Roadway / tunneling construction method based on rock drilling and blasting construction method

Abstract

The invention discloses a roadway / tunneling construction method based on a rock drilling and blasting construction method, which comprises the following steps of: using roadway / tunneling construction equipment to excavate and advance in a rock mass of an operation tunnel face along the excavation advancing direction of the operation tunnel face; at least one core-reserved annular free face drill hole for drilling the blasting rock free face and a plurality of blasting rock drill holes are formed in a parallel operation mode; on the basis of drilling of the core-reserved annular free face, drilling, blasting and reaming are carried out, and blasting and reaming are carried out; rock slag is taken out from a cave formed by blasting and reaming; explosive and a segmented delay detonator are filled in the blasting rock drilling hole, and full-section one-time blasting operation is carried out; and rock slag on the working tunnel face is transferred, and anchor rod supporting is conducted on the surrounding rock of the roadway / tunnel. According to the method, the defects caused by outward throwing of rock slag in a conventional rock drilling and blasting construction method are overcome, the defects of an existing technology for eliminating the outward throwing of the rock slag in the conventional rock drilling and blasting construction method do not exist, the construction operation efficiency is improved, the construction speed is increased, and the labor intensity is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of roadway / tunnel excavation construction methods, and particularly to a roadway / tunnel excavation construction method based on the drill and blast rock method. Background Art

[0002] For the roadway (hereinafter referred to as rock roadway) arranged in rock mass in the coal mine system and the tunnel (hereinafter referred to as rock tunnel) arranged in rock mass in the railway, highway, hydropower and other systems, drill and blast rock has always been the most commonly used rock breaking method. Other rock breaking methods include the full-section mechanical blade splitting, rolling and scraping rock breaking of TBM (the English initials abbreviation of tunnel boring machine, including open type and shield type), and the partial-section pick cutting rock breaking of high-power cantilever horizontal axis hard rock tunneling machine.

[0003] In terms of the adaptability to factors such as the pitching angle and excavation and propulsion direction change of the roadway and tunnel (hereinafter referred to as roadway / tunnel) arranged in rock stratum, the cross-section size and the length of the roadway / tunnel, the rock hardness, and the change of surrounding rock stability, drill and blast rock is significantly superior to TBM. In addition, TBM has a large volume, a complex structure, a relatively high cost, a long installation and removal cycle, and significantly higher rock breaking energy consumption per unit volume and engineering cost per meter. Therefore, even though TBM has been available for many years, it still cannot completely replace the traditional drill and blast rock method.

[0004] The cantilever horizontal axis high-power hard rock tunneling machine that has been available for more than twenty years has problems such as high noise and extremely high dust concentration during the pick cutting of hard rock, which seriously endanger the occupational health of construction workers, and high engineering cost per meter (mainly due to high pick consumption, high equipment maintenance, equipment depreciation and financial expenses). If the rock hardness is greater than the Prandtl hardness coefficient of 7, the construction speed will be significantly reduced. Especially after the rock hardness is greater than the Prandtl hardness coefficient of 9, it is almost infeasible to use the hard rock tunneling machine to break rock. Therefore, it has not been widely promoted and applied in roadway / tunnel excavation construction. In very few urban subway tunnel construction projects, due to limited conditions, neither the conventional drill and blast rock method can be used, nor the conditions for using TBM construction are available, so the high-power cantilever horizontal axis hard rock tunneling machine has to be used, and the effect is very unsatisfactory.

