Recyclable negative pressure group cabin passive sinking device, large diameter cylinder foundation construction and design method

Abstract

This invention relates to the field of marine engineering foundation design and construction technology, and particularly to a reusable negative pressure cabin passive sinking device, a construction and design method for large-diameter cylindrical foundations. The negative pressure cabin group comprises multiple negative pressure chambers; a force transmission structure is disposed inside the negative pressure chambers, including a matching first connecting part and a second connecting part. The first connecting part and the second connecting part form a unidirectional sliding constraint fit, whereby the first connecting part can apply downward pressure to the second connecting part, and the negative pressure chamber can drive the first connecting part to slide vertically relative to the second connecting part and detach from it. The reusable negative pressure cabin passive sinking device provided by this invention breaks through the limitation of traditional combined foundations where "auxiliary cabins are permanently welded and bound to the main cylinder," completely transforming the negative pressure cabin group into a "construction tool" rather than a "permanent structure." For large-scale foundation construction, it can significantly reduce the material usage of a single foundation, demonstrating extremely significant cost reduction, efficiency improvement, and environmental protection value.

Description

Technical Field

[0001] This invention relates to the field of marine engineering basic design and construction technology, and in particular to a reusable negative pressure group passive sinking device, a large-diameter cylindrical foundation construction and design method. Background Technology

[0002] Large-diameter cylindrical foundations (diameter ≥ 15m) have been widely used in marine engineering projects such as offshore wind power, floating oil and gas platform anchoring systems, and artificial island retaining structures due to their core advantages such as strong adaptability to geological formations, mature manufacturing technology, and convenient construction process.

[0003] However, as marine engineering advances towards deep-sea and large-scale operations, the traditional sinking construction of large-diameter cylindrical foundations faces severe technical bottlenecks. Specifically: First, relying on large, linked hammers for active vibration sinking results in intense vibrations that significantly disturb the seabed soil, easily leading to soil liquefaction, weakening the foundation's bearing capacity after completion, and even causing structural instability. Second, using pure negative pressure sinking with a single cylindrical body increases the required sinking driving force dramatically when the cylinder diameter is too large. Excessively high negative pressure values ​​can easily disrupt the force balance of the soil inside the cylinder, causing soil plug heave or piping failure.

[0004] To overcome the difficulties of sinking a single main cylinder, the industry has proposed an auxiliary sinking scheme using a "combined foundation." This involves permanently welding an outer skirt cabin to the outside of the main cylinder, using the combined cabins to provide additional negative pressure to assist in sinking. However, this fixed combined foundation has significant economic drawbacks: once sunk to the correct position, thousands of tons of steel structure for the skirt cabin, originally intended only for "auxiliary construction," will be permanently buried in the seabed, resulting in enormous steel waste and exorbitant costs. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the "combined foundation" auxiliary sinking scheme in the background technology, in which once the "combined foundation" is sunk into place, the skirt cabin steel structure, which was originally only used for "auxiliary construction", will be permanently buried in the seabed, resulting in great material waste and high cost. The invention provides a recyclable negative pressure cabin passive sinking device, a large-diameter cylinder foundation, a construction method for the large-diameter cylinder foundation, and a design method for the large-diameter cylinder foundation.

[0006] In a first aspect, the present invention provides a reusable negative pressure cabin passive sinking device, comprising:

[0007] The negative pressure group (2) includes multiple negative pressure chambers (20) arranged circumferentially. The force transmission structure (3) is disposed inside the negative pressure chamber (20). The force transmission structure (3) includes a matching first connecting part and a second connecting part. The first connecting part is connected to the inner wall of the negative pressure chamber (20). The first connecting part and the second connecting part form a one-way sliding constraint fit. The first connecting part can apply downward pressure to the second connecting part, and the negative pressure chamber (20) can drive the first connecting part to slide vertically relative to the second connecting part and separate from it.

[0008] This invention provides a recyclable negative pressure cabin passive sinking device, which breaks through the limitations of the traditional combined foundation's "permanent welding and binding of auxiliary cabins to the main cylinder," and completely transforms the negative pressure cabin (2) into a "construction tool" rather than a "permanent structure." For example, in the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure cabin (20); in the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically detaches from the constraint. That is, after passive sinking into place, the negative pressure cabin (2) can be completely separated from the main cylinder and recycled to the sea surface for reuse. For large-scale foundation construction, such as offshore wind farm construction, this solution can reduce the material usage of a single foundation by several times, demonstrating extremely significant cost reduction, efficiency improvement, and green environmental protection value.

[0009] Preferably, the first connecting part includes a first L-shaped hook (31), and the second connecting part includes a second L-shaped hook (32), with the first L-shaped hook (31) and the second L-shaped hook (32) arranged in a relatively inverted manner. The above solution is simple and easy to construct. This invention innovatively adopts a relatively inverted L-shaped hook structure. This force transmission structure is a "fully open" rigid sliding guide rail, without any internal closed cavity, spring, or precision telescopic components. During the sinking and pulling process, the open mechanical boundary allows the intruding highly viscous marine mud to be directly squeezed out or cut off, completely eliminating the mechanical jamming problem caused by siltation from a physical structure perspective, ensuring an extremely high fault tolerance rate.

