A tunnel lining support and tunnel crossing an active fault fracture zone

Abstract

The present invention provides a tunnel lining support and a tunnel that passes through an active fault fracture zone. The tunnel lining support includes an initial support, a waterproof layer, and a secondary lining that are sequentially arranged from the outside to the inside along the tunnel radial direction; the secondary lining includes a segment area, the active fault fracture zone is located in the middle of the segment area in the longitudinal direction of the tunnel, and the segment area includes a plurality of segment secondary linings that are sequentially arranged at intervals along the longitudinal direction of the tunnel, and deformation joints are provided between two adjacent segment secondary linings, and the deformation joints are filled with buffers. The tunnel lining support enables the tunnel to adapt to the displacement and rotation of the fault and improves its own seismic performance.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, in particular to a tunnel lining support and a tunnel passing through an active fault fracture zone. Background Art

[0002] With the rapid development of my country's railway construction, the standards and grades of railway construction are also constantly improving. When the geological conditions in the area where the railway passes are complex and active fault structures are developed, mountain tunnels will inevitably pass through active fault structures due to the restrictions of high-standard and high-grade railway line selection conditions. Active faults are active, and fault dislocation will cause cracking and falling of tunnel lining concrete. In severe cases, collapse and damage to supporting structures may occur, seriously affecting the safety of railway operations. Research on seismic fortification structures and shock absorption measures for tunnels crossing active fault fracture zones has become an urgent problem that construction engineers need to solve.

[0003] At present, there is no mature design method and tunnel seismic structural system when the tunnel passes through active faults. Most of the design measures and concepts adopted at home and abroad include expansion, hinge connection, seismic isolation, etc. Excavation expansion design is to expand the cross-sectional size during tunnel excavation construction according to the displacement of the active fault fracture zone. When the fault is displaced, the expanded cross-section can ensure the clear area of ​​the tunnel cross-section. After the disaster, rapid repair can be achieved by adjusting the line slope and other methods. The amount of expansion is mainly determined by the displacement mode and displacement of the active fault fracture zone. Hinge connection is to divide the overall structure of the tunnel into short tunnel segments, and a flexible connection structure with relatively small stiffness is used between the segments. When the fault is displaced, the damage is concentrated at the connection position or the local structure, and will not cause the overall damage of the structure. Vibration reduction and isolation is composed of initial support, secondary lining and intermediate backfill flexible material isolation layer, which transforms the original lining-surrounding rock system into lining-shock-absorbing layer-surrounding rock system. Its purpose is to separate the lining from the surrounding rock medium through the shock-absorbing layer, thereby reducing and changing the intensity and mode of earthquake action on the structure, so as to achieve the purpose of reducing structural vibration.

[0004] Design measures such as excavation, hinge connection, and vibration reduction and isolation all have certain limitations. Especially when the tunnel passes through a large active fault, the width of the broken zone between the upper and lower plates of the fault is large, and there is uncertainty in the rupture surface when the fault moves. Engineering measures such as tunnel excavation and vibration reduction and isolation for long sections will increase construction costs, increase construction difficulty, and increase construction period. The amount of tunnel excavation is difficult to determine, and filling an isolation layer under the tunnel invert for vibration reduction and isolation may affect the safety of railway operations. Although the hinge connection of the tunnel can better adapt to the shear deformation of fault movement, due to the complex seismic characteristics of the active fault, the hinge connection part is difficult to adapt to the tensile deformation along the longitudinal direction of the tunnel, and often becomes a weak link. The damage of the hinge structure increases the risk of landslides in this area. Summary of the invention

[0005] The first object of the present invention is to provide a tunnel lining support that passes through an active fault fracture zone, wherein the tunnel lining support enables the tunnel to adapt to fault dislocation and rotation and improves its own seismic resistance.

[0006] A second object of the present invention is to provide a tunnel having the above-mentioned tunnel lining support.

[0007] To achieve the above-mentioned first purpose, the present invention provides a tunnel lining support that passes through an active fault fracture zone, including an initial support, a waterproof layer and a secondary lining arranged in sequence from the outside to the inside along the radial direction of the tunnel; the secondary lining includes a segment area, the active fault fracture zone is located in the middle of the segment area in the longitudinal direction of the tunnel, the segment area includes a plurality of segment secondary linings arranged in sequence along the longitudinal direction of the tunnel, and a deformation joint is provided between two adjacent segment secondary linings, and a buffer is filled in the deformation joint.

