Hundred-meter deep water rigid connection immersed tube tunnel structure

Abstract

The utility model relates to tunnel engineering technical field especially relates to a hundred meters level deepwater rigid connection immersed tube tunnel structure, the utility model provides a hundred meters level deepwater rigid connection immersed tube tunnel structure, including pipe section and rigid connection structure, pipe section adopts steel shell concrete combination structure, and the roof of pipe section adopts the arch section;Rigid connection structure sets up between two pipe sections of adjacent, is used for connecting two pipe sections in extension direction, the utility model provides deepwater immersed tube tunnel structure has excellent bearing performance, reliable waterproof sealing capacity and good structural integrity, can satisfy hundred meters level deepwater environment under long -term safe operation.

Description

Technical Field

[0001] This utility model relates to the field of tunnel engineering technology, and in particular to a rigid connection immersed tube tunnel structure for deep water at a depth of 100 meters. Background Technology

[0002] With the increasing demand for cross-sea transportation, immersed tunnels have been widely used as an important technology for constructing cross-sea channels. Immersed tunnels have advantages such as low burial depth requirements, good seismic performance, and easy onshore connection, playing an important role in cross-sea projects worldwide.

[0003] However, as the application of immersed tunnels expands to deeper and more complex sea areas, traditional immersed tunnel technology faces severe challenges. Especially in deep-water environments of hundreds of meters, immersed tunnels need to withstand enormous external water pressure, placing extremely high demands on the strength, rigidity, and waterproofing performance of the structure.

[0004] Traditional immersed tunnels often use flexible connection methods between pipe sections, such as GINA rubber waterstops and OMEGA rubber waterstops. This connection method can adapt to a certain degree of joint deformation, but under the action of deep water and high pressure at depths of hundreds of meters and uneven foundation, problems such as excessive joint opening leading to water seepage in the pipe section can easily occur, seriously affecting the operational safety of the tunnel.

[0005] In addition, the traditional design of the top plate of the immersed tunnel segment mostly adopts a flat plate structure, which is prone to excessive bending moment at mid-span under the action of high water pressure of hundreds of meters. If a reinforced concrete structure is used, the plate thickness or the amount of steel reinforcement needs to be increased to meet the strength requirements. If a steel shell concrete composite structure is used, steel plates with a thickness of more than 50mm are still required, resulting in material waste and increased construction difficulty.

[0006] Based on the above analysis, the main technical problems faced by traditional immersed tunnel technology in deep-water environments of hundreds of meters are: the internal forces of the traditional pipe section cross-section are too large, resulting in poor engineering economy and high construction difficulty; the opening of the flexible joint of the pipe section is difficult to control, the risk of water leakage is high, and there are safety hazards during the operation period. Utility Model Content

[0007] This utility model provides a rigid connection immersed tunnel structure for deep water at a depth of 100 meters. This rigid connection immersed tunnel structure for deep water at a depth of 100 meters has excellent load-bearing performance, reliable waterproof sealing capability and good structural integrity, and can meet the requirements for long-term safe operation in deep water environment.

[0008] This utility model provides a rigid connection immersed tunnel structure for deep water at a depth of 100 meters, comprising: a pipe section, wherein the pipe section adopts a steel shell concrete composite structure and the top plate of the pipe section adopts an arched cross section; and a rigid connection structure, which is set between two adjacent pipe sections for connecting the two pipe sections in the extension direction.

[0009] In one possible implementation, the top plate includes: a crane hole top plate, which has a circular arched cross-section; and a utility tunnel top plate, which is located between the two crane hole top plates and has a flat plate structure.

[0010] In one possible implementation, the arched cross-section is a three-centered circular arched cross-section, comprising a main circular arc and two side circular arcs tangentially connected to it.

[0011] In one possible implementation, the radius R of the main arc satisfies: 8m ≤ R ≤ 13m, and the radius r of the side arc satisfies: 1m ≤ r ≤ 3m.

[0012] In one possible implementation, the steel-concrete composite structure includes: an inner steel panel; an outer steel panel disposed outside the inner steel panel, forming a filling gap between the inner and outer steel panels; a connecting component disposed in the filling gap, connecting the inner and outer steel panels; and a cast-in-place body filling the filling gap.

[0013] In one possible implementation, the rigid connection structure includes: a cable mechanism for connecting two adjacent pipe sections; a cast-in-place layer disposed on the water-facing side between the two pipe sections; and a sealing assembly disposed on the free surface between the two pipe sections.

[0014] In one possible implementation, the sealing assembly includes: an end steel shell connected to the end of the pipe section, the end steel shell having an abutment portion that conforms to the cast-in-place layer; a waterstop strip disposed between the two end steel shells, the two ends of the waterstop strip abutting against the two end steel shells respectively; and a seal connecting the two abutment portions; wherein the two abutment portions and the seal form an isolation surface, the isolation surface being used to isolate the cast-in-place layer and the sealing assembly.

[0015] In one possible implementation, the cable mechanism includes: a PC cable, pre-embedded in the end of the pipe section; and a connecting sleeve, connecting the two PC cables.

[0016] In one possible implementation, the water-facing surfaces of the pipe sections are coated with glass flake paint; and / or, the free-faced surfaces of the pipe sections are coated with epoxy zinc-rich primer.

[0017] In one possible implementation, the tube segment is equipped with a sacrificial anode.

[0018] This utility model provides a 100-meter-class deep-water rigid-connection immersed tunnel structure. By employing a steel-shell-concrete composite structure for the tunnel sections and a rigid connection structure, it effectively solves the core technical problems of insufficient structural strength, poor waterproofing, and inadequate overall integrity in traditional immersed tunnel technology under deep-water and high-pressure environments. The steel-shell-concrete composite structure fully leverages the tensile strength of steel and the compressive strength of concrete. The steel shell forms a continuous tensile skeleton, avoiding the weak points of discontinuous reinforcement distribution in traditional reinforced concrete. The two materials work together to form an efficient composite stress system, significantly improving the structure's load-bearing capacity and reliability under deep-water and high-pressure environments. The arched cross-section of the tunnel section utilizes the excellent pressure transmission characteristics of the arch structure to convert external loads into axial pressure transmitted along the arch curve, avoiding the problem of excessive mid-span bending moment in flat plate structures, achieving uniform stress distribution and efficient material utilization. The rigid connection structure connects independent tunnel sections into a continuous whole through the combined action of prestressing and post-cast concrete. Compared with traditional flexible connections, it has higher connection strength and better deformation control, effectively preventing joint opening and relative displacement, ensuring the long-term sealing and structural integrity of the tunnel. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a cross-sectional structural diagram of a pipe section provided by this utility model.

[0021] Figure 2 yes Figure 1 The diagram shows the structure of the arched end face of the pipe section.

[0022] Figure 3 This is a schematic cross-sectional view of a rigidly connected immersed tunnel structure for deep water at a depth of 100 meters, provided by this utility model, along its extension direction.

[0023] Figure 4 This is a structural diagram of an immersed tunnel in the existing technology.

[0024] Figure 5 This is a structural diagram of another existing immersed tunnel structure.

[0025] Figure 6 This is a flowchart of a construction method for a deep-water immersed tunnel structure provided by this utility model.