[0010] Preferably, the force transmission structure (3) includes a hook chamber (33) for fixing to the outer wall of the cylindrical foundation (1), the second connecting part includes a second L-shaped hook (32), and the inner wall of the hook chamber (33) includes an arc-shaped slide rail (34) extending along the height direction. The arc-shaped slide rail (34) and the second L-shaped hook (32) can slide out of the hook chamber (33) through sliding engagement. This invention innovatively adopts an L-shaped hook-arc slide rail engagement structure. This force transmission structure is a "fully open" rigid sliding guide rail, without any internal closed cavity, spring or precision telescopic components. During sinking and pulling, the open mechanical boundary allows the intruding highly viscous marine mud to be directly squeezed out or cut off, completely eliminating the mechanical jamming problem caused by siltation from a physical structure perspective, ensuring an extremely high fault tolerance rate.

[0011] Preferably, the negative pressure chamber (20) is provided with a valve (21) at the top, and the valve (21) can serve as a common channel for natural water discharge and negative pressure pumping.

[0012] In a second aspect, the present invention provides a large-diameter cylindrical foundation, including a cylindrical foundation (1) and a recyclable negative pressure group passive sinking device as described in the present invention, wherein multiple negative pressure chambers (20) are arranged around the outside of the cylindrical foundation (1), and the second connecting part array is fixed on the outer wall of the cylindrical foundation (1).

[0013] This invention provides a large-diameter cylindrical foundation that breaks through the limitations of traditional combined foundations where "auxiliary chambers and cylindrical foundations (1) are permanently welded together," transforming the negative pressure chambers (2) into "construction equipment" rather than "permanent structures." For example, in the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure chambers (20); in the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically detaches from the constraint. That is, after passive sinking and positioning, the negative pressure chambers (2) can be completely separated from the cylindrical foundation (1) and recycled to the sea surface for reuse. For large-scale foundation construction, such as offshore wind farm construction, this solution can reduce the material usage of a single foundation by several times, demonstrating extremely significant cost reduction, efficiency improvement, and green environmental protection value.

[0014] In a third aspect, the present invention provides a construction method for constructing a large-diameter cylindrical foundation as described in the present invention, comprising the following steps: S1. Assemble the cylindrical foundation (1) with the negative pressure chamber (20) as a whole through the force transmission structure (3), so that the first connecting part and the second connecting part are in the initial sliding fit state, open the valves (21) on all the negative pressure chambers (20), and lower the large diameter cylindrical foundation to the seabed until the large diameter cylindrical foundation can no longer sink naturally; S2. Connect the valves (21) on all negative pressure chambers (20) to the negative pressure pipeline, and simultaneously extract the water in each negative pressure chamber (20) through the negative pressure pipeline to keep the negative pressure in each negative pressure chamber (20) consistent. The downward driving force generated by the negative pressure chamber (20) is transmitted to the cylindrical foundation (1) through the one-way mechanical abutment between the first connection part and the second connection part, which drives the cylindrical foundation (1) to sink as a whole. S3. After the cylindrical foundation (1) sinks to the design depth, water is injected into the corresponding negative pressure chamber (20) in reverse through the valve (21) to pressurize it, so that the negative pressure chamber (20) generates positive pressure and obtains upward support and upward pulling force; the negative pressure chamber (20) slides upward relative to the cylindrical foundation (1), the first connecting part moves automatically relative to the second connecting part and disengages from each other, and the negative pressure chamber (20) is recovered.

[0015] The construction method described in this invention is used for constructing large-diameter cylindrical foundations as described in this invention. During construction, it overcomes the limitations of traditional combined foundations where "auxiliary chambers are permanently welded and bound to the main cylinder," completely transforming the negative pressure chambers (2) into "construction equipment" rather than a "permanent structure." In the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure chamber (20). In the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically detaches from the constraint. That is, after passive sinking and positioning, the negative pressure chambers (2) can be completely separated from the main cylinder and recycled back to the sea surface for reuse. For large-scale foundation construction, such as offshore wind farm construction, this solution can significantly reduce the amount of steel used in a single foundation, demonstrating extremely significant cost reduction, efficiency improvement, and green environmental protection value.

[0016] Preferably, the construction method of the present invention further includes S4. Grouting operation between the cylindrical foundation (1) and the side soil layer.

[0017] In a fourth aspect, the present invention provides a design method for designing a large-diameter cylindrical foundation as described in the present invention, comprising the following steps: A1. Determine the number of columns for the first connecting part. A2. And iteratively calculate the number of rows of the first connecting part based on the number of columns of the first connecting part; A3: Based on the number of columns of the first connecting part and the number of rows of the first connecting part after one iteration, iteratively calculate the total axial force value that the force transmission structure (3) needs to bear; A4: Based on the total axial force value required by the force transmission structure (3) and the number of rows of the first connection after one iteration, calculate the number of columns of the first connection after one iteration, and use the number of columns of the first connection as the number of columns of the first connection in A2. Then, loop A2-A4. When a single iteration calculation is completed, evaluate the column tolerance and row tolerance. If both are not 0 at the same time, return to A2 for the next iteration. If both are 0 at the same time, it is determined that the iteration has converged, and the final result is output as the final row and column parameters of the first connection.