[0008] It can be seen from the above scheme that the secondary lining structure of the tunnel is divided into multiple segmental secondary linings, making the tunnel a discontinuous segmented structure similar to the structure of the animal spine, and deformation joints are set between adjacent segments, and buffers are filled in the deformation joints to make each tunnel segment relatively independent. When the active fault moves, the displacement in the strong deformation zone near the contact surface between the active fault and the bedrock is mainly concentrated in the deformation joints with weak rigidity. The continuously set deformation joints can effectively share the concentrated displacement at the fault fracture zone, and each tunnel segment moves relatively independently under the action of the lateral deformation soil.

[0009] The tunnel lining support structure that simulates the animal spine and passes through the active fault fracture zone has the ability to adapt to the fault dislocation and rotation by setting a short-segment, wide-joint, high-rigidity circular ring lining structure in the active fault fracture zone and the extension sections on both sides thereof, thereby avoiding large-scale lining structure damage.

[0010] A preferred solution is that a secondary lining reinforcement space is provided on the radial inner side of the tunnel.

[0011] It can be seen that when the tunnel structure is damaged and cracks appear in the active fault fracture zone, the secondary lining reinforcement space can be used to repair the secondary lining structure. By reserving reinforcement space and strengthening the support system, the seismic fortification goal of "technically feasible, economically reasonable, and easy to repair" can be achieved.

[0012] A preferred solution is that the multiple segmented second linings include at least two first segmented second linings and at least four second segmented second linings; the first segmented second linings are located in the middle of the active fault fracture zone, the second segmented second linings are located near the contact surface between the active fault fracture zone and the bedrock, and at least one second segmented second lining is arranged at each end of the active fault fracture zone; the length of the first segmented second lining in the longitudinal direction of the tunnel is greater than the length of the second segmented second lining in the longitudinal direction of the tunnel; the deformation joint between two adjacent first segmented second linings is a first deformation joint; at least two second segmented second linings are arranged at each end of the active fault fracture zone, and the deformation joint between two adjacent second segmented second linings is a second deformation joint; the width of the second deformation joint is greater than the first deformation joint.

[0013] It can be seen that wide deformation joints are mainly set in the strong deformation zone near the contact surface between the active fault fracture zone and the bedrock, and the tunnel segment in this range is the shortest. When the active fault moves, the displacement in the strong deformation zone near the contact surface between the active fault fracture zone and the bedrock is mainly concentrated between the deformation joints with weak rigidity. The continuously set wide deformation joints can effectively share the concentrated displacement at the fault fracture zone, while each tunnel segment moves relatively independently under the action of the lateral deformation soil. In addition, narrow deformation joints are set at positions where the fault displacement is relatively small, mainly in the central position of the core of the active fault fracture zone and the fortification extension range close to the fault surface on the bedrock. At the same time, considering the convenience of tunnel construction, the tunnel segment in this range is relatively long. Each segment tunnel will be like a continuous curved beam when crossing the active fault fracture zone area to withstand the shear and bending of the deformed soil.

[0014] A further solution is that the width of the first deformation joint is in the range of 2 cm to 3 cm, and the width of the second deformation joint is 5 to 8 times the width of the first deformation joint.

[0015] A preferred solution is that the length of the secondary lining of the second section is in the range of 4 meters to 8 meters, and the length of the secondary lining of the first section is 3 times the length of the secondary lining of the second section.

[0016] It can be seen that the research shows that the shorter the tunnel segment and the wider the deformation joint, the smaller the degree and scope of the tunnel structure being damaged by the dislocation of the active fault crushing zone. However, a tunnel segment that is too short brings certain difficulties and inconveniences to the construction, and a deformation joint that is too wide makes it difficult to ensure the tunnel waterproofing and drainage effect. Therefore, the width of the narrow deformation joint is within the range of 2 cm to 3 cm, the wide deformation joint can be determined according to the displacement of the active fault crushing zone, the width of the wide deformation joint is 5 to 8 times the width of the narrow deformation joint, and the length of the tunnel segment should match the length of the secondary lining template. The length of the short segment secondary lining is 4 meters to 8 meters, the length of the longer segment secondary lining is 2 times the length of the short segment secondary lining, and the length of the long segment secondary lining is 3 times the length of the short segment secondary lining. When the length of each segment secondary lining is within the above range, and when each deformation joint is within the above range, it is ensured that the degree and scope of the tunnel structure being damaged by the dislocation of the active fault crushing zone is small, it is easy to construct, and the tunnel waterproofing and drainage effect is effectively guaranteed.

