A deep sea pipeline foundation module with reversible granular ballast attitude control and method of construction

Abstract

The application discloses a deep-sea pipeline foundation module with reversible granular ballast attitude adjustment and a construction method, and relates to the technical field of structure construction. The module comprises a pipeline supporting main body, a granular ballast assembly, a buoyancy adjusting assembly and a detection assembly. The granular ballast assembly increases the ballast amount by sand feeding and water draining, and reduces the ballast amount by sand flushing to resuspend and discharge the sea sand; the multiple granular ballast assemblies differentially inject and discharge sand, change the mass distribution and the barycentric position of the module, and realize sinking and attitude adjustment. The buoyancy adjusting assembly adopts an air bag with a buffer pad, supports and lowers the pipeline after the module is grounded, and gradually discharges air to lower the pipeline to a predetermined supporting position. When the pipeline is re-laid, sand discharging is used to reduce the load, and the air bag is inflated to restore the adjustable state. The application can realize reversible ballast of the foundation module, differential attitude adjustment, repositioning and pipeline buffer lowering.

Description

Technical Field

[0001] This invention belongs to the field of structural construction technology, and specifically relates to an underwater foundation structure layout and attitude adjustment technology, particularly to a deep-sea pipeline foundation module and construction method with reversible particle ballast attitude adjustment. Background Technology

[0002] Submarine pipelines are crucial energy and material transport facilities in deep-sea oil and gas transportation, seabed resource development, and cross-sea engineering construction. Due to factors such as high hydrostatic pressure, complex seabed topography, soft seabed, and seabed hydrodynamics, deep-sea pipelines typically require foundations for support and positioning. Therefore, the accurate placement, stable placement, and reliable support of pipeline foundations for subsequent pipelines are of paramount importance.

[0003] Existing pipeline foundations typically employ steel support structures, concrete foundations, or other prefabricated counterweight structures, and are hoisted to their designated positions using surface lifting equipment. The weight and counterweight of such foundations are usually determined before construction, and position and attitude control during underwater deployment relies primarily on external hoisting equipment. When affected by ocean currents, swaying slings, or seabed undulations, the foundation modules are prone to tilting or attitude deviations. Real-time corrections using external equipment in deep-water environments suffer from response lag and limited adjustment accuracy. Simultaneously, the foundation modules need to ensure stable sinking and bottoming, while also possessing a certain capacity for weight adjustment and repositioning in case of deployment deviations. Therefore, achieving adjustable underwater mass and center of gravity is a problem that needs to be solved during the deployment of deep-sea pipeline foundations.

[0004] Furthermore, after the foundation module is in place, it must also support the lowered deep-sea pipeline. When the pipeline transitions from a suspended state to a foundation-supported state, it is susceptible to localized impacts with the foundation due to factors such as lowering speed, lateral offset, and attitude deviations, leading to uneven stress or deviations in its placement position. Therefore, how to provide buffer support for the pipeline after the foundation is in place and ensure its stable entry into the predetermined support position is also a problem that needs to be solved in deep-sea pipeline construction.

[0005] Existing technologies for ballasting underwater foundations or large marine structures already utilize water, sand, or other high-density materials. For example, US3490239A discloses a movable breakwater structure with multiple ballast tanks inside, which allows for the sinking, placement, and refloating of the structure by loading and removing ballast. This type of technology can alter the overall weight of the underwater structure and improve stability during transportation and placement by utilizing ballast tanks at different locations. However, it primarily focuses on the overall buoyancy and placement of large structures such as breakwaters, and lacks specific adjustment methods for the mass distribution and center of gravity adjustments required during the deployment of deep-sea pipeline foundations due to localized attitude deviations.

[0006] US20180073665A1 further discloses a technology for reducing the load on floating structures using high-density solid materials. The ballast material can be granular solid, and after the structure reaches a predetermined underwater position, the ballast material can be dissolved, suspended, or diluted by water flow before being discharged with the water. However, for underwater foundations using sea sand as the ballast medium, the sea sand has a certain degree of accumulation after settling inside the hull, and the sand layer height continuously changes during the discharge process. How to ensure that the deposited sea sand can be effectively extracted at different stages of sand discharge and avoid local residual sand affecting the load reduction effect still requires further consideration.

[0007] For continuous extraction of granular materials, DE202014105625U1 discloses a suction pipe for containers of bulk materials. The suction gun in this device can move within an outer sleeve. After the granular material below the suction head is removed, the suction gun can continue to move downwards, thus continuously suctioning as the granular material level decreases. This technology is mainly aimed at negative pressure air conveying of bulk materials such as plastic granules and grains. The suction gun uses a sleeve guide and moves downwards with the material being extracted. For the discharge of sedimented sea sand in deep-water environments after it has been disturbed by water flow to form a sand-water mixture, the properties of the granular medium, the conveying medium, and the movement conditions of the sand extraction point all vary significantly. There is still room for further improvement in how to maintain stable sand extraction under continuously changing sand layer conditions.

[0008] The aforementioned existing technologies involve techniques such as ballast loading and unloading of granular materials, granular material level tracking and extraction, airbag-assisted underwater structure submersion, and airbag-supported subsea pipelines. However, each technology primarily addresses independent construction stages and technical issues. For deep-sea pipeline foundation modules, it remains necessary to address the coordinated adjustment of mass, center of gravity, and buoyancy during the foundation module's sinking process, as well as how to ensure the flexible support and stable placement of the deep-sea pipeline after the foundation is on the seabed without the need for additional dedicated pipeline buffer devices. Furthermore, when using sea sand as a reversible granular ballast, it is also necessary to address the difficulty of maintaining the sand discharge port stably at an effective sand extraction position under conditions of continuously changing sand layer height. Therefore, it is necessary to provide a deep-sea pipeline foundation module and construction method that enables reversible adjustment of local granular ballast volume, utilizes changes in mass distribution for attitude correction, and allows the same buoyancy adjustment component to function continuously in both the foundation deployment and pipeline placement phases. Summary of the Invention

[0009] The purpose of this invention is to provide a reversible particle ballast attitude adjustment deep-sea pipeline foundation module and construction method to solve the problems of difficulty in adjusting the mass and center of gravity of the deep-sea pipeline foundation module during underwater deployment, difficulty in readjusting after deployment deviation, and lack of buffer support for the subsequent pipeline after the foundation module sits on the bottom.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A deep-sea pipeline foundation module with reversible particle ballast attitude adjustment includes a pipeline support body, multiple particle ballast components disposed on the side of the pipeline support body, a buoyancy adjustment component disposed inside the pipeline support body, and a detection component disposed on the upper end of the particle ballast components.