[0005] It is entirely predictable that drilling and blasting for rock fragmentation remains an irreplaceable rock fragmentation method at present and for a considerable period in the future. However, as is well known in the industry, during the tunneling construction of the existing drilling and blasting rock fragmentation method, it is necessary to first carry out inclined hole drilling and blasting rock cut in the rock mass of the working face to create a free face (also known as a free surface) for subsequent large-area straight hole drilling and blasting rock fragmentation. Even if all the explosives in the full-section boreholes are detonated at once, the rock fragmentation process is still segmented under the control of delay detonators. First, the explosives in the inclined cut holes are detonated to complete the drilling and blasting cut, and then the explosives in other straight holes are detonated in sequence. However, along with the drilling and blasting cut, a certain amount of high-energy fragmented rock will inevitably be thrown outside tens of meters behind the working face. The throwing of fragmented rock has brought three prominent problems that have been criticized by the industry but have not been overcome by efficient and feasible technologies so far: First, since the thrown fragmented rock will cause serious impact damage to the construction equipment, pipelines, air ducts, etc. within the affected range, it is necessary to withdraw all the construction equipment, pipelines, air ducts, etc. within the affected range before the blasting operation, or take necessary protective measures, and then restore the construction equipment, pipelines, air ducts, etc. to their previous state after the blasting operation. These workloads are additional workloads that will reduce the construction speed. Second, the distribution area of the thrown fragmented rock is relatively wide, and collecting the thrown fragmented rock is also time-consuming, laborious, and will also reduce the construction speed. Third, the thrown fragmented rock is very likely to cause non-negligible impact damage to the bolts, wire mesh, etc. in the area where concrete spraying has not been carried out yet, and may even cause the bolts to fail. Therefore, it is necessary to carry out concrete spraying and covering on the roadway / tunnel after bolt support before the blasting operation. The production process must be "one-step drilling and blasting for rock fragmentation → one-step bolt and mesh support → one-step concrete spraying". Correspondingly, the range of the roadway / tunnel covered by each concrete spraying is only one rock fragmentation step. For small-section roadways / tunnels, due to the serious imbalance between the time occupied by the concrete wet spraying machine and pipeline flushing and the concrete spraying workload, the concrete wet spraying, which is significantly superior to the concrete dry spraying in technology, has not been widely applied in the construction of small-section roadways / tunnels.

[0006] Currently, there are related technologies to eliminate the external throwing of rock slag by the conventional drilling and blasting method and a series of drawbacks brought by it. Specifically: First, several ordinary drilling and blasting holes are created in the rock mass of the working face. Then, a larger drill bit is used to ream the ordinary drilling and blasting holes to serve as the subsequent free face for drilling and blasting. Then, a small-scale drilling and blasting without external throwing of rock slag is carried out based on the free face of drilling and blasting, thus completing the drilling and blasting cut engineering volume in the conventional drilling and blasting. During the process of reaming the conventional drilling and blasting holes for the second time, it takes a lot of time and affects the construction speed. More importantly, in order to meet the requirements of the hole diameter after reaming the conventional drilling and blasting holes, the capacity and size of the rock drilling rig are significantly larger than those of the rock drilling rig used to create the conventional drilling and blasting holes. This is bound to increase the angle between the drilling and blasting holes arranged around the roadway / tunnel and the center line of the roadway / tunnel, which will surely increase the deviation of the roadway / tunnel shape after blasting, and further increase the consumption of engineering materials per meter and the project cost per meter.

[0007] In summary, it is very necessary to research relevant technologies that are targeted and effective in construction technology and techniques, and use more advanced and efficient construction techniques and engineering methods to eliminate the drawbacks brought by the external throwing of rock slag in the conventional drilling and blasting method, and replace the existing technologies for eliminating the external throwing of rock slag in the conventional drilling and blasting method, so as to promote the progress of the roadway / tunnel / heading construction technology based on the drilling and blasting method. Summary of the Invention

[0008] In view of this, the present invention provides a roadway / tunnel heading construction method based on the drilling and blasting method to eliminate the drawbacks brought by the external throwing of rock slag in the conventional drilling and blasting method, reduce the labor intensity, and improve the construction operation efficiency and construction speed.

[0009] To solve the above technical problems, the technical solution adopted by the present invention is: A roadway / tunnel heading construction method based on the drilling and blasting method includes the following steps:

[0010] Step 1, using a roadway / tunnel heading construction equipment, along the excavation and propulsion direction of the working face in the rock mass of the working face, at least one core-retaining annular free face drilling hole serving as the free face for drilling and blasting and multiple drilling and blasting holes are created in a parallel operation manner. The roadway / tunnel heading construction equipment is provided with a rock drilling hole device and a mechanical cutting device. The mechanical cutting device is used to create the core-retaining annular free face drilling hole, and the rock drilling hole device is used to create the drilling and blasting holes;

[0011] Step 2, based on the core-retaining annular free face drilling hole created in Step 1, in the rock mass of the working face along the excavation and propulsion direction of the working face, use the rock drilling hole device to create multiple drilling and blasting reaming holes for expanding the space formed by the core-retaining annular free face drilling hole created in Step 1;

[0012] Step 3: Load explosives and detonators into the drill-and-blast hole enlarged and reamed in Step 2 and detonate them to complete the blasting and hole enlargement.

