Construction method for TBM construction tunnel to penetrate through strong rockburst section rock mass

Abstract

The invention discloses a construction method for a TBM construction tunnel to penetrate through a strong rockburst section rock mass, and belongs to the technical field of tunnel engineering rockburst prevention construction processes. According to the construction method for the TBM construction tunnel to penetrate through the rock mass of the strong rockburst section, the construction rockburst strength of the strong rockburst section can be effectively reduced, and the construction safety is improved. According to the construction method, a tunnel penetrating through a strong rockburst section rock mass is formed by excavating section by section in a sectional tunneling mode, and in the construction process of each section of tunnel, a tunnel face formed in the excavation process of a previous section of tunnel is used as a foundation; a circle of broken zone ring layer is at least formed in the rock mass on the periphery of the arch crown, the arch shoulder and the arch waist part of the next section of tunnel through the tunnel face, and the stress in the strong rockburst rock mass of the section is released in advance through the broken zone ring layer; and the rock burst high-risk area of the section of the strong rock burst rock mass is transferred to the rock mass away from the tunnel to reduce the probability of rock burst in TBM construction, and then the section of TBM construction penetrating through the strong rock burst rock mass tunnel is conducted.

Description

Technical Field

[0001] The invention relates to a construction method, in particular to a construction method for a TBM to construct a tunnel through a rock mass in a strong rock burst area, and belongs to the technical field of rock burst prevention construction technology for tunnel engineering. Background Art

[0002] During the TBM construction of tunnels, strong rock burst areas are a very challenging problem. Rock burst is a series of dynamic instability geological disasters caused by the sudden release of stored elastic strain energy in hard and brittle surrounding rocks due to excavation unloading during underground engineering excavation under high ground stress conditions, such as bursting, loosening, spalling, ejection and even throwing damage. During the TBM construction process, when encountering strong rock burst areas, it not only causes serious damage to construction equipment and threatens the lives of construction workers, but also greatly delays the construction progress and increases project costs. Construction is often forced to stop, seriously affecting the progress and safety of the project.

[0003] Traditional coping methods include strengthening support, reducing excavation speed, etc., which are often used to remedy rock bursts after they occur. However, these methods often cannot fundamentally prevent rock bursts, have limited effects and are costly. Specifically, the existing technology has the following shortcomings when dealing with strong rock burst areas during tunnel TBM construction:

[0004] 1. Most of the cases are handled after the fact, and there is a lack of effective preventive measures beforehand, which cannot solve the rock burst problem from the root.

[0005] 2. Conventional support methods are difficult to effectively cope with the huge energy release and rock mass damage caused by strong rock bursts.

[0006] 3. The inability to actively change the stress state of the surrounding rock makes the risk of rock bursts remain high.

[0007] 4. If a rock burst occurs, it often occurs in the surrounding rock of the tunnel, which can easily cause equipment damage and casualties.

[0008] At present, there are relatively few studies on the treatment methods for strong rockburst areas, and it is difficult to effectively prevent the occurrence of rockbursts. Therefore, a technical method is needed to pre-treat strong rockburst areas before construction to prevent the occurrence of rockbursts, improve construction safety, and ensure construction progress. Summary of the invention

[0009] The technical problem to be solved by the present invention is to provide a construction method for TBM construction tunnel passing through rock mass in strong rock burst sections, which can effectively reduce the rock burst intensity during construction in strong rock burst sections and improve construction safety.

[0010] The technical solution adopted to solve the above technical problems is: a construction method for a TBM tunnel to pass through a rock mass in a strong rock burst section, wherein the construction method adopts a segmented excavation method to excavate a tunnel passing through the rock mass in the strong rock burst section section by section, and in the excavation process of each section of the tunnel, the tunnel face formed in the excavation process of the previous section of the tunnel is used as a basis, and a circle of broken belt ring layers are formed in the rock mass around the arch crown, arch shoulder and arch waist of at least the next section of the tunnel through the tunnel face, and the stress in the strong rock burst rock mass of this section is released in advance through the broken belt ring layer, so that the high-risk area of ​​rock burst in this section of the strong rock burst rock mass is transferred to the rock mass far away from the tunnel, thereby reducing the probability of rock burst during TBM construction, and then the TBM construction of this section of the tunnel passing through the strong rock burst rock mass is carried out, and so on until the construction of all tunnels passing through the rock mass in the strong rock burst section is completed.

