction environmental protection and civilized construction requirements, and adopt advanced, reasonable, safe, reliable, and economically feasible blasting construction plans to ensure the smooth progress of the project construction.

3. Overall construction plan

The surrounding rock conditions of the tunnel are good, and the tunnel is entered from the entrance and exit respectively. A full-section one-time drilling and blasting excavation plan is adopted, that is, the tunnel is excavated by cutting in the middle, auxiliary holes around it, and smooth blasting around the periphery according to the designed contour.

4. Explosion design

1. Excavation footage is circulated. The surrounding rocks of this tunnel are mainly types IV and V. The cyclic excavation footage of type IV surrounding rock is 3.0m, and the cyclic excavation footage of type V surrounding rock is 3.5m.

2. Explosives cost per unit. The unit consumption of Class IV surrounding rock explosives is about 0.8kg/m ³ and the unit consumption of Class V surrounding rock explosives is about 1.0kg/m ³ .

3. Drilling layout. According to the overall plan of full-section excavation, cut holes are arranged in the middle, auxiliary holes are arranged around, and smooth blasting holes are arranged around the perimeter.

1) Drilling diameter: Use a hand drill to drill the hole. Except for the diameter of the middle hollow hole d1=89mm, the rest are d=42mm. The drilling platform is self-made and is divided into three floors, with 4 drilling rigs on each floor for three-dimensional operation.

2) Cutout hole: The cutout hole is located in the middle and lower part of the tunnel. It adopts a compound wedge-shaped cutout hole with 2 empty holes in the middle and 9 cutout holes on the left and right sides. The row spacing of cutout holes is 0.9m, and the hole spacing is 0.4m. The layout of cutout holes is shown in Figures 1-2.

3) Auxiliary holes: The auxiliary holes are vertical holes. Auxiliary hole spacing: a=(8~12)d=0.70m; blast hole utilization rate eta=90%; hole depth: L=l/90%. The hole depths of type IV and V surrounding rock are 3.3m and 3.8m respectively.

4) Smooth blast holes: In order to facilitate construction and make the excavation section consistent with the designed section, the smooth blast holes are drilled 0.2m away from the excavation contour line and tilted outward at 4°. The smooth blast hole spacing b = (10 ~ 18) d = 0.60m; the smooth blast hole density coefficient m is 0.8, and the minimum resistance line: w = b/m = 0.75 m. The blast hole layout is shown in Figures 5 and 6.

5. Charge structure design

The explosive uses No. 2 rock emulsion explosive. The medicine roll is 20cm long and each section weighs 0.15kg.

1. Packing length: L1=(10~20)d=0.50m.

2. Charge structure:

1) Cutting holes. The length of the blast hole is 1.6~4.1m, the length of the charge from the bottom of the hole is 1.2~3.6m, 6~18 sections of charge rolls are continuously loaded, and the remaining part is filled.

2) Auxiliary holes. For Class IV surrounding rock, the length of the blast hole is 3.3m, the length of the charge from the bottom of the hole: 3.3m--0.5m=2.8m, 14 sections of charge are continuously loaded, and the remaining part is filled; for Class V surrounding rock, the length of the blast hole is It is 3.8m, the charge length is: 3.8m--0.6m=3.2m, 16 sections of charge are continuously loaded, and the remaining part is filled.

3) Light blast holes. For Class IV surrounding rock, the length of the blast hole is 3.3m. For Class V surrounding rock, the length of the blast hole is 3.8m. The linear charge density is 0.20kg/m, and the charges are spaced.

6. Construction according to the method of the present invention

Step 1: Use a rock drill to drill blast holes in sequence at the nth excavation footage of the tunnel: cutout holes, auxiliary holes and peripheral holes. While drilling, collect all cutout holes and auxiliary holes from the rock drill at intervals of time t. The while-drilling parameters of the 10cm section at the bottom of the hole are saved as an array, and the while-drilling parameter array should include the center coordinates of the bottom section of each drill hole, the average drill pipe impact pressure, the average drill pipe advancement pressure, the average Drill pipe rotation pressure and average drilling speed.

Step 2: Determine the softness and hardness of the rock at the bottom of each drilling hole based on the hole bottom while drilling parameter array of the n-th cutout hole and auxiliary hole.

Through the parameters while drilling and the mechanical performance parameters of the rock drilling rig, the energy required to drill a unit volume of rock in each hole is calculated, that is, the drilling and crushing specific energy. The hardness and softness of the rock are divided through this parameter.

Step 3: By comparing the softness and hardness of the bottoms of all cut holes and auxiliary holes in the nth footage, determine the coordinates Wn of the bottom of the blast hole with the softest rock at the bottom of the hole;

Step 4: Complete the remaining blasting construction operations of the nth footage: charging, detonation, slag removal, etc.

