A combined underwater suspended tunnel

Abstract

The present invention discloses a combined underwater suspended tunnel, which comprises multiple tunnel pipe bodies connected to each other. The structures of the multiple tunnel pipe bodies include two or three of the following structures: pressure-bearing pier column pipe bodies, cable anchor pipe bodies, and buoy pipe bodies. A GINA waterstop is provided at the tail end of each pipe body. Adjacent pipe bodies are connected end to end, and a connection structure is provided at the connection part. The connection structure includes two connection ear plates respectively arranged on the outer circumferential surfaces at both ends of each pipe body. Two connection prestressed steel cables are tensioned between adjacent pipe bodies through the two pairs of connection ear plates, and a flexible waterproof sleeve is welded at the outer circumferential surface of the connection end of the two pipe bodies. The structures of the multiple tunnel pipe bodies of the underwater suspended tunnel are determined according to the sea conditions defined by international standards. The number of pipe sections of each type of structure is determined according to the offshore distance within the water depth range of the sea area where the suspended tunnel is constructed and the length of a single pipe section. The present invention simultaneously achieves the purposes of adapting to complex waters, adapting to navigation areas, and reducing costs.

Description

Technical Field

[0001] The invention belongs to the technical field of cross-sea channel engineering, and specifically relates to a combined underwater suspended tunnel and an installation method. Background Art

[0002] In order to promote national economic growth and promote regional coordinated development, how to quickly and safely cross rivers, lakes and seas is a key issue in transportation construction. At present, bridges are still the main form of spanning structures, but due to their high requirements for the terrain on both sides, bridges cannot be used in some steep places. As an emerging spanning structure, immersed tube tunnels are greatly affected by sea conditions and seismic loads, and are easily damaged, making it impossible to pass through waters with complex sea conditions and frequent earthquakes. Submerged Floating Tunnel (SFT) is a new type of spanning transportation building, which mainly solves the problem of human beings crossing deep water and wide waters in the future. The particularity of its structure can also effectively avoid the effect of seismic loads and is suitable for passage in complex sea conditions. The floating tunnel can be suspended in the water by reasonably designing the deadweight of the pipe section, relying on its buoyancy in the water and the constraints of the support system. Since the floating tunnel is completely immersed in water, it is less affected by harsh natural environments such as typhoons, heavy snow, and dense fog, and will not affect the navigation of ships. It can ensure safe and stable traffic efficiency and minimize the impact of construction on the ecological environment.

[0003] Underwater suspended tunnels are divided into three categories according to different anchoring methods: pressure-bearing pier-type suspended tunnels, anchor-cable suspended tunnels, and pontoon-type suspended tunnels. Among them, the pressure-bearing pier-type suspended tunnel is suitable for shallow waters (within 50m). Since the pressure-bearing piers are used as supporting structures, it has good stability, but with the increase of water depth, the construction difficulty is huge. The anchor-cable suspended tunnel is suitable for medium water depths (50m-200m) and can adapt to waters with frequent earthquakes and poor seabed conditions. However, when facing severe sea conditions with strong winds and waves, the overall stability of the tunnel is poor and it is easy to induce vibration. The pontoon-type suspended tunnel is suitable for deep water (above 200m). With the increase of water depth, the construction and operation and maintenance costs change little, which is very economical. However, when facing severe sea conditions with strong winds and waves, the pontoon will be greatly affected, causing a large lateral displacement to the tunnel. Since the existence of the pontoon structure will affect the passage of ships, the pontoon-type suspended tunnel cannot be used in maritime navigation areas. At present, the design of floating tunnels is single-form and only applicable to relatively simple sea conditions. It cannot meet the requirements of deep water, wide water area, and crossing navigation areas, and faces the problems of difficult construction and high construction costs. At present, there is no complete technical process for the installation of floating tunnels, and most of them refer to the installation method of immersed tube tunnels for reference. However, the installation method of immersed tube tunnels is highly dependent on the laying of the seabed and is not suitable for the floating installation of combined floating tunnels. Summary of the Invention

[0004] In view of the above-mentioned prior art, the present invention provides a combined underwater suspended tunnel. For some areas with complex water environments, large tunnel spans, and significant differences in offshore water depths and geological conditions, the combined suspended tunnel can effectively integrate the advantages of various tunnel forms, has strong adaptability to the environmental waters, is applicable to areas with large tunnel spans, significant differences in offshore water depths and geological conditions, and can reduce the construction difficulty and construction cost. Thus, the purpose of adapting to complex waters, adapting to navigable areas, and reducing costs can be achieved.

[0005] To solve the above technical problems, the present invention provides a combined underwater suspended tunnel, which includes multiple connected tunnel pipe bodies. The structures of the multiple tunnel pipe bodies include two or three of the structures of pressure-bearing pier column pipe bodies, cable anchor pipe bodies, and floating barrel pipe bodies; a GINA waterstop is provided at the tail end of each pipe body, and adjacent pipe bodies are connected end to end, and a connection structure is provided at the connection end to end. The connection structure includes two connection ear plates respectively arranged on the outer circumferential surfaces at both ends of each pipe body. Two connection prestressed steel cables are tensioned between adjacent pipe bodies through the two pairs of connection ear plates, and a flexible waterproof sleeve is connected at the outer circumferential surface of the connection end of the two pipe bodies; the structure of the multiple tunnel pipe bodies of the underwater suspended tunnel is determined according to the sea conditions defined by international standards; the length of a single pipe section of each structural pipe body is 200 m; the number of pipe sections of each structural pipe body is determined according to the offshore distance and the length of a single pipe section within the water depth range of the sea area where the suspended tunnel is built.