[0013] Step 4: Remove the rock slag from the cavity formed by the blasting and hole enlargement; alternatively, use the rock drilling device to supplement and create the drill-and-blast rock hole along the excavation and advancement direction of the working face in the working face body, and remove the rock slag from the cavity formed by the blasting and hole enlargement.

[0014] Step 5: Load explosives and sectional delay detonators into the drill-and-blast rock holes distributed in the rock mass of the working face and conduct a one-time full-face blasting operation.

[0015] Step 6: Transport the rock slag of the working face, and after at least completing the bolt support for the roadway / tunnel surrounding rock, return to Step 1 until the roadway / tunnel excavation construction operation ends.

[0016] Among them, the mechanical cut-off device is equipped with a hollow ring-shaped drill bit, and the mechanical cut-off device drives the hollow ring-shaped drill bit to create the core-retaining ring-shaped free face hole in the rock mass of the working face.

[0017] Among them, the depth of the core-retaining ring-shaped free face hole is greater than or equal to one drill-and-blast rock step distance.

[0018] Among them, the depth of the drill-and-blast hole enlarged and reamed and the depth of the drill-and-blast rock hole are not less than one drill-and-blast rock step distance.

[0019] Among them, the number of the core-retaining ring-shaped free face holes is two or more, and the core-retaining ring-shaped free face holes are arranged in a vertically arranged manner.

[0020] After adopting the above technical solution, the present invention has achieved the following beneficial technical effects:

[0021] First of all, the present invention uses a mechanical cut-off device to drive a large-diameter non-core ring-shaped drill bit to create a large-aperture small ring surface with continuously distributed free faces in the rock mass of the working face, and uses a small number of core-retaining ring-shaped free face holes as the free faces for drill-and-blast rock. Supplementary non-external-throw slag drill-and-blast rock is used to moderately and necessarily drill and blast and ream the space formed by the core-retaining ring-shaped free face holes, that is, the engineering quantity of inclined hole drill-and-blast cut-off in the conventional drill-and-blast rock method is completed, meeting the requirements for the free face space for subsequent full-face non-external-throw rock slag drill-and-blast rock of the working face. Thereby, a new drill-and-blast method with the above technical means, operation content and operation steps as the main technical connotations is created; the new drill-and-blast method can efficiently eliminate the inevitable external throwing of drill-and-blast cut-off rock slag and a series of disadvantages brought by it in the existing conventional drill-and-blast rock method, and realizes a substantial technical upgrade of the existing conventional drill-and-blast method.

[0022] Secondly, compared with using a conventional small-diameter solid drill bit to create several small-diameter coreless free face drill holes distributed in the rock mass of the working face to achieve the purpose that the rock mass surrounded by several small-diameter coreless free face drill holes can be efficiently broken by drill blasting, the operation efficiency of creating large-diameter core-retaining annular free face drill holes by the technology of the present invention is higher; compared with using a conventional large-diameter solid drill bit to create large-diameter coreless free face drill holes, the technology of the present invention uses a coreless annular drill bit to create large-diameter core-retaining annular free face drill holes, which not only takes less time, but also can significantly reduce the volume of the mechanical cutters, and is particularly suitable for operating in the engineering environment of small-span tunnels with narrow spaces.

[0023] Thirdly, the creation of the core-retaining annular free face drill holes in the present invention is completed in a parallel operation mode during the process of creating drill blasting holes, which significantly shortens the operation time compared with completing the creation of drill blasting holes and free face drill holes in a relay operation mode, and also saves the time for alternating between the two production processes.

[0024] Fourthly, at least two core-retaining annular free face drill holes are created in the rock mass of the working face. On the one hand, through the one-time reaming of two or more core-retaining annular free face drill holes, the need for the free face space for the subsequent one-time explosion rock breaking of the full section of the working face can be met. On the other hand, the annular area of each core-retaining annular free face drill hole will be smaller than that of creating only one core-retaining annular free face drill hole. Therefore, the volume of the mechanical cutters for creating the core-retaining annular free face drill holes will be correspondingly reduced, which is very necessary for the tunneling construction equipment to adapt to the engineering environment of small-span tunnels with narrow spaces.

