Correcting and resisting synergetic high-strength steel arch support system and construction method

Abstract

The invention provides a yielding-resisting synergetic high-strength steel arch support system and a construction method, the yielding-resisting synergetic high-strength steel arch support system comprises a main body steel pipe, a bag, a connecting sleeve and a longitudinal connecting device, two opposite side surfaces of two ends of the main body steel pipe are respectively provided with an annular connecting T-shaped hole, and two opposite side surfaces of the connecting sleeve are respectively provided with an I-shaped hole; the connecting sleeve is connected to the outer rings of the two adjacent sections of main steel pipes, so that the I-shaped hole just corresponds to the annular connecting T-shaped hole of the two sections of main steel pipes, the I-shaped steel is inserted into the I-shaped hole and the annular connecting T-shaped hole, connection of the connecting sleeve and the two sections of main steel pipes is achieved, and a bag is arranged on the side, close to the surrounding rock, of each main steel pipe. And in the longitudinal direction, the adjacent main steel pipes are connected through a longitudinal connecting device, and the longitudinal connecting device is of a multi-cavity yielding structure.

Description

Technical Field

[0001] This invention relates to the field of steel arch support, specifically to a high-strength steel arch support system and construction method. Background Technology

[0002] With the rapid development of tunnel construction, the construction environment faced by tunnels has become more complex. Extremely deep burial depths, high ground stress, and long fractured zones are gradually becoming new challenges for tunnel construction. Steel-concrete composite supports, with their advantages of high strength and strong load-bearing capacity, are widely used in tunnel construction in weak and fractured zones, demonstrating their advantage in controlling surrounding rock deformation. However, in high-stress, weak strata, numerous steel-concrete composite support structures still suffer from deformation and failure. The main reasons for this deformation and failure are: high stiffness and poor pressure relief capacity of the steel-concrete composite, resulting in insufficient unloading of the surrounding rock; weak longitudinal connections of the steel pipes, leading to poor overall support system coordination. To address this, some projects have adopted measures such as adding pressure relief devices to the steel pipes and strengthening longitudinal connections. However, this results in a mismatch between the high-strength longitudinal connections and the pressure relief stiffness of the steel pipes, leading to poor overall tunnel support coordination. Furthermore, existing technologies often employ rigid methods such as welding or ordinary sleeves to connect adjacent main steel pipes. While these methods can transfer loads, they cannot meet the stress release requirements of the surrounding rock. When the surrounding rock deforms, rigid connections can restrict the controllable pressure relief of the steel pipes, leading to stress concentration at the connection nodes and causing cracks in the steel pipes or connection structures. Existing connection structures (such as simple flanges and pins) have a single force transmission path, making it difficult to simultaneously transmit axial force, bending moment, and shear force. Adjacent steel pipes are prone to the problem of "each bearing its own load and failing collaboratively," resulting in uneven stiffness distribution in the overall support system and an inability to effectively disperse high ground stress. Even some reinforced connections (such as bolt-intensive flanges) involve cumbersome procedures and cannot accommodate the slight deformation of the steel pipes caused by pressure relief. After installation, issues such as loose nodes and grout leakage may occur, making it difficult to meet the rapid support requirements of soft strata. Summary of the Invention

[0003] This invention aims to overcome the defects of existing technology and provide a high-strength steel arch support system and construction method with synergistic anti-stress. Through adaptive fitting of the bladder, dense filling with special fine concrete, synergistic force bearing of multi-cavity pressure-relief steel pipes and reinforced connection structure, it achieves an integrated effect of surrounding rock adaptation, pressure relief and high load bearing, thereby improving the reliability, integrity and construction compatibility of the support structure.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a high-strength steel arch support system, comprising a main steel pipe, a bladder, a connecting sleeve, and a longitudinal connecting device: A circumferential T-shaped hole is opened on each of the two opposite sides of the main steel pipe, and an I-shaped hole is opened on each of the two opposite sides of the connecting sleeve. The connecting sleeve is connected to the outer ring of two adjacent main steel pipe sections, such that the I-shaped hole corresponds exactly to the circumferential T-shaped hole of the two main steel pipe sections. The I-shaped steel is inserted into the I-shaped hole and the circumferential T-shaped hole to achieve the connection between the connecting sleeve and the two main steel pipe sections. A bladder is provided on the side of the main steel pipe near the surrounding rock, and adjacent main steel pipes are connected by a longitudinal connecting device along the longitudinal direction. The longitudinal connecting device is a multi-cavity pressure-relief structure.