[0012] Furthermore, multiple particle ballast components are distributed at different positions of the pipeline support body, and each particle ballast component can respectively input and discharge sea sand, thereby changing the self-weight and mass distribution of the pipeline support body by adjusting the particle ballast amount at different positions.

[0013] Furthermore, multiple particle ballast assemblies are respectively disposed on opposite sides of the pipeline support body. By inputting sea sand into the particle ballast assemblies on opposite sides or discharging sea sand from the corresponding particle ballast assemblies, a particle ballast difference is formed on both sides of the pipeline support body.

[0014] Preferably, multiple particle ballast assemblies are arranged side by side on opposite sides of the pipeline support body, or in an array in the side region of the pipeline support body, so that particle ballast assemblies at different positions can participate in the mass distribution and center of gravity adjustment of the pipeline support body respectively.

[0015] Furthermore, by altering the mass distribution and center of gravity of the pipeline support body through the difference in particle ballast, the tilting posture of the pipeline support body can be adjusted.

[0016] Furthermore, the particle ballast assembly includes several drainage holes, a sand and water input channel, a sand and water output channel, a sand-permeable pipe, and a sand-flushing pipe. The sand and water input channel, the sand and water output channel, and the sand-flushing pipe are respectively connected to the interior of the particle ballast assembly, and the sand-permeable pipe is connected to the sand and water output channel.

[0017] Furthermore, the sand-water mixture formed by sea sand and seawater enters the particle ballast assembly through the sand-water input channel. The sea sand inside the particle ballast assembly gradually settles and remains, while excess seawater is discharged through the drainage hole, thereby increasing the amount of sea sand inside the particle ballast assembly and thus increasing the particle ballast at the corresponding position.

[0018] Preferably, the drainage hole is located at the upper part of the particle ballast assembly, preferably near the uppermost end of the particle ballast assembly, so that after the sand-water mixture enters the particle ballast assembly, the sea sand preferentially settles downwards under the action of gravity, while the seawater above the sea sand layer is discharged through the drainage hole, thereby reducing the loss of sea sand with drainage.

[0019] Furthermore, a reinforced flange is provided at the connection between the sand and water input channel and the particle ballast assembly to strengthen the connection between the sand and water input channel and the particle ballast assembly.

[0020] Furthermore, when it is necessary to reduce the amount of ballast particles in the ballast assembly, flushing water is introduced into the ballast assembly through the flushing pipe, so that the sea sand that has been deposited in the ballast assembly is disturbed by the water flow and resuspended, forming a sand-water mixture that can be discharged with the water flow.

[0021] Furthermore, a water turbine valve is installed at the outlet end of the flushing pipe. The water turbine valve is used to spray the flushing water transported through the flushing pipe in multiple directions inside the particle ballast assembly, thereby expanding the disturbance range of the flushing water on the deposited sea sand. The sand-water mixture formed by the disturbance of the flushing water enters the sand-water output channel through the sand-permeable pipe, and is discharged from the particle ballast assembly through the sand-water output channel, thereby reducing the particle ballast amount at the corresponding location.

[0022] Furthermore, the sand-permeable pipe includes a track wire, a pipe opening baffle, and a spring pipe. The track wire extends into the interior of the particle ballast assembly, and the spring pipe is telescopically oriented along the extension direction of the track wire. The pipe opening baffle is located at the sand inlet end of the spring pipe. The track wire is used to limit the telescopic path of the spring pipe, enabling the spring pipe to extend and retract in a predetermined direction.

[0023] Furthermore, the spring pipe has an elastic restoring force that allows its sand inlet end to extend along the track wire toward the surface of the sea sand layer. After the pipe opening barrier contacts the surface of the sea sand layer, it limits the further extension of the spring pipe.

[0024] Preferably, when there is a large amount of sea sand inside the granular ballast assembly, the pipe opening is supported by the surface of the sea sand layer, causing the spring pipe to be in a relatively contracted state; as the surface of the sea sand layer decreases, the spring pipe gradually extends under the action of elastic restoring force.

[0025] Preferably, the pipe opening barrier restricts the sand inlet end of the spring pipe from continuing to extend into the sea sand layer by contacting the surface of the sea sand layer, so that the sand inlet end remains near the surface of the sea sand layer.

[0026] Furthermore, as the sea sand inside the granular ballast assembly is continuously discharged through the sand-permeable pipe, the surface height of the sea sand layer gradually decreases, and the limiting position formed by the pipe opening barrier on the spring pipe decreases accordingly. Under the action of its own elastic restoring force, the spring pipe continues to extend along the track wire, so that the sand inlet end of the spring pipe moves as the surface of the sea sand layer decreases.

[0027] Preferably, after the spring pipe is lowered to the surface of the sea sand layer, it continues to extend towards the sea sand layer through its own elastic restoring force, and is re-in contacted with the lowered sea sand layer surface by the pipe opening enclosure, so that the sand inlet end of the spring pipe is continuously kept at the surface of the sea sand layer for sand extraction.

[0028] Preferably, when reducing the particle ballast load of the particle ballast assembly, the flushing water is introduced into the sand flushing pipe and the sand-water mixture is discharged from the sand permeation pipe simultaneously, so that the sea sand that is resuspended due to the disturbance of the flushing water is discharged in a timely manner through the sand permeation pipe and the sand-water output channel, thereby reducing the resettling of the sea sand.

[0029] Furthermore, inputting sea sand into the particle ballast assembly through the sand-water input channel can increase the particle ballast volume, while discharging sea sand through the sand flushing pipe, sand permeation pipe, and sand-water output channel can reduce the particle ballast volume, thereby enabling the particle ballast assembly to perform reversible particle ballast adjustment.