[0006] Furthermore, for the combined underwater suspended tunnel of the present invention, among them:

[0007] Regarding the pressure-bearing pier column pipe body, the construction of the pressure-bearing pier column is carried out with reference to the port engineering pile foundation specification (JYJ245-98), and both ends of the pipe body passing through the pressure-bearing pier column are respectively at least 1 m longer than the side surface of the pressure-bearing pier column.

[0008] The two connection ear plates arranged on the outer circumferential surfaces at both ends of each pipe body are distributed at 180° in the circumferential direction; the radial distance between the through holes on the two connection ear plates is greater than the outer diameter of the flexible waterproof sleeve, and the flexible waterproof sleeve is composed of two half hoop clamps. The axial dimension of the flexible waterproof sleeve is greater than the width of the GINA waterstop and less than the axial distance between the two connection ear plates on adjacent two pipe bodies.

[0009] The process of connecting two adjacent pipe sections using the said connection structure is as follows: After fixing the two pipe sections in end-to-end butt joint, the connection prestressed steel cable between the two pipe sections is tightened by a jack to reach the prestress. During the tightening process, the GINA waterstop is compressed to achieve watertightness at the connection of adjacent pipe sections. Then, two semi-ring hoops are welded in a clasped shape on the outer circumferential surface at the butt joint of adjacent pipe sections to achieve overall reinforcement and sealing.

[0010] The said sea conditions include different ranges of offshore water depths, seabed conditions, and whether seismic activities are frequent under the annual average sea condition grade. Based on the above sea conditions, the types of structures included in multiple tunnel pipe sections and their layout positions are as follows:

[0011] Case 1: The annual average sea condition grade is 1 - 3, including:

[0012] 1 - 1) The offshore water depth is within 50m, and the seabed condition is soft clay foundation or hard rock foundation. If seismic activities are frequent, the structure of the multiple tunnel pipe sections is the cable - anchor section pipe; if seismic activities are not frequent, the structure of the multiple tunnel pipe sections is the bearing pier column section pipe.

[0013] 1 - 2) The offshore water depth is between 50m and 200m, and the seabed condition is soft clay foundation or hard rock foundation. Regardless of whether seismic activities are frequent, the structure of the multiple tunnel pipe sections is the cable - anchor section pipe.

[0014] 1 - 3) The offshore water depth is above 200m, and the seabed condition is soft clay foundation or hard rock foundation. Regardless of whether seismic activities are frequent, the structure of the multiple tunnel pipe sections is the floating cylinder section pipe.

[0015] Case 2: The annual average sea condition grade is 3 - 6, including:

[0016] 2 - 1) The offshore water depth is within 50m, and the seabed condition is soft clay foundation or hard rock foundation. If seismic activities are frequent, the structure of the multiple tunnel pipe sections is the cable - anchor section pipe; if seismic activities are not frequent, the structure of the multiple tunnel pipe sections is the bearing pier column section pipe.

[0017] 2 - 2) The offshore water depth is between 50m and 200m, and the seabed condition is soft clay foundation or hard rock foundation. Regardless of whether seismic activities are frequent, the structure of the multiple tunnel pipe sections is the cable - anchor section pipe.

[0018] 2 - 3) The offshore water depth is above 200m, and the seabed condition is soft clay foundation or hard rock foundation. If seismic activities are frequent, the structure of the multiple tunnel pipe sections is the floating cylinder section pipe; if seismic activities are not frequent, the structure of the multiple tunnel pipe sections is the cable - anchor section pipe.

[0019] Case 3: The annual average sea condition grade is 6 - 9, including:

[0020] 3-1) When the offshore water depth is within 50m, the seabed condition is a soft clay foundation or a hard rock reef foundation; if seismic activities are frequent, the structure of the multi-section tunnel pipe body is the cable anchor section pipe body, and if seismic activities are not frequent, the structure of the multi-section tunnel pipe body is the bearing pier column section pipe body;

[0021] 3-2) When the offshore water depth is between 50m and 200m, if the seabed condition is a soft clay foundation and regardless of whether seismic activities are frequent or not, the structure of the multi-section tunnel pipe body is the cable anchor section pipe body; if the seabed condition is a hard rock reef foundation and regardless of whether seismic activities are frequent or not, the structure of the multi-section tunnel pipe body is the bearing pier column section pipe body;