[0005] As a further technical solution, two embedded T-shaped slots are provided in the middle of the main steel pipe.

[0006] As a further technical solution, the longitudinal connecting device includes a longitudinal connecting T-shaped steel and a multi-cavity pressure-relief steel pipe. The longitudinal connecting T-shaped steel is clamped in the embedded T-shaped slot of one of the main steel pipes. The longitudinal connecting T-shaped steel is connected to one end of the multi-cavity pressure-relief steel pipe, and the other end of the multi-cavity pressure-relief steel pipe is connected to another longitudinal connecting T-shaped steel. The other longitudinal connecting T-shaped steel is clamped in the embedded T-shaped slot of another adjacent main steel pipe.

[0007] As a further technical solution, a second grouting hole is reserved on the outside of the main steel pipe to connect the bladder and the inner cavity of the steel pipe.

[0008] As a further technical solution, a first grouting hole is reserved on the outside of the main steel pipe. The first grouting hole is connected to the grouting equipment and is used to inject grout into the main steel pipe.

[0009] As a further technical solution, the bag is attached to the outside of the steel pipe body on the side close to the surrounding rock.

[0010] As a further technical solution, both the bladder and the main steel pipe are filled with concrete.

[0011] As a further technical solution, a grouting sealing plate is also included, which is equipped with a reinforcing bearing ring. The grouting sealing plate is used to seal the first grouting hole after grouting, and the outside is wrapped with carbon fiber cloth in a ring.

[0012] As a further technical solution, an annular grouting plug is also provided between the end of the connecting sleeve and the end of the main steel pipe.

[0013] Secondly, based on the aforementioned high-strength steel arch support system with strong resistance to impact, this invention provides a construction method, as follows: Step 1: Tunnel Excavation Step 2, Steel Arch Frame Installation: Using a combination of connecting sleeves and I-beams, the segmented steel pipe body is assembled into a steel pipe concrete arch frame; the steel pipe concrete arch frame is precisely fixed in the design position using temporary support devices to ensure that all parameters meet the support design requirements; simultaneously, the gasket is firmly attached to the outside of the steel pipe on the side closest to the surrounding rock, and the joint is compacted and sealed to ensure that the gasket is installed stably, sealed reliably, and without any loosening or leakage risks; Step 3, Grouting and Filling: High-strength fine concrete grout is injected under high pressure into the main cavity of the steel pipe. During the grouting process, the trapped air in the cavity is discharged using a grouting bag to ensure that the concrete is filled densely and without voids. Fine concrete is injected simultaneously through the second grouting hole reserved in the steel pipe, so that the grouting bag expands evenly and the steel pipe concrete arch frame is tightly bonded to the irregular surrounding rock to form the initial support interface. After the grouting is completed, the concrete is cured according to the specifications to ensure the concrete strength. Step 4: Grouting Hole Sealing and Reinforcement: After the fine concrete grout inside the steel pipe body reaches its initial setting strength, thoroughly clean the laitance and debris from the surface of the steel pipe outside the grouting hole; use a grouting sealing plate to seal the grouting hole to ensure a tight seal; then use a special structural adhesive to wrap carbon fiber cloth in a ring around the outside of the reinforcing sealing plate and the surrounding steel pipe surface, compact and smooth the carbon fiber cloth to ensure that it is tightly bonded to the steel pipe body and the grouting sealing plate without voids, significantly enhancing the structural integrity and crack resistance of the grouting hole area; Step 5, T-shaped steel connection: After the grouting concrete of the steel arch frame reaches the standard, the longitudinal connecting T-shaped steel is precisely inserted between the reserved circumferential connecting T-shaped holes of the adjacent circumferential steel arch frames. The longitudinal connecting T-shaped steel is then connected to the multi-cavity pressure-relief steel pipe to form a continuous and complete longitudinal force transmission support system, which effectively improves the overall stiffness, stability and load adjustment capacity of the support structure.