[0018] Preferably, the second connecting portion is arranged in multiple rows and columns along the circumferential direction, and the number of rows and columns is consistent with that of the first connecting portion; the number of rows of the first connecting portion... m Column number n c Overall design axial total force transmission value F To establish a nonlinear coupling relationship, an iterative method is used to determine it: Let the number of iterations be... j The initial number of columns is set to n c(0) ; in the j In this iteration, the number of rows of the first connecting part m (j) Determine using the following formula:

[0019] in, H The height of the negative pressure group chamber (2); d 1 is the safety clearance between the upper and lower ends of the negative pressure group chamber (2) and the force transmission structure (3); s The spacing between rows of the force transmission structure (3); c The stress superposition reduction factor for the group hooks based on the local buckling control of the cylindrical wall of the cylindrical foundation (1); symbol This indicates rounding down. n c (j-1) In the first j-1 The number of columns in the first connecting part in the next iteration.

[0020] Preferably, the force transmission structure (3) in the first... j The total axial force required for the next iteration F (j) The additional end friction caused by the spatial volume of the force transmission structure (3) is calculated using the following formula:

[0021] in, K e This is the amplification factor for eccentric loads; K w For wave and hydrodynamic coefficients; D (1) Outer diameter of the cylindrical foundation; n The number of soil layers within the settlement depth range of the cylindrical foundation (1); or i This is the coefficient for weakening side friction resistance; t fi Let be the ultimate side friction resistance of the i-th soil layer; h i Let be the thickness of the i-th soil layer; l This is the end resistance reduction factor; q pa This refers to the soil's ultimate resistance. A b The bearing area at the bottom of the cylindrical foundation (1); r t The material density of the cylindrical foundation (1); V t The volume of the cylindrical foundation (1); r jThe density of the medium in which the cylindrical foundation (1) is located; V p The total volume of the medium immersed in the cylindrical foundation (1); g This is the acceleration due to gravity. Δf c The additional resistance generated by a single force-transmitting structure (3) in the soil penetration is calculated using the following formula:

[0022] in, or p This is the local end resistance reduction coefficient; q pa This refers to the soil's ultimate resistance. A c The horizontal projected area of ​​a single force-transmitting structure (3) in the penetration direction; or s This is the side drag reduction factor. t fi Let be the ultimate side friction resistance of the i-th soil layer; S ci For a single force transmission structure (3) in the first i The lateral surface area of ​​effective contact in the soil layer; r c The material density of the force transmission structure (3); r w The density of seawater or the mud-water mixture on the surface of the seabed; V c The real volume of a single force-transmitting structure (3); g This is the acceleration due to gravity.

[0023] Preferably, the number of force transmission structure rows on each negative pressure group chamber (2) n c (j) In the j-th iteration, the calculation is updated according to the following formula:

[0024] in, k The total number of reusable negative pressure cabins (2); m (j) Let the number of rows of the first connecting part be the number of rows in the j-th iteration. ， s The allowable compressive stress of the force transmission structure (3); A The effective bearing area of ​​a single force transmission structure (3) is represented by the symbol. This indicates rounding up to the nearest integer.

[0025] The design method provided by this invention not only offers a physical connection device, but also introduces a comprehensive design axial force formula that incorporates eccentric loads, hydrodynamic coefficients, and soil softening reduction.F Based on this rigorous mechanical foundation, a multi-row, multi-column array-type force transmission structure is adopted to evenly distribute the sinking resistance of hundreds of tons to each effective pressure-bearing surface of the large-diameter cylinder wall, eliminating the risk of local buckling of the cylinder wall or shearing of the force transmission structure (3) caused by single-point stress concentration, and truly possessing the value of guiding actual engineering construction under complex and harsh sea conditions.

[0026] Meanwhile, the above design method provides a design basis for the force transmission structure (3). In addition to ensuring the smooth and safe sinking of the large-diameter cylinder foundation by the passive sinking device of the recyclable negative pressure group chamber, it can also determine the optimal connection method based on the iteration results, so as to achieve a balance between safety and economy. That is, through the results of iterative calculation, a safety lower limit design scheme can be obtained, so as to know the safety bottom line conditions, to ensure safety, and to optimize on the basis of ensuring safety, so as to achieve a balance between safety and economy.

[0027] In a fourth aspect, the present invention provides a design method for designing a large-diameter cylindrical foundation as described in the present invention, comprising the following steps: B1. Based on the outer diameter of the cylindrical foundation (1), the number of soil layers within the settlement depth range of the cylindrical foundation (1), the bottom bearing area of ​​the cylindrical foundation (1), the volume of the cylindrical foundation (1), and the total volume of the medium immersed in the cylindrical foundation (1), the total axial force value required to be borne by the separated force transmission structure (3) is obtained. B2. Based on the total axial force value required to be borne by the separated force transmission structure (3), the number of rows and columns of the first and second connecting parts can be obtained; B3. The height of the negative pressure chamber (20) and the total number of negative pressure chambers (20) are obtained based on the number of rows and columns of the first and second connecting parts.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a recyclable negative pressure cabin passive sinking device, which breaks through the limitation of the traditional combined foundation "the auxiliary cabins are permanently welded and bound to the main cylinder", and completely transforms the negative pressure cabin (2) into a "construction tool" rather than a "permanent structure". For example, in the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection are mechanically abutted in the vertical direction to transmit the downward driving force generated by the negative pressure cabin (20); in the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it is physically separated from the constraint. That is, after passive sinking into place, the negative pressure cabin (2) can be completely separated from the main cylinder and recovered to the sea surface for recycling. For large-scale foundation construction, such as offshore wind farm construction, this solution can reduce the amount of steel used in a single foundation by a factor of two, showing extremely significant cost reduction, efficiency improvement and green environmental protection value. Attached Figure Description

[0029] Figure 1 This is a structural schematic diagram of a large-diameter cylindrical foundation according to this application (a negative pressure chamber is removed to clearly show the force transmission structure).