[0022] 3-3) When the offshore water depth is above 200m, if the seabed condition is a soft clay foundation or a hard rock reef foundation and regardless of whether seismic activities are frequent or not, the structure of the multi-section tunnel pipe body is the cable anchor section pipe body.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] By combining various structural forms of the floating tunnel, the construction of the floating tunnel is applicable to a more complex water environment, reducing the construction difficulty and construction cost, and making the floating tunnel have stronger applicability and a broader popularization and application prospect. In shallow water areas (within 50m), the water depth is convenient for construction and maintenance. Selecting the bearing pier column section pipe body has good stability and can provide longitudinal stiffness for the pipe sections in deep water areas. When the wind and waves come, the lateral displacement of the tunnel pipe body can be minimized as much as possible. In medium water depth areas (50m - 200m) or waters with frequent earthquakes and poor seabed conditions, selecting the cable anchor section pipe body, the seismic load directly acting on the tunnel structure can be buffered via the cable anchor. Compared with traditional traffic structures, it can better buffer, perform and dampen vibrations. At the same time, the water area reserved above the pipe body can be used as a shipping channel for ships, which is conducive to the three-dimensional utilization of marine space. In deep water areas (above 200m), selecting the floating drum section pipe body can effectively reduce the construction and operation and maintenance costs that increase steeply with the water depth. And because some floating drum section pipe bodies are selected, the overall motion performance and stability are higher than those of a floating tunnel with a single design. And when some pipe sections are damaged, due to the different tunnel forms, a chain reaction of continuous damage to the entire tunnel will not occur. The various structural forms of the floating tunnel are applicable to waters with large water depth changes and large spans. It has good motion performance and stability while having a low cost. The structural forms are flexible for different water areas to overcome the technical difficulties of installation and operation and maintenance, and have good practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the combined underwater floating tunnel of the present invention;

[0026] Figure 2 is Figure 1Axial view of the shown combined underwater suspended tunnel;

[0027] Figure 3 is Figure 1 End view of the shown combined underwater suspended tunnel;

[0028] Figure 4 Is the enlarged partial detail drawing of the butt joint of the suspended tunnel pipe segment;

[0029] Figure 5 Is the schematic diagram of the transportation and installation of the pressure-bearing pier column pipe body and the pontoon pipe body;

[0030] Figure 6 Is the schematic diagram of the transportation and installation of the cable anchor pipe body;

[0031] Figure 7-1 、 Figure 7-2 、 Figure 7-3 、 Figure 7-4 Are the schematic diagrams of the design schemes of four embodiments in the present invention.

[0032] In the figure:

[0033] 1 - Pressure-bearing pier column pipe body 2 - Cable anchor pipe body 3 - Pontoon pipe body

[0034] 4 - Flexible waterproof sleeve 5 - Pressure-bearing pier 6 - Several diagonal ropes

[0035] 7 - Saddle 8 - Cable anchor seat 9 - Mooring cable anchor

[0036] 10 - Anchoring foundation 11 - Pontoon 12 - Pontoon mooring rope

[0037] 13 - GINA waterstop 14 - Connecting prestressed steel cable 15 - High-strength fiber cable

[0038] 16 - Pipe body circular buckle 17 - Arc-shaped installation pontoon 18 - Water inlet

[0039] 19 - Water outlet 20 - Hydraulic drainage device 21 - Underwater positioning and signal transmission device

[0040] 22 - Rectangular installation pontoon Detailed implementation manners

[0041] The following further describes the present invention in conjunction with the accompanying drawings and specific embodiments, but the following embodiments are by no means any limitation to the present invention.

[0042] As Figure 1 、 Figure 2 and Figure 3As shown in the figure, a combined underwater suspension tunnel proposed by the present invention includes multiple tunnel pipe bodies connected to each other. The structures of the multiple tunnel pipe bodies include two or three of the following structures: a bearing pier column section pipe body 1, a cable anchor section pipe body 2, and a buoy section pipe body 3.

[0043] In waters with shallow sea areas and relatively flat seabeds and good soil quality, the bearing pier column section pipe body 1 can be adopted. The bearing pier column section pipe body 1 is supported and fixed by bearing piers 5 and several diagonal cables 6. Both the bearing pier column section pipe body 1 and the bearing pier columns 5 are made of cast concrete. Bearing piers 5 are added at certain intervals to provide longitudinal and lateral stability for the suspension tunnel. Several diagonal cables 6 are prestressed and are connected from the bearing pier column section pipe body 1 to the sides of the bearing pier columns 5. The bearing pier column section pipe body 1 is made of a material with a density greater than that of water. The through-type bearing pier 5 provides support for the pipe body and enhances the structural stability of the overall tunnel. The diagonal cables 6 on both sides of the bearing pier 5 improve the stability of the entire pipe body, reduce the swaying of the pipe body, and allow internal vehicles to pass smoothly. In the present invention, for the bearing pier 5, the construction of the bearing pier columns is carried out with reference to the port engineering pile foundation specification JYJ245 - 98. The two ends of the pipe body passing through the bearing pier columns are each at least 1 m longer than the sides of the bearing pier columns, as Figure 1 and Figure 2 shown.

