A method for connecting a submerged tube to a floating box and a floating box used in the method
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- MUNICIPAL ENVIRONMENTAL PROTECTION ENG CO LTD OF CREC SHANGHAI GRP
- Filing Date
- 2026-03-06
- Publication Date
- 2026-06-09
Smart Images
Figure CN122165080A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of immersed tunnel construction, and in particular to a method for underwater docking of immersed tunnels and a floating box used therein. Background Technology
[0002] During immersed tunnel construction, multiple steel pipe sections are typically welded together on land or water. However, due to site limitations, there is often not enough space to fabricate the entire immersed tunnel. Therefore, in practice, the entire immersed tunnel is often divided into multiple sections for welding, depending on the actual conditions of the construction site on land or water. These sections are then floated to open water and joined together on the water to form a whole.
[0003] Currently, common immersed tunnel docking technologies are mainly divided into two categories: onshore docking technologies and offshore docking technologies. Onshore docking technologies include traditional segmented welding technologies and long pipeline splicing and water entry technologies; offshore docking technologies mainly include offshore welding operation platform technologies and steel pipeline offshore docking platform technologies.
[0004] Traditional segmented welding technology involves welding steel pipe sections together on shore before launching the entire section into the water. This technology offers advantages such as favorable onshore welding conditions and high welding quality, but it also has significant drawbacks: for long-distance immersed pipes, multiple launches in multiple segments are required, leading to poorer onshore connection quality and higher risks associated with mechanical lifting operations. The long-pipeline splicing and launching technology utilizes a pipeline splicing platform built on the shore. Multiple pipe sections are hoisted and placed on the assembly and welding station for construction. Finally, high tide allows the pipe sections to roll freely along the launching platform to the surface. While this technology improves connection efficiency and precision, its adaptability to complex water conditions still needs improvement.
[0005] In terms of underwater docking technology, the traditional method of launching steel pipes in multiple sections requires the use of a floating crane to lift the two pairs of pipe ends out of the water for welding. This process is greatly affected by wind, waves, and lifting operations, making it difficult to guarantee the docking and welding quality. In addition, adjacent pipe ends cannot be worked on simultaneously during docking and welding, otherwise it will affect the construction quality of the pipe ends being docked, resulting in low overall construction efficiency.
[0006] Traditional positioning methods (such as dual-tower positioning systems) use a water surface baseline as a reference. In deep water areas, the measuring towers are prone to tilting due to water flow disturbances and wave impacts, leading to baseline vector instability. Simultaneously, delays in the transmission and processing of measurement data prevent real-time feedback on pipe segment attitude changes, causing accumulated positioning errors and severely impacting docking accuracy. Furthermore, insufficient coordination between measurement and construction is also a contributing factor to difficulties in accuracy control.
[0007] Existing technologies have high requirements for site conditions and sea conditions. For example, the splicing and submersion technology of long pipelines has specific requirements for the flatness and slope of the site; while existing splicing platforms and launching platforms are mostly fixed designs, which cannot be flexibly adjusted according to different shoreline topography, thus limiting the applicability of the technology. Most engineering sites have complex shoreline topography, and temporary site modifications are costly and time-consuming. At the same time, the design of the offshore welding operation platform and the steel pipeline docking platform does not fully consider the impact of complex hydrological and meteorological conditions, resulting in insufficient resistance to environmental interference and difficulty in ensuring stability under harsh sea conditions.
[0008] In summary, developing a immersed tube docking technology and equipment that can improve the quality of underwater docking and welding, enable simultaneous operation of multiple tube ports, enhance docking accuracy under deep water and complex hydrological conditions, and has stronger environmental adaptability is a pressing technical problem that needs to be solved. Summary of the Invention
[0009] The purpose of this invention is to provide an efficient underwater docking technology for immersed tubes, while ensuring waterproofing measures for underwater docking and improving welding quality.