[0014] Step 6, Shotcrete Protection: After the T-steel connection is completed, shotcrete is sprayed onto the outside of the steel arch frame, the surface of the bag, and the entire cross-section of the tunnel surrounding rock to ensure that the concrete fully covers all support components and the surface of the surrounding rock, forming a composite support structure of "surrounding rock-shotcrete-steel arch frame" working together to significantly enhance the integrity, load-bearing capacity and long-term stability of the support system.

[0015] Compared with the prior art, the outstanding advantages and beneficial effects of the present invention are as follows: 1. The main steel pipe of the present invention has a circumferential T-shaped hole on each of its two opposite sides, and an I-shaped hole on each of its two opposite sides. The connecting sleeve is connected to the outer ring of two adjacent main steel pipe sections, so that the I-shaped hole corresponds exactly to the circumferential T-shaped hole of the two main steel pipe sections. The I-shaped steel is inserted into the I-shaped hole and the circumferential T-shaped hole to realize the connection between the connecting sleeve and the two main steel pipe sections. The axial force, bending moment and shear force are transmitted synchronously through the flange and web of the I-shaped steel. Combined with the sleeve wrapping, the load is evenly distributed, avoiding the local stress concentration of traditional connections. At the same time, the embedded structure is a "semi-rigid + slightly deformable" design, which not only maintains the conventional stiffness to prevent loosening, but also adapts to the compression deformation of the steel pipe, solving the problem of traditional rigid connections restricting compression and easy cracking. Moreover, the contact area of ​​the node is greatly increased, the shear and bending bearing capacity is improved, the hidden danger of welding embrittlement is avoided, and it can stably bear the multidimensional loads of complex strata.

[0016] 2. The present invention has strong adaptability to surrounding rock: through the grouting expansion design of the bag, the gaps in the surrounding rock are precisely filled, achieving a tight fit with irregular surrounding rock and avoiding stress concentration; at the same time, the multi-chamber of the integrated multi-cavity pressure relief device can perform graded and coordinated deformation to complete the "second-stage precise pressure relief and unloading", forming a progressive stress adjustment with the initial pressure relief of the bag, completely avoiding local stress concentration in the structure; 3. Excellent anti-stress performance: The integrated multi-cavity pressure relief device and high-strength steel-concrete composite structure not only achieve pressure relief and load reduction through multi-cavity stress, but also rely on steel-concrete composite and reinforced connection structure to ensure load-bearing capacity; 4. Convenient and efficient construction: The modular assembly design simplifies the steel pipe connection, T-shaped steel connection, and grouting sealing process. The carbon fiber reinforcement process is easy to operate and adapts to on-site construction needs. 5. Dense and reliable structure: Through optimized venting, rubber plugs to prevent grout leakage, and carbon fiber cloth reinforcement design, problems such as insufficient filling and leakage of grouting holes are solved, thereby improving the long-term stability of the support. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 This is a schematic diagram of the steel-concrete arch frame connection of the system of the present invention; Figure 2 This is a diagram of the independent steel pipe support of the present invention; Figure 3 This is a schematic diagram of the embedded T-shaped groove in an independent steel pipe; Figure 4 This is a schematic diagram of a vertical connection of independent steel pipes; Figure 5This is a schematic diagram of the longitudinal connection of a steel-concrete composite arch frame; Figure 6 This is a schematic diagram of the grouting sealing plate; Figure 7 This is a schematic diagram of the connecting sleeve; In the diagram: 1. Grouting bag, 2. Longitudinal connecting device, 3. Grouting sealing plate, 4. Circumferential connecting I-beam, 5. Connecting sleeve, 6. Steel pipe concrete arch, 7. Main steel pipe, 8. Circumferential connecting T-hole, 9. Embedded T-slot, 10. First grouting hole, 11. Second grouting hole, 12. Ring-shaped grouting plug, 13. I-beam grouting plug, 14. Multi-cavity pressure-relief steel pipe, 15. Longitudinal connecting T-beam, 16. Reinforcing bearing ring. Detailed Implementation It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0019] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. For ease of description, the words "up," "down," "left," and "right" appearing in this invention only indicate that they are consistent with the up, down, left, and right directions of the accompanying drawings themselves, and do not limit the structure. They are merely for the purpose of facilitating the description of this invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] As described in the background section, there are shortcomings in the existing technology. In order to solve the above-mentioned technical problems, this invention proposes a steel arch support system with high resistance to stress.