[0030] Figure 2 This is a schematic diagram of the fit between the cylindrical base and the second L-shaped hook in this application.

[0031] Figure 3 This is a schematic diagram of the negative pressure chamber and the first L-shaped hook of this application.

[0032] Figure 4 This is a structural schematic diagram of a large-diameter cylindrical foundation according to this application.

[0033] Figure 5 This is a schematic diagram of the negative pressure chamber of this application (with a hook chamber).

[0034] Figure 6 This is a schematic cross-sectional view of a large-diameter cylindrical foundation according to this application (with the second L-shaped hook and hook chamber in tandem).

[0035] Figure 7 For the purposes of this application Figure 6 Enlarged schematic diagram of part A in the middle.

[0036] Figure 8 This is a schematic cross-sectional view of a large-diameter cylindrical foundation according to this application (the second L-shaped hook and the first L-shaped hook are in tandem).

[0037] Figure 9 For the purposes of this application Figure 8 Enlarged schematic diagram of section B in the middle.

[0038] Figure 10 This is a schematic diagram showing the fit between the cylindrical foundation and the grouting pipe in this application.

[0039] Marked in the image: 1-Cylindrical foundation (1), 11-Grouting pipe (11). 2-Negative pressure group (2), 20-Negative pressure chamber (20), 21-Valve (21); 3-Force transmission structure (3), 31-First L-shaped hook (31), 32-Second L-shaped hook (32), 33-Hook compartment (33), 34-Arc-shaped slide (34). Detailed Implementation

[0040] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0041] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0042] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0043] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0044] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0045] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0046] Example 1 like Figure 1-10 As shown, this embodiment provides a recyclable negative pressure cabin passive sinking device, including a negative pressure cabin (2) and a force transmission structure (3).

[0047] In one or more embodiments, the negative pressure group (2) includes a plurality of negative pressure chambers (20) arranged circumferentially.

[0048] In one or more embodiments, a force transmission structure (3) is disposed inside the negative pressure chamber (20), the force transmission structure (3) including a matching first connecting part and a second connecting part, the first connecting part and the second connecting part being detachably connected.

[0049] In an optional embodiment, the first connecting part is connected to the inner wall of the negative pressure chamber (20), and the first connecting part and the second connecting part form a one-way sliding constraint fit. The first connecting part can apply downward pressure to the second connecting part, and the negative pressure chamber (20) can drive the first connecting part to slide vertically relative to the second connecting part and disengage from it.

[0050] In an optional embodiment, the first connection is welded to the inner wall of the negative pressure chamber (20).

[0051] This embodiment provides a recyclable negative pressure cabin passive sinking device that breaks through the limitations of the traditional combined foundation's "permanent welding and binding of auxiliary cabins and main cylinder", completely transforming the negative pressure cabin (2) into a "construction tool" rather than a "permanent structure". For example, in the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure cabin (20); in the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically breaks free from the restriction, that is, after passive sinking into place, the negative pressure cabin (2) can be completely separated from the main cylinder and recovered to the sea surface for recycling. For large-scale foundation construction, such as offshore wind farm construction, this solution can reduce the amount of steel used in a single foundation by several times, showing extremely significant cost reduction, efficiency improvement and green environmental protection value.

[0052] In recent years, the applicant has attempted to develop reusable auxiliary sinking devices to reduce costs. However, these attempts often rely on complex underwater hydraulic latches, telescopic locking tongues, or precision electrical release mechanisms. In the real deep-sea environment, highly viscous marine mud and fine suspended particles can easily penetrate these "closed" precision mechanical cavities, causing hydraulic cylinder jamming or electrical failure. Furthermore, complex moving parts are prone to permanent plastic deformation under enormous non-uniform earth pressure, eventually leading to "lock-in" and preventing the auxiliary device from detaching for recovery, resulting in major engineering accidents.

[0053] like Figure 8 and 9 As shown, in an optional embodiment, the recyclable negative pressure cabin passive sinking device described in this embodiment includes a first L-shaped hook (31) in the first connecting part and a second L-shaped hook (32) in the second connecting part, with the first L-shaped hook (31) and the second L-shaped hook (32) arranged in a relatively inverted manner. The above solution is simple and easy to construct. This invention innovatively adopts a relatively inverted L-shaped hook structure. This force transmission structure is a "fully open" rigid sliding guide rail, without any internal closed cavity, spring, or precision telescopic components. During the sinking and lifting process, the open mechanical boundary allows the intruding highly viscous marine mud to be directly squeezed out or cut off, completely eliminating the mechanical jamming problem caused by siltation from a physical structure perspective, ensuring an extremely high fault tolerance rate.