[0026] Figure label: 1. Pipe section; 11. Top plate; 111. Crane hole top plate; 112. Pipe gallery top plate; 12. Main arc; 13. Side arc; 2. Rigid connection structure; 21. Cable mechanism; 211. PC cable; 212. Connecting sleeve; 22. Cast-in-place layer; 23. Sealing component; 231. End steel shell; 2311. Abutment part; 232. Waterstop; 233. Sealing element. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0028] The following is combined Figure 1-3 This utility model provides a rigidly connected immersed tunnel structure for deep water up to 100 meters deep, including a tunnel segment 1 and a rigid connection structure 2, wherein: Pipe section 1 adopts a steel-concrete composite structure, and the top plate 11 of pipe section 1 adopts an arched cross section.

[0029] A rigid connection structure 2 is provided between two adjacent pipe sections 1 for connecting the two pipe sections 1 in the extension direction.

[0030] In this invention, the use of a steel-shell concrete composite structure for the pipe section 1 and a rigid connection structure 2 between adjacent pipe sections 1 achieves the beneficial effects of high-strength load-bearing capacity and reliable connection for immersed tunnels in deep-water environments. The steel-shell concrete composite structure fully utilizes the high tensile strength of steel and the good compressive strength of concrete, effectively resisting external water pressure in deep-water, high-pressure environments. Simultaneously, the arched cross-section of the top plate 11 of the pipe section 1 utilizes the pressure transmission mechanism of the arched structure to evenly distribute external loads throughout the entire structure, avoiding localized stress concentration. The rigid connection structure 2 connects two adjacent pipe sections 1 in the extension direction, forming a continuous integral structure, ensuring the structural integrity and stability of the tunnel during use.

[0031] Specifically, the steel-concrete composite structure of pipe section 1 means that steel and concrete form a composite material system in the structure of pipe section 1. The steel bears tensile stress, and the concrete bears compressive stress. The two materials work together to maximize their respective material advantages. The arched cross-section of the top plate 11 of pipe section 1 means that the top structure of pipe section 1 adopts an arc-shaped geometry. When subjected to external loads, this shape can convert the load into axial pressure through the geometric characteristics of the arch, and transfer it to the support point along the arch curve, thereby effectively dispersing stress. The rigid connection structure 2 is set between two adjacent pipe sections 1 to connect the two pipe sections 1 in the extension direction. It means that the independent pipe section 1 units are connected into a continuous tunnel structure through a rigid connection. Compared with flexible connection, this connection method can better maintain the relative positional relationship between pipe sections 1 and reduce joint deformation.

[0032] In deep-water immersed tunnel projects, the length of each tunnel segment is typically 100-200 meters. The entire tunnel is composed of multiple connected segments, with a total length ranging from several kilometers to tens of thousands of meters. In long-distance tunnels, the connection method between segments directly affects the overall structural performance. Traditional flexible connections suffer from cumulative deformation in long-distance applications, and the superposition of small displacements at multiple joints can cause discontinuities and stress redistribution in the overall structure. The rigid connection structure of this invention uses prestressed cables in conjunction with cast-in-place concrete to firmly connect adjacent segments into a whole, eliminating relative displacement between segments and creating a continuous tunnel structure. The load is rationally distributed and transferred throughout the entire tunnel, avoiding localized stress concentrations caused by flexible connections. The rigid connection ensures the structural continuity and integrity of long-distance tunnels, providing technical assurance for safe operation in deep-water environments.

[0033] In one specific embodiment, when deep-water immersed tunnels are applied to subsea tunnel projects, the water depth may reach over 80 meters, at which point the external water pressure can exceed 0.8 MPa. The steel-concrete composite structure of tunnel segment 1 can withstand such high water pressure, with the steel shell providing tensile strength and the concrete providing compressive strength and overall rigidity. The arched cross-section design allows the pressure on the top plate 11 of tunnel segment 1 to be transmitted to both sides along the arched curve when subjected to water pressure, avoiding the stress concentration problem that may occur in the middle of a flat structure. The rigid connection structure 2 ensures that adjacent tunnel segments 1 maintain their integrity under external forces such as water flow impact and earthquakes, avoiding problems such as misalignment and cracking at the joints, thereby ensuring the safe operation of the tunnel. In actual engineering, this technical solution has proven to be able to operate stably for a long time in complex deep-water environments, providing a reliable passage for subsea transportation.

[0034] In related technologies, traditional immersed tunnels mainly adopt reinforced concrete structures with rectangular frame cross-sections (as shown in the attached diagram). Figure 4 (as shown) and the cross-section of the folded frame (as attached) Figure 5The reinforced concrete structure shown (indicated by the diagram) employs a flexible connection method between pipe sections 1. While traditional reinforced concrete structures possess good compressive strength, their tensile strength is relatively insufficient in deep-water, high-pressure environments, making them prone to cracking at points of tensile stress concentration, thus affecting the structure's waterproofing performance and service life. Although flexible connections can accommodate certain deformations, relative displacement can easily occur at the joints during long-term use, leading to waterproofing failure and structural instability. Furthermore, the top plate 11 of traditional pipe section 1 often adopts a flat plate or a simple arched structure, which is not optimized for stress performance in deep-water environments and results in low material utilization.

[0035] In this embodiment of the invention, the steel-concrete composite structure exhibits superior overall performance compared to traditional reinforced concrete. The steel shell provides a continuous tensile skeleton, avoiding weak points that may result from discontinuous reinforcement in reinforced concrete. Simultaneously, the steel shell provides excellent restraint for the concrete, improving its compressive strength and toughness. The arched cross-section design, compared to a flat plate structure, more effectively utilizes the compressive strength of the material, bearing greater external loads with the same material usage. The rigid connection structure 2, compared to a flexible connection, better maintains the integrity of the tunnel, reduces joint deformation, and improves the long-term stability of the structure. This combination of technical solutions achieves a comprehensive improvement in the structural strength, waterproofing performance, and service life of immersed tunnels in deep-water environments, providing a more reliable and economical solution for deep-water tunnel engineering.

[0036] like Figure 1 As shown, in some embodiments, the top plate 11 includes: a crane hole top plate 111, which has a circular arched cross section; and a pipe gallery top plate 112, which is disposed between the two crane hole top plates 111 and has a flat plate structure.

[0037] In this invention, by dividing the top plate 11 into two functional areas—a crane opening top plate 111 and a pipe gallery top plate 112—and adopting different structural forms, the beneficial effects of functional zoning optimization and structural stress rationalization are achieved. The crane opening top plate 111, with its arched cross-section, can effectively withstand vehicle loads and dynamic impacts. The geometric characteristics of the arch allow the load to be evenly distributed throughout the arched structure, avoiding localized stress concentration. The pipe gallery top plate 112, located between the two crane opening top plates 111, adopts a flat plate structure, saving materials while meeting the functional requirements of the pipe gallery space. The flat plate structure facilitates the installation and maintenance of equipment pipelines. This zoning design achieves structural optimization of different functional areas, improving the overall structure's economy and practicality.