Step 5: Start the drilling operation of the n+1th footage, and arrange the centroid point of the cutout area at the coordinate Wn of the blast hole bottom of the nth footage, and determine the position of the cutout hole around the coordinate Wn;

Step 6: Determine the position of the auxiliary hole and peripheral hole of the n+1th footage around the cutout area.

Step 7: Repeat steps 1-6 to blast and excavate the tunnel.

Contents not described in detail in this specification belong to the prior art known to those skilled in the art. The above are only embodiments of the present invention, but do not limit the patent scope of the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still implement the foregoing specific Modify the technical solution recorded in the method, or make equivalent replacements for some of the technical features. Any equivalent modifications made using the contents of the description and drawings of the present invention and applied directly or indirectly in other related technical fields shall likewise fall within the scope of patent protection of the present invention.

Claims (4)

1. A method for arranging blastholes according to drilling parameters of a tunnel rock drill, which is characterized by including the following steps: Step 1: Use a rock drill to drill blast holes in sequence at the nth excavation footage of the tunnel: cutout holes, auxiliary holes and peripheral holes. While drilling, collect all cutout holes and auxiliary holes from the rock drill at intervals of time t. The while-drilling parameters from 10cm to the bottom of the hole, and save the while-drilling parameters as an array, and the while-drilling parameter array should include the center coordinates of the bottom section of each drilled hole, the average drill pipe impact pressure, the average drill pipe Advance pressure, average drill pipe rotation pressure, average drilling speed; Step 2: Determine the softness and hardness of the rock at the bottom of each drilling hole based on the hole bottom drilling parameter array of the n-th cutout hole and auxiliary hole; Step 3: By comparing the softness and hardness of the bottoms of all cut holes and auxiliary holes in the nth footage, determine the coordinates Wn of the bottom of the blast hole with the softest rock at the bottom of the hole; Step 4: Complete the nth footage blasting construction operation; Step 5: Start the drilling operation of the n+1th footage, and arrange the centroid point of the cutout area at the coordinate Wn of the blast hole bottom of the nth footage, and determine the position of the cutout hole around the coordinate Wn; Step 6: Determine the positions of the auxiliary holes and peripheral holes of the n+1th footage around the cutout area; Step 7: Repeat steps 1-6 to blast and excavate the tunnel. 2. The method according to claim 1, characterized in that step 2 includes: Step 21: Calculate the energy required by the rock drilling rig to drill unit volume of rock, that is, the drilling specific energy e, through the drilling parameters of the rock drill and the physical and mechanical parameters of the rock drill: In the formula, e is the energy required to drill unit volume of rock, e _i is the energy consumed by impact, e _t is the energy consumed by thrust, e _n is the energy consumed by rotation, eta is the conversion energy efficiency of 40%-70% , p _i is the average drill pipe impact pressure, Δa is the difference between the front area and the rear area of the impact piston, τ is the impact duration, f is the impact frequency, m is the piston mass, v is the average drilling speed, and A is the drilling speed. Cross-sectional area, p _t is the average drill pipe pushing pressure, a is the cross-sectional area of the thrust piston, n is the drill pipe rotation speed, T is the torque, and T torque is the average drill pipe rotation pressure, drill pipe area and drill pipe radius. product; Step 22: Calculate the uniaxial compressive strength of rock-saturated rock through the specific work of rock crushing: In the formula: δ _c ------ rock saturated uniaxial compressive strength; ------ Chiseling ratio; Step 23: Calculate the rock’s solidity coefficient f, 3. The method according to claim 2, characterized in that the torque=average drill pipe rotation pressure*maximum torque of rock drilling rig/maximum drill pipe rotation pressure. 4. The method according to claim 1, characterized in that, when determining the position of the auxiliary hole and the peripheral hole of the n+1th footage around the recessing area in step 6, the auxiliary hole and the peripheral hole have the following arrangement principles: (1) The distance between the auxiliary hole and the adjacent blast hole is 0.4~0.8m, the distance between the non-bottom peripheral hole and the adjacent blast hole is 0.5~1.0m, and the distance between the peripheral hole and the contour line is 0.1~0.2m; (2) The distance between adjacent bottom peripheral holes is 0.4~0.7m. During slag blasting, the distance between the bottom peripheral holes is 0.4m; The opening of the bottom peripheral hole should be 0.1 to 0.2m higher than the tunnel floor, but the bottom of the hole should be 0.1 to 0.2m lower than the floor. During slag blasting, the depth of the blast hole should be deepened by about 0.2m; The amount of charge in the bottom peripheral hole is between the cutout hole and the auxiliary hole. The charge height is 0.5 to 0.7 times the hole depth. During slag blasting, 1 to 2 charge rolls are added to each hole.