[0021] This embodiment discloses a high-strength steel arch support system with synergistic load-bearing capacity and flexible pressure relief. The system is built around the concept of "high-strength load-bearing capacity + flexible pressure relief" and includes a main steel pipe 7, a polyester fiber reinforced rubber bladder 1, a connecting sleeve 5, and a longitudinal connecting device 2. Multiple main steel pipes 7 are connected together by multiple connecting sleeves 5 to form an arch structure. A bag 1 is set on the side of the arch structure near the surrounding rock. Along the longitudinal direction, adjacent main steel pipes 7 are connected by a longitudinal connecting device 2. Among them, the main steel pipe 7 is a core component integrating load bearing and pressure relief, and its structure is as follows: Figure 2 As shown, two first grouting holes 10 are reserved on the outside of the main steel pipe 7, respectively connecting the bladder and the inner cavity of the steel pipe; a second grouting hole 11 is also reserved on the outside of the main steel pipe. The first grouting holes 10 are connected to grouting equipment for grouting into the main steel pipe; two circumferential connecting T-shaped holes 8 are reserved at the top and bottom of the main steel pipe 7, and the two circumferential connecting T-shaped holes 8 are set on the front and rear sides of the main steel pipe 7 and are symmetrically arranged; two embedded T-shaped slots 9 are provided at the middle position of the front and rear sides of the main steel pipe 7, and the embedded T-shaped slots 9 on the front side and the embedded T-shaped slots 9 on the rear side are symmetrically arranged; wherein, the injection of high-strength fine concrete through the first grouting holes 10 not only ensures the dense filling of the cavity to enhance the bearing capacity, but also provides a rigidity basis for the pressure relief coordination of the multi-cavity pressure-relief steel pipe structure; Grouting is performed into the bladder through the second grouting hole 11; the circumferential connecting T-hole 8 at the upper end of the main steel pipe 7 and the circumferential connecting T-hole 8 at the lower end of another main steel pipe 7 are combined to form an I-shaped hole, and the circumferential connecting T-hole 8 at the lower end of the main steel pipe 7 and the circumferential connecting T-hole 8 at the upper end of another main steel pipe 7 are also combined to form an I-shaped hole; circumferential connecting I-beams 4 are inserted into each I-shaped hole to form a "flange + web" structure; and two matching I-beam grouting plugs 13 are inserted into the I-shaped holes to prevent grout leakage and achieve the connection of the main steel pipes 7; axial force, bending moment and shear force are transmitted synchronously through the flange and web of the I-beam, and combined with the sleeve wrapping, the load is evenly distributed to avoid local stress concentration in traditional connections; at the same time, the interlocking structure is "semi-rigid + The "micro-deformable" design maintains conventional stiffness and prevents loosening while adapting to the deformation of the steel pipe under pressure, solving the problem of traditional rigid connections being prone to cracking under pressure. Furthermore, the contact area of ​​the nodes is greatly increased, improving shear and bending bearing capacity, avoiding the risk of welding embrittlement, and can stably bear multidimensional loads in complex strata.