[0010] To achieve the above objectives, this invention proposes a method for underwater docking of immersed tubes, comprising the following steps: Step S1: Install limiting plates and mating plates on each of the two interfaces of the immersed tube to be docked, and weld blind plates to both ends of the immersed tube; float the immersed tube to be docked to the docking water area for preliminary docking, so that the mating plates on both sides are inserted into the opposite pipe openings, and then pull the two interfaces of the immersed tube to be docked to a weldable distance by passing through the limiting plates on both sides with a tie rod. Step S2: Use a crane vessel to lift the pontoon to the interface of the immersed tube to be docked, so that the pontoon's plate clamps fit into the outer wall of the immersed tube to be docked, and set a water-stopping component between the plate clamps and the outer wall to form a closed space; then pump out the water accumulated in the pontoon's sump. Step S3: Weld the interface of the immersed tube to be docked. After welding, enter the tube through the manhole reserved on the immersed tube to be docked, remove the blind plate and the docking plate, and finally seal the manhole. Step S4: Fill the pontoon with water, loosen the plate clamps to disconnect the pontoon from the immersed tube to be docked, use a crane vessel to lift the pontoon away and float it to the next docking point, and repeat the above steps.
[0011] Optionally, in step S1: the initial docking is achieved by using a tugboat or floating crane to assist in inserting the staggered docking plates at both ends of the docking pipe into the opposite pipe openings.
[0012] Optionally, the pull rod is a threaded pull rod, and nuts are provided on the inner and outer sides of each limiting plate. The welding spacing is controlled by tightening the inner and outer nuts to the required position.
[0013] Optionally, in step S2: the water-stopping component is a water-swellable water-stopping strip, which is pasted on the outer wall of the pontoon's plate hoop that contacts the submerged pipe; the pontoon includes an upper semi-circular plate hoop and a lower semi-circular plate hoop. During installation, the lower plate hoop is first hoisted to fit against the lower half of the outer pipe wall of the submerged pipe and the water-stopping component is set, and then the upper plate hoop is installed. The upper and lower plate hoops are connected by bolts to form a complete clamping structure.
[0014] Optionally, the bottom of the pontoon is provided with a sandwich layer, so that when the water in the pontoon's sump is pumped out, the water in the sandwich layer is retained to resist the buoyancy of the pontoon's bottom plate.
[0015] Optionally, in step S4, the pontoon removal includes: first filling the pontoon with water to the full capacity to increase sinking stability or eliminate buoyancy interference, then loosening the plate clamps, and finally being lifted away by a crane vessel; after the pontoon is removed, it is configured to be reusable and move to the next immersed tube docking interface.
[0016] In addition, the present invention also proposes a floating box for underwater docking of immersed tubes, comprising: The enclosure is made of sheet metal and includes a bottom plate, side plates, and a top plate. The plate hoop includes an upper semi-circular plate hoop and a lower semi-circular plate hoop, wherein the lower semi-circular plate hoop is recessed into the top plate of the box body. The interlayer includes an interlayer plate connected inside the side panel of the box body, with water collection pits provided at the four corners of the interlayer plate, and the interlayer plate is arranged opposite to the bottom plate.
[0017] Optionally, the interlayer includes channel steel disposed on the base plate, the channel steel being arranged in a cross pattern to form a load-bearing frame, the top of the load-bearing frame being provided with the interlayer plate, and the height between the interlayer plate and the base plate being between 400 and 500 mm.
[0018] Optionally, the plate hoop is provided with a water-stopping component.