[0025] Fifthly, multiple core-retaining annular free face drill holes are arranged in an up-and-down arrangement. Therefore, during the process of creating free face drill holes in the rock mass of the working face, the tunneling construction equipment does not need to horizontally move its crawler chassis. Only by raising the mechanical cutters through the lifting mechanism or raising the chassis of the tunneling construction equipment can the requirements for creating multiple core-retaining annular free face drill holes in the rock mass of the working face be met. This will surely greatly improve the operation efficiency of creating free face drill holes and can significantly reduce the impact on the operation of creating drill blasting holes.

[0026] Sixthly, the biggest advantage of the present invention compared with the aforementioned technology of creating a drill blast cut free face without external thrown rock slag by reaming ordinary drill blasting holes is that the present invention will never increase the angle between the drill blasting holes arranged around the tunnel and the tunnel center line due to increasing the drilling rig capacity and volume for creating drill blasting holes, thus increasing the deviation of the tunnel shape after blasting, and further increasing the consumption of engineering materials per meter and the project cost per meter.

[0027] In summary, the present invention has substantially upgraded the existing drilling and blasting method with feasible technologies. It changes from simply relying on drilling and blasting cut to create the free face space for rock blasting to first creating a core-retaining annular free face borehole as the free face space for rock blasting in the rock mass of the working face by driving a coreless annular drill bit for mechanical cutting, and then supplemented by non-outward-thrown rock slag drilling and blasting to moderately and necessarily expand and brush the space formed by the core-retaining annular free face borehole, thus completing the engineering quantity of inclined hole drilling and blasting cut in the conventional drilling and blasting method and meeting the requirement of the free face space for non-outward-thrown rock slag drilling and blasting of the full section of the subsequent working face; replacing the drilling and blasting cut in the existing conventional drilling and blasting method and the technology of realizing non-outward-thrown rock slag drilling and blasting by expanding and brushing the drilling and blasting boreholes, it can effectively eliminate the rock slag outward throw and a series of drawbacks brought by it that are inevitable in the conventional drilling and blasting method, and there are no obvious deficiencies in the aforementioned non-outward-thrown rock slag drilling and blasting technology. Therefore, it is a substantial technical upgrade of the existing drilling and blasting method, which can improve the mechanization level, construction speed and operation efficiency of roadway / tunnel excavation construction and reduce the labor intensity; since the same construction equipment is used to complete the creation of the free face borehole and the drilling and blasting borehole, and the creation of the free face borehole is completed in a parallel operation manner during the process of creating the drilling and blasting borehole, it also helps to improve the construction speed and operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1-1 FIG. is a schematic diagram of the operating state of the roadway / tunnel excavation construction equipment in the embodiment of the roadway / tunnel excavation construction method based on the drilling and blasting method of the present invention;

[0029] Figure 1-2 is Figure 1-1 side view of;

[0030] Figure 1-3 is Figure 1-1 top view of;

[0031] Figure 2 FIG. is a reference diagram of the working state after implementing Step 1 in the embodiment of the roadway / tunnel excavation construction method based on the drilling and blasting method of the present invention;

[0032] Figure 3 FIG. is a reference diagram of the working state after implementing Step 2 in the embodiment of the roadway / tunnel excavation construction method based on the drilling and blasting method of the present invention;

[0033] Figure 4 FIG. is a reference diagram of the working state after implementing Step 3 in the embodiment of the roadway / tunnel excavation construction method based on the drilling and blasting method of the present invention;

[0034] Figure 5 FIG. is a reference diagram of the working state after supplementing and creating more drilling and blasting boreholes in Step 4 in the embodiment of the roadway / tunnel excavation construction method based on the drilling and blasting method of the present invention;

[0035] Figure 6 It is a reference diagram of the working state after the rock slag is taken out from the cave formed by blasting and enlarging the hole in Step 4 of the embodiment of the roadway / tunnel excavation construction method based on the drill and blast rock excavation method of the present invention;

[0036] Figure 7 It is a reference diagram of the working state after Step 5 of the embodiment of the roadway / tunnel excavation construction method based on the drill and blast rock excavation method of the present invention;

[0037] Figure 8 It is a reference diagram of the working state after Step 6 of the embodiment of the roadway / tunnel excavation construction method based on the drill and blast rock excavation method of the present invention;