[0038] Specifically, there are two traffic tunnels, with a utility tunnel between them. The top of each traffic tunnel is a tunnel top plate 111, and the top of the utility tunnel is a utility tunnel top plate 112. The tunnel top plate 111 adopts a circular arch cross-section, meaning the structure above the traffic tunnel uses an arc-shaped geometry. This shape, when bearing vehicle loads, can convert the load into axial pressure through the arched force mechanism, transferring it along the arc to the supporting structure, thus effectively dispersing stress and avoiding excessive bending stress. The utility tunnel top plate 112 is located between the two tunnel top plates 111, meaning a dedicated utility tunnel space is provided between the two traffic tunnels for arranging various equipment pipelines. This arrangement separates traffic functions from equipment functions. The utility tunnel top plate 112 is a flat plate structure, meaning the top of the utility tunnel uses a straight, plate-like structure. This structural form is simple, easy to construct, and provides a regular space inside the utility tunnel.

[0039] In one specific embodiment, when the deep-water immersed tunnel is used as an intercity undersea highway tunnel, the navigable passage needs to withstand the passage of heavy-duty vehicles such as trucks. The navigable passage roof slab 111 adopts a circular arched cross-section design. When heavy vehicles pass, the dynamic and static loads generated are effectively distributed through the force-bearing mechanism of the arched structure, avoiding the problem of excessive mid-span bending moment that may occur with flat slab structures. The pipe gallery roof slab 112 area is used to house various facilities such as ventilation ducts, cable trays, fire-fighting pipes, and lighting equipment. The flat slab structure facilitates the installation of these devices and reduces construction complexity. In actual operation, this zoning design makes the traffic area and equipment area independent of each other, facilitating their respective maintenance and management. When equipment maintenance is required, it will not affect normal traffic flow, improving the tunnel's operational efficiency and safety.

[0040] In related technologies, the design of the roof slab of traditional immersed tunnels often adopts a uniform structural form, which cannot well adapt to the stress characteristics and usage requirements of different functional areas. Although the uniform flat plate structure is simple to construct, it is not reasonably stress-bearing when subjected to vehicle loads, and is prone to problems such as excessive bending moments at mid-span. It is necessary to increase the slab thickness or the amount of steel reinforcement to meet the strength requirements, resulting in material waste. Although the uniform arch structure has good load-bearing performance, it increases the spatial height of the utility tunnel area, which is not conducive to the layout of equipment pipelines, and also increases the construction complexity and cost.

[0041] In this embodiment of the invention, the differentiated design of the overhead duct top plate 111 and the utility tunnel top plate 112 fully considers the characteristics and needs of different functional areas. The overhead duct top plate 111 adopts a circular arched cross-section, which provides more reasonable stress distribution when bearing vehicle loads and can withstand larger loads with smaller cross-sectional dimensions, achieving efficient material utilization. The utility tunnel top plate 112 adopts a flat plate structure, providing maximum usable height for the utility tunnel space while meeting load-bearing requirements, facilitating the layout and maintenance of various equipment pipelines. Compared with the traditional uniform structural form, this zoned optimization design achieves material savings, reduced construction complexity, and optimized functionality while ensuring structural safety, thus improving the overall benefits of deep-water immersed tunnel projects.

[0042] like Figure 2 As shown, in some embodiments, the arched cross-section is a three-centered circular arched cross-section, including a main circular arc 12 and two side circular arcs 13 tangentially connected to it.

[0043] In this invention, by designing the arched cross-section as a three-centered circular arch, including a main circular arc 12 and two tangentially connected side circular arcs 13, the beneficial effects of optimized structural stress and improved geometric adaptability are achieved. Compared with a single circular arc arch, the three-centered circular arch has a more uniform stress distribution. The main circular arc 12 bears the main pressure transmission function, while the two side circular arcs 13 play the role of stress transition and boundary adaptation. The tangential connection of the three circular arcs ensures the continuity and smoothness of the entire arch. This geometric design can better adapt to the spatial requirements of the tunnel cross-section, optimizing structural performance while meeting functional requirements, and avoiding the boundary constraint problems and stress concentration phenomena that may occur with a single circular arc.

[0044] Specifically, a three-centered circular arch cross-section refers to an arch structure composed of three circular arcs with different radii, each corresponding to a center. Geometric design ensures these three arcs form a continuous arch curve. A main arc 12, located at the center of the arch, typically has a larger radius and bears the primary load-bearing function. Two tangentially connected side arcs 13, located on either side of the main arc 12, typically have smaller radii and align with the tangent at the connection point, ensuring continuity and a smooth transition. This tangential connection avoids sharp angles and abrupt stress changes, resulting in smoother stress transfer throughout the arch structure.

[0045] In one specific embodiment, when deep-water immersed tunnels are applied to large-span subsea tunnel projects, a single circular arch may be insufficient to simultaneously meet the load-bearing requirements of the central region and the geometric constraints of the boundary regions. A three-centered circular arch cross-section design is adopted, with the main circular arch 12 bearing the main load in the central region. Its larger radius provides excellent load-bearing capacity and space utilization. The two side circular arches 13 act as stress transition points in the boundary regions; their smaller radii better adapt to boundary constraints, avoiding stress concentration at the boundaries. During actual stress transmission, when external water pressure acts on the arch structure, the pressure is first transferred to the main circular arch 12, then smoothly transferred to the two side circular arches 13 through tangential connection points, and finally to the supporting structure. The entire force transmission path is continuous and smooth, avoiding stress abrupt changes and localized damage. This design optimizes material distribution and improves structural efficiency while ensuring structural safety.

[0046] In related technologies, traditional arch designs often employ single circular arcs or parabolic shapes. While these simple geometries are relatively easy to calculate and construct, they often fail to adapt well to the actual conditions of boundary constraints and load distribution under complex engineering conditions. Single circular arc arches are prone to stress concentration at the boundaries, especially at the junctions with straight sections, where stress changes are more drastic and they can easily become weak points in the structure. Although parabolic arches theoretically have better load-bearing performance, their geometry is not conducive to construction control, and their boundary adaptability in actual engineering is poor.

[0047] In this embodiment of the invention, the three-centered circular arch cross-section overcomes the shortcomings of single circular arcs and parabolic arches through the combination of a main circular arc 12 and two side circular arcs 13. The main circular arc 12 provides excellent load-bearing capacity, while the two side circular arcs 13 solve the boundary adaptation problem, and the tangential connection ensures the continuity of the structure. Compared with a single circular arc arch, the three-centered circular arch has a more uniform stress distribution at the boundary, avoiding stress concentration and improving the safety of the structure. Compared with a parabolic arch, the geometry of the three-centered circular arch is easier to control during construction, as each arc has a clear radius and center, facilitating measurement and acceptance. This design achieves a balance between structural performance, construction convenience, and economy, providing a more optimized solution for the arch design of deep-water immersed tunnels.

[0048] In some embodiments, the radius R of the main arc 12 satisfies: 8m≤R≤13m, and the radius r of the side arc 13 satisfies: 1m≤r≤3m.

[0049] In this invention, by setting the radius of the main arc 12 to 8m-13m and the radius of the side arc 13 to 1m-3m, the beneficial effects of optimized configuration of the geometric parameters of the arch structure and precise control of its structural performance are achieved. The radius range of 8m-13m for the main arc 12 ensures sufficient load-bearing capacity and reasonable spatial height in the central area of ​​the arch. Within this radius range, the arch structure can effectively convert external loads into axial pressure for transmission, while providing ample passage space inside the tunnel. The radius range of 1m-3m for the side arc 13 ensures a smooth transition and optimized stress distribution in the arch boundary area. The smaller radius allows the side arc 13 to better adapt to boundary constraints, achieving a gentle stress transfer. This radius ratio achieves the best balance between structural strength, space utilization, and construction feasibility.