[0019] This invention improves the efficiency of underwater docking of immersed tubes. By constructing underwater docking pontoons, a dry working environment for underwater docking of immersed tubes is achieved, ensuring the quality of welding, corrosion prevention, and other processes. The underwater docking pontoons are fixedly connected to the pipeline via clamps, enabling simultaneous underwater docking of multiple sections of immersed tubes. The docking process is simple and fast, improving construction efficiency. This rapid underwater docking technology for steel pipes has a simple structure and is easy to operate. Compared with renting large areas of land to fabricate the entire immersed tube on shore or setting up an underwater tunnel fabrication platform, it has lower costs, less environmental impact, and significant economic and social benefits. Attached Figure Description
[0020] Figure 1This is a front view of the underwater docking of the immersed tube. Figure 2 This is a side view of the underwater docking of the immersed tube. Figure 3 This is a top view of the underwater docking of the immersed tunnel sections. Figure 4 This is a schematic diagram of the bottom plate of the pontoon box; Figure 5 Schematic diagram of the pontoon sandwich panel; Figure 6 This is a schematic diagram of the external tie rod and the corresponding support plate. Detailed Implementation
[0021] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for underwater docking of immersed tubes and the floating box used therein, based on the present invention. The advantages and features of the present invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, intended only to facilitate and clearly illustrate the embodiments of the present invention. Please refer to the accompanying drawings to make the objectives, features, and advantages of the present invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes to aid those skilled in the art and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the present invention, should still fall within the scope of the technical content disclosed in the present invention.
[0022] The underwater docking of the immersed tubes proposed in this invention is achieved using a floating box 2, such as... Figures 1 to 6 As shown, the floating box 2 includes a box body composed of a bottom plate, side plates, and a top plate, all of which are made of steel plates 3. A plate hoop 6 is provided on the top plate, comprising an upper semi-circular plate hoop and a lower semi-circular plate hoop, with the lower semi-circular plate hoop recessed into the top plate of the box body. The plate hoop is used to fix the immersed tube 1 to be docked. A mezzanine is provided within the box body for water storage. The mezzanine is composed of a mezzanine plate connected inside the side plates, also made of steel plates 3, and is positioned opposite the bottom plate. Water collection pits 16 are provided at the four corners of the mezzanine plate, through which water can be extracted or drained from the mezzanine. Water in the mezzanine can be retained to resist the buoyancy of the floating box bottom plate.
[0023] The buoy also includes a frame composed of channel steel 4 and angle steel 5 connected longitudinally and transversely, with steel plates 3 attached to the frame. Specifically, the bottom plate and side plates are welded from steel plates 3. The inside of the steel plates 3 is reinforced with channel steel 4 in a "well" shape, and the "well" shaped channel steel 4 is reinforced with angle steel 5 by oblique welding. The sandwich panel, composed of steel plates 3 and channel steel 4, is located inside the buoy and is about 400-500mm higher than the bottom plate of the buoy. First, a "well" shaped load-bearing frame is welded to the lower part of the sandwich panel using channel steel 4, then the steel plates 3 are laid and welded to the side plates. At the same time, holes are left at the corners of the steel plates 3 as water collection pits 16. A semi-circular plate hoop 6 is welded to the top plate where the buoy contacts the immersed tube. The semi-circular plate hoop 6 is reinforced with plate hoop stiffening ribs 7 between it and the top plate of the buoy. A water-swellable waterstop strip 8 is installed between the semi-circular plate hoop 6 and the contact surface of the immersed tube for sealing. The upper part of the docking pontoon is provided with a semi-circular plate hoop 6, and two pontoon fixing bolts 9 are provided on the contact surface of the upper and lower semi-circular plate hoops to fix the pontoon after the installation is completed.
[0024] The pipes to be docked, also known as steel pipes, are initially docked and then transferred to the pontoon 2, where they are secured by clamps 6. Limiting plates 11 are installed at the joints of the steel pipes 1 to secure the tie rods 10. Reinforcing ribs 12 are welded between the limiting plates 11 and the wall of the steel pipes 1 to increase strength. Alignment plates 13 are welded inside the pipe openings, and blind flanges 14 are welded to both ends of each steel pipe to temporarily seal the pipes, facilitating the pontoon's movement to a specific water area. The blind flanges 14 are generally located inside the alignment plates. Manholes 15 are also provided on the steel pipes for personnel to enter after welding and remove the blind flanges and alignment plates. The tie rods are threaded, with inner nuts 18 and outer nuts 17 threaded onto them. The inner nuts are located inside the two opposing limiting plates 11, and the outer nuts are located outside the two opposing limiting plates. The outer nut is used to control the maximum distance the two interfaces are pulled close together during the initial docking to meet welding requirements; the inner nut is used to limit the minimum distance the two interfaces are pulled close together during the initial docking to ensure proper weld spacing. The mating plates of the two steel pipes to be docked are staggered to facilitate insertion into the opposite pipe openings.