[0038] In the figure:

[0039] 1. Roadway / tunnel excavation construction equipment; 11. Rock drilling and boring device; 12. Mechanical cut-off device; 121. Hollow ring bit;

[0040] 2. Anchor bolt;

[0041] A. Rock mass of the working face; A1. Working face; A11. Drill and blast rock boring; A12. Core-retaining ring-shaped free face boring; A13. Core-retaining; A14. Drill and blast expansion and brushing boring; A15. Rock slag; A16. Rock slag. Detailed implementation method

[0042] The technical solution of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments to further understand the purpose, solution and efficacy of the present invention, but it is not intended to limit the scope of protection of the appended claims of the present invention.

[0043] A roadway / tunnel excavation construction method based on the drill and blast rock excavation method includes the following steps:

[0044] Step 1, as shown in Figure 1-1 、 Figure 1-2 and Figure 1-3 , using a roadway / tunnel excavation construction equipment 1, along the excavation and advancement direction of the working face A1 in the rock mass A of the working face, at least one core-retaining ring-shaped free face boring A12 as the free face for drill and blast rock excavation and multiple drill and blast rock borings A11 are created in a parallel operation mode. The roadway / tunnel excavation construction equipment 1 is provided with a rock drilling and boring device 11 and a mechanical cut-off device 12. The mechanical cut-off device 12 is used to create the core-retaining ring-shaped free face boring A12, and the rock drilling and boring device 11 is used to create the drill and blast rock boring A11. The rock drilling and boring device 11 uses a rock drilling rig as the drilling power, and the mechanical cut-off device 12 uses a non-impact power head as the drilling power. The mechanical cut-off device 12 is equipped with a hollow ring bit 121, and the mechanical cut-off device 12 drives the hollow ring bit 121 to create the core-retaining ring-shaped free face boring A12 in the rock mass A of the working face.

[0045] As Figure 2 and Figure 3 shown, in this embodiment, the number of the core - retaining annular free - face drill holes A12 is two, and the two core - retaining annular free - face drill holes A12 are arranged in an up - and - down arrangement. Of course, the number of the core - retaining annular free - face drill holes A12 can also be one or more than two.

[0046] Step 2: As Figure 3 shown, based on the core - retaining annular free - face drill holes A12 created in Step 1, using the rock - drilling and blasting device 11, in the rock mass A of the working face, along the excavation and propulsion direction of the working face A11, create the drill - blasting and enlarging drill holes A14 for enlarging the space formed by the core - retaining annular free - face drill holes A12. The drill - blasting and enlarging drill holes A14 surround the outer periphery of the core - retaining annular free - face drill holes A12 and / or are arranged on the core A13 of the core - retaining annular free - face drill holes A1.

[0047] Step 3: As Figure 4 shown, load explosives and detonators into the drill - blasting and enlarging drill holes A14 created in Step 2 and detonate them to complete the blasting and hole - enlarging.

[0048] Step 4: Take out the rock slag A15 from the cave formed by the blasting and hole - enlarging; or, as Figure 5 and Figure 6 shown, use the rock - drilling and blasting device 11 to supplement and create the drill - blasting rock drill holes A11 in the rock mass A of the working face along the excavation and propulsion direction of the working face A1, and take out the rock slag A15 from the cave formed by the blasting and hole - enlarging.

[0049] Step 5: As Figure 7 shown, load explosives and sectional delay detonators into the drill - blasting rock drill holes A11 distributed in the rock mass A of the working face A1, and implement a one - time full - face blasting operation.

[0050] Step 6: As Figure 8 shown, transport the rock slag A16 of the working face A1. After at least completing the bolt support for the roadway / tunnel surrounding rock, transfer to Step 1 until the roadway / tunnel excavation construction operation ends. Figure 8 The bolt 2 is shown.

[0051] In this embodiment, the depth of the core - retaining annular free - face drill holes A12 is greater than or equal to one drill - blasting rock step distance, and the depths of the drill - blasting and enlarging drill holes A14 and the drill - blasting rock drill holes 11 are not less than one drill - blasting rock step distance.