[0054] like Figure 6 and 7 As shown, in another optional embodiment, the recyclable negative pressure cabin passive sinking device described in this embodiment includes a force transmission structure (3) comprising a hook chamber (33) for fixing to the outer wall of the cylindrical foundation (1), a second connecting part comprising a second L-shaped hook (32), and an arc-shaped slide rail (34) extending along the height direction on the inner wall of the hook chamber (33). The arc-shaped slide rail (34) and the second L-shaped hook (32) can slide out of the hook chamber (33) through sliding engagement. This invention innovatively adopts an L-shaped hook-arc slide rail engagement structure. This force transmission structure is a "fully open" rigid sliding guide rail, without any internal closed cavity, spring, or precision telescopic components. During sinking and pulling up, the open mechanical boundary allows the intruding highly viscous marine mud to be directly squeezed out or cut off, completely eliminating the mechanical jamming problem caused by siltation from a physical structure perspective, ensuring an extremely high fault tolerance rate.

[0055] In one or more embodiments, the negative pressure chamber (20) is provided with a valve (21) at the top, which can serve as a common channel for natural water discharge and negative pressure pumping.

[0056] In one or more embodiments, a grouting pipe (11) is provided on the side wall of the cylindrical foundation (1), for example, by welding or integral molding. A grout outlet hole is provided on the lower side wall of the grouting pipe (11). When the negative pressure chamber (20) is recovered, grouting is performed using the gap in the lower side of the cylindrical foundation (1) through the grouting pipe (11) to improve the stability of the cylindrical foundation (1).

[0057] (1) Steel cylinder is preferred for cylindrical foundation.

[0058] Example 2 like Figure 1-10 As shown, this embodiment provides a large-diameter cylindrical foundation, including a cylindrical foundation (1) and a recyclable negative pressure group passive sinking device as described in Embodiment 1. Multiple negative pressure chambers (20) are arranged around the outside of the cylindrical foundation (1), and the second connecting part array is fixed on the outer wall of the cylindrical foundation (1).

[0059] In an optional embodiment, the second connecting part array is welded to the outer wall of the cylindrical foundation (1).

[0060] The large-diameter cylindrical foundation described in this embodiment includes a cylindrical foundation (1), multiple negative pressure chambers (20) arranged around the outer wall of the cylindrical foundation (1) to form a negative pressure group chamber (2), and a separate force transmission structure (3) arranged between the two; the force transmission structure (3) includes a second connecting part fixed in an array to the outer wall of the cylindrical foundation (1), and a first connecting part fixed to the side wall of the negative pressure group chamber (2) and matching the second connecting part; the first connecting part and the second connecting part form a one-way sliding constraint fit: in the sinking condition, the pressure surface of the first connecting part and the bearing surface of the second connecting part mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure group chamber (2); in the recovery condition, the bearing surface of the first connecting part can slide along the pressure surface of the second connecting part until it physically breaks free from the constraint.

[0061] The force transmission structure (3) preferably adopts an inverted L-shaped hook form, including a second L-shaped hook (32) fixed to the outer wall of the cylindrical foundation (1) and a first L-shaped hook (31) fixed to the inner wall of the negative pressure chamber (20); or adopts an L-shaped hook-slide form, that is, including a second L-shaped hook (32) fixed to the outer wall of the cylindrical foundation (1) and an arc-shaped slide (34) and hook compartment (33) extending along the height direction of the inner wall of the negative pressure chamber (2).

[0062] This embodiment provides a large-diameter cylindrical foundation that breaks through the limitations of traditional combined foundations where "auxiliary chambers and cylindrical foundations (1) are permanently welded together," transforming the negative pressure chambers (2) into "construction equipment" rather than "permanent structures." For example, in the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure chamber (20); in the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically detaches from the constraint. That is, after passive sinking and positioning, the negative pressure chambers (2) can be completely separated from the cylindrical foundation (1) and recycled to the sea surface for reuse. For large-scale foundation construction, such as offshore wind farm construction, this solution can reduce the material usage of a single foundation by several times, demonstrating extremely significant cost reduction, efficiency improvement, and green environmental protection value.

[0063] Example 3 This embodiment provides a construction method for constructing a large-diameter cylindrical foundation as described in Embodiment 2, comprising the following steps: S1. Assemble the cylindrical foundation (1) with the negative pressure chamber (20) through the force transmission structure (3) to form a whole, so that the first connecting part and the second connecting part are in the initial sliding fit state, open the valves (21) on all the negative pressure chambers (20), and lower the large diameter cylindrical foundation to the seabed until the cylindrical foundation (1) can no longer sink naturally; S2. Connect the valves (21) on all negative pressure chambers (20) to the negative pressure pipeline, and simultaneously extract the water in each negative pressure chamber (20) through the negative pressure pipeline to keep the negative pressure in each negative pressure chamber (20) consistent. The downward driving force generated by the negative pressure chamber (20) is transmitted to the cylindrical foundation (1) through the one-way mechanical abutment between the first connection part and the second connection part, which drives the cylindrical foundation (1) to sink as a whole. S3. After the cylindrical foundation (1) sinks to the design depth, water is injected into the negative pressure chamber (20) in reverse through the valve (21) to pressurize it, so that positive pressure is generated inside the negative pressure chamber (20) and an upward supporting force and upward pulling force are obtained; the negative pressure chamber (20) slides upward relative to the cylindrical foundation (1), the first connecting part moves automatically relative to the second connecting part and disengages from each other, and the negative pressure chamber (20) is recovered.