[0050] Specifically, the radius of the main arc 12, ranging from 8m to 13m, refers to the arc segments constituting the main arch structure, with their radius controlled within the range of 8 to 13 meters. This radius range was determined considering multiple factors, including the spatial requirements of the deep-water immersed tunnel, structural bearing capacity, and construction conditions. The lower limit of 8 meters ensures sufficient clearance height inside the tunnel to meet basic vehicle traffic requirements; the upper limit of 13 meters considers construction feasibility and economy, as an excessively large radius would increase structural dimensions and construction difficulty. The radius of the side arcs 13, ranging from 1m to 3m, refers to the arc segments located on both sides of the main arc 12, with their radius controlled within the range of 1 to 3 meters. The lower limit of 1 meter ensures that the side arcs 13 have sufficient curvature to achieve a smooth stress transition, while the upper limit of 3 meters ensures geometric compatibility with the main arc 12, avoiding an excessively long transition area that would affect the overall structural efficiency.

[0051] In a specific embodiment, when the deep-water immersed tunnel is designed as a two-way four-lane tunnel, the radius of the main arc 12 is chosen to be 10 meters. This radius ensures sufficient clearance (approximately 6-7 meters) inside the tunnel to meet the passage requirements of large vehicles, while also giving the arch structure good stress performance under external water pressure. The radius of the side arc 13 is chosen to be 2 meters. This radius allows the side arc 13 to smoothly transition from the main arc 12 to the boundary straight section within a length of 3-4 meters, avoiding stress concentration in the transition area and controlling the overall structural dimensions. In actual stress analysis, this radius ratio ensures that when the arch structure is subjected to an external water pressure of 1.0 MPa, the maximum stress occurs in the top region of the main arc 12, and the stress value is controlled within the allowable range of the material. Meanwhile, the stress distribution in the side arc 13 region is uniform, with no obvious stress concentration.

[0052] In related technologies, the selection of the radius for arch structures is often based on experience or simplified calculation methods, lacking in-depth research on the effects of different radius combinations. While an excessively small main arc radius (12) can reduce structural dimensions, it results in an overly sharp arch, easily leading to stress concentration under external loads, and also insufficient internal tunnel space, affecting functionality. Conversely, an excessively large main arc radius (12), while providing ample internal space, increases structural dimensions and material usage, and also results in poor stress transfer at the boundaries. Similar issues exist in selecting the radius of the side arcs (13); an excessively small radius leads to overly abrupt transitions, while an excessively large radius affects the overall structural compactness.

[0053] In this embodiment of the invention, the radius of the main arc 12 is greater than or equal to 8m and less than or equal to 13m, and the radius of the side arc 13 is greater than or equal to 1m and less than or equal to 3m. These are optimized parameters derived from extensive structural analysis and engineering practice. This combination of radii maximizes space utilization and minimizes construction difficulty while ensuring structural strength. Compared to traditional single-radius designs, this dual-radius ratio better adapts to the complex load conditions of deep-water environments, improving structural safety and economy. Compared to empirical radius selection, this parameter setting based on optimization analysis is more scientific and reliable, providing precise technical parameter guidance for the arch design of deep-water immersed tunnels.

[0054] In some embodiments, the steel-concrete composite structure includes: an inner steel panel; an outer steel panel disposed outside the inner steel panel, forming a filling gap between the inner steel panel and the outer steel panel; a connecting component disposed in the filling gap, connecting the inner steel panel and the outer steel panel; and a cast-in-place body filling the filling gap.

[0055] This invention achieves the beneficial effects of optimized material performance and multiple structural functional guarantees through the configuration of a steel-concrete composite structure, including an inner steel panel, an outer steel panel, connecting components, and a cast-in-place body. The inner and outer steel panels form a double-layer steel shell system, providing a continuous tensile skeleton and a complete protective barrier. The filling gap between the inner and outer steel panels provides ideal space for concrete pouring. The connecting components are placed in the filling gap to ensure the coordinated work of the inner and outer steel panels, avoiding possible buckling and relative displacement of the steel plates under external loads. The cast-in-place body fills the filling gap, fully utilizing the compressive strength of the concrete and forming a composite force-bearing system with the inner and outer steel panels, maximizing the utilization of the advantages of both steel and concrete materials.

[0056] Specifically, the inner steel panel refers to the steel plate located inside the structure, directly facing the tunnel's interior space, bearing internal loads and providing internal surface protection. The outer steel panel is located outside the inner steel panel, directly facing the external environment, bearing external load transfer and providing external surface protection. The gap between the inner and outer steel panels is a reserved space between the two layers of steel plates. The size of this space is determined according to structural design requirements, ensuring both the effective thickness of the concrete and ease of construction. Connecting components are located in the gap, connecting the inner and outer steel panels. This involves connecting the inner and outer steel plates into a whole through bolting, welding, or other connection methods, ensuring coordinated deformation of the two layers under stress and preventing relative slippage. The poured material fills the gap, meaning concrete or other pouring materials are filled into the space between the inner and outer steel plates, forming a steel-concrete composite structure.

[0057] In one specific embodiment, when the deep-water immersed tunnel is subjected to an external water pressure of 1.2 MPa, the outer steel panel first bears the water pressure load, transferring the load to the inner steel panel through connecting components. Simultaneously, the cast-in-place structure (self-compacting concrete) bears compressive stress. Under this combined stress state, the steel bears tensile and shear stresses, while the concrete bears compressive stresses, allowing each material to exhibit optimal mechanical properties. The inner steel panel is designed to be 12 mm thick, the outer steel panel to be 15 mm thick, the filling gap width is 300 mm, and the connecting components use shear studs spaced 200 mm apart. Under long-term loads, this composite structure exhibits excellent stability; the steel plates show no buckling, the concrete shows no cracks, and the overall structural deformation is minimal, meeting the stringent requirements of deep-water environments. Furthermore, the double-layered steel plates provide dual protection for the structure; even if the outer steel panel suffers localized damage, the inner steel panel can still ensure the integrity and safety of the structure.

[0058] In related technologies, while traditional reinforced concrete structures possess excellent compressive strength, the discontinuous distribution of reinforcing bars makes them prone to cracking in areas with large rebar spacing, affecting the structural integrity and waterproofing performance. Pure steel structures, although possessing high strength, are susceptible to buckling instability when thick, and steel's corrosion resistance is relatively poor, requiring additional protective measures in marine environments. Traditional steel-concrete composite structures often employ a steel beam + concrete slab configuration, which suffers from uneven stress distribution under surface loads and complex connection structures.