[0017] A preferred solution is that the multiple segment second linings also include multiple third segment second linings, at least two third segment second linings are arranged at each end of the active fault fracture zone, and the third segment second linings are located at the position of the bedrock close to the active fault fracture zone; the length of the third segment second lining is greater than the length of the second segment and less than the length of the first segment.

[0018] A further solution is that the length of the second lining of the third section is twice the length of the second lining of the second section; the deformation joint between two adjacent second linings of the third section is the third deformation joint, and the width of the third deformation joint is in the range of 2 cm to 3 cm.

[0019] A preferred solution is that the multiple segment second linings also include at least two fourth segment second linings, and the fourth segment second linings are located between the first segment second lining and the second segment second lining; at least one fourth segment second lining is arranged at each end of the active fault fracture zone, and the length of the fourth segment second lining is greater than the length of the second segment and less than the length of the first segment; the deformation joint between the fourth segment second lining and the first segment second lining is the fourth deformation joint, and the deformation joint between the second segment second lining and the fourth segment second lining is the fifth deformation joint, and the widths of the fourth deformation joint and the fifth deformation joint are both 5 to 8 times the width of the first deformation joint.

[0020] A preferred solution is that the buffer is a foam plastic board, and the waterproof layer is provided with a pleated expansion shell waterproof board at the deformation joint.

[0021] It can be seen that the buffer made of foam plastic board can provide good support and buffering effect. In addition, by arranging the expansion shell waterproof board with folds at the position of the waterproof layer at the deformation joint, it can effectively prevent the waterproof structure at the deformation joint from being destroyed when the active fault moves.

[0022] To achieve the second objective, the present invention provides a tunnel, including the tunnel lining support for crossing an active fault fracture zone. The tunnel lining support also includes an annular grouting reinforcement ring arranged on the fractured surrounding rock outside the tunnel excavation contour, and the initial support is located radially inward of the grouting reinforcement ring.

[0023] It can be seen that the grouting reinforcement ring can strengthen the integrity of the surrounding rock, improve the surrounding rock conditions to enhance its own anti-dislocation and creep capabilities, thereby improving the seismic resistance of the tunnel lining support structure, and at the same time reduce groundwater leakage at the deformation joints after the active fault dislocation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic cross-sectional view of a tunnel lining support structure in a tunnel embodiment of the present invention.

[0025] Figure 2 yes Figure 1 A partial enlarged view of point A in the middle.

[0026] Figure 3 It is a schematic longitudinal section diagram of a tunnel embodiment of the present invention passing through an active fault fracture zone.

[0027] Figure 4 yes Figure 3 A partial enlarged view of point B in the middle.

[0028] Figure 5 It is a schematic diagram of the twisting and rotation of the tunnel structure of the tunnel embodiment of the present invention after the active fault fracture zone is displaced.

[0029] The present invention is further described below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0030] See also Figure 1 and Figure 2 The tunnel of this embodiment includes a tunnel lining support that passes through an active fault fracture zone 11, and the tunnel lining support includes an initial support 6, a waterproof layer 2, and a secondary lining 3 that are sequentially arranged from the outside to the inside along the tunnel radial direction. The tunnel lining support also includes an annular grouting reinforcement ring 10 that is arranged on the broken surrounding rock outside the tunnel excavation contour, and the initial support 6 is located on the radial inner side of the grouting reinforcement ring 10.

[0031] The active fault shattering zone 11 is provided with defense extension sections 12 at both ends in the longitudinal direction of the tunnel (i.e. the extension direction of the tunnel), and the defense extension sections 12 are located on the bedrock close to the contact surface between the active fault shattering zone 11 and the bedrock (i.e. the fault plane 14).