[0064] The construction method described in this invention is used for constructing large-diameter cylindrical foundations as described in this invention. During construction, it overcomes the limitations of traditional combined foundations where "auxiliary chambers are permanently welded and bound to the main cylinder," completely transforming the negative pressure chambers (2) into "construction equipment" rather than a "permanent structure." In the sinking condition, the pressure-bearing surface of the first connection and the bearing surface of the second connection mechanically abut in the vertical direction to transmit the downward driving force generated by the negative pressure chamber (20). In the recovery condition, the bearing surface of the second connection can slide relative to the first connection until it physically detaches from the constraint. That is, after passive sinking and positioning, the negative pressure chambers (2) can be completely separated from the main cylinder and recycled back to the sea surface for reuse. For large-scale foundation construction, such as offshore wind farm construction, this solution can significantly reduce the amount of steel used in a single foundation, demonstrating extremely significant cost reduction, efficiency improvement, and green environmental protection value.

[0065] In one or more embodiments, S4 is also included. Grouting is performed between the cylindrical foundation (1) and the side soil layer via the grouting pipe (11).

[0066] In a preferred embodiment, the construction method described in this example, based on the passive sinking of a cylindrical foundation (1) of a recyclable negative pressure chamber, preferably includes the following steps: Step 1: Assemble the cylindrical foundation (1) and the negative pressure chamber (2) so that the force transmission structure (3) is in the initial sliding fit state. Open all chamber valves (21) and slowly lower the foundation to the seabed using the hoisting equipment until it can no longer sink naturally. Step 2: Connect all the negative pressure pipelines of the group chambers to the group chamber valves (21), start the negative pressure system to synchronously extract the water in the negative pressure group chambers (2), keep the negative pressure in each negative pressure group chamber consistent, and the downward driving force generated by the negative pressure group chambers is effectively transmitted to the cylindrical foundation (1) through the one-way mechanical contact of the force transmission structure (3), which drives it to sink as a whole. Step 3: After the cylindrical foundation (1) sinks to the design depth, the negative pressure system uses valve (21) to inject water into the negative pressure group chamber (2) in reverse to pressurize it, so that the inside of the group chamber generates positive pressure and obtains upward support and upward pulling force; since the force transmission structure (3) is a one-way sliding constraint fit, the negative pressure group chamber (2) slides upward relative to the cylindrical foundation (1), and the force transmission structure automatically unlocks and disengages, realizing the recycling of the negative pressure group chamber (2).

[0067] Example 4 This embodiment discloses a design method, characterized by the following steps for designing a large-diameter cylindrical foundation as described in Embodiment 2: A1. Determine the number of columns for the first connecting part. A2. And iteratively calculate the number of rows of the first connecting part based on the number of columns of the first connecting part; A3: Based on the number of columns of the first connecting part and the number of rows of the first connecting part after one iteration, iteratively calculate the total axial force value that the force transmission structure (3) needs to bear; A4: Based on the total axial force value required by the force transmission structure (3) and the number of rows of the first connection after one iteration, calculate the number of columns of the first connection after one iteration, and use the number of columns of the first connection as the number of columns of the first connection in A2. Then, loop A2-A4. When a single iteration calculation is completed, evaluate the column tolerance and row tolerance. If both are not 0 at the same time, return to A2 for the next iteration. If both are 0 at the same time, it is determined that the iteration has converged, and the final result is output as the final row and column parameters of the first connection.

[0068] In one or more embodiments, the above steps are preferably as follows: The first connecting part (31) on the inner wall of the negative pressure group chamber (2) is arranged in multiple rows and columns along the circumference, with the number of rows consistent with the number of rows in the second connecting part (32), and the total number of columns also consistent; considering the additional soil discharge resistance caused by the penetration of the force transmission structure into the soil and the superposition effect of the group hook stress, its number of rows m Column number n c Overall design axial total force transmission value F To establish a nonlinear coupling relationship, an iterative method must be used to determine it: Let the number of iterations be... j The initial number of columns is set to n c (0) ; in the j In the next iteration, the number of rows m (j) Determine using the following formula:

[0069] in, H The height of the negative pressure group chamber (2); d 1 is the safety clearance between the upper and lower ends of the negative pressure group chamber (2) and the force transmission structure (3), which is generally 0.1-0.3m; s The spacing between rows of the force transmission structure; c For the group hook stress superposition reduction factor based on the local buckling control of the cylindrical wall of the cylindrical foundation (1), it is recommended that the value be between 0.02 and 0.15. A larger value should be used if the penetration resistance is large, and a smaller value should be used otherwise; symbol This indicates rounding down to the nearest integer.

[0070] To meet the force transmission requirements for sinking, the separated force transmission structure (3) in the first... j The total axial force required for the next iteration F (j)The additional end friction caused by the spatial volume of the force transmission structure itself is calculated using the following formula:

[0071] in, K e For the eccentric load amplification factor, it is recommended to take a value of 1.2-1.5; K w For wave and hydrodynamic coefficients, a value of 1.1-1.3 is recommended; D (1) Outer diameter of the cylindrical foundation; n The number of soil layers within the settlement depth range of the cylindrical foundation (1); or i This is the side friction weakening coefficient, which is generally taken as 0.6-0.9; t fi For the first i Ultimate side friction of the soil layer; h i For the first i The thickness of the soil layer; l This is the end resistance reduction factor, typically taken as 0.4-0.8; q pa This refers to the soil's ultimate resistance. A b The bearing area at the bottom of the cylindrical foundation (1); r t The material density of the cylindrical foundation (1); V t The volume of the cylindrical foundation (1); r j The density of the medium in which the cylindrical foundation (1) is located; V p The total volume of the immersion medium for the cylindrical foundation (1) is calculated based on the actual sinking depth. g This is the acceleration due to gravity. Δ f c The additional resistance generated by a single force-transmitting structure in the soil is calculated using the following formula:

[0072] in, A c The horizontal projected area of ​​a single force-transmitting structure (3) in the penetration direction; S ci For a single force transmission structure (3) in the first i The lateral surface area of ​​effective contact in the soil layer; V c The real volume of a single force-transmitting structure (3); r c The material density of the force transmission structure (3); r w The density of seawater or a mixture of seawater and muddy water on the surface of the seabed; or p The end resistance reduction coefficient is 0.6~0.8. Since the force transmission structure is close to the outer wall of the cylindrical foundation (1), the end resistance is reduced compared with the independent structure due to the "stress shielding effect" of the large volume of soil discharge of the cylindrical foundation. or s This is the side resistance reduction factor. Considering the lubrication effect of the boundary layer mud, a value of 0.4 to 0.7 is recommended.

[0073] Number of force transmission structure columns on each negative pressure group chamber (2) n c (j) In the j In the next iteration, the calculation is updated according to the following formula:

[0074] in, k The total number of reusable negative pressure cabins (2); s is the allowable compressive stress of the force transmission structure (3); A is the effective bearing area of ​​a single force transmission structure (3), which is the horizontal bearing surface where the two metal hooks contact and press against each other. Symbol This indicates rounding up to the nearest integer.

[0075] After completing a single iteration, evaluate the column tolerance. n c (j) - n c (j-1) |Row Tolerance| m (j) - m (j-1) |; If neither of them is 0 at the same time, then let j = j +1 and return to claim (3) for the next iteration; if both are 0, the iteration is considered converged, and the system outputs the final value. m (j) and n c (j) As parameters for the final number of rows and columns of the force transmission structure.

[0076] The design method provided by this invention not only offers a physical connection device, but also introduces a comprehensive design axial force formula that incorporates eccentric loads, hydrodynamic coefficients, and soil softening reduction. FBased on this rigorous mechanical foundation, a multi-row, multi-column array-type force transmission structure is adopted to evenly distribute the sinking resistance of hundreds of tons to each effective pressure-bearing surface of the large-diameter cylinder wall, eliminating the risk of local buckling of the cylinder wall or shearing of the force transmission structure (3) caused by single-point stress concentration, and truly possessing the value of guiding actual engineering construction under complex and harsh sea conditions.

[0077] The design method provided in this embodiment not only provides a physical connection device, but also provides a design basis for the force transmission structure (3). In addition to ensuring the smooth and safe sinking of the large-diameter cylinder foundation by the recyclable negative pressure group chamber passive sinking device, it can also determine the optimal connection method based on the iteration results, thereby achieving a balance between safety and economy. That is, through the results of iterative calculation, a safety lower limit design scheme can be obtained, so as to know the safety bottom line conditions, to ensure safety, and to optimize on the basis of ensuring safety, thereby achieving a balance between safety and economy.

[0078] Example 5 This embodiment discloses a design method, characterized in that it is used to design a large-diameter cylindrical foundation as described in Embodiment 2, and includes the following steps: B1. Based on the outer diameter of the cylindrical foundation (1), the number of soil layers within the settlement depth range of the cylindrical foundation (1), the bottom bearing area of ​​the cylindrical foundation (1), the volume of the cylindrical foundation (1), and the total volume of the medium immersed in the cylindrical foundation (1), the total axial force value required to be borne by the separated force transmission structure (3) is obtained. B2. Based on the total axial force value required to be borne by the separated force transmission structure (3), the number of rows and columns of the first and second connecting parts can be obtained; B3. The height of the negative pressure chamber (20) and the total number of negative pressure chambers (20) are obtained based on the number of rows and columns of the first and second connecting parts.

[0079] The negative pressure group chamber (2) is equipped with a group chamber valve (21) at the top centroid, which serves as a common channel for natural water discharge and negative pressure pumping. It is connected to the external negative pressure system through an independent group chamber negative pressure pipeline.

[0080] The design method described in this embodiment is simpler and can more quickly calculate and estimate the number of columns, rows and the total number of negative pressure chambers (20) of the force transmission structure, but its accuracy is not high and it is more often used in estimation situations.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A recyclable negative pressure cabin passive sinking device, characterized in that, include: The negative pressure group (2) includes multiple negative pressure chambers (20) arranged circumferentially. The force transmission structure (3) is disposed inside the negative pressure chamber (20). The force transmission structure (3) includes a matching first connecting part and a second connecting part. The first connecting part is connected to the inner wall of the negative pressure chamber (20). The first connecting part and the second connecting part form a one-way sliding constraint fit. The first connecting part can apply downward pressure to the second connecting part, and the negative pressure chamber (20) can drive the first connecting part to slide vertically relative to the second connecting part and separate from it.

2. The reusable negative pressure multi-chamber passive sinking device according to claim 1, characterized in that, The first connecting part includes a first L-shaped hook (31), and the second connecting part includes a second L-shaped hook (32). The first L-shaped hook (31) and the second L-shaped hook (32) are arranged opposite to each other. or, The force transmission structure (3) includes a hook chamber (33) for fixing to the outer wall of the cylindrical foundation (1), the second connecting part includes a second L-shaped hook (32), the inner wall of the hook chamber (33) includes an arc-shaped slide (34) extending along the height direction, the arc-shaped slide (34) and the second L-shaped hook (32) can slide out of the hook chamber (33) by sliding engagement.