[0059] In this embodiment of the invention, the combined structure of inner and outer double-layer steel panels and a cast-in-place concrete core fully utilizes the advantages of various materials and overcomes the shortcomings of a single material. Compared to traditional reinforced concrete, the double-layer steel panels provide a continuous tensile skeleton, avoiding weak points that may be caused by discontinuous reinforcement. Simultaneously, the steel panels themselves have waterproofing capabilities, improving the reliability of the structure. Compared to pure steel structures, the presence of the cast-in-place concrete core provides lateral support for the steel panels, effectively preventing buckling of the steel plates. Furthermore, the addition of concrete significantly improves the compressive strength and overall stiffness of the structure. Compared to traditional steel-concrete composite structures, this double-sided steel plate + sandwich concrete form results in more uniform stress distribution and more reliable connections, providing a more optimized structural solution for deep-water immersed tunnels.

[0060] In some embodiments, the rigid connection structure 2 includes: a cable mechanism 21 for connecting two adjacent pipe sections 1; a casting layer 22 disposed on the water-facing surface between the two pipe sections 1; and a sealing component 23 disposed on the free surface between the two pipe sections 1.

[0061] In this invention, the rigid connection structure 2, comprising a cable mechanism 21, a cast-in-place layer 22, and a sealing component 23, achieves high strength, high sealing performance, and multiple layers of protection in the connection between pipe sections 1. The cable mechanism 21 provides strong prestressed connection force, ensuring a tight connection between adjacent pipe sections 1 under various working conditions, preventing joint separation and relative displacement. The cast-in-place layer 22, located on the water-facing surface between two pipe sections 1, forms a continuous structural unit, bearing the function of transmitting and dispersing water pressure loads, and also serving as the first waterproof barrier. The sealing component 23, located on the free surface between two pipe sections 1, provides reliable sealing protection, serving as the second waterproof barrier, ensuring that even minor cracks in the cast-in-place layer 22 will not affect the overall waterproof effect. This multi-layered, multi-functional connection system achieves dual optimization of structural and waterproof performance.

[0062] Specifically, the cable mechanism 21 is used to connect two adjacent pipe sections 1. It involves applying prestress between pipe sections 1 using high-strength cable materials such as prestressed steel cables or steel strands, ensuring a tight fit between adjacent sections and forming a unified structure. The working principle of the cable mechanism 21 is to create compressive stress at the joint of the pipe section 1 by tensioning the cables, thus resisting tensile stress from external loads and ensuring a tight connection under various working conditions. The cast-in-place layer 22 is located on the water-facing side between the two pipe sections 1. It involves connecting adjacent pipe sections 1 into a continuous whole by pouring concrete or other materials on-site on the water-facing side. This layer directly bears the external water pressure. The sealing component 23 is located on the air-facing side between the two pipe sections 1. It uses a specialized sealing device on the air-facing side to ensure the sealing performance of the joint and prevent moisture from seeping into the tunnel.

[0063] In one specific embodiment, when the deep-water immersed tunnel is operating at a depth of 100 meters on the seabed, the external water pressure reaches 1.0 MPa. The cable mechanism 21 provides a pre-stress of 1.5 MPa through PC steel strands to ensure that the joint maintains a compressive stress of 0.5 MPa under external water pressure, preventing the joint from opening. The cast-in-place layer 22, made of high-performance concrete with a thickness of 500 mm, directly bears the external water pressure and transfers the load to the pipe section 1 structure, forming a continuous load-bearing system. The sealing component 23 uses a combination of multiple rubber waterstops 232 and sealant, maintaining a good sealing effect even under a water pressure of 0.1 MPa. In actual operation, this triple protection system demonstrates excellent reliability: the cable mechanism 21 ensures the structural connection strength, the cast-in-place layer 22 undertakes the main waterproofing function, and the sealing component 23 provides backup sealing protection. Even under adverse conditions such as earthquakes, temperature changes, and uneven settlement, this connection system can still maintain good working condition.

[0064] In related technologies, the connection of pipe sections in traditional immersed tunnels often adopts flexible connection methods, such as rubber waterstops 232 combined with bolts. Although this connection method can adapt to certain deformations, the connection strength is relatively low, and joints are prone to opening and water leakage under large external loads. A single waterstop 232 seal is prone to aging and failure during long-term use, and once it fails, it is difficult to repair or replace. Traditional rigid connections, while having higher strength, often lack effective sealing measures, making them prone to water leakage at the joints.

[0065] In this embodiment of the invention, the combined connection of the cable mechanism 21, the cast-in-place layer 22, and the sealing component 23 overcomes the shortcomings of traditional connection methods. Compared to flexible connections, this rigid connection has higher connection strength and better overall integrity, and can withstand greater external loads without harmful deformation. Compared to a single sealing method, this multi-seal system provides higher reliability; the cast-in-place layer 22 and the sealing component 23 form double protection, greatly reducing the risk of water seepage. Compared to traditional rigid connections, this connection method fully considers sealing performance while ensuring strength, achieving an organic unity of structural and waterproof functions. This technical solution provides a more reliable and advanced solution for the connection of pipe sections 1 in deep-water immersed tunnels, significantly improving the safety and durability of tunnel engineering.

[0066] In some embodiments, the sealing assembly 23 includes: an end steel shell 231 connected to the end of the pipe section 1, the end steel shell 231 having an abutment portion 2311 that fits against the cast layer 22; a waterstop 232 disposed between the two end steel shells 231, the two ends of the waterstop 232 abutting against the two end steel shells 231 respectively; and a sealing member 233 connecting the two abutment portions 2311; wherein the two abutment portions 2311 and the sealing member 233 form an isolation surface, the isolation surface being used to isolate the cast layer 22 and the sealing assembly 23.

[0067] In this invention, the sealing assembly 23, comprising an end steel shell 231, a waterstop 232, a sealing element 233, and a system configuration forming an isolation surface, achieves the beneficial effects of precise sealing and functional zone protection at the connection point of pipe section 1. The end steel shell 231 connects to the end of pipe section 1 and has an abutment portion 2311 that fits against the cast-in-place layer 22, providing rigid support and precise geometric positioning for the sealing system, ensuring that the sealing assembly 23 can work stably in a predetermined position. The waterstop 232 is positioned between the two end steel shells 231, forming a continuous sealing line through tight contact with the end steel shells 231, preventing moisture penetration along the joint surface. The sealing element 233 connects the two abutment portions 2311, forming an isolation surface together with the abutment portions 2311, effectively isolating the cast-in-place layer 22 and the sealing assembly 23, preventing the cast-in-place layer 22 from affecting the sealing assembly 23 during construction, and providing the sealing assembly 23 with an independent working environment. This multi-layered, multi-functional sealing system achieves a balance between high-precision sealing and long-term reliability.

[0068] Specifically, the waterstop 232 adopts the GINA waterstop 232, and the sealing element 233 adopts an "Ω" shape, with two abutment parts 2311 connected to each end. The connection between the end steel shell 231 and the end of the pipe section 1 refers to the provision of a dedicated steel shell at the end of each pipe section 1, which is connected to the pipe section 1 structure by welding or bolting. The end steel shell 231 serves as the basic component of the sealing system, providing an installation base and support structure for other sealing elements. The end steel shell 231 has abutment parts 2311 that fit against the cast layer 22. This means that the end steel shell 231 is designed with a dedicated boss or groove structure. These structures match the shape of the cast layer 22 to ensure a tight fit between the two, forming a reliable mechanical connection. A waterstop 232 is positioned between two end steel shells 231, with both ends of the waterstop 232 abutting against the two end steel shells 231 respectively. This means that the elastic sealing strip is installed between the end steel shells 231 of two adjacent pipe sections 1, and through elastic deformation, it makes tight contact with the surface of the end steel shells 231, forming a continuous sealing interface. A sealing element 233 connects the two abutting parts 2311, meaning that a special sealing device is installed between the abutting parts 2311 of the two end steel shells 231 to further enhance the sealing effect. The two abutting parts 2311 and the sealing element 233 form an isolation surface used to isolate the cast-in-place layer 22 and the sealing assembly 23. This means that through geometric design, these components form a complete isolation interface, separating the cast-in-place layer 22 on the water-facing side from the sealing assembly 23 on the air-facing side.