[0032] The grouting reinforcement ring 10 is formed by grouting the broken surrounding rock outside the tunnel excavation contour through a radially extending steel flower pipe 100 set in a full ring. The initial support 6 includes a full ring steel frame 61 made of HW175 steel and C30 concrete 62 sprayed in the full ring. A waterproof layer 2 is set between the initial support 6 and the secondary lining 3. The secondary lining 3 is formed of C35 reinforced concrete, and the shape of the secondary lining 3 is close to a circular ring. The secondary lining 3 is also provided with a second lining reinforcement space 4 on the radial inner side of the tunnel, and the thickness of the second lining reinforcement space 4 is 25 cm.

[0033] See also Figure 3 and Figure 4 The secondary lining 3 includes a segment area, and the segment area includes a plurality of segment secondary linings arranged in sequence along the longitudinal direction of the tunnel. The plurality of segment secondary linings are respectively three first segment secondary linings 31, thirteen second segment secondary linings 32, four third segment secondary linings 33 and two fourth segment secondary linings 34. A deformation joint is provided between two adjacent segment secondary linings, and a buffer (not shown) is filled in the deformation joint, and the buffer is a foam plastic board. In the longitudinal direction of the tunnel, the two ends of the segment area in the length direction extend from the two ends of the active fault fracture zone 11 to the direction away from the active fault fracture zone 11, that is, the active fault fracture zone 11 is located in the middle of the segment area in the longitudinal direction of the tunnel.

[0034] The three first-segment second linings 31 are all located in the middle of the active fault fracture zone 11. The thirteen second-segment second linings 32 are all located near the fault plane 14. Six second-segment second linings 32 are arranged at the first end of the active fault fracture zone 11, and seven second-segment second linings 32 are arranged at the second end of the active fault fracture zone 11. A fourth-segment second lining 34 is arranged between the first-segment second lining 31 and the second-segment second lining 32 which are closest to each other. In addition, two third-segment second linings 33 are respectively arranged on the defense extension sections 12 at both ends of the active fault fracture zone 11.

[0035] The lengths of the first section secondary lining 31, the fourth section secondary lining 34 and the second section secondary lining 32 in the longitudinal direction of the tunnel decrease successively. The length of the third section secondary lining 33 is greater than the length of the second section secondary lining 32 and less than the length of the first section secondary lining 31, and is equal to or close to the length of the fourth section secondary lining 34. The second section secondary lining 32 is a short section secondary lining and its length is in the range of 4 meters to 8 meters. The third section secondary lining 33 and the fourth section secondary lining 34 are both longer section secondary linings and their lengths are both twice the length of the second section secondary lining 32. The first section secondary lining 31 is a long section secondary lining and its length is three times the length of the second section secondary lining 32.

[0036] The deformation joint between two adjacent first-section second linings 31 is the first deformation joint 51, the deformation joint between the fourth-section second lining 34 and the first-section second lining 31 is the fourth deformation joint 54, the deformation joint between the second-section second lining 32 and the fourth-section second lining 34 is the fifth deformation joint 55, the deformation joint between two adjacent second-section second linings 32 is the second deformation joint 52, the deformation joint between two adjacent third-section second linings 33 is the third deformation joint 53, and the deformation joint between the adjacent third-section second lining 33 and the second-section second lining 32 is the sixth deformation joint 56.

[0037] The fourth deformation seam 54, the fifth deformation seam 55 and the second deformation seam 52 are all wide deformation seams and their widths are greater than the first deformation seam 51. The first deformation seam 51, the third deformation seam 53 and the sixth deformation seam 56 are all narrow deformation seams, the width of the narrow deformation seam is in the range of 2 cm to 3 cm, and the width of the wide deformation seam is 5 to 8 times the width of the narrow deformation seam.

[0038] In addition, the waterproof layer 2 is provided with a pleated expansion shell waterproof board at the deformation joint. By providing the waterproof layer 2 with a pleated expansion shell waterproof board at the position of the deformation joint, it can effectively prevent the waterproof structure at the deformation joint from being destroyed when the active fault moves.