[0044] In medium-depth waters with strong currents and more severe sea conditions, the cable anchor section pipe body 2 can be adopted. The cable anchor section pipe body 2 is fixed by a saddle 7, a cable anchor seat 8, a mooring cable 9, and an anchoring foundation 10. The pipe body is made of cast concrete in segments. Anchoring foundations 10 are provided on the seabed at certain intervals. The tops of several mooring cables 9 are connected to the cable anchor seats 8 of the saddle 7 fixed on the top of the pipe body, and the bottoms are connected to the supporting anchoring foundations 10, and prestress is applied in advance. The cable anchor section pipe body 2 is made of a material with a density less than that of water. The saddle 7 is provided at the top of the pipe body. The saddle 7 is made of stainless steel and welded into a U-shaped anchoring steel bar inserted into the underwater suspension tunnel pipe body. The size of the saddle 7 should be determined according to the size of the anchoring tension cable force and the safety factor to select the thickness of the cable anchor diameter. There is a cable anchor seat 8 at the connection between the saddle 7 and the mooring cable 9. The bottom of the cable anchor seat 8 is connected to the cable anchor section pipe body 2 through embedded anchor bolts. After the mooring cable 9 is fixed on the cable anchor 7 seat, corresponding protective measures are taken to treat the connection, and then it is sealed with a sealing cover; the other end of the mooring cable 9 is connected to the anchoring foundation 10. During the construction process, one end of the mooring cable 9 is first installed on the anchoring foundation 10, and then the other end of the mooring cable 9 passes through the cable anchor seat 8, and the mooring cable 9 is tensioned to the design cable force with a jack and then fixed.

[0045] In areas with deep water, gentle water flow, few wave floes, and low navigation volume, the floating pontoon section pipe body 3 can be adopted. The floating pontoon section pipe body 3 is formed by segmented casting of concrete. Floats 11 are provided at certain intervals. One end of a number of floating pontoon mooring ropes 12 is connected to the float 11, and the other end is connected to the floating pontoon section pipe body 3. A material with a density greater than that of water is selected to manufacture the floating pontoon section pipe body 3. The float 11 floats on the water surface and is connected to the floating pontoon section pipe body 3 through the matching floating pontoon mooring rope 12, so that the tunnel floats and remains stable. To prevent the structure from being corroded by the marine environment, the surface of the float 11 is coated with a polyurethane anti-corrosion coating.

[0046] At the tail end of each pipe body, a GINA waterstop 13 is provided. Adjacent two pipe bodies are connected end to end, and a connection structure is provided at the connection part. The connection structure includes two connection ear plates respectively arranged on the outer circumferential surfaces at both ends of each pipe body. Between adjacent pipe bodies, two connection prestressed steel cables 14 are tightened through the two pairs of connection ear plates. The connection prestressed steel cables 14 are used to tighten the pipe bodies at both ends to achieve flexible connection of the two pipe bodies, so that the floating tunnel has better movement performance. At the outer circumferential surface of the connection end of the two pipe bodies, a flexible waterproof sleeve 4 is provided. The flexible waterproof sleeve 4 is an annular metal-rubber composite plate, with a stainless steel plate as the base material, and is connected in multiple sections with rubber gaskets. Both the inner and outer sides are coated with a polyurethane anti-corrosion coating and are subjected to sealing and waterproof treatment to realize the axial compression of the flexible waterproof sleeve 4, and play a secondary protection role for the connection part of different pipe bodies. The GINA waterstop 13 is used for watertight treatment to prevent seawater from flowing in. In the present invention, in the connection structure provided at the connection part of the heads and tails of adjacent two pipe bodies, the two connection ear plates arranged on the outer circumferential surfaces at both ends of each pipe body are distributed at 180° in the circumferential direction; the radial distance between the through holes on the two connection ear plates is greater than the outer diameter of the flexible waterproof sleeve 4.

[0047] The flexible waterproof sleeve 4 is used for the connection between floating tunnels of different pipe sections. In the embodiment of the present invention, the flexible waterproof sleeve 4 is a circular steel pipe, and its size fits the floating tunnel pipe body. For the convenience of installation, the flexible waterproof sleeve 4 is composed of two semi-ring hoops in a hugging shape. The axial dimension of the flexible waterproof sleeve 4 is greater than the width of the GINA waterstop 13 and less than the axial distance between the two connection ear plates on adjacent two pipe bodies. As Figure 3 and Figure 4As shown in the figure, the process of connecting two adjacent pipe sections using the connection structure is as follows: After fixing the two pipe sections in end-to-end docking, the connection prestressed steel cable 14 between the two pipe sections is tightened by a jack to reach the prestress. During the tightening process, the GINA waterstop is compressed to achieve watertightness at the connection between adjacent pipe sections. After welding the two semi-ring hoops together in a clasped shape, they are fixed to the outer surfaces of the two adjacent pipe sections by spot welding on both sides of the flexible waterproof sleeve 4. When the connection prestressed steel cable 14 needs to be re-tightened during use, the flexible waterproof sleeve 4 can be axially compressed to provide secondary protection for the internal GINA waterstop 13.

[0048] Determine the structure of multiple tunnel pipe sections of the underwater suspended tunnel according to the sea conditions defined by international standards; the sea conditions include different offshore water depth ranges, seabed conditions, and whether the area is earthquake-prone under the annual average sea condition level; determine the types of structures included in the multiple tunnel pipe sections and their layout positions according to the above sea conditions, as shown in Table 1.

[0049] Table 1. Forms of combined suspended tunnels and corresponding sea conditions

[0050]

[0051]

[0052] On the premise of determining the pipe section structure shown in Table 1, further consider the sea area span of the suspended tunnel, the offshore distance of the water depth range, and the length of a single pipe joint, so as to determine the overall structure of the combined underwater suspended tunnel. In the present invention, the length of a single pipe joint of each type of structure is 200 m.