[0011] Furthermore, when a fractured zone is formed in the rock mass outside the tunnel vault, spandrel and waist, high-energy blasting, conventional blasting, hydraulic fracturing or mechanical fracturing is used.

[0012] The preferred embodiment of the above scheme is that when high-energy blasting is used to form a broken zone ring layer in the rock mass outside the vault, spandrel and waist of the tunnel by drilling, the following steps are followed: first, based on the existing face, at least three high-explosive holes extending into the rock mass along the length direction are drilled through the face into the rock mass outside the vault, spandrel and waist of the next tunnel respectively, and then shaped explosives are filled at the bottom of each high-explosive hole and sealed by grouting, and then the shaped explosives at the bottom of each high-explosive hole are detonated to form a broken zone ring layer in the rock mass outside the vault, spandrel and waist of the next tunnel along the length direction of the tunnel.

[0013] Furthermore, when drilling high-explosive holes in the rock mass outside the arch crown, arch shoulder and arch waist of the next section of the tunnel, a one-hole-multiple-holes method is adopted, and the bottoms of each hole in the one-hole-multiple-holes in the same part are located in the same horizontal plane.

[0014] A preferred embodiment of the above scheme is that the bottoms of the holes formed by the multiple holes at the crown, spandrel and waist are grouped in the same cross section along the tunnel length direction.

[0015] Furthermore, the vertical distance d between the bottom of each hole and the corresponding wall of the tunnel is not less than 5m, and the horizontal distance between the bottom of the circle of holes adjacent to the tunnel face and the tunnel face is not less than 3m.

[0016] A preferred embodiment of the above scheme is that the shaped charge is a long strip of charge covered with an outer shell, and a large opening and a small opening extending along the length direction are arranged on the outer shell of the long strip of charge at intervals along the circumference, and the hole size of the large opening is not less than twice the hole size of the small opening.

[0017] Furthermore, at least two pre-cut slits are arranged at the bottom of each hole, and the pre-cut slits are all located on the same straight line. When detonating the shaped explosives at the bottom of each high-explosive hole, they are detonated simultaneously or from the inside to the outside along the length of the tunnel.

[0018] The preferred method of the above scheme is to evaluate the effect of the pretreatment after the blasting is completed, monitor the crushing condition of the broken zone ring layer and the connectivity of the broken zone, and immediately reinforce the broken and unbroken parts with long anchor rods after the tunnel is formed.

[0019] Furthermore, during the long anchor reinforcement, the rock mass around the tunnel vault, arch shoulder and arch waist is reinforced with long anchors respectively. The end of the long anchor is located in the rock mass outside the fracture zone. After the anchor reinforcement is completed, a section of tunnel excavation is carried out.

[0020] The beneficial effect of the present invention is that the construction method provided by the technical solution of the present application adopts the mode of segmented excavation and construction for the rock mass in the strong rock burst section, and in the excavation process of each section of the tunnel, the heading face formed in the excavation process of the previous section of the tunnel is used as the basis, and a circle of broken belt layer is formed in the rock mass around the arch crown, arch shoulder and arch waist of at least the next section of the tunnel through the heading face, and the stress in the strong rock burst rock mass of this section is released in advance through the broken belt layer, so that the high-risk area of ​​rock burst in this section of the strong rock burst rock mass is transferred to the rock mass far away from the tunnel, thereby reducing the probability of rock burst during TBM construction, and then the TBM construction of this section of the tunnel passing through the strong rock burst rock mass is carried out, and so on until the construction of all tunnels passing through the rock mass in the strong rock burst section is completed. In this way, before TBM excavation construction, the strong rock burst rock mass outside the tunnel is first crushed to form a circle of crushing zone, which improves the stress release. Therefore, when TBM excavation construction is adopted, the rock burst intensity of the strong rock burst section can be effectively reduced, thereby achieving the purpose of improving construction safety and effectively ensuring the construction progress. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A side view of a surrounding rock drilling hole involved in a construction method for a TBM tunnel to pass through a rock mass in a strong rock burst area according to the present invention;