[0069] In one specific embodiment, when two sections 1 of the deep-water immersed tunnel are joined, the end steel shell 231 first ensures accurate joining of the two sections 1 through precise geometric positioning. The abutment portion 2311 on the end steel shell 231 fits tightly with the subsequently poured connecting concrete, forming the first sealing interface. The waterstop 232 is made of EPDM rubber, which makes tight contact with the surface of the end steel shell 231 under a compression force of 0.2 MPa, and maintains a good sealing effect even under a water pressure of 0.05 MPa. The sealant 233 is made of polysulfide sealant, forming a continuous sealing layer between the abutment portions 2311, further improving the sealing reliability. The design of the isolation surface makes the water-facing pouring layer 22 and the air-facing sealing component 23 independent of each other. When the pouring layer 22 is subjected to external water pressure, it will not adversely affect the sealing component 23; when the sealing component 23 needs to be repaired, it will not affect the integrity of the pouring layer 22. During long-term operation, this multi-seal system exhibits excellent stability, maintaining good sealing performance even under conditions such as temperature cycling and structural deformation.

[0070] In related technologies, traditional pipe section 1 connection sealing often uses a single waterstop 232 or sealant. While this simple sealing method is convenient to construct, its reliability is relatively low, and it is prone to sealing failure in localized areas. Traditional sealing systems lack effective support structures, and flexible sealing materials such as waterstop 232 are prone to displacement or deformation under external loads, affecting the sealing effect. In traditional designs, the casting layer 22 and sealing components 23 are often mixed together, which can easily damage the sealing material during casting construction and is also inconvenient for later inspection and replacement.

[0071] In this embodiment of the invention, the combined sealing system of the end steel shell 231, waterstop 232, sealing element 233, and isolation surface solves the problems of traditional sealing methods. The end steel shell 231 provides rigid support for the entire sealing system, ensuring that each sealing element works stably in its predetermined position and avoiding displacement problems that may occur with flexible sealing materials. The waterstop 232 and sealing element 233 form a double sealing protection; even if one seal fails, the other seal can still function, greatly improving the reliability of the system. The design of the isolation surface realizes functional zoning; the cast-in-place layer 22 is dedicated to structural functions, and the sealing component 23 is dedicated to sealing functions. The two work independently yet in coordination, ensuring their respective functional effects while facilitating construction and maintenance. This advanced sealing technology provides a reliable guarantee for the long-term safe operation of deep-water immersed tunnels.

[0072] In some embodiments, the cable mechanism 21 includes: a PC cable 211, which is embedded in the end of the pipe section 1; and a connecting sleeve 212, which connects the two PC cables 211.

[0073] In this invention, the cable mechanism 21 includes a PC cable 211 pre-embedded at the end of pipe section 1 and a connecting sleeve 212 connecting the two PC cables 211, achieving the beneficial effects of high-strength prestressed connection between pipe sections 1 and convenient construction. The PC cable 211 is pre-embedded at the end of pipe section 1, completing installation during the pipe section 1 manufacturing stage, avoiding complex on-site construction operations, and ensuring reliable anchoring of the cable to the pipe section 1 structure. The PC cable 211 uses high-strength prestressed steel, capable of withstanding large tensile forces, providing strong pre-compression for the connection of pipe sections 1. The connecting sleeve 212, as the connecting component between the two PC cables 211, enables rapid on-site connection. Through the tensioning and anchoring mechanism inside the sleeve, the two independent PC cables 211 are connected into a continuous cable system, making adjacent pipe sections 1 form an integral structure. This pre-embedded connection method combined with rapid on-site connection technology achieves a dual improvement in construction efficiency and connection quality.

[0074] Specifically, the pre-embedded PC cable 211 at the end of pipe section 1 refers to the pre-installation of prestressed concrete steel strands or wire bundles in pre-drilled holes or grooves at the end of pipe section 1 during its manufacturing process. This allows for reliable connection to the pipe section 1 structure via anchors or chemical anchoring. The pre-embedded position of the PC cable 211 is precisely calculated to ensure that the cable axis aligns with the direction of the connecting force, maximizing the connection effect. The connecting sleeve 212 connects two PC cables 211. At the pipe section 1 docking site, a specially designed sleeve device connects the PC cables 211 of two adjacent pipe sections 1. The connecting sleeve 212 typically contains a tensioning device and an anchoring device, which can apply a predetermined tension force to the PC cable 211 and anchor the cable within the sleeve after reaching the design stress, forming a reliable connection.

[0075] In one specific embodiment, when two deep-water immersed tunnel sections 1 need to be connected, each section 1 has 12 pre-embedded PC steel strands with a diameter of 15.2mm at its end. The strength grade of the steel strands is 1860MPa, and the design tension of a single steel strand is 200kN. The connecting sleeve 212 is made of high-strength steel, is 1.5m long, and has an inner diameter slightly larger than the diameter of the PC steel strands. Anchors are installed at both ends of the sleeve. During on-site connection, the two sections 1 are first precisely aligned, and then the connecting sleeve 212 is fitted onto the alignment of the two PC steel strands. Prestress is applied to the steel strands through the tensioning device in the center of the sleeve. When the tension reaches the design value, the steel strands are anchored to both ends of the sleeve through the anchors, completing the connection. The entire connection process is completed within 4 hours. The connected cable system can provide a total preload of 2400kN to the joint of section 1, ensuring that the joint remains tightly connected under various working conditions. This connection method is simple to construct, has controllable quality, and greatly improves the construction efficiency in deep-water environments.

[0076] In related technologies, traditional pipe section connections often employ on-site steel reinforcement welding or bolt connections. These methods are difficult to implement in deep-water environments, and quality is hard to guarantee. On-site steel reinforcement welding requires underwater operations, which is not only difficult to perform but also highly susceptible to environmental influences, making welding defects common. While bolt connections are relatively simple, their connection strength is limited and cannot meet the requirements of high-pressure deep-water environments. Traditional prestressed connections often require on-site threading and tensioning of steel strands, a complex operation that is difficult to implement in deep-water environments.

[0077] In this embodiment of the invention, the connection method of pre-embedded PC cable 211 + connecting sleeve 212 fully considers the special characteristics of deep-water environment and construction convenience. Compared with on-site welding, this mechanical connection method is not affected by ambient temperature and humidity, ensuring stable and reliable connection quality and avoiding defects that may occur during welding. Compared with bolted connections, the PC cable 211 connection provides greater connection strength, meeting the stringent requirements of deep-water high-pressure environments. Compared with traditional prestressed connections, pre-embedded installation avoids the complex operation of on-site cable threading, and the connecting sleeve 212 enables rapid connection, greatly simplifying the construction process. This connection technology not only ensures high strength and high reliability of the connection but also significantly improves construction efficiency in deep-water environments, providing an advanced connection solution for deep-water immersed tunnel engineering.