[0053] Example 1

[0054] The span is 15 km, the annual average sea condition level within a water depth of 50 m is 1 - 3, the distances from both sides to the shore are 5 km each, the seabed is a hard rock foundation and there is no earthquake; the annual average sea condition within the water depth range of 50 m - 100 m is 3 - 6, the distances from both sides to the shore are 10 km, and the seabed is a hard rock foundation without earthquake; for the above sea conditions, the multiple tunnel pipe sections of this Example 1 include 50 pressure-bearing pier column pipe sections and 25 cable anchor pipe sections. The connection sequence of all pipe sections is 25 pressure-bearing pier column pipe sections - 25 cable anchor pipe sections - 25 pressure-bearing pier column pipe sections, as Figure 7-1 shown.

[0055] Example 2

[0056] When the span is 15 km, the average annual sea condition level within a water depth of 50 m is level 1 - 3, the distance from both sides to the shore is 5 km, the seabed is a hard rock foundation and there is no earthquake; when the span is 15 km, where the water depth exceeds 50 m, the water depth increases steeply and is greater than 200 m, the average sea condition in the area is level 3 - 6, the distance from both sides to the shore is 10 km, the seabed is a hard rock foundation and there is no earthquake; for the above sea conditions, the multi - section tunnel pipe body of this Embodiment 2 includes 50 pressure - bearing pier column pipe bodies and 25 floating cylinder pipe bodies, and the connection sequence of all pipe bodies is 25 pressure - bearing pier column pipe bodies - 25 floating cylinder pipe bodies - 25 pressure - bearing pier column pipe bodies; as Figure 7-2 shown.

[0057] Embodiment 3,

[0058] When the span is 30 km, the average annual sea condition level within a water depth of 50 m is level 1 - 3, the distance from both sides to the shore is 5 km, the seabed is a hard rock foundation and there is no earthquake; when the water depth is 50 m - 200 m, the average annual sea condition level is level 1 - 3, the distance from both sides to the shore is 10 km, the seabed is a hard rock foundation and earthquakes occur frequently; when the water depth exceeds 200 m, the average annual sea condition level is level 3 - 6, the distance from both sides to the shore is 15 km, the seabed is a hard rock foundation and earthquakes occur frequently; for the above sea conditions, the multi - section tunnel pipe body of this Embodiment 3 includes 50 pressure - bearing pier column pipe bodies, 50 cable anchor section pipe bodies and 50 floating cylinder pipe bodies, and the connection sequence of all pipe bodies is 25 pressure - bearing pier column pipe bodies - 25 floating cylinder pipe bodies - 50 cable anchor section pipe bodies - 25 floating cylinder pipe bodies - 25 pressure - bearing pier column pipe bodies; as Figure 7-3 shown.

[0059] Embodiment 4,

[0060] When the span is 20 km, the average annual sea condition level within a water depth of 50 m is level 1 - 3, the distance from one side to the shore is 2 km, the seabed is a hard rock foundation and there is no earthquake, the distance from the other side to the shore is 10 km, the seabed is a hard rock foundation and there is no earthquake; where the water depth exceeds 50 m, the water depth increases steeply and is greater than 200 m, the average annual sea condition level is level 3 - 6, the distance from one side to the shore is 10 km, the seabed is a hard rock foundation and earthquakes occur frequently; when the water depth is 50 m - 200 m, it gradually becomes shallower, the average annual sea condition level is level 3 - 6, the distance from one side to the shore is 15 km, the seabed is a hard rock foundation and earthquakes occur frequently; for the above sea conditions, the multi - section tunnel pipe body in this Embodiment 4 includes 35 pressure - bearing pier column pipe bodies, 25 cable anchor section pipe bodies and 40 floating cylinder pipe bodies, and the connection sequence of all pipe bodies is: 10 pressure - bearing pier column pipe bodies - 40 floating cylinder pipe bodies - 25 cable anchor section pipe bodies - 25 pressure - bearing pier column pipe bodies, as Figure 7-4 shown.

[0061] Embodiment 5

[0062] If the tunnel span is greater than 3000m, the construction of a combined floating tunnel should be considered, and the structural design should be carried out according to the design ideas shown in Table 1. In this embodiment, a device for transporting the pipe body (but not limited to this device) is proposed, which mainly includes an arc-shaped installation buoy 17 and a rectangular installation buoy 22. The arc-shaped installation buoy 17 is used to transport the pressure pier column section pipe body 1 and the buoy section pipe body 3. The pipe body is transported to the designated position by means of a towing installation ship. The side of the arc-shaped installation buoy 17 is provided with a water inlet 18, the bottom is provided with a water outlet 19, and a hydraulic drainage device 20 is arranged inside. The pipe body is controlled to sink to the designated depth through the water inlet 18, and the arc-shaped installation buoy 17 is lifted through the water outlet 19 and the hydraulic drainage device 20. This arc-shaped installation buoy can be reused repeatedly. The rectangular installation buoy 22 is used to transport the anchor cable section pipe body 2. The pipe body is transported to the designated position by means of a towing installation ship. The working principle of the rectangular installation buoy 22 is basically the same as that of the arc-shaped installation buoy 17, and it can control the pipe body to sink and realize its own multiple uses. As Figure 5 , Figure 6 shown.

[0063] And the installation is carried out according to the following steps:

[0064] Step 1: First, complete the division of the pipe body form and combination selected for the sea area where the floating tunnel is built according to the following standards. The length of the pipe section of the combined floating tunnel is 200m. Determine the structure of the multi-section tunnel pipe body of the underwater floating tunnel according to factors such as the sea conditions defined by international standards, the change of the water depth from the shore in the design area, the seabed foundation conditions, and whether it is an earthquake-prone area.