[0022] Figure 2 for Figure 1 A top view of

[0023] Figure 3 for Figure 1 Axonometric view of

[0024] Figure 4 It is a schematic diagram of the structure of the shaped charge involved in the construction method of the present invention for TBM tunnel construction passing through the rock mass in the strong rock burst area;

[0025] Figure 5 This is a rendering of the surrounding rock blasting of the present invention;

[0026] Figure 6 This is a diagram of the fractured zone formed stably by the surrounding rock after blasting in the present invention;

[0027] Figure 7 It is a schematic diagram of excavation after the broken circle layer is formed in the present invention.

[0028] Marked in the figure are: tunnel 1, face 2, broken zone ring 3, high-explosive hole 4, shaped explosive 5, outer shell 6, large opening 7, small opening 8, pre-cut slit 9, long anchor rod 10. DETAILED DESCRIPTION

[0029] Terminology explanation:

[0030] Broken zone ring: The broken rock mass surrounding the contour line of the tunnel face formed by blasting and other means obliquely above the tunnel face achieves the effect of relieving the surrounding rock pressure, thereby preventing the occurrence of rock bursts, and can concentrate the stress of the surrounding rock and transfer it to the deep, so that the rock burst occurs inside the rock and does not affect the TBM construction.

[0031] Focused charge blasting: Using the hole at one end of the explosive charge to enhance the effect of local destruction is called the focused charge effect, which can control the direction and distance of the blast.

[0032] like Figure 1 to Figure 7The present invention provides a construction method for a TBM tunnel through a rock mass in a strong rock burst section, which can effectively reduce the intensity of rock burst during construction in a strong rock burst section and improve construction safety. The construction method adopts a segmented excavation method to excavate a tunnel 1 through a rock mass in a strong rock burst section section by section, and in the excavation process of each section of the tunnel 1, the face 2 formed in the excavation process of the previous section of the tunnel 1 is used as a basis, and a circle of broken belt ring layer 3 is formed in the rock mass around the arch crown, arch shoulder and arch waist of at least the next section of the tunnel through the face 2, and the stress in the rock mass of the strong rock burst section is released in advance through the broken belt ring layer 3, so that the high-risk area of ​​rock burst in the rock mass of the strong rock burst section is transferred to the rock mass far away from the tunnel 1 to reduce the probability of rock burst during TBM construction, and then the TBM construction of the tunnel 1 through the strong rock burst rock mass is carried out, and so on until the construction of all tunnels through the rock mass of the strong rock burst section is completed. The construction method provided by the technical solution of the present application adopts the method of segmented excavation and segmented excavation for the rock mass in the strong rock burst section, and in the process of excavating each section of the tunnel, the face formed in the process of excavating the previous section of the tunnel is used as the basis, and a circle of broken belt layers is formed in the rock mass outside the arch crown, arch shoulder and arch waist of at least the next section of the tunnel through the face, and the stress in the strong rock burst rock mass of this section is released in advance through the broken belt layer, so that the high-risk area of ​​rock burst in this section of the strong rock burst rock mass is transferred to the rock mass far away from the tunnel to reduce the probability of rock burst during TBM construction, and then the TBM construction of this section of the tunnel passing through the strong rock burst rock mass is carried out, and so on until the construction is completed. All tunnels passing through the rock mass in the strong rock burst section are completed. In this way, before the TBM excavation construction is carried out, the strong rock burst rock mass outside the tunnel is first crushed to form a circle of broken belt layers, which improves the release of stress, so that the rock burst intensity of the strong rock burst section can be effectively reduced when the TBM excavation construction is adopted, so as to achieve the purpose of improving construction safety and effectively ensuring the construction progress.