[0039] During tunnel construction, a professional grouting drill is used to radially grout the broken surrounding rock of the fault outside the tunnel excavation contour to form a grouting reinforcement ring 10, thereby strengthening the integrity of the surrounding rock, improving the surrounding rock conditions to improve its own anti-dislocation and creep capabilities, thereby improving the seismic resistance of the tunnel lining support structure, and reducing groundwater leakage at the deformation joints after the active fault dislocation. Then, a full-ring steel frame 61 made of HW175 steel is installed, and then, mechanical equipment such as wet spraying manipulators are used to spray C30 high-strength concrete 62 on the rock surface of the tunnel excavation contour to fill the joints and cracks of the broken surrounding rock and produce a wedge effect, increase the friction between the excavated loose broken surrounding rock, and stick to the excavated rock layer to form a unified bearing system, improve the self-bearing capacity of the surrounding rock, reduce the force of the active fault dislocation on the secondary lining 3 structure, and the full-ring steel frame 61 and the sprayed C30 high-strength concrete 62 form an integral structure to improve the bearing capacity and anti-dislocation ability of the support structure. Next, a composite waterproof layer 2 is laid between the initial support 6 and the secondary lining 3. Next, the innermost secondary lining 3 of the tunnel structure is formed. The thickness of the secondary lining 3 is 60 cm. The secondary lining 3 is formed of C35 reinforced concrete. The rigidity of the lining support structure is improved by strengthening the reinforcement arrangement. At the same time, the lining profile is set to a nearly circular shape to improve the stress condition of the lining structure, making it more resistant to damage caused by fault dislocation.

[0040] See also Figure 5When the active fault moves, the secondary lining of each segment will move and rotate relatively independently with the active fault, and each deformation joint provides the activity space of each segment, so that the tunnel will be like a continuously curved beam with an animal spine structure when crossing the active fault fracture zone 11, so as to withstand the shear and bending of the deformed soil, thereby preventing the lining structure of the tunnel from being damaged in a large area in this area. At the same time, by reserving the secondary lining reinforcement space 4 on the radial inner side of the secondary lining 3, when the tunnel structure is damaged at the active fault fracture zone 11 and cracks appear, the secondary lining reinforcement space 4 can be used to repair the secondary lining 3 structure.

[0041] As can be seen from the above, the secondary lining structure of the tunnel is divided into long segment secondary lining, relatively long segment secondary lining and short segment secondary lining, making the tunnel a discontinuous segmented structure similar to the structure of the animal spine. Deformation joints of different widths are set between adjacent segments. The deformation joints are filled with buffers made of foam plastic boards, and a composite waterproof structure is set to make each tunnel segment relatively independent. Combined with the distribution characteristics of the active fault dislocation along the longitudinal direction of the tunnel, a certain range near the contact surface between the active fault fracture zone and the bedrock is a strong deformation zone, and the deformation of the fortified extension section near the active fault fracture zone in the middle of the fault fracture zone and the bedrock side is relatively small. The wide deformation joint is mainly set in the strong deformation zone, and the tunnel segment is the shortest within this range. When the active fault moves, the displacement in the strong deformation zone is mainly concentrated between the deformation joints with weak stiffness. The continuously set wide deformation joints can effectively share the concentrated displacement at the fault fracture zone, while each tunnel segment moves relatively independently under the action of the lateral deformation soil. In addition, narrow deformation joints are set at positions where the fault displacement is relatively small, mainly in the central position of the core of the active fault crushing zone and in the fortified extension section close to the active fault crushing zone on the bedrock side. Considering the convenience of tunnel construction, the tunnel segments in this range are relatively long. Each segment tunnel will be like a continuously curved beam when crossing the active fault crushing zone to withstand the shear and bending effects of the deformed soil.

[0042] The animal spine-simulating tunnel lining support structure system of the present invention that crosses the active fault fracture zone is arranged in the area where the tunnel crosses the active fault fracture zone, and the integrity of the surrounding rock is strengthened by grouting outside the excavation contour, and the surrounding rock conditions are improved to improve the surrounding rock's own anti-dislocation and creep capabilities. The lining structure stiffness is increased by setting a large-rigidity circular ring lining, and the structural stress conditions are improved, so that it can better resist the damage caused by the fault dislocation. When the active fault displaces, the tunnel's longitudinal short segments and wide joint structures effectively share the concentrated displacement, so that the dislocation displacement is mainly concentrated in the deformation joints with weak rigidity. Under the action of the lateral deformation soil, each segment tunnel will displace and rotate with the active fault relatively independently, and will not cause large-scale lining structure damage. The seismic fortification goal of "technically feasible, economically reasonable, and easy to repair" is achieved by reserving reinforcement space and strengthening the support system.