[0065] Determine the number of such pipe sections according to the offshore distance within the water depth range and the length of a single pipe section. Y1 and Y2 in Table 2 both represent the pressure pier column section pipe body; M, M1, and M2 all represent the anchor cable section pipe body; F represents the buoy section pipe body. Table 2 shows the pipe body structure form combinations of the entire floating tunnel in Embodiments 1 to 4.

[0066] Table 2. Combinations of Floating Tunnels in Embodiments 1-4

[0067]

[0068]

[0069] Step 2: Complete the construction of each type of pipe section in the dry dock. The construction of the pressure-bearing pier column pipe section 1 and the pontoon pipe section 3 can be carried out synchronously. First, complete the erection of the internal steel bars of the pipe section in the dry dock, and fabricate multiple outer concrete pouring molds according to the steel bars. Calculate the density of the required concrete based on the buoyancy and gravity of the pipe section. The two can be poured with the same formulated concrete, and this process is consistent with the pipe section construction process in the immersed tube tunnel design code (GB / T 51318-2019). Install the fixed pipe ring buckle 16 at intervals of 10 m at the tops of the pressure-bearing pier column pipe section 1 and the pontoon pipe section 3, and install the arc-shaped installation pontoon 17 at the bottom of the pipe section through a crane. The high-strength composite fiber cable 15 fixes the arc-shaped installation pontoon 17 and the pressure-bearing pier column pipe section 1 through the pipe ring buckle 16. For the construction of the cable anchor pipe section 2, it needs to be carried out separately. Complete the erection of the internal steel bars of the pipe section in the dry dock, and fabricate multiple outer concrete pouring molds according to the steel bars. Select lightweight aggregate concrete for formulation, and its density should ensure that the buoyancy of the pipe section is greater than the gravity. After the pipe section construction is completed, install the saddle 7 at the center position of the pipe section, and connect the arc-shaped installation pontoon 17 and the saddle 7 with high-strength fiber cables 15. Install the pipe ring buckle 16 at intervals of 10 m on both sides of the saddle 7.

[0070] Step 3: Install the GINA waterstop 13 at the tail end of each pipe section, and use steel doors to seal the two sides of the pipe body for water, completing the first outfitting. Fill the dry dock with water until the pipe body floats completely. Drag the installation workboat into the dry dock, and install the general underwater positioning device and signal receiving device 21 on both sides of the pipe body. Install the connecting ear plates required for connecting the prestressed steel cables 14 by bolts at the central axis positions of the pipe wall symmetrically up and down at both ends of the pipe body, and connect the required steel cables at the tail end. Complete the second outfitting of the pipe body.

[0071] Step 4: For Embodiment 1, the following method should be used for installation. First, transport the pressure-bearing pier column pipe section 1 to the designated location by dragging the installation workboat. The underwater installation boat connects the pipe ring buckle 16 with the working crane on the ship deck through the high-strength fiber cable 15. The structural form when the pressure-bearing pier column pipe section 1 is connected to the crane during the installation process is as Figure 5As shown in the figure. Open the water inlet 18 of the bottom arc-shaped mounting buoy 17 to gradually lower the pipe body. Through the signal feedback display of the underwater positioning and signal transmission device 21, when it descends to the specified depth, close the water inlet 18 of the arc-shaped mounting buoy 17, and use the robotic arm of the crane to complete the horizontal docking of the pipe section. The diving staff disconnects the high-strength fiber cable 15 between the pressure-bearing pier column pipe body 1 and the arc-shaped mounting buoy 17, and opens the water outlet 19 to drain the internal seawater through the hydraulic device 20 to achieve the floating and secondary utilization of the buoy. After fixing the pipe sections on both sides, tighten the connecting prestressed steel cables 14 on the pipe wall with a jack to reach the prestress. During the process, compress the GINA waterstop 13 at the end of the pipe section to complete the watertight treatment of the connection, and then use the flexible waterproof sleeve 4 for overall reinforcement and sealing. The construction of the pressure-bearing pier column is carried out with reference to the pile foundation specifications of port engineering (JYJ245-98). The length of the pipe body passing through the pressure-bearing pier column is relatively short, and each side extends 1 m beyond to be connected to the next pipe section. After completing the installation of the pressure-bearing pier column pipe bodies 1 on both sides, carry out the transportation and installation of the cable anchor section pipe body 2. Drag the installation workboat to be directly connected to the saddle 7 of the cable anchor section pipe body 2 and transport it to the specified location. The underwater installation boat connects the pipe body annular bayonet 16 to the working crane on the ship deck through the high-strength fiber cable 15. The structural form during the connection of the cable anchor section pipe body 2 to the crane during the installation process is as Figure 6 shown in the figure. Open the water inlets 18 of the rectangular mounting buoys 22 connected to the saddle 7 simultaneously to gradually lower the pipe body. Through the signal feedback display of the underwater positioning and signal transmission device 21, when it descends to the specified depth, close the water inlets 19 of the rectangular mounting buoys 22 on both sides, and use the robotic arm of the crane to complete the horizontal docking of the pipe section. The diving staff disconnects the high-strength fiber cable 15 between the saddle 7 and the rectangular mounting buoy 22, and opens the water outlet 19 to drain the internal seawater through the internal hydraulic device 20, and the rectangular mounting buoy 22 floats up. After fixing the pipe sections on both sides, tighten the connecting prestressed steel cables 14 on the pipe wall with a jack to reach the prestress. During the process, compress the GINA waterstop 13 at the end of the pipe section to complete the watertight treatment of the connection, and then use the flexible waterproof sleeve 4 for overall reinforcement and sealing. The connecting prestressed steel cable at the connection between the cable anchor section pipe body 2 and the pressure-bearing pier column pipe body 1 should be slightly less than the tension of the connection of the same type of pipe body. The width dimension of the GINA waterstop 13 is slightly larger than the width dimension of the waterstop at the tail during the connection of the same type of pipe body. The width of the flexible waterproof sleeve 4 should be twice the width of the joint at the connection of the same type of pipe body (generally, the width of the joint at the connection of the same type of pipe body is 0.5 m) to ensure flexible connection, allow a certain displacement, and prevent damage to the connection. The installation sequence is Y1 - Y2 - M.