[0033] In combination with the existing technology, when forming a broken zone ring layer in the rock mass outside the tunnel vault, spandrel and waist, the present application can adopt drilling high-energy blasting, drilling conventional blasting, drilling hydraulic crushing, and drilling mechanical crushing. The technical solution provided by the present application preferentially adopts drilling high-energy blasting to form a broken zone ring layer in the rock mass outside the tunnel vault, spandrel and waist.

[0034] Correspondingly, when the present application adopts drilling high-energy blasting to form a broken zone ring layer 3 in the rock mass outside the tunnel vault, spandrel and waist part, it is carried out according to the following steps. First, based on the existing tunnel face 2, at least three high-explosive holes 4 extending into the rock mass along the length direction are drilled through the tunnel face 2 respectively into the rock mass outside the vault, spandrel and waist part of the next tunnel, and then shaped explosives 5 are filled at the bottom of each high-explosive hole 4 and sealed by grouting, and then the shaped explosives 5 at the bottom of each high-explosive hole are detonated, so as to form a circle of broken zone ring layer 3 in the rock mass outside the vault, spandrel and waist part of the next tunnel along the length direction of the tunnel.

[0035] In order to form a broken zone layer 3 in the outer rock mass of the tunnel in the strong rock burst section to the maximum extent, and to improve the coherence of the formed broken zone layer 3, and then to improve the formation quality of the broken zone layer 3, the present application adopts a one-hole-multiple-holes method when drilling high-explosive holes 4 in the rock mass outside the arch crown, arch shoulder and arch waist of the next section of the tunnel, and the bottoms of the holes in the one-hole-multiple-holes in the same part are all located in the same horizontal plane. And the bottoms of the holes formed by the one-hole-multiple-holes in the arch crown, arch shoulder and arch waist are grouped in the same cross section along the length direction of the tunnel. Moreover, when making holes, at least two pre-cut seams 9 are respectively set at the bottom of each hole, and the pre-cut seams 9 are all located on the same straight line. When detonating the shaped explosives 5 at the bottom of each high-explosive hole, the method of simultaneous detonation or detonation from the inside to the outside along the length direction of the tunnel is adopted. At the same time, in order to ensure subsequent excavation construction, the vertical distance d between the bottom of each hole in the present application and the corresponding wall of the tunnel 1 is not less than 5m, and the horizontal distance between the bottom of the circle of holes adjacent to the face 2 and the face 2 is not less than 3m.

[0036] Furthermore, after the blasting is completed, it is necessary to evaluate the effect of the pretreatment, monitor the crushing condition of the broken zone layer 3 and the connectivity of the broken zone, and immediately reinforce the broken and unpaved parts with long anchor rods 10 after the tunnel is formed. When the long anchor rods 10 are reinforced, the rock mass outside the tunnel vault, spandrel and waist is reinforced with long anchor rods 10 respectively, and the end of the long anchor rod 10 is located in the rock mass outside the broken zone layer 3. After the anchor rod reinforcement is completed, another tunnel is excavated.

[0037] Combined with the actual application, the shaped charge 5 of the present application is a long strip of charge covered with an outer shell 6, and a large opening 7 and a small opening 8 extending along the length direction are arranged on the outer shell 6 of the long strip of charge at intervals along the circumferential direction, and the hole size of the large opening 7 is not less than twice the hole size of the small opening 8.

[0038] In summary, the construction technology and method of the TBM tunnel provided in this application passes through the strong rock burst section. On the one hand, the surrounding rock is relieved in advance to prevent the occurrence of rock burst; on the other hand, the intact rock mass between the crushed surface and the surrounding rock forms a circle of support to further prevent the impact of rock burst. At the same time, the stress concentration position of the surrounding rock is transferred to the depth of the surrounding rock. Even if a rock burst occurs, it will occur in the outer layer of the crushed zone, which will not affect the tunnel construction and can also block the transmission of the surrounding rock force. It effectively prevents the occurrence of rock burst, ensures the safety and progress of tunnel construction, and has important engineering application value.