[0043] In addition, the length and number of the secondary linings of each segment can be changed as required. The width of each deformation joint can be changed as required. The above changes can also achieve the purpose of the present invention.

[0044] Finally, it should be emphasized that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A tunnel lining support that passes through an active fault fracture zone, comprising an initial support, a waterproof layer and a secondary lining arranged in sequence from the outside to the inside along the tunnel radial direction; Features: The secondary lining includes a segment area, and the active fault fracture zone is located in the middle of the segment area in the longitudinal direction of the tunnel; The segment area includes a plurality of segment secondary linings arranged in sequence along the longitudinal direction of the tunnel, and a deformation joint is provided between two adjacent segment secondary linings, and the deformation joint is filled with a buffer; The secondary lining of each segment can displace and rotate relatively independently under the action of the laterally deformed soil; The plurality of segment secondary liners include at least two first segment secondary liners and at least four second segment secondary liners; The first segment second lining is located in the middle of the active fault fracture zone, the second segment second lining is located near the contact surface between the active fault fracture zone and the bedrock, and at least one second segment second lining is provided at each end of the active fault fracture zone; The length of the second lining of the first section in the longitudinal direction of the tunnel is greater than the length of the second lining of the second section in the longitudinal direction of the tunnel; The deformation joint between two adjacent second linings of the first segments is a first deformation joint; At least two second segment second linings are arranged at each end of the active fault fracture zone, and the deformation joint between two adjacent second segment second linings is a second deformation joint; The width of the second deformation joint is greater than that of the first deformation joint; The plurality of segmental secondary linings further include a plurality of third segmental secondary linings, at least two third segmental secondary linings are arranged at each end of the active fault fracture zone, and the third segmental secondary linings are located at a position of the bedrock close to the active fault fracture zone; The length of the second lining of the third segment is greater than the length of the second segment and less than the length of the first segment; The plurality of segment secondary liners further include at least two fourth segment secondary liners, the fourth segment secondary liners being located between the first segment secondary liners and the second segment secondary liners; At least one of the fourth segment second linings is disposed at each end of the active fault fracture zone, and the length of the fourth segment second lining is greater than the length of the second segment and less than the length of the first segment; The deformation joint between the second lining of the fourth section and the second lining of the first section is the fourth deformation joint, and the deformation joint between the second lining of the second section and the second lining of the fourth section is the fifth deformation joint. The widths of the fourth deformation joint and the fifth deformation joint are both 5 to 8 times the width of the first deformation joint.

2. The tunnel lining support for crossing an active fault fracture zone according to claim 1 is characterized in that: The secondary lining is also provided with a second lining reinforcement space on the radial inner side of the tunnel.

3. The tunnel lining support for crossing an active fault fracture zone according to claim 1 is characterized in that: The width of the first deformation joint is in the range of 2 cm to 3 cm, and the width of the second deformation joint is 5 to 8 times the width of the first deformation joint.

4. A tunnel lining support for crossing an active fault fracture zone according to any one of claims 1 to 3, characterized in that: The length of the second segment secondary lining is in the range of 4 meters to 8 meters, and the length of the first segment secondary lining is 3 times the length of the second segment secondary lining.

5. A tunnel lining support for crossing an active fault fracture zone according to any one of claims 1 to 3, characterized in that: The length of the second lining of the third section is twice the length of the second lining of the second section; The deformation joint between two adjacent third segment second linings is a third deformation joint, and the width of the third deformation joint is in the range of 2 cm to 3 cm.

6. A tunnel lining support for crossing an active fault fracture zone according to any one of claims 1 to 3, characterized in that: The buffer is a foam plastic board, and the waterproof layer is provided with a pleated expansion shell waterproof board at the deformation joint.

7. A tunnel, characterized in that A tunnel lining support for crossing an active fault fracture zone as claimed in any one of claims 1 to 6; The tunnel lining support also includes an annular grouting reinforcement ring arranged on the broken surrounding rock outside the tunnel excavation contour, and the initial support is located radially inside the grouting reinforcement ring.

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