[0022] Furthermore, the aforementioned embedded T-shaped slot 9 is used to realize the connection of the longitudinal connecting device 2.

[0023] Furthermore, such as Figure 5 As shown, the connecting sleeve 5 in this embodiment is a rectangular sleeve with two I-shaped holes on its two opposite surfaces. The connecting sleeve 5 is connected to the outer ring of two adjacent main steel pipe sections 7, so that the I-shaped holes correspond exactly to the circumferential connecting T-shaped holes of the two main steel pipe sections. The circumferential connecting I-shaped steel 4 is inserted into the I-shaped holes and the circumferential connecting T-shaped holes 8 to realize the connection between the connecting sleeve 5 and the two main steel pipe sections 7. Furthermore, an annular grouting plug 12 is provided between the end of the connecting sleeve 5 and the two main steel pipe sections 7 to seal the gap formed between the end of the sleeve 5 and the two main steel pipe sections 7.

[0024] Furthermore, the bag 1 is attached to the outer side of the main steel pipe near the surrounding rock end. After grouting through the grouting hole, the gap between the surrounding rock is first filled with flexible expansion to achieve a close fit. When the stress of the surrounding rock increases, the surface stress can be initially released through controllable deformation to achieve "initial flexible pressure relief". Furthermore, the aforementioned longitudinal connection device 2 includes a longitudinal connecting T-shaped steel 15 and a multi-cavity pressure-relief steel pipe 14. The longitudinal connecting T-shaped steel 15 is fitted into an embedded T-shaped slot 9 in one of the main steel pipes 7. The longitudinal connecting T-shaped steel 15 is connected to one end of the multi-cavity pressure-relief steel pipe 14, and the other end of the multi-cavity pressure-relief steel pipe 14 is connected to another longitudinal connecting T-shaped steel 15. The other longitudinal connecting T-shaped steel 15 is fitted into an embedded T-shaped slot 9 in another adjacent main steel pipe 7. The longitudinal connection of the circumferential steel arch frame is achieved through the longitudinal connecting T-shaped steel 15 and the multi-cavity pressure-relief steel pipe 14. The longitudinal connecting T-shaped steel 15 connects to the multi-cavity pressure-relief steel pipe 14. When the surrounding rock stress is further transmitted to the steel arch frame, the multi-cavity chambers can undergo graded and coordinated deformation to complete the "second-stage precise pressure relief and unloading", forming a progressive stress adjustment with the initial pressure relief of the bladder, thus completely avoiding local stress concentration in the structure. Furthermore, it also includes a grouting sealing plate 3, which is equipped with a reinforcing bearing ring 16. The grouting sealing plate 3 is used to seal the first grouting hole 10 after grouting. The outer side is wrapped with carbon fiber cloth in a ring to enhance the crack resistance and sealing of the grouting hole area and ensure the overall stability of the structure during the pressure relief process.

[0025] The specific construction method for the aforementioned high-strength steel arch support system is as follows: (1) Tunnel excavation: strictly follow the underground engineering construction specifications to complete the tunnel section excavation operation, thoroughly clean the floating slag and dangerous rocks on the surface of the surrounding rock, carefully trim the rock wall outline, and ensure that there are no loose blocks and weak interlayers on the surface of the surrounding rock, so as to create a stable and safe working foundation for the subsequent support structure construction.

[0026] (2) Steel arch frame installation: The main steel pipe 7, which is processed in sections, is assembled into a steel pipe concrete arch frame 6 by using a combination of connecting sleeve 5 and circumferential connecting I-beam 4; the steel pipe concrete arch frame 6 is precisely fixed in the design position by temporary support device to ensure that all parameters meet the support design requirements; at the same time, the polyester fiber reinforced rubber bag 1 is firmly pasted on the outside of the steel pipe near the surrounding rock, and the interface is compacted and sealed to ensure that the bag is installed firmly and reliably, without any loosening or leakage.