[0078] In some embodiments, the water-facing surface of pipe section 1 is coated with glass flake paint; and / or, the air-facing surface of pipe section 1 is coated with epoxy zinc-rich primer.

[0079] In this invention, by applying glass flake paint to the water-facing side of pipe section 1 and / or applying epoxy zinc-rich primer to the free-face side, the beneficial effects of comprehensive anti-corrosion protection and differentiated protection strategies for the steel structure are achieved. The glass flake paint, applied to the water-facing side, directly faces corrosive media such as seawater. The sheet-like structure of the glass flakes forms a multi-layered barrier within the coating, effectively preventing the penetration of corrosive media into the steel substrate. Simultaneously, the glass flakes possess excellent chemical corrosion resistance, enabling long-term resistance to chloride ion erosion in seawater. The epoxy zinc-rich primer, applied to the free-face side, uses zinc powder as a sacrificial anode in the coating, providing electrochemical protection to the steel substrate. Even if localized damage occurs in the coating, the cathodic protection of zinc still prevents steel corrosion. This differentiated anti-corrosion strategy, tailored to different environmental conditions, achieves a balance between maximizing anti-corrosion effectiveness and optimizing costs.

[0080] Specifically, the water-facing surface of pipe section 1 is coated with glass flake paint. This refers to the application of an anti-corrosion coating containing glass flake filler to the surfaces of pipe section 1 that directly contact seawater or other corrosive water bodies. Glass flakes are thin sheets of glass, 2-5 micrometers thick and 10-500 micrometers in diameter, arranged in an overlapping, fish-scale pattern within the coating, forming a multi-layered barrier structure. When corrosive media attempt to penetrate the coating, they must bypass the overlapping glass flakes, significantly extending the penetration path and effectively preventing corrosion. The air-facing surface of pipe section 1 is coated with an epoxy zinc-rich primer. This refers to the application of an epoxy primer containing a high concentration of zinc powder to the air-facing surfaces of pipe section 1. The zinc powder content typically reaches over 85%, forming a conductive network within the coating and giving it electrochemical activity. When the steel substrate comes into contact with zinc, the zinc acts as the anode and is preferentially corroded, thus protecting the steel substrate from corrosion.

[0081] In one specific embodiment, the deep-water immersed tunnel is continuously submerged in seawater with a salinity of 3.5%, where the chloride ion concentration reaches as high as 19,000 mg / L, posing a strong corrosive effect on the steel structure. The water-facing surface is coated with a 250-micron thick glass flake paint containing 30% glass flakes. These glass flakes form a dense barrier structure, reducing the chloride ion permeability coefficient to less than 1 / 10 of that of ordinary coatings. After 20 years of immersion testing, the glass flake paint coating still maintains excellent anti-corrosion performance, with no obvious signs of corrosion on the steel substrate. The air-facing surface is coated with a 75-micron thick epoxy zinc-rich primer containing 90% zinc powder, providing strong cathodic protection for the steel substrate. In a simulated marine atmospheric environment, even if the coating is scratched and exposes the steel substrate, the steel can still remain corrosion-free for more than 10 years under the cathodic protection of zinc. This differentiated anti-corrosion strategy selects the most suitable anti-corrosion coating based on the characteristics of the corrosive environment of different parts, achieving the optimal balance between anti-corrosion effect and economy.

[0082] In related technologies, traditional steel structure corrosion protection often employs a uniform coating scheme, which cannot effectively adapt to the varying corrosive environments of different locations. While single anti-corrosion coatings are easy to apply, they often cannot simultaneously meet the corrosion protection requirements of different environments. This results in either excessive anti-corrosion performance leading to cost waste, or insufficient anti-corrosion performance affecting service life. Traditional anti-corrosion coatings mostly use organic coatings, which, while possessing good decorative properties, are prone to aging and failure in harsh marine environments, requiring frequent maintenance.

[0083] In this embodiment of the invention, the combined application of glass flake paint and epoxy zinc-rich primer fully considers the complexity of the deep-water environment. Compared to a uniform coating scheme, this differentiated anti-corrosion strategy can select the most suitable anti-corrosion coating for the specific corrosion conditions of different parts, maximizing the anti-corrosion effect. Glass flake paint has superior shielding performance and durability compared to traditional organic coatings, making it particularly suitable for use in areas that are in direct contact with corrosive media. Epoxy zinc-rich primer, compared to ordinary anti-corrosion coatings, not only provides shielding but also electrochemical protection, maintaining its anti-corrosion function even when the coating is damaged. This advanced anti-corrosion technology provides reliable anti-corrosion protection for the long-term safe operation of deep-water immersed tunnels, significantly extending the service life of the structure and reducing maintenance costs.

[0084] In some embodiments, pipe section 1 is provided with a sacrificial anode.

[0085] In this invention, by arranging sacrificial anodes in pipe section 1, the beneficial effects of active electrochemical corrosion protection and long-term maintenance-free protection of the steel structure are achieved. The sacrificial anodes are made of reactive metals such as zinc, aluminum, and magnesium. When forming an electric couple with the steel structure, the sacrificial anode, acting as the anode, preferentially corrodes, while the steel structure, acting as the cathode, is protected. This electrochemical protection mechanism is active and continuous, independent of external power sources; the protective effect continues as long as the sacrificial anode material is present. The arrangement design of the sacrificial anodes considers current distribution and protection range, ensuring that the entire pipe section 1 structure is within the effective protection potential range. This active corrosion protection technology is particularly suitable for deep-sea marine environments, effectively resisting the corrosive effects of chloride ions in seawater and providing long-term reliable corrosion protection for the steel structure.

[0086] Specifically, pipe section 1 is equipped with sacrificial anodes. These are anode blocks made of reactive metal installed at appropriate locations within the pipe section 1 structure. These anode blocks are connected to the steel structure of pipe section 1 via wires or direct contact, forming a galvanic cell. The material selection for the sacrificial anodes is determined based on the protected object and environmental conditions. Commonly used materials include zinc alloys, aluminum alloys, and magnesium alloys. The number and placement of the sacrificial anodes are calculated based on factors such as the geometry of pipe section 1, the distribution of the steel structure, and the resistivity of seawater, ensuring that the potential of the entire surface of pipe section 1 meets the protection standard. The working principle of the sacrificial anodes is based on the theory of electrochemical corrosion. When two metals with different potentials are connected in an electrolyte, the metal with the lower potential will act as the anode and undergo an oxidation reaction, while the metal with the higher potential will act as the cathode and be protected.