[0025] The underwater docking construction method for immersed tubes proposed in this invention includes the following steps: Step S1: Install limiting plates and mating plates on each of the two interfaces of the immersed tube to be docked, and weld blind plates to both ends of the immersed tube; float the immersed tube to be docked to the docking water area for preliminary docking, so that the mating plates on both sides are inserted into the opposite pipe openings, and then pull the two interfaces of the immersed tube to be docked to a weldable distance by passing through the limiting plates on both sides with a tie rod. Step S2: Using a crane vessel, the pontoon is lifted to the interface of the immersed tube to be connected, so that the pontoon's clamps fit against the outer wall of the immersed tube, and a water-stopping component is installed between the clamps and the outer wall to form a closed space; then, the water in the pontoon's sump is pumped out. Water in the interlayer can be retained to resist the buoyancy of the pontoon's bottom plate. The crane vessel's hook is released, and the floating crane vessel moves to the next interface to repeat the steps, achieving synchronous connection of multiple immersed tube sections.
[0026] Step S3: Weld the interface of the immersed tube to be docked. After welding, enter the tube through the pre-reserved manhole to remove the blind flange and the mating plate, and finally seal the manhole. The interface needs to be thoroughly cleaned before welding. Since the pontoon can be accessed after pumping water, operators can enter the pontoon to inspect the interface and perform anti-corrosion work. After welding, enter the tube through the pre-reserved manhole to remove the blind flange, mating plate, and other devices, and apply anti-corrosion material.
[0027] Step S4: Fill the pontoon with water, loosen the plate clamps to disconnect the pontoon from the immersed tube to be docked, use a crane vessel to lift the pontoon away and float it to the next docking point, and repeat the above steps.
[0028] In step S1: The initial docking is achieved by assisted by a tugboat or floating crane, where the staggered docking plates at both ends of the docking pipes are inserted into each other. The tie rod is a threaded tie rod, with nuts on the inner and outer sides of each limiting plate, i.e., inner and outer nuts. The welding spacing is controlled by tightening the inner and outer nuts to the required positions. First, the two ends of the initial docking are pulled closer to the welding condition by tightening the outer nuts of the limiting plates using the threaded tie rods; then, the inner nuts of the limiting plates are tightened to ensure that the distance between the two pipes is appropriate, avoiding excessive distance and ensuring an appropriate weld spacing.
[0029] In step S2: the water-stopping component is a water-swellable water-stopping strip, which is pasted on the outer wall of the pontoon where it contacts the immersed tube; the pontoon includes an upper semi-circular plate hoop and a lower semi-circular plate hoop. During installation, the lower plate hoop is hoisted first to fit against the lower outer wall of the immersed tube and the water-stopping component is installed, and then the upper plate hoop is installed. The upper and lower plate hoops are connected by bolts to form a complete clamping structure.
[0030] This invention achieves millimeter-level accuracy in the underwater connection of immersed tubes through a forced alignment method using external tie rods and internal support plates, ensuring the pipeline's alignment meets requirements. By constructing an underwater docking pontoon, a dry working environment for underwater tube docking is achieved, guaranteeing the quality of welding and corrosion protection. The underwater docking pontoon is fixedly connected to the pipeline via clamps, enabling simultaneous underwater docking of multiple sections of immersed tubes. The docking process is simple and rapid, improving construction efficiency. This rapid underwater docking technology for steel pipes features a simple structure and convenient operation. Compared to renting large areas of land for the entire immersed tube fabrication on shore or setting up an underwater construction platform, it has lower costs, less environmental impact, and significant economic and social benefits.