[0027] (3) Grouting and filling: High-strength fine concrete grout is injected into the main steel pipe 7 cavity under high pressure. During the grouting process, the air trapped in the cavity is discharged by the bladder 1 to ensure that the concrete is filled densely and without voids. Fine concrete is injected synchronously through the special grouting hole reserved in the steel pipe bladder to make the bladder expand evenly and make the steel pipe concrete arch 6 fit tightly with the irregular surrounding rock to form the initial support interface. After the grouting is completed, the concrete is cured in accordance with the specifications to ensure the concrete strength.

[0028] (4) Grouting hole sealing and reinforcement: After the fine concrete grouting inside the main steel pipe 7 reaches the initial setting strength, thoroughly clean the floating slurry and debris on the surface of the steel pipe outside the grouting hole 10; use the grouting sealing plate 3 to seal the first grouting hole 10 to ensure tight sealing; then use a special structural adhesive to wrap the carbon fiber cloth in a ring around the outside of the reinforcing sealing plate and the surface of the surrounding steel pipe, compact and smooth the carbon fiber cloth to ensure that it is tightly attached to the main steel pipe 7 and the grouting sealing plate 3 without voids, which significantly enhances the structural integrity and crack resistance of the grouting hole area.

[0029] (5) T-shaped steel connection: After the grouting concrete of the steel arch frame reaches the standard, the longitudinal connecting T-shaped steel 15 is precisely inserted between the reserved embedded T-shaped slots 9 of the adjacent steel arch frames in the circumferential direction. The longitudinal connecting T-shaped steel 15 is connected to the multi-cavity pressure-relief steel pipe 14 to form a continuous and complete longitudinal force transmission support system, which effectively improves the overall stiffness, stability and load adjustment capacity of the support structure. The multi-cavity pressure-relief steel pipe 14 can make the pressure relief effect more prominent. The multi-cavity compartments are deformed in stages according to the stress gradient of the surrounding rock to release stress smoothly. Its deformation is progressively adjusted with the initial pressure relief of the bag and the slight deformation of the connection node, which not only prevents excessive pressure relief and instability, but also avoids excessive rigidity and cracking, so that the deformation of the surrounding rock is controlled within the design allowable range and the long-term stability of the support is guaranteed.

[0030] (6) Shotcrete protection: After the T-shaped steel is connected, shotcrete is sprayed onto the outside of the steel arch frame, the surface of the bag and the entire cross section of the tunnel surrounding rock to ensure that the concrete fully covers all support components and the surface of the surrounding rock, forming a composite support structure of “surrounding rock-shotcrete-steel arch frame” to significantly enhance the integrity, load-bearing capacity and long-term stability of the support system.

[0031] Finally, it should be noted that relational terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0032] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-strength steel arch support system with strong anti-collision properties, characterized in that, The system comprises a main steel pipe, a bladder, a connecting sleeve, and a longitudinal connecting device. The main steel pipe has a circumferential T-shaped hole on each of its two opposite sides. The connecting sleeve has an I-shaped hole on each of its two opposite sides. The connecting sleeve connects to the outer ring of two adjacent main steel pipe sections, such that the I-shaped holes correspond precisely to the circumferential T-shaped holes of the two main steel pipe sections. The I-shaped steel is inserted into the I-shaped holes and the circumferential T-shaped holes to connect the connecting sleeve to the two main steel pipe sections. A bladder is provided on the side of the main steel pipe near the surrounding rock. Adjacent main steel pipe sections are connected longitudinally via a longitudinal connecting device, which is a multi-cavity pressure-relief structure.

2. The high-strength steel arch support system as described in claim 1, characterized in that, Two embedded T-shaped slots are provided in the middle of the main steel pipe.