[0087] In one specific embodiment, the natural potential of deep-water immersed tunnel segment 1 in seawater is approximately -0.65V (relative to a saturated calomel electrode). To achieve effective protection, the potential needs to be polarized to below -0.85V. A zinc-aluminum-cadmium alloy sacrificial anode is used, with an anode potential of -1.05V, providing a driving voltage of 0.4V. Based on the surface area and protective current density of segment 1, 20 sacrificial anodes, each weighing 50kg, are required for each segment 1, for a total anode weight of 1000kg. These anodes are evenly distributed on the water-facing side of segment 1 and connected to the steel shell of segment 1 via welded steel connecting plates. Under the condition that the resistivity of seawater is 0.25Ω·m, the sacrificial anode system can provide the designed protective current for segment 1, keeping the surface potential of the entire segment 1 below -0.85V. Based on the anode consumption rate, these sacrificial anodes can provide effective protection for more than 30 years, meeting the design service life requirements of the tunnel. In actual operation, regular potential monitoring shows that the surface potential of segment 1 remains stable within the protection range, and there is no corrosion of the steel structure.

[0088] In this embodiment of the invention, the sacrificial anode protection system overcomes the shortcomings of traditional corrosion protection methods. Compared to passive coating protection, the sacrificial anode provides active electrochemical protection, maintaining its protective function even when the coating is damaged, thus significantly improving the reliability of corrosion protection. Compared to impressed current protection, the sacrificial anode does not require an external power source, making the system simple and reliable, and particularly suitable for use in environments that are difficult to maintain, such as deep water. The sacrificial anode has a long service life, providing decades of effective protection with a single installation, greatly reducing maintenance costs and difficulties. This active corrosion protection technology, together with the anti-corrosion coating, forms a dual protection system, providing more comprehensive and reliable corrosion protection for the steel structure of deep-water immersed tunnels, ensuring the long-term safe operation of the tunnel project.

[0089] like Figure 6 As shown, this utility model provides a construction method for the above-mentioned deep-water immersed tunnel structure, including the following steps: S1, Pipe Section 1 Manufacturing: Pipe section 1, which is a steel-concrete composite structure, is manufactured. The top plate 11 of pipe section 1 adopts an arched cross section. S2, Pipe section 1 installation: Transport pipe section 1 to the construction location and place it in place; S3. Rigid connection: The two adjacent pipe sections 1 are connected by cables and post-cast concrete.

[0090] This invention achieves the benefits of systematization, standardization, and high efficiency in the construction of deep-water immersed tunnel structures through a construction method comprising three main steps: pipe section 1 manufacturing, pipe section 1 installation, and rigid connection. The pipe section 1 manufacturing step ensures that the steel-concrete composite structure pipe section 1 is manufactured in a controlled factory environment, guaranteeing manufacturing quality and geometric accuracy. The precise shaping of the arched cross-section provides a foundation for subsequent installation and connection. The pipe section 1 installation step transports the prefabricated pipe section 1 to the construction location and precisely places it in place. This process requires overcoming the complex conditions of the deep-water environment, such as the influence of ocean currents, waves, and visibility. The rigid connection step uses cables and post-cast concrete to connect adjacent pipe sections 1, linking independent pipe section 1 units into a continuous tunnel structure, forming an integral load-bearing system. This step-by-step construction method decomposes the complex deep-water tunnel project into controllable construction units, improving construction efficiency and project quality.

[0091] Specifically, the manufacturing of segment 1 refers to the production of the steel-concrete composite structure segment 1 at a specialized manufacturing base, according to design requirements. The manufacturing process includes steel shell processing, concrete pouring, curing, and quality inspection. A key geometric requirement is the arched cross-section of the top plate 11 of segment 1, which requires precise templates and strict quality control. Segment 1 installation involves transporting the manufactured segment 1 from the manufacturing base to the tunnel construction site and then using specialized sinking equipment to lower it into the designated position. This process requires precise positioning and attitude control to ensure accurate alignment between segment 1 and adjacent segments. Rigid connection refers to connecting adjacent segments into a unified structure after segment 1 is installed in place, using cable tensioning and subsequent concrete pouring. The cables provide prestressed connection, and the poured concrete forms a continuous structure; both work together to achieve a rigid connection.

[0092] In this embodiment of the invention, the systematic construction method fully considers the characteristics and requirements of deep-water immersed tunnel engineering. Compared to traditional on-site manufacturing, factory-manufacturing of the tunnel section 1 can be carried out in a controlled environment, ensuring manufacturing quality and efficiency, especially the precise shaping of complex geometries such as arched cross-sections. Compared to traditional on-site connection, the increased prefabrication and standardized connection process greatly simplify on-site operations and improve the safety and reliability of construction in deep-water environments. Compared to traditional experience-based construction, this construction method based on scientific analysis and practical verification has stronger adaptability and repeatability, providing mature and reliable construction technology for deep-water immersed tunnel engineering and promoting the standardization and industrialization of this type of engineering technology.

[0093] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A rigidly connected immersed tunnel structure for deep water up to 100 meters deep, characterized in that, include: Pipe section (1), the pipe section (1) adopts a steel shell concrete composite structure, and the top plate (11) of the pipe section (1) adopts an arched cross section; A rigid connection structure (2) is disposed between two adjacent pipe sections (1) for connecting the two pipe sections (1) in the extension direction. The top plate (11) includes: a crane hole top plate (111), which has a circular arch cross section; and a pipe gallery top plate (112), which is disposed between the two crane hole top plates (111) and has a flat plate structure.

2. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 1, characterized in that, The arched cross section is a three-centered circular arched cross section, including a main circular arc (12) and two side circular arcs (13) tangentially connected to it.

3. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 2, characterized in that, The radius R of the main arc (12) satisfies: 8m≤R≤13m, and the radius r of the side arc (13) satisfies: 1m≤r≤3m.

4. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 1, characterized in that, The steel-concrete composite structure includes: Inner steel panel; An outer steel panel is disposed on the outside of the inner steel panel, and a filling gap is formed between the inner steel panel and the outer steel panel; A connecting component, disposed in the filling gap, connects the inner steel panel and the outer steel panel; The casting body is filled into the filling gap.

5. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 1, characterized in that, The rigid connection structure (2) includes: A cable mechanism (21) is used to connect two adjacent pipe sections (1); A pouring layer (22) is provided on the water-facing side between the two pipe sections (1); A sealing assembly (23) is disposed on the free surface between the two pipe sections (1).

6. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 5, characterized in that, The sealing assembly (23) includes: The end steel shell (231) is connected to the end of the pipe section (1), and the end steel shell (231) has an abutment portion (2311) that fits against the casting layer (22). A waterstop (232) is disposed between the two end steel shells (231), and the two ends of the waterstop (232) abut against the two end steel shells (231) respectively; A sealing element (233) connects the two abutment portions (2311). The two abutment portions (2311) and the seal (233) form an isolation surface, which is used to isolate the cast layer (22) and the sealing assembly (23).

7. The 100-meter-class deep-water rigid connection immersed tunnel structure according to claim 5, characterized in that, The cable mechanism (21) includes: PC cable (211) is pre-embedded at the end of the pipe section (1); Connecting sleeve (212) connects the two PC cables (211).

8. The 100-meter-class deep-water rigid connection immersed tunnel structure according to any one of claims 1-7, characterized in that, The tube section (1) is equipped with a sacrificial anode.

9. The 100-meter-class deep-water rigid connection immersed tunnel structure according to any one of claims 1-7, characterized in that, The water-facing surfaces of the pipe section (1) are all coated with glass flake paint; And / or, the free surface of the pipe section (1) is coated with an epoxy zinc-rich primer.

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