[0030] Furthermore, by controlling the input or discharge of sea sand through the particle ballast components at different locations, the mass at different locations can be changed without altering the basic structure of the pipeline support body, thereby changing the center of gravity of the pipeline support body.

[0031] Preferably, when it is necessary to adjust the tilt of the pipeline support body to one side, the particle ballast on the corresponding side is increased, the particle ballast on the other side is decreased, or a combination of both is used to make the center of gravity of the pipeline support body change to correct the tilt.

[0032] Furthermore, the detection component is disposed at the upper end of the particle ballast component and is used to detect the underwater attitude state of the pipeline support body. Based on the underwater attitude state detected by the detection component, the particle ballast component that needs to be fed or discharged with sea sand is determined, and the particle ballast amount at the corresponding position is increased or decreased. By changing the amount and mass distribution of deposited sea sand at the corresponding position, the underwater attitude of the pipeline support body is corrected.

[0033] Preferably, the detection component is also used to acquire underwater location information of the pipeline support body to assist in tracing and confirming the location of the pipeline support body in deep water environments.

[0034] Preferably, the detection component can also record the production and installation information of the pipeline support body and the deep-sea pipeline it supports, so as to verify the relevant information during the later operation and maintenance process.

[0035] Furthermore, the pipeline support body forms a support area for receiving the deep-sea pipeline, and the cross-section of the support area is an inverted trapezoid that is wider at the top and narrower at the bottom. The buoyancy adjustment component is an airbag integrally equipped with a buffer pad, and is respectively disposed on the two opposite inner sidewalls of the support area.

[0036] Furthermore, during the sinking process of the pipeline support body, the buoyancy of the pipeline support body is adjusted by changing the inflation state of the buoyancy adjustment component, and this is coordinated with the adjustment of the self-weight of the pipeline support body by the particle ballast component, so that the pipeline support body sinks under the combined action of its own weight and buoyancy.

[0037] Furthermore, during the underwater deployment of the pipeline support body, the particle ballast assembly mainly adjusts the self-weight, mass distribution, and center of gravity of the pipeline support body by changing the particle ballast amount at different locations, while the buoyancy adjustment assembly mainly adjusts the buoyancy of the pipeline support body by changing the inflation state. The two are adjusted separately or in combination to simultaneously meet the adjustment requirements of the sinking state and underwater attitude of the pipeline support body.

[0038] Furthermore, the buoyancy adjustment component maintains the same installation position during the sinking phase of the pipeline support body and the deep-sea pipeline support phase after the pipeline support body reaches the seabed. After the pipeline support body is situated on the seabed, the buoyancy adjustment component remains on the inner wall of the support area and remains inflated to support the subsequently lowered deep-sea pipeline. When the deep-sea pipeline is lowered into the support area, it first contacts the buoyancy adjustment component, which, along with its integrally formed buffer pad, cushions and supports the pipeline.

[0039] Furthermore, after the deep-sea pipeline is supported by the buoyancy adjustment component, the buoyancy adjustment component is gradually vented, so that its support height for the deep-sea pipeline is gradually reduced, thereby causing the deep-sea pipeline to gradually descend along the support area to the predetermined support position.

[0040] Preferably, the buoyancy adjustment components on both sides simultaneously vent air, causing the deep-sea pipeline to gradually decrease its support height and descend towards the predetermined support position. Alternatively, the buoyancy adjustment components on both sides vent air separately, adjusting the attitude of the deep-sea pipeline during its lowering process by changing the support height on both sides.

[0041] Preferably, the buoyancy adjustment component is in a high inflation state before the pipeline support body begins to sink, and maintains the inflation state or only makes small adjustments during the sinking process. By increasing the particle ballast of the particle ballast component, the pipeline support body will sink, thereby preserving a large initial buffer support capacity for the subsequent deep-sea pipeline after the pipeline support body sits on the bottom.

[0042] Furthermore, the buoyancy adjustment component is used to adjust the buoyancy of the pipeline support body during the sinking stage, and continues to support and buffer the subsequent lowering of the deep-sea pipeline after the pipeline support body has settled on the bottom, and gradually allows the deep-sea pipeline to enter the predetermined support position by venting.

[0043] Furthermore, when the pipeline support body is already located on the seabed and needs to be readjusted, flushing water is introduced into the corresponding particle ballast assembly through the sand flushing pipe to resuspend the deposited sea sand and discharge the resulting sand-water mixture through the sand permeation pipe and sand-water output channel, thereby reducing the particle ballast load of the pipeline support body.

[0044] Furthermore, simultaneously with or subsequently after the discharge of sea sand, the buoyancy adjustment component is inflated to increase the buoyancy of the pipeline support body, reduce the contact load of the pipeline support body on the seabed, and change the pipeline support body from a stable bottom-sitting state to a reduced-load state for placement adjustment. After the placement position is re-determined, sea sand is again fed into the corresponding particle ballast component, and the inflation state of the buoyancy adjustment component is adjusted to allow the pipeline support body to sink again and settle in the predetermined position.

[0045] A method for deep-sea pipeline foundation construction and pipeline lowering using the aforementioned reversible particle ballast attitude adjustment deep-sea pipeline foundation module includes the following steps:

[0046] S1 involves deploying the deep-sea pipeline foundation module into the seawater and inflating the buoyancy adjustment components.

[0047] S2, a mixture of sea sand and seawater is fed into multiple granular ballast assemblies, so that the sea sand enters the interior of the granular ballast assembly through the sand-water input channel and settles, and the excess seawater is discharged through the drainage hole. By increasing the granular ballast of multiple granular ballast assemblies, the pipeline support body sinks.

[0048] S3, during the sinking process of the pipeline support body, the underwater attitude state of the pipeline support body is detected by the detection component, and the amount of sea sand in the particle ballast components at different positions is adjusted according to the detected underwater attitude state to change the mass distribution and center of gravity position of the pipeline support body, thereby adjusting the underwater attitude of the pipeline support body, and adjusting the sinking state of the pipeline support body by adjusting the inflation state of the buoyancy adjustment component.

[0049] S4, adjust the particle ballast amount of the multiple particle ballast components and the inflation state of the buoyancy adjustment component so that the pipeline support body sinks and sits on the seabed in a predetermined posture; after the pipeline support body sits on the seabed, the buoyancy adjustment component continues to be set on the inner side wall of the support area and retains the inflation state for supporting the deep-sea pipeline.