[0039] Specifically, it has the following advantages:

[0040] 1. It realizes active pressure relief and prevention in advance for strong rock burst areas, reducing the possibility of rock burst.

[0041] 2. By forming a fracture zone, the stress concentration of the surrounding rock is transferred to the deep part, so that the high-risk area of ​​rock burst is far away from the tunnel, ensuring the safety of TBM tunnel construction.

[0042] 3. Compared with the traditional post-processing method, the present invention is more proactive and preventive, and can significantly reduce the impact of rock burst on construction, ensure the normal advance of TBM in strong rock burst areas, ensure construction safety and progress, and reduce project costs.

[0043] 4. Compared with traditional countermeasures, the method of the present invention has the advantages of low cost, good effect, and easy operation, and will not affect the normal construction process of TBM.

[0044] 5. This method is also applicable to tunnel construction using the drill and blast method, but the drill and blast method is more flexible and can be adjusted on this basis.

[0045] The technical solution of the present application is further described below through specific embodiments:

[0046] Embodiment 1

[0047] The main contents of the present invention are as follows:

[0048] The present invention provides a construction technology and method for a TBM tunnel to safely pass through a strong rock burst section. By drilling holes obliquely in front of the tunnel face and using methods such as concentrated energy blasting, a circle of broken belt layers is formed outside the contour line of the tunnel face, thereby achieving early pressure relief and support for the surrounding rock and preventing the occurrence of rock bursts.

[0049] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. If no specific conditions are specified in the invention, the invention shall be carried out according to conventional conditions or conditions recommended by on-site technicians. The construction method of the tunnel TBM construction in a strong rock burst section of the present invention comprises the following steps:

[0050] (I) Drilling construction

[0051] According to the geological conditions and design requirements of the tunnel, determine the location and number of holes drilled in the vault, spandrel, waist and other areas prone to strong rock bursts in front of the face. Use appropriate drilling equipment to drill holes to ensure that the diameter and depth of the holes meet the requirements. The bottoms of these holes are located on the same straight line. In order to avoid damage to the surrounding rock of the tunnel due to too many holes, the method of drilling multiple holes is adopted, which is convenient and practical. Among them, the diameter of the hole can be the same as that of the ordinary grouting anchor hole. There are certain requirements for the depth of the hole. Because the blasting impact range is at least 3 to 5 meters, the distance d between the bottom of the hole and the tunnel contour line should be at least 5 meters, and the horizontal distance l between the nearest hole to the face and the face should be at least 3 meters. In addition, in order to facilitate the installation of explosives in the later stage, when the hole reaches the predetermined depth, the bottom of the hole needs to be expanded. In order to save construction steps, the expansion drill bit can be used directly for construction when drilling. It should be noted that in order to ensure the correct direction and ideal effect of the subsequent blasting, it is best to cut two pre-cut slits at the bottom of each hole with a blade after each hole is completed. The specific operation is the same as the pre-cut slit construction method of directional hydraulic fracturing. It is necessary to ensure that the pre-cut slits at the bottom of each hole are located on the same straight line, such as Figures 1 to 3 shown.

[0052] (II) Explosives installation and blocking

[0053] The shaped charge is installed at the bottom of the hole through drilling. In order to ensure the blasting effect, the shell of the shaped charge is preferably designed with a T-shaped opening structure, with larger openings on both sides and a smaller opening in the middle, such as Figure 4 Therefore, during installation, the two sides of the larger opening should be placed horizontally and aligned with the other drilling directions, and the side with the smaller opening should face the deep part of the surrounding rock. After the explosives are installed, the drilling hole needs to be sealed, that is, cement mortar and other cementitious materials are injected into the drilling hole. After solidification, it has a certain strength. It mainly has two functions: one is to ensure the explosion effect, and the other is to ensure construction safety.