3. The high-strength steel arch support system as described in claim 2, characterized in that, The longitudinal connecting device includes a longitudinal connecting T-shaped steel and a multi-cavity pressure-relief steel pipe. The longitudinal connecting T-shaped steel is clamped in the embedded T-shaped slot of one of the main steel pipes. The longitudinal connecting T-shaped steel is connected to one end of the multi-cavity pressure-relief steel pipe, and the other end of the multi-cavity pressure-relief steel pipe is connected to another longitudinal connecting T-shaped steel. The other longitudinal connecting T-shaped steel is clamped in the embedded T-shaped slot of another adjacent main steel pipe.

4. The high-strength steel arch support system as described in claim 1, characterized in that, A second grouting hole is reserved on the outside of the main steel pipe to connect the bladder and the inner cavity of the steel pipe.

5. The high-strength steel arch support system as described in claim 1, characterized in that, A first grouting hole is reserved on the outside of the main steel pipe. The first grouting hole is connected to the grouting equipment and is used to inject grout into the main steel pipe.

6. The high-strength steel arch support system as described in claim 1, characterized in that, It also includes a grouting sealing plate with a reinforcing bearing ring. The grouting sealing plate is used to seal the first grouting hole after grouting, and the outside is wrapped with carbon fiber cloth in a ring.

7. The high-strength steel arch support system as described in claim 1, characterized in that, The bag is attached to the outside of the steel pipe body on the side close to the surrounding rock.

8. The high-strength steel arch support system as described in claim 1, characterized in that, Both the bladder and the main steel pipe are filled with concrete.

9. The high-strength steel arch support system as described in claim 1, characterized in that, A ring-shaped grouting plug is also installed between the end of the connecting sleeve and the end of the main steel pipe.

10. The construction method of the high-strength steel arch support system as described in any one of claims 1-9, characterized in that, as follows: Step 1: Tunnel excavation; Step 2: Using a combination of connecting sleeves and I-beams, the segmented steel pipe body is assembled into a steel pipe concrete arch frame; the steel pipe concrete arch frame is precisely fixed in the design position using temporary support devices to ensure that all parameters meet the support design requirements; at the same time, the bag is firmly pasted to the outside of the steel pipe on the side close to the surrounding rock, and the joint is compacted and sealed. Step 3: High-strength fine concrete grout is injected under high pressure into the main cavity of the steel pipe. During the grouting process, the trapped air in the cavity is discharged using a grouting bag to ensure that the concrete is filled densely and without voids. Fine concrete is injected simultaneously through the second grouting hole reserved in the steel pipe to make the grouting bag expand evenly and make the steel pipe concrete arch frame fit tightly against the irregular surrounding rock to form the initial support interface. After the grouting is completed, the concrete is cured according to the specifications to ensure the concrete strength. Step 4: Grouting Hole Sealing and Reinforcement: After the fine concrete grout inside the steel pipe body reaches its initial setting strength, thoroughly clean the laitance and debris from the surface of the steel pipe outside the grouting hole; use a grouting sealing plate to seal the grouting hole, ensuring a tight seal; then wrap carbon fiber cloth in a ring around the outside of the reinforcing sealing plate and the surrounding steel pipe surface, compact and smooth the carbon fiber cloth to ensure that it fits tightly with the steel pipe body and the grouting sealing plate without voids, significantly enhancing the structural integrity and crack resistance of the grouting hole area; Step 5: After the concrete strength of the steel arch frame reaches the standard, accurately insert longitudinal connecting T-shaped steel between the reserved circumferential connecting T-shaped holes of adjacent circumferential steel arch frames, and connect the longitudinal connecting T-shaped steel with the multi-cavity pressure-relief steel pipe to form a continuous and complete longitudinal force transmission support system. Step 6: After the T-shaped steel is connected, spray concrete onto the outside of the steel arch frame, the surface of the bag, and the entire cross-section of the tunnel surrounding rock to ensure that the concrete fully covers all support components and the surface of the surrounding rock, forming a composite support structure in which the surrounding rock, sprayed concrete, and steel arch frame work together to bear the load.

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