[0050] S5, the deep-sea pipeline is lowered into the support area, so that the deep-sea pipeline first contacts the buoyancy adjustment component, and the buoyancy adjustment component buffers and supports the deep-sea pipeline.

[0051] S6, gradually vent the buoyancy adjustment component to gradually reduce its support height for the deep-sea pipeline, thereby causing the deep-sea pipeline to gradually descend along the support area to the predetermined support position.

[0052] Preferably, in step S3, when it is necessary to increase the ballast of a certain particle, a sand-water mixture is introduced through the corresponding sand-water input channel; when it is necessary to reduce the ballast of a certain particle, flushing water is introduced through the sand flushing pipe to resuspend the deposited sea sand and discharge it through the sand permeation pipe and the sand-water output channel.

[0053] Preferably, in step S3, the amount of sea sand in the ballast components at different locations is adjusted in stages. After each sea sand transport is completed, the underwater attitude state of the pipeline support body is obtained again through the detection component, and it is determined whether to continue the ballast adjustment based on the new attitude state.

[0054] Preferably, in step S6, during the descent of the deep-sea pipeline, the venting state of the buoyancy adjustment components on both sides is adjusted according to the attitude of the deep-sea pipeline to change the support height on both sides and adjust the descent attitude of the deep-sea pipeline.

[0055] Furthermore, before the deep-sea pipeline is lowered, when the pipeline support body needs to be readjusted after being placed on the seabed, flushing water is introduced into the corresponding particle ballast assembly through the sand flushing pipe. This resuspends the deposited sea sand and forms a sand-water mixture, which is then discharged through the sand permeation pipe and sand-water outlet channel. During the sand discharge process, as the surface height of the sea sand layer decreases, the spring pipe continues to extend along the track wire under its own elastic restoring force. Its extension position is restricted by the pipe opening enclosure, causing the sand inlet end of the spring pipe to move as the surface height of the sea sand layer decreases.

[0056] Furthermore, while or subsequently reducing the particle ballast by removing sand, the buoyancy adjustment component is inflated to increase the buoyancy of the pipeline support body and reduce its contact load on the seabed, thus putting the pipeline support body into a reduced-load state. After adjusting the placement position of the pipeline support body, sea sand is again fed into the corresponding particle ballast component, and the inflation state of the buoyancy adjustment component is adjusted to allow the pipeline support body to sink again and settle in the predetermined position.

[0057] Preferably, when readjusting the placement of the pipeline support body, one or more of the particle ballast components are selected to discharge sand according to the current posture and the direction to be adjusted, so that the pipeline support body changes its mass distribution and center of gravity while reducing the overall load.

[0058] The technical effects and advantages of this invention are as follows:

[0059] 1. This invention uses multiple particle ballast components to input and discharge sea sand, which can change the particle ballast amount and mass distribution at different positions of the pipeline support body, realize the center of gravity adjustment and attitude correction during the sinking process of the foundation module, and improve the adjustability of underwater deployment.

[0060] 2. The present invention adopts a reversible particle ballast method, which uses flushing water to resuspend the deposited sea sand and discharge it through the sand-permeable pipe and sand-water output channel, thereby reducing the particle ballast amount; the sand inlet end of the sand-permeable pipe can move as the surface of the sea sand layer decreases, which is beneficial to maintaining the continuity and stability of the sand discharge process.

[0061] 3. This invention uses the buoyancy adjustment component for buoyancy adjustment during the sinking stage of the foundation module and for buffering and supporting the deep-sea pipeline after it has bottomed out. By gradually venting air, the deep-sea pipeline is smoothly lowered to the predetermined support position, reducing the need for setting up independent auxiliary components at different construction stages.

[0062] 4. After the basic module is settled on the seabed, the present invention can still reduce the load by removing sand and inflating the buoyancy adjustment component to reduce the contact load of the pipeline support body on the seabed, thereby adjusting the deployment position; after repositioning, sand can be added again to settle on the seabed, improving the basic module's ability to correct deployment deviations. Attached Figure Description

[0063] Figure 1 This is a side view of the deep-sea pipeline foundation module of the present invention.

[0064] Figure 2 This is a schematic cross-sectional view of the deep-sea pipeline foundation module of the present invention.

[0065] Figure 3 This is a schematic diagram of the particle ballast assembly structure of the present invention.

[0066] Figure 4 These are side and cross-sectional views of the sand-permeable pipe of the present invention.

[0067] Figure 5 This is a schematic diagram illustrating the working principle of the particle ballast assembly for sand infeeding and sand discharge for load reduction.

[0068] Figure 6 This is a schematic diagram illustrating the sinking and attitude adjustment working principle of the deep-sea pipeline foundation module of the present invention.

[0069] Figure 7 This is a schematic diagram illustrating the working principle of the present invention, which utilizes a buoyancy adjustment component to support a deep-sea pipeline.

[0070] Figure 8 This is a flowchart illustrating the method for deep-sea pipeline foundation construction and pipeline lowering using a deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to the present invention.

[0071] In the diagram: 100, Pipe support body; 200, Particle ballast assembly; 210, Drainage hole; 220, Reinforced flange; 230, Sand and water input channel; 240, Sand and water output channel; 250, Sand-permeable pipe; 251, Track wire; 252, Pipe opening enclosure; 253, Spring pipe; 260, Sand flushing pipe; 270, Water turbine valve; 300, Buoyancy adjustment assembly; 400, Detection assembly. Detailed Implementation

[0072] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0073] It should be understood that the detection component is used to obtain the underwater attitude state of the pipeline support body, and its specific detection principle and signal acquisition method can be implemented using existing mature technologies in the field. The focus of this invention is to determine the adjustment direction of the particle ballast amount of the corresponding particle ballast component by using the detected attitude state, and to achieve underwater attitude adjustment by changing the amount and mass distribution of deposited sea sand at different locations. Therefore, the specific detection principle of the detection component itself is not limited.