[0054] (III) Energy-gathering blasting

[0055] After the blasting device is installed at the bottom of the borehole, the boreholes are blasted and connected by methods such as concentrated energy blasting. Blasting is carried out according to a predetermined blasting sequence to form blasting connections between the boreholes. Figure 5 As shown. It should be noted that it is best to detonate all boreholes at the same time during blasting. If this is not possible, they should be detonated in order from the inside to the outside. In order to ensure the blasting effect, it is necessary to control the blasting parameters, such as the amount of explosives, detonation time, and borehole spacing. The specific parameters should be determined based on the local surrounding rock strength, the bottom spacing of the boreholes, etc., and refer to formulas (1) to (2) to ensure that the surrounding rock crushing meets the predetermined effect, thereby forming a circle of crushing belt outside the contour line of the face, such as Figure 6 It should be noted that one blast does not require that the cracks between adjacent boreholes be completely penetrated, but the cracks should at least be close to each other, forming a structure similar to a "weak beam". In the process of adjusting the surrounding rock stress in the later stage, the "weak beam" has a low bearing capacity and is easily crushed, forming a through crack, which can also achieve the purpose. Of course, it would be best if it can be completely penetrated in one blast.

[0056] Drilling spacing formula:

[0057]

[0058] Where: L is the distance between the boreholes (meters), V is the charge of explosives (kilograms), and k is a coefficient related to geological conditions and blasting purpose, usually between 1.5 and 3.

[0059] Charge amount formula:

[0060]

[0061] Where: M is the charge of each borehole (kg), W is the weight of the rock (kg), which can usually be calculated from the volume and density of the rock, V is the volume of the blasting area (cubic meters), and D is the diameter of the borehole (meters).

[0062] (IV) Effect monitoring and TBM excavation

[0063] After the blasting is completed, it is best not to start construction immediately. Monitor the stress state and deformation of the surrounding rock, evaluate the pretreatment effect, and adjust and optimize the pretreatment measures if necessary based on the monitoring results. After the evaluation is completed, TBM excavation can be carried out. Due to the long-distance pretreatment, the TBM can be advanced for a long distance at a time, all the way to the deepest vertical section of the borehole, to ensure the construction progress. Figure 7 shown.

[0064] (V) Follow-up of support measures

[0065] During the TBM excavation process, support measures should be followed closely. Since the surrounding rock has been crushed to a certain depth, if there are no other changes and considerations, the support measures can be appropriately reduced compared to the original plan, such as increasing the spacing between steel arches, increasing the density of steel mesh, etc., to reduce construction costs. If safety is a concern, the original support plan can also be adopted. Here, one issue needs to be noted. Since the blasting effect cannot be fully controlled, if the blasting cracks extend toward the tunnel contour, growth anchors should be applied locally. The anchors should penetrate deep into the surrounding rock above the crushed zone to ensure the anchoring effect. Figures 6-7 The specific details can be determined by the on-site construction personnel.

[0066] (VI) Circular Excavation

[0067] After completing a TBM advance, steps (i) to (v) can be repeated to ensure that the tunnel passes through the strong rock burst area quickly.

[0068] In summary, the above technical solution provided by the present application has the following significant differences compared with the prior art:

[0069] 1. Drill holes in a specific area obliquely in front of the face and use concentrated energy blasting to form a broken zone layer.

[0070] 2. The formation of the fracture zone ring relieves the pressure on the surrounding rock in advance and prevents the occurrence of rock bursts.

[0071] 3. The formation of the fracture zone causes the stress concentration position of the surrounding rock to shift deeper into the surrounding rock. Even if a rock burst occurs, it will occur in the outer layer of the fracture zone and will not affect the tunnel construction.

[0072] 4. The intact rock mass between the fractured zone and the tunnel is equivalent to a layer of natural support, which blocks the possibility of rock bursts around the tunnel and ensures the safety of tunnel construction.