[0072] For Example 2, the following installation method should be adopted. First, the installation method of the pressure-bearing pier column section of the pipe body 1 is the same as that of Example 1. After the installation of the pressure-bearing pier column section of the pipe body 1 is completed, the installation of the floating cylinder section of the pipe body 3 is carried out. First, the floating cylinder section of the pipe body 3 is transported to the designated location by dragging the installation workboat. The floating cylinder mooring cable 12 is installed on the water surface and connected to the floating cylinder 11. The underwater installation ship connects the pipe body annular bayonet 16 to the working crane on the ship deck through the high-strength fiber cable 15. The structural form when the floating cylinder section of the pipe body 3 is connected to the crane during the installation process is as Figure 5 shown. The water inlet of the bottom arc-shaped installation floating cylinder 17 is opened to gradually lower the pipe body. Through the signal feedback display of the underwater positioning and signal transmission device 21, when it reaches the designated depth, the water inlet 18 of the arc-shaped installation floating cylinder 17 is closed. The diving staff disconnects the high-strength fiber cable 15 between the pipe body annular buckle 16 and the arc-shaped installation floating cylinder 17, opens the water outlet 19, discharges the internal seawater through the internal hydraulic device 20, and the arc-shaped installation floating cylinder 17 floats. The pre-tension of the mechanical arm of the crane is reduced until the floating cylinder section of the pipe body 3 remains stable. The length of the floating cylinder mooring cable 13 is adjusted by the jack until the floating cylinder section of the pipe body 3 reaches the designated installation position, and the mechanical arm of the crane is used to complete the horizontal docking of the pipe section. After fixing the pipe sections on both sides, the connecting prestressed steel cable 14 on the pipe wall is tightened by the jack to reach the pre-tension. During the process, the GINA waterstop 13 at the end of the pipe section is compressed to complete the watertight treatment of the connection, and then the flexible waterproof sleeve 4 is used for overall reinforcement and sealing. The installation sequence is Y1—Y2—F.

[0073] For Example 3, the following installation method should be adopted. First, the installation methods of the pressure-bearing pier column section of the pipe body 1 and the cable anchor section of the pipe body 2 are the same as those of Example 1. The installation method of the floating cylinder section of the pipe body 3 is the same as that of Example 2. At the connection between the cable anchor section of the pipe body 2 and the floating cylinder section of the pipe body 3, the lateral displacement generated is larger than that of Example 2. Therefore, the tension of the connecting prestressed steel cable 4 at the connection between the cable anchor section of the pipe body 2 and the floating cylinder section of the pipe body 3 should be slightly less than the tension of the pipe section at the connection between the cable anchor section of the pipe body 2 and the pressure-bearing pier column section of the pipe body 1 in Example 2. The size of the GINA waterstop 13 is slightly larger than that of the GINA waterstop 13 at the connection between the cable anchor section of the pipe body 2 and the pressure-bearing pier column section of the pipe body 1 in Example 2. The width of the flexible waterproof sleeve 4 should be four times that of the same pipe section joint to ensure sufficient flexible connection and watertightness and prevent damage to the connection. The installation sequence is Y1—Y2—M1—M2—F.

[0074] For Example 4, the following installation method should be adopted. The installation methods of the pressure-bearing pier column section of the pipe body 1 and the cable anchor section of the pipe body 2 are the same as those of Example 1. The installation method of the floating cylinder section of the pipe body 3 of the pressure-bearing pier column section of the pipe body 1 is the same as that of Example 2. The installation method of the connection part is the same as that of Example 2 and Example 3. The installation sequence is Y1—Y2—M—F.

[0075] Step Five: After the installation of the pipe section is completed, remove the annular buckle 16 of the installation equipment body and the underwater positioning and signal transmission device 21, and complete the watertightness detection. After ensuring that no water enters the inside of the pipe body connection, the staff enters the inside of the pipe body to remove the waterproof steel door installed during the first outfitting of the pipe body, and perform secondary concrete filling and pouring on the highway connection inside the pipe section to ensure the continuous flatness of the road surface. After completing the internal primary and secondary electrical design, the road can be opened to traffic.