[0074] It should be understood that the transportation of the sand-water mixture, the supply of flushing water, and the inflation and deflation of the buoyancy adjustment components can be achieved through existing underwater construction equipment connected to the corresponding channels. The specific power equipment, supply method, and control method can be selected according to the construction water depth and site conditions. This invention mainly relates to the particle ballast adjustment, sand discharge and buoyancy adjustment processes after the aforementioned medium enters the foundation module, and does not limit the specific structure of the external supply equipment.

[0075] It should be noted that after the pipeline support body is deloaded by sand removal and inflated with buoyancy adjustment components to reduce its contact load on the seabed, the position of the pipeline support body can be adjusted using existing hoisting, towing, or deployment equipment used in underwater construction. The key point of the redeployment process described in this invention is to transform the pipeline support body from a stable bottom-sitting state to a deloaded state that facilitates position adjustment by reducing the particle ballast and increasing buoyancy. The construction equipment used for external towing or position adjustment can be selected according to the site construction conditions.

[0076] First Embodiment

[0077] This embodiment details the overall structure of the deep-sea pipeline foundation module for reversible particle ballast attitude adjustment and the arrangement relationships between its components, such as... Figure 1 , Figure 2 and Figure 3 As shown.

[0078] (1) The deep-sea pipeline foundation module includes a pipeline support body (100), multiple particle ballast components (200), a buoyancy adjustment component (300), and a detection component (400). The pipeline support body (100) constitutes the main load-bearing structure of the foundation module. Multiple particle ballast components (200) are disposed on the side of the pipeline support body (100). The buoyancy adjustment component (300) is disposed in the support area formed inside the pipeline support body (100). The detection component (400) is disposed at the upper end of the particle ballast component (200).

[0079] (2) Multiple granular ballast assemblies (200) are arranged at different positions along the pipeline support body (100). In this embodiment, multiple granular ballast assemblies (200) are located on opposite sides of the pipeline support body (100), so that different positions of the pipeline support body (100) can form independent granular ballast adjustment positions. During construction, sea sand can be fed into or discharged from each granular ballast assembly (200), thereby changing the mass at the corresponding position.

[0080] (3) When the amount of sea sand in the ballast assemblies (200) on both sides is basically the same, the ballast load on both sides of the pipeline support body (100) is relatively balanced; when the amount of sea sand in one of the ballast assemblies (200) increases or decreases, a difference in ballast load is formed on both sides of the pipeline support body (100), thereby changing the mass distribution and center of gravity of the pipeline support body (100). Therefore, the corresponding attitude correction effect can be obtained by adjusting the ballast load at different positions.

[0081] (4) The specific number and arrangement of the multiple granular ballast components (200) can be determined according to the size and posture adjustment requirements of the pipeline support body (100). In this embodiment, multiple granular ballast components (200) are arranged side by side on the side of the pipeline support body (100), so that the granular ballast components (200) at different positions can participate in the self-weight, mass distribution and center of gravity adjustment of the foundation module respectively.

[0082] (5) A support area for receiving the deep-sea pipeline is formed in the middle of the pipeline support body (100). The cross-section of the support area is an inverted trapezoid with a wider top and a narrower bottom. The buoyancy adjustment component (300) is set on the two opposite inner sidewalls of the support area. The buoyancy adjustment component (300) adopts an airbag structure with an integrated buffer pad. During the underwater deployment of the basic module, the buoyancy of the pipeline support body (100) is changed by its own inflation state. After the pipeline support body (100) is placed on the seabed, the buoyancy adjustment component (300) remains in its original installation position to receive the subsequently deployed deep-sea pipeline.

[0083] (6) The detection component (400) is used to obtain the underwater attitude state of the pipeline support body (100). During construction, the position where the particle ballast needs to be increased or decreased is determined based on the attitude state obtained by the detection component (400). Then, the corresponding particle ballast component (200) is used to input or discharge sea sand, so that the detection results correspond to the adjustment of particle ballast at different positions.

[0084] (7) In this embodiment, the particle ballast assembly (200) is mainly used to change the self-weight, mass distribution and center of gravity of the pipeline support body (100), and the buoyancy adjustment assembly (300) is mainly used to change the buoyancy of the pipeline support body (100). The two can be adjusted separately, or they can cooperate with each other during the underwater deployment of the base module, so that the base module has both sinking state adjustment and attitude adjustment capabilities.

[0085] Second Embodiment

[0086] This embodiment details the sand inlet and outlet processes of the granular ballast assembly (200), as well as the sand extraction process of the sand-passing pipe (250) as the surface of the sea sand layer changes. Figure 3 , Figure 4 and Figure 5 As shown.

[0087] (1) When it is necessary to increase the granular ballast, the mixture of sea sand and seawater is transported to the sand-water input channel (230) by existing external construction equipment. After the sand-water mixture enters the granular ballast assembly (200) along the sand-water input channel (230), a sand-water separation process is formed inside the granular ballast assembly (200). Among them, the sea sand gradually settles downward under the action of gravity and remains inside the granular ballast assembly (200), while the excess seawater above the sea sand layer is discharged through the drainage hole (210) located at the top.

[0088] (2) As the sand-water mixture is continuously fed in, the amount of sea sand deposited inside the granular ballast assembly (200) gradually increases, and the mass at the corresponding position increases accordingly. By controlling the sand feeding process of different granular ballast assemblies (200) respectively, each granular ballast assembly (200) can have the same or different amounts of deposited sea sand, thereby increasing the overall self-weight of the pipeline support body (100) and changing the mass distribution between different positions.

[0089] (3) When it is necessary to reduce the particle ballast load of the particle ballast assembly (200), flushing water is introduced into the particle ballast assembly (200) through the sand flushing pipe (260). The outlet end of the sand flushing pipe (260) is equipped with a water turbine valve (270). The flushing water is sprayed into the particle ballast assembly (200) in multiple directions through the water turbine valve (270), which disturbs the deposited sea sand, so that the sea sand that was originally in the sedimentary state is resuspended in the water and forms a sand-water mixture that can flow.

[0090] (4) During the flushing process, the sand-permeable pipe (250) extracts sand from the sand-water mixture that has been resuspended. The sand-water mixture passes through the sand-permeable pipe (250) and the sand-water output channel (240) in sequence and is discharged from the particle ballast assembly (200). In this embodiment, the flushing water entering the sand-flushing pipe (260) and the sand-water mixture being discharged from the sand-permeable pipe (250) can be carried out simultaneously, so that the disturbed and resuspended sea sand can be discharged in time, reducing the resettling of sea sand.