[0031] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0032] In the description of this invention, it should be understood that the terms "center," "height," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.
[0033] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.
[0034] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0035] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.
Claims
1. A method for underwater docking of immersed tubes, characterized in that, Includes the following steps: Step S1: Install limiting plates and mating plates on each of the two interfaces of the immersed tube to be docked, and weld blind plates to both ends of the immersed tube; float the immersed tube to be docked to the docking water area for preliminary docking, so that the mating plates on both sides are inserted into the opposite pipe openings, and then pull the two interfaces of the immersed tube to be docked to a weldable distance by passing through the limiting plates on both sides with a tie rod. Step S2: Use a crane vessel to lift the pontoon to the interface of the immersed tube to be docked, so that the pontoon's plate clamps fit into the outer wall of the immersed tube to be docked, and set a water-stopping component between the plate clamps and the outer wall to form a closed space; then pump out the water accumulated in the pontoon's sump. Step S3: Weld the interface of the immersed tube to be docked. After welding, enter the tube through the manhole reserved on the immersed tube to be docked, remove the blind plate and the docking plate, and finally seal the manhole. Step S4: Fill the pontoon with water, loosen the plate clamps to disconnect the pontoon from the immersed tube to be docked, use a crane vessel to lift the pontoon away and float it to the next docking point, and repeat the above steps.
2. The underwater docking construction method for immersed tubes as described in claim 1, characterized in that, In step S1: the initial docking is achieved by assisted by a tugboat or floating crane, which inserts the staggered docking plates at both ends of the docking pipe into the opposite pipe openings.
3. The underwater docking construction method for immersed tubes as described in claim 1, characterized in that, The pull rod is a threaded pull rod, and nuts are provided on the inner and outer sides of each limiting plate. The welding spacing is controlled by tightening the inner and outer nuts to the required position.
4. The underwater docking construction method for immersed tubes as described in claim 1, characterized in that, In step S2: the water-stopping component is a water-swellable water-stopping strip, which is pasted on the outer wall of the pontoon where it contacts the immersed tube; the pontoon includes an upper semi-circular plate hoop and a lower semi-circular plate hoop. During installation, the lower plate hoop is hoisted first to fit against the lower outer wall of the immersed tube and the water-stopping component is installed, and then the upper plate hoop is installed. The upper and lower plate hoops are connected by bolts to form a complete clamping structure.
5. The underwater docking construction method for immersed tubes as described in claim 1, characterized in that, The bottom of the pontoon is equipped with a sandwich layer. When the water in the pontoon's sump is pumped out, the water in the sandwich layer is retained to resist the buoyancy of the pontoon's bottom plate.
6. The underwater docking construction method for immersed tubes as described in claim 1, characterized in that, In step S4, the pontoon removal includes: first, filling the pontoon with water to the full capacity to increase sinking stability or eliminate buoyancy interference, then loosening the plate clamps, and finally being lifted away by a crane vessel; after the pontoon is removed, it is configured to be reusable and movable to the next immersed tube docking interface.
7. A floating box for underwater docking of submerged pipes, characterized in that, include: The enclosure is made of sheet metal and includes a bottom plate, side plates, and a top plate. The plate hoop includes an upper semi-circular plate hoop and a lower semi-circular plate hoop, wherein the lower semi-circular plate hoop is recessed into the top plate of the box body. The interlayer includes an interlayer plate connected inside the side panel of the box body, with water collection pits provided at the four corners of the interlayer plate, and the interlayer plate is arranged opposite to the bottom plate.
8. The pontoon as described in claim 7, characterized in that, The interlayer includes channel steels disposed on the base plate, the channel steels being arranged in a cross pattern to form a load-bearing frame, the top of the load-bearing frame being provided with the interlayer plate, and the height between the interlayer plate and the base plate being between 400 and 500 mm.
9. The pontoon as described in claim 7, characterized in that, The plate hoop is equipped with a water-stopping component.