[0076] Although the present invention has been described above in conjunction with the accompanying drawings, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many variations without departing from the purpose of the present invention, and all of these fall within the protection scope of the present invention.

Claims

1. A combined underwater suspended tunnel, comprising a plurality of tunnel tubes connected to each other, characterized in that, The structure of the multi-section tunnel tube body includes two or three of the following structures: the pressure-bearing pier column section tube body (1), the cable anchor section tube body (2), and the floating cylinder section tube body (3); At the tail end of each section of the tube body, a GINA water stop (13) is provided. Adjacent sections of the tube body are connected end to end, and a connecting structure is provided at the connection. The connecting structure includes two connecting ear plates respectively arranged on the outer circumferential surfaces at both ends of each section of the tube body. Between adjacent tube bodies, two connecting prestressed steel cables (14) are tensioned through the two pairs of connecting ear plates, and a flexible waterproof sleeve (4) is provided at the outer circumferential surface of the connection end of the two sections of the tube body; Determine the structure of the multi-section tunnel tube body of the underwater suspended tunnel according to the sea conditions defined by international standards; the length of a single pipe section of each type of tube body structure is 200m; the number of sections of each type of tube body structure is determined according to the offshore distance and the length of a single pipe section within the water depth range of the sea area where the suspended tunnel is built; The sea conditions include different offshore water depth ranges, seabed conditions, and whether seismic activities are frequent under the annual average sea condition level; according to the above sea conditions, determine the types of structures included in the multi-section tunnel tube body and their layout positions, and there are the following situations: Situation 1: The annual average sea condition level is 1-3 levels: 1-1) The offshore water depth is within 50m, and the seabed condition is soft clay foundation or hard rock foundation; if seismic activities are frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; if seismic activities are not frequent, the structure of the multi-section tunnel tube body is the pressure-bearing pier column section tube body; 1-2) The offshore water depth is between 50m and 200m, and the seabed condition is soft clay foundation or hard rock foundation, and regardless of whether seismic activities are frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; 1-3) The offshore water depth is above 200m, and the seabed condition is soft clay foundation or hard rock foundation, and regardless of whether seismic activities are frequent, the structure of the multi-section tunnel tube body is the floating cylinder section tube body; Situation 2: The annual average sea condition level is 3-6 levels, excluding level 3: 2-1) The offshore water depth is within 50m, and the seabed condition is soft clay foundation or hard rock foundation; if seismic activities are frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; if seismic activities are not frequent, the structure of the multi-section tunnel tube body is the pressure-bearing pier column section tube body; 2-2) The offshore water depth is between 50m and 200m, and the seabed condition is soft clay foundation or hard rock foundation, and regardless of whether seismic activities are frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; 2-3) The offshore water depth is above 200m, and the seabed condition is soft clay foundation or hard rock foundation; if seismic activities are frequent, the structure of the multi-section tunnel tube body is the floating cylinder section tube body; if seismic activities are not frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; Situation 3: The annual average sea condition level is 6-9 levels, excluding level 6: 3-1) The offshore water depth is within 50m, and the seabed condition is soft clay foundation or hard rock foundation; if seismic activities are frequent, the structure of the multi-section tunnel tube body is the cable anchor section tube body; if seismic activities are not frequent, the structure of the multi-section tunnel tube body is the pressure-bearing pier column section tube body; 3-2) When the offshore water depth is between 50m and 200m, if the seabed condition is soft clay foundation and regardless of whether the earthquake is frequent or not, the structure of the multi-section tunnel pipe body is the cable anchor section pipe body; if the seabed condition is hard rock foundation and regardless of whether the earthquake is frequent or not, the structure of the multi-section tunnel pipe body is the press pier column section pipe body; 3-3) When the offshore water depth is above 200m, if the seabed condition is soft clay foundation or hard rock foundation and regardless of whether the earthquake is frequent or not, the structure of the multi-section tunnel pipe body is the cable anchor section pipe body.

2. The combined underwater suspended tunnel according to claim 1, wherein For the said press pier column section pipe body (1), the construction of the press pier column is carried out with reference to the port engineering pile foundation specification JYJ245-98, and both ends of the pipe body passing through the press pier column are respectively at least 1m longer than the side surface of the press pier column.

3. The combined underwater suspended tunnel according to claim 1, characterized in that, The two connecting ear plates arranged on the outer circumferential surfaces at both ends of each pipe section are distributed circumferentially at 180°; the radial distance between the through holes on the two connecting ear plates is greater than the outer diameter of the flexible waterproof sleeve (4), and the flexible waterproof sleeve (4) is composed of two semi-ring hoops in a clasped state. The axial dimension of the flexible waterproof sleeve (4) is greater than the width of the GINA waterstop (13) and less than the axial distance between the two connecting ear plates on the adjacent two pipe sections.

4. The combined underwater suspended tunnel according to claim 3, characterized in that, The process of connecting adjacent two pipe sections by using the said connecting structure is as follows: after fixing the two pipe sections in head-to-tail butt joint, the connecting prestressed steel cable (14) between the two pipe sections is tightened by a jack to reach the pre-tension. During the tightening process, the water tightness at the connection of adjacent pipe sections is realized by compressing the GINA waterstop. Then, the two semi-ring hoops are welded in a clasped state on the outer circumferential surface at the butt joint of the adjacent pipe sections to realize the overall reinforcement and sealing.

Images