[0091] (5) The sand-permeable pipe (250) includes a track wire (251), a pipe opening barrier (252), and a spring pipe (253). The track wire (251) extends into the particle ballast assembly (200) to limit the extension path of the spring pipe (253); the spring pipe (253) is extendable along the extension direction of the track wire (251); the pipe opening barrier (252) is located at the sand inlet end of the spring pipe (253).

[0092] (6) The spring pipe (253) itself has an elastic restoring force that causes its sand inlet end to extend along the track wire (251) toward the surface of the sea sand layer. When there is a lot of deposited sea sand inside the particle ballast assembly (200), the pipe opening barrier (252) contacts the surface of the sea sand layer, and the sea sand layer provides support and limit to the pipe opening barrier (252), preventing the spring pipe (253) from continuing to extend in that direction. At this time, the spring pipe (253) maintains a telescoping state corresponding to the current height of the sea sand layer.

[0093] (7) During the sand discharge process, the sand-water mixture located near the sand inlet end of the sand-permeable pipe (250) continuously enters the spring pipe (253) and is discharged through the sand-water outlet channel (240). The total amount of sea sand inside the particle ballast assembly (200) gradually decreases, and the surface of the sea sand layer also drops. When the surface of the sea sand layer of the original support pipe opening enclosure (252) drops, the original limit position drops accordingly, and the spring pipe (253) continues to extend along the track wire (251) under its own elastic restoring force.

[0094] (8) After the spring pipe (253) continues to extend, the pipe opening guard (252) set at its sand inlet end contacts the lowered sea sand layer surface again and re-establishes a limit at the new sea sand layer height. Thus, as the sea sand layer surface continues to decrease, the spring pipe (253) can repeat the above extension and limit process, so that its sand inlet end is always near the sea sand layer surface, instead of remaining at the initial fixed height.

[0095] (9) In addition to forming a sand surface limit, the pipe opening barrier (252) is also used to restrict the sand inlet end of the spring pipe (253) from continuing to extend excessively into the sea sand layer. When the pipe opening barrier (252) contacts the surface of the sea sand layer, the support of the sea sand layer on the pipe opening barrier (252) restricts the spring pipe (253) from continuing to extend, so that the sand inlet end is kept in a position that is conducive to sand extraction.

[0096] Third Embodiment

[0097] This embodiment details the particle ballast, buoyancy adjustment, and differential attitude control processes of the deep-sea pipeline foundation module from its launch to its placement on the seabed. Figure 1 , Figure 2 , Figure 5 , Figure 6 and Figure 8 As shown.

[0098] (1) At the start of construction, the deep-sea pipeline foundation module is launched into the water and the buoyancy adjustment component (300) is inflated. Before the pipeline support body (100) sinks, the buoyancy adjustment component (300) can be in a high inflation state so that the pipeline support body (100) maintains the corresponding buoyancy during the initial underwater deployment process.

[0099] (2) A mixture of sea sand and seawater is introduced into multiple granular ballast components (200) through the sand-water input channel (230). After the sand-water mixture enters the granular ballast components (200), the sea sand gradually settles, and the excess seawater is discharged through the drainage hole (210). As the amount of sea sand deposited in each granular ballast component (200) increases, the overall self-weight of the pipeline support body (100) increases. When its sinking conditions are met, the pipeline support body (100) sinks towards the seabed under the combined action of its own weight and buoyancy.

[0100] (3) When the basic module is initially lowered, multiple granular ballast components (200) can first form a relatively balanced granular ballast state, so that the pipeline support body (100) can be lowered under the condition of basically balanced mass distribution. At the same time, the underwater attitude state of the pipeline support body (100) can be continuously or in stages obtained by the detection component (400).

[0101] (4) When the underwater attitude status obtained by the detection component (400) indicates that the pipeline support body (100) is tilted, the particle ballast component (200) that needs to be adjusted is determined according to the tilt direction. If tilting occurs, the amount of sedimented sea sand in the particle ballast component (200) on that side can be increased; some sea sand can also be discharged from the particle ballast component (200) on the other side, or a method of increasing sand on one side and discharging sand on the other side can be adopted at the same time.

[0102] (5) When it is necessary to increase the particle ballast at a certain location, a sand-water mixture is introduced through the corresponding sand-water input channel (230) to allow the sea sand to be deposited inside the particle ballast assembly (200); when it is necessary to decrease the particle ballast at a certain location, flushing water is introduced through the corresponding flushing pipe (260) to allow the deposited sea sand to be resuspended and discharged through the sand-permeable pipe (250) and the sand-water output channel (240).

[0103] (6) The posture adjustment process can be carried out in stages. After each adjustment, the detection component (400) obtains the real-time status and then determines whether to continue the adjustment and the position to be adjusted next.

[0104] (7) Simultaneously with the adjustment of the particle ballast, the inflation state of the buoyancy adjustment component (300) can be adjusted according to the sinking state of the foundation module. The particle ballast component (200) mainly changes the self-weight and center of gravity of the pipeline support body (100) by the amount of sea sand, and the buoyancy adjustment component (300) mainly changes the buoyancy of the pipeline support body (100) by the inflation state, so that the two together control the foundation module.

[0105] (8) The pipeline support body (100) is located on the seabed. After it sits on the seabed, the sedimentary sea sand retained in the particle ballast assembly (200) forms the ballast mass of the base module. The buoyancy adjustment assembly (300) is not removed from the pipeline support body (100), but continues to be held on the two inner sidewalls of the support area to provide support conditions for the next stage of deep-sea pipeline lowering operation.

[0106] Fourth embodiment

[0107] This embodiment details the process of the pipeline support body (100) being placed on the seabed, and how the existing buoyancy adjustment component (300) buffers, supports, and gradually lowers the subsequently lowered deep-sea pipeline. Figure 2 , Figure 7 and Figure 8 As shown.

[0108] (1) When the pipeline support body (100) is on the bottom, the buoyancy adjustment component (300) is kept in an inflated state to support the deep-sea pipeline. Then the construction equipment gradually lowers the deep-sea pipeline to the support area above the pipeline support body (100).