Claims

1. A construction method for a TBM tunnel through a rock mass in a strong rock burst area, characterized by: The construction method adopts a segmented excavation method to form a tunnel (1) passing through a rock mass in a strong rock burst section by segment, and during the excavation process of each tunnel section (1), the tunnel face (2) formed during the excavation process of the previous tunnel section (1) is used as a basis, and a circle of fractured zone (3) is formed in the rock mass at least outside the arch crown, arch shoulder and arch waist of the next tunnel section through the tunnel face (2), and the stress in the strong rock burst rock mass of the section is released in advance through the fractured zone (3), so that the high-risk rock burst area of ​​the section of the strong rock burst rock mass is transferred to the rock mass far away from the tunnel (1), thereby reducing the probability of rock burst during TBM construction, and then the TBM construction of the section of the tunnel (1) passing through the strong rock burst rock mass is carried out, and so on until the construction of all tunnels passing through the rock mass in the strong rock burst section is completed.

2. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 1, characterized in that: When a broken zone ring is formed in the rock mass outside the tunnel vault, spandrel and waist, high-energy blasting, conventional blasting, hydraulic crushing or mechanical crushing is used.

3. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 2, characterized in that: When high-energy blasting is used to form a crushing zone ring layer (3) in the rock mass outside the arch crown, arch shoulder and arch waist of a tunnel, the following steps are followed: first, based on an existing tunnel face (2), at least three high-explosive holes (4) extending into the rock mass along the length direction are drilled through the tunnel face (2) into the rock mass outside the arch crown, arch shoulder and arch waist of the next tunnel, and then shaped explosives (5) are filled at the bottom of each high-explosive hole (4) and sealed by grouting, and then the shaped explosives (5) at the bottom of each high-explosive hole are detonated, so that a crushing zone ring layer (3) is formed in the rock mass outside the arch crown, arch shoulder and arch waist of the next tunnel along the length direction of the tunnel.

4. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 3, characterized in that: When drilling high-explosive holes (4) in the rock mass outside the arch crown, arch shoulder and arch waist of the next section of the tunnel, a one-hole-multiple-hole method is adopted, and the bottoms of the holes in the one-hole-multiple-holes at the same location are all located in the same horizontal plane.

5. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 4, characterized in that: The bottoms of the holes formed by multiple holes at the crown, spandrel and waist are grouped separately along the length direction of the tunnel and are located in the same section.

6. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 3, 4 or 5, characterized in that: The vertical distance d between the bottom of each hole and the corresponding wall of the tunnel (1) is not less than 5m, and the horizontal distance between the bottom of the circle of holes adjacent to the tunnel face (2) and the tunnel face (2) is not less than 3m.

7. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 6, characterized in that: The shaped charge (5) is a long strip of charge covered with an outer shell (6), and a large opening (7) and a small opening (8) extending in the length direction are arranged on the outer shell (6) of the long strip of charge at intervals along the circumference, and the aperture size of the large opening (7) is not less than twice the aperture size of the small opening (8).

8. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 7, characterized in that: At least two pre-cut slits (9) are respectively arranged at the bottom of each hole, and each pre-cut slit (9) is located on the same straight line. When the shaped explosives (5) at the bottom of each high-explosive hole are detonated, they are detonated simultaneously or from the inside to the outside along the length direction of the tunnel.

9. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 8, characterized in that: After the blasting is completed, the effect of the pretreatment is evaluated, the crushing condition of the crushing zone ring layer (3) and the connectivity of the crushing zone are monitored, and the long anchor rods (10) are immediately used to reinforce the crushed and unreinforced parts after the tunnel is formed.

10. The construction method for a TBM tunnel through a rock mass in a strong rock burst area according to claim 9, characterized in that: When the long anchor rod (10) is used for reinforcement, the long anchor rod (10) is used to reinforce the rock mass around the tunnel vault, the arch shoulder and the arch waist in sequence. The end of the long anchor rod (10) is located in the rock mass outside the fracture zone ring layer (3). After the anchor rod reinforcement is completed, a tunnel excavation is carried out.

Images