[0052] The contributions of the present invention to the prior art are mainly reflected in the following two points:

[0053] First of all, in the present invention, a mechanical cutting device drives a large-diameter coreless annular drill bit in the rock mass of the working face, creating a core-retaining annular free face borehole as the free face for drill blasting rock, and supplemented by moderately and necessarily drilling and blasting to expand and brush the space formed by the core-retaining annular free face borehole without external rock slag throwing, thus completing the engineering quantity of inclined hole drill blasting rock cutting in the conventional drill blasting rock method, meeting the requirements of the free face space for the subsequent full-section drill blasting rock without external rock slag throwing on the working face, replacing the drill blasting cutting in the existing conventional drill blasting method, and thereby innovating a new drill blasting method with the above technical means, operation content, and operation steps as the main technical connotations; replacing the inclined hole drill blasting rock cutting in the conventional drill blasting rock method with the new drill blasting method, with engineering-feasible technology, effectively eliminating the external throwing of drill blasting rock slag in the conventional drill blasting rock method and a series of disadvantages brought by it, and having no obvious deficiencies of the aforementioned drill blasting rock technology without external rock slag throwing, realizing a substantial technical upgrade of the existing drill blasting method.

[0054] Secondly, the present invention clearly and in detail describes the basic functions, construction methods and steps of the equipment used in the new drill blasting method, as well as the beneficial technical effects obtained. Promoting and applying the new drill blasting method in roadway / tunnel excavation construction, especially in small-span roadway / tunnel excavation construction, will achieve remarkable economic and social benefits.

[0055] The above is an example of the preferred embodiment of the present invention. The parts not described in detail are all known technologies in the art. The protection scope of the present invention shall be subject to the content of the claims, and any equivalent transformation based on the technical inspiration of the present invention shall be within the protection scope of the present invention.

Claims

1. A roadway / tunnel excavation construction method based on drilling and blasting rock construction method, comprising the following steps: Step 1, using a roadway / tunnel excavation construction equipment, in the working face rock body along the working face excavation advancement direction, to create at least one core-retaining annular free-surface borehole as a drilling and blasting rock free-surface and multiple drilling and blasting rock boreholes in a parallel operation mode, the roadway / tunnel excavation construction equipment is provided with a rock drilling device and a mechanical grooving device, the mechanical grooving device is used to create the core-retaining annular free-surface borehole, and the rock drilling device is used to create the drilling and blasting rock borehole; Step 2, based on the core-retaining annular free-surface drill hole formed in step 1, in the rock mass of the working face along the excavation advancement direction of the working face, using the rock drilling device to create a drill-blasting and brush-expanding drill hole for expanding the space formed by the core-retaining annular free-surface drill hole formed in step 1; Step 3, loading explosives and detonators into the drill-blast-expand brush borehole created in step 2 and detonating them to complete the blast-expanding borehole; Step 4, removing the rock slag from the cave formed by the blasting hole expansion; or, using the rock drilling device in the working face body along the excavation advancement direction of the working face, supplementing the drilling blasting rock hole, and removing the rock slag from the cave formed by the blasting hole expansion; Step 5, loading explosives and segmented time-delay detonators into the drilled and blasted rock holes distributed in the rock mass of the working face, and performing a one-time blasting operation on the entire cross section of the working face; Step 6, after transporting the rock debris of the working face and completing at least the anchor support of the surrounding rock of the lane / tunnel, go to step 1 until the lane / tunnel excavation construction work is completed.

2. The roadway / tunnel excavation construction method based on drilling and blasting rock construction method according to claim 1, characterized in that: The mechanical slotting device is equipped with a hollow annular drill bit, and the mechanical slotting device drives the hollow annular drill bit to form the core-retaining annular free-surface drill hole in the rock mass of the working face.

3. The roadway / tunnel excavation construction method based on drilling and blasting rock construction method according to claim 1, characterized in that: The core-retaining annular free-surface drilling depth is greater than or equal to one drilling and blasting rock step.

4. The roadway / tunnel excavation construction method based on drilling and blasting rock construction method according to claim 1, characterized in that: The drilling depth of the drilling and blasting expansion brush and the drilling depth of the drilling and blasting rock are not less than one drilling and blasting rock step.

5. The roadway / tunnel excavation construction method based on drilling and blasting rock construction method according to claim 1, characterized in that: The number of the core-retaining annular free-surface drilled holes is two or more, and the two or more core-retaining annular free-surface drilled holes are arranged in an upper-lower arrangement.

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