[0109] (2) As the deep-sea pipeline continues to descend, it first comes into contact with the buoyancy adjustment components (300) located on the two inner walls of the support area. After contacting the deep-sea pipeline, the buoyancy adjustment components (300) buffer and support the deep-sea pipeline, thus slowly transitioning it from a suspended state to a foundation-supported state.

[0110] (3) After the deep-sea pipeline is supported by the buoyancy adjustment components (300) on both sides, the buoyancy adjustment components (300) are gradually vented. As the gas inside is gradually vented, the support height formed by the buoyancy adjustment components (300) on the deep-sea pipeline gradually decreases, and the deep-sea pipeline moves downward along the support area.

[0111] (4) As the venting process continues, the supporting effect of the buoyancy adjustment component (300) gradually decreases, and the deep-sea pipeline eventually enters the predetermined support position.

[0112] Fifth embodiment

[0113] This embodiment details the process of sand removal, buoyancy enhancement, and repositioning of the foundation module when the pipeline support body (100) is already situated on the seabed, but the deployment position needs adjustment before the deep-sea pipeline is lowered. Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 8 As shown.

[0114] (1) After the pipeline support body (100) is located on the seabed, if it is found that the placement position needs to be further adjusted before the deep-sea pipeline is laid, one or more particle ballast components (200) that need to reduce the particle ballast amount are determined first based on the current underwater attitude and the direction to be adjusted.

[0115] (2) Flushing water is introduced through the flushing pipe (260) of the corresponding particle ballast assembly (200). The flushing water is sprayed in multiple directions through the water turbine valve (270) set at the outlet of the flushing pipe (260) to disturb the deposited sea sand and resuspend the deposited sea sand to form a sand-water mixture.

[0116] (3) While the flushing water is continuously agitated, a sand-water mixture is obtained through the sand-permeable pipe (250). The sand-water mixture enters the sand-water output channel (240) through the sand-permeable pipe (250) and is discharged, thereby gradually reducing the amount of sedimented sea sand inside the corresponding particle ballast assembly (200).

[0117] (4) As the deposited sea sand in the particle ballast assembly (200) is discharged, the total particle ballast of the pipeline support body (100) decreases.

[0118] (5) The buoyancy adjustment component (300) is then inflated. As the buoyancy adjustment component (300) is inflated, the buoyancy of the pipeline support body (100) increases. This, combined with the reduction in self-weight caused by sand removal, further reduces the contact load of the pipeline support body (100) on the seabed, gradually changing it from a stable bottom-sitting state to a state that facilitates position adjustment. Subsequently, existing hoisting, towing, or deployment equipment used in deep-sea construction is used to adjust its position.

[0119] (6) After moving the pipeline support body (100) to the newly determined placement position, according to the new bottom position and attitude, the mixture of sea sand and seawater is fed into the particle ballast assembly (200) again through the corresponding sand and water input channel (230) to cause the sea sand to redeposit and increase the particle ballast.

[0120] (7) After completing the above adjustments, the pipeline support body (100) is lowered back down and placed in the predetermined position. After it is re-seated and its position and posture are confirmed to meet the construction requirements, the deep-sea pipeline is lowered, buffered, and gradually seated in accordance with the method described in the fourth embodiment.

Claims

1. A deep-sea pipeline foundation module for reversible particle ballast attitude adjustment, characterized in that, include: The pipeline support body (100), a plurality of particle ballast assemblies (200) disposed on the side of the pipeline support body (100), a buoyancy adjustment assembly (300) disposed inside the pipeline support body (100), and a detection assembly (400) disposed on the upper end of the particle ballast assembly (200). Multiple granular ballast assemblies (200) are distributed at different positions on the pipeline support body (100), and each granular ballast assembly (200) can respectively input and discharge sea sand; the buoyancy adjustment assembly (300) is used to adjust the buoyancy of the pipeline support body (100), and the detection assembly (400) is used to detect the underwater attitude state of the pipeline support body (100); the pipeline support body (100) forms a support area for receiving deep-sea pipelines, the buoyancy adjustment assembly (300) is disposed on the inner wall of the support area, and is used to adjust the buoyancy of the pipeline support body (100) during the sinking stage of the pipeline support body (100), and remains on the inner wall of the support area after the pipeline support body (100) touches the bottom, so as to receive the subsequently lowered deep-sea pipelines; The particle ballast assembly (200) includes several drainage holes (210), a sand and water input channel (230), a sand and water output channel (240), a sand-permeable pipe (250), and a sand-flushing pipe (260). The sand and water input channel (230), the sand and water output channel (240), and the sand-flushing pipe (260) are respectively connected to the interior of the particle ballast assembly (200), and the sand-permeable pipe (250) is connected to the sand and water output channel (240). The mixture of sea sand and seawater enters the particle ballast assembly (200) through the sand-water input channel (230). The sea sand settles and remains inside the particle ballast assembly (200), and excess seawater is discharged through the drain hole (210) to increase the particle ballast at the corresponding position. The flushing water enters the particle ballast assembly (200) through the sand flushing pipe (260) to resuspend the sea sand deposited inside the particle ballast assembly (200). The resulting sand-water mixture is discharged through the sand permeation pipe (250) and the sand-water output channel (240) to reduce the particle ballast at the corresponding position. By adjusting the particle ballast in the particle ballast assembly (200) at different positions, the self-weight and mass distribution of the pipeline support body (100) are changed, causing the pipeline support body (100) to sink under the combined action of its own weight and buoyancy. The underwater attitude of the pipeline support body (100) is adjusted by changing the position of the center of gravity.

2. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 1, characterized in that: The sand-permeable pipe (250) includes a track wire (251), a pipe opening baffle (252), and a spring pipe (253); the track wire (251) extends into the particle ballast assembly (200) and is used to limit the extension path of the spring pipe (253), the spring pipe (253) is extendable along the extension direction of the track wire (251), and the pipe opening baffle (252) is disposed at the sand inlet end of the spring pipe (253); the spring pipe (253) has the function of extending its sand inlet end along the track wire (251) toward the surface of the sea sand layer. The elastic restoring force of the pipe opening (252) causes the pipe opening to contact the surface of the sea sand layer and restrict the extension position of the spring pipe (253). As the sea sand is discharged through the sand-permeable pipe (250) and the height of the sea sand layer decreases, the limiting position of the pipe opening (252) decreases accordingly. Under the action of its own elastic restoring force, the spring pipe (253) continues to extend along the track wire (251), so that the sand inlet end of the spring pipe (253) moves with the decrease of the height of the sea sand layer surface, so that the sand inlet end is continuously kept at the surface of the sea sand layer and the sea sand is extracted.

3. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 1, characterized in that: Multiple particle ballast components (200) are respectively disposed on opposite sides of the pipeline support body (100). By inputting or discharging sea sand into the particle ballast components (200) on opposite sides, a particle ballast difference is formed on both sides of the pipeline support body (100) to change the mass distribution and center of gravity position of the pipeline support body (100) so as to achieve the attitude adjustment of the pipeline support body (100).

4. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 1, characterized in that: The particle ballast assembly (200) also includes a water turbine valve (270), which is located at the outlet end of the sand flushing pipe (260) and is used to spray the flushing water transported through the sand flushing pipe (260) into the particle ballast assembly (200) in multiple directions to expand the range of disturbance of the flushing water on the sedimented sea sand.

5. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 1, characterized in that: The particle ballast assembly (200) also includes a reinforced flange (220), which is disposed at the connection between the sand and water inlet channel (230) and the particle ballast assembly (200) to strengthen the connection between the sand and water inlet channel (230) and the particle ballast assembly (200).

6. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 1, characterized in that: The cross-section of the support area is an inverted trapezoid with a wider top and a narrower bottom; the buoyancy adjustment component (300) is an airbag with a buffer pad integrated and is respectively set on the two opposite inner sidewalls of the support area, and the buoyancy adjustment component (300) maintains the same installation position during the sinking stage of the pipeline support body (100) and the deep-sea pipeline support stage after landing.

7. The deep-sea pipeline foundation module with reversible particle ballast attitude adjustment according to claim 6, characterized in that: After the pipeline support body (100) touches the bottom, the buoyancy adjustment components (300) on both sides continue to be held on the two inner sidewalls of the support area and remain in an inflated state capable of supporting the deep-sea pipeline. The buoyancy adjustment components (300) on both sides jointly support the deep-sea pipeline lowered into the support area and gradually reduce the support height of the deep-sea pipeline by venting air, so that the deep-sea pipeline gradually descends along the support area to the predetermined support position. The buoyancy adjustment components (300) on both sides can vent air separately to adjust the attitude of the deep-sea pipeline during the lowering process by changing the support height on both sides.

8. The deep-sea pipeline foundation module for reversible particle ballast attitude adjustment according to claim 3, characterized in that: The detection component (400) is used to detect the underwater attitude state of the pipeline support body (100). The detected underwater attitude state is used to determine the particle ballast component (200) that needs to be input or discharged with sea sand, and to determine the change in particle ballast at the corresponding position. The underwater attitude of the pipeline support body (100) is corrected by changing the amount of sea sand deposited at the corresponding position and the resulting mass distribution.

9. A method for deep-sea pipeline foundation construction and pipeline lowering using a reversible particle ballast attitude adjustment deep-sea pipeline foundation module, characterized in that, Includes the following steps: S1, the deep-sea pipeline foundation module is launched into the water, and the buoyancy adjustment component (300) is inflated; S2, a mixture of sea sand and seawater is supplied to multiple granular ballast assemblies (200) respectively, so that the sea sand enters the interior of the granular ballast assembly (200) through the sand-water input channel (230) and settles, and the excess seawater is discharged through the drain hole (210). By increasing the granular ballast of multiple granular ballast assemblies (200), the pipeline support body (100) sinks. S3, during the sinking process of the pipeline support body (100), the underwater attitude state of the pipeline support body (100) is detected by the detection component (400). According to the detected underwater attitude state, the amount of sea sand in the particle ballast component (200) at different positions is adjusted to change the mass distribution and center of gravity position of the pipeline support body (100), thereby adjusting the underwater attitude of the pipeline support body (100). The sinking state of the pipeline support body (100) is adjusted by adjusting the inflation state of the buoyancy adjustment component (300). S4, adjust the particle ballast amount of the multiple particle ballast components (200) and the inflation state of the buoyancy adjustment component (300) so that the pipeline support body (100) sinks and sits on the seabed in a predetermined posture. After the pipeline support body (100) sits on the seabed, the buoyancy adjustment component (300) continues to be set on the inner wall of the support area and maintains the inflation state to support the deep-sea pipeline. S5, after the pipeline support body (100) is placed on the seabed, the deep-sea pipeline is lowered into the support area, so that the deep-sea pipeline comes into contact with the buoyancy adjustment component (300) set in the side wall of the support area, and the buoyancy adjustment component (300) buffers and supports the deep-sea pipeline. S6, gradually vent the buoyancy adjustment component (300) to gradually reduce its support height for the deep-sea pipeline, so that the deep-sea pipeline gradually descends along the support area to the predetermined support position.

10. The method for deep-sea pipeline foundation construction and pipeline lowering according to claim 9, characterized in that: Before the deep-sea pipeline is lowered, when the pipeline support body (100) needs to be adjusted after being placed on the seabed, flushing water is introduced into the corresponding particle ballast assembly (200) through the sand flushing pipe (260) to resuspend the deposited sea sand. The resulting sand-water mixture is discharged through the sand permeation pipe (250) and the sand-water output channel (240). During sand discharge, the sand inlet end of the sand permeation pipe (250) changes position as the sea sand layer surface decreases to reduce the size of the pipeline support body (100). The particle ballast load is increased; at the same time or subsequently, the buoyancy adjustment component (300) is inflated to increase the buoyancy of the pipeline support body (100) and reduce its contact load on the seabed, so that it changes from a stable bottoming state to a reduced load state, so as to adjust the deployment position; after the deployment position is re-determined, sea sand is input into the corresponding particle ballast component (200) again, and the inflation state of the buoyancy adjustment component (300) is adjusted so that the pipeline support body (100) sinks again and sits in the predetermined position.

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