3. The reusable negative pressure multi-chamber passive sinking device according to claim 1, characterized in that, The negative pressure chamber (20) is equipped with a valve (21) at the top, which can serve as a common channel for natural water discharge and negative pressure pumping.

4. A large-diameter cylindrical foundation, characterized in that, It includes a cylindrical foundation (1) and a recyclable negative pressure group passive sinking device as described in any one of claims 1-3, wherein multiple negative pressure chambers (20) are arranged around the outside of the cylindrical foundation (1), and the second connecting part array is fixed on the outer wall of the cylindrical foundation (1).

5. A construction method, characterized in that, The method for constructing a large-diameter cylindrical foundation as described in claim 4 includes the following steps: S1. Assemble the cylindrical foundation (1) with the negative pressure chamber (20) through the force transmission structure (3) to form a whole, so that the first connecting part and the second connecting part are in the initial sliding fit state, open the valves (21) on all the negative pressure chambers (20), and lower the large diameter cylindrical foundation to the seabed until the cylindrical foundation (1) can no longer sink naturally; S2. Connect the valves (21) on all the negative pressure chambers (20) to the negative pressure pipeline, and simultaneously extract the water in each negative pressure chamber (20) through the negative pressure pipeline. The downward driving force generated by the negative pressure chamber (20) is transmitted to the cylindrical foundation (1) through the one-way mechanical abutment between the first connection part and the second connection part, which drives the cylindrical foundation (1) to sink as a whole. S3. After the cylindrical foundation (1) sinks to the design depth, water is injected into the negative pressure chamber (20) in reverse through the valve (21) to pressurize it, so that positive pressure is generated inside the negative pressure chamber (20) and an upward supporting force and upward pulling force are obtained; the negative pressure chamber (20) slides upward relative to the cylindrical foundation (1), the first connecting part moves automatically relative to the second connecting part and disengages from each other, and the negative pressure chamber (20) is recovered.

6. A construction method according to claim 5, characterized in that, It also includes S4. Grouting operation between the cylindrical foundation (1) and the side soil layer.

7. A design method, characterized in that, The method for designing a large-diameter cylindrical foundation as described in claim 4 includes the following steps: A1. Determine the number of columns for the first connecting part. A2. And iteratively calculate the number of rows of the first connecting part based on the number of columns of the first connecting part; A3: Based on the number of columns of the first connecting part and the number of rows of the first connecting part after one iteration, iteratively calculate the total axial force value that the force transmission structure (3) needs to bear; A4: Based on the total axial force value required by the force transmission structure (3) and the number of rows of the first connection after one iteration, calculate the number of columns of the first connection after one iteration, and use the number of columns of the first connection as the number of columns of the first connection in A2. Then, loop A2-A4. When a single iteration calculation is completed, evaluate the column tolerance and row tolerance. If both are not 0 at the same time, return to A2 for the next iteration. If both are 0 at the same time, it is determined that the iteration has converged, and the final result is output as the final row and column parameters of the first connection.

8. The design method according to claim 7, characterized in that, The second connecting part is arranged in multiple rows and columns along the circumference, with the number of rows and columns consistent with the first connecting part; the number of rows of the first connecting part... m Column number n c Overall design axial total force transmission value F To establish a nonlinear coupling relationship, an iterative method is used to determine it: Let the number of iterations be... j The initial number of columns is set to n c (0) ; in the j In this iteration, the number of rows of the first connecting part m (j) Determine using the following formula: in, H The height of the negative pressure group chamber (2); δ 1 is the safety clearance between the upper and lower ends of the negative pressure group chamber (2) and the force transmission structure (3); s The spacing between rows of the force transmission structure (3); γ The stress superposition reduction factor for the group hooks based on the local buckling control of the cylindrical wall of the cylindrical foundation (1); symbol This indicates rounding down. n c (j-1) In the first j-1 The number of columns in the first connecting part in the next iteration.

9. The design method according to claim 7, characterized in that, The force transmission structure (3) in the first j The total axial force required for the next iteration F (j) The additional end friction caused by the spatial volume of the force transmission structure (3) is calculated using the following formula: in, K e This is the amplification factor for eccentric loads; K w For wave and hydrodynamic coefficients; D (1) Outer diameter of the cylindrical foundation; n The number of soil layers within the settlement depth range of the cylindrical foundation (1); η i This is the coefficient for weakening side friction resistance; τ fi Let be the ultimate side friction resistance of the i-th soil layer; h i Let be the thickness of the i-th soil layer; λ This is the end resistance reduction factor; q pa This refers to the soil's ultimate resistance. A b The bearing area at the bottom of the cylindrical foundation (1); ρ t The material density of the cylindrical foundation (1); V t The volume of the cylindrical foundation (1); ρ j The density of the medium in which the cylindrical foundation (1) is located; V p The total volume of the medium immersed in the cylindrical foundation (1); g This is the acceleration due to gravity. Δf c The additional resistance generated by a single force-transmitting structure (3) in the soil penetration is calculated using the following formula: in, η p This is the local end resistance reduction coefficient; q pa This refers to the soil's ultimate resistance. A c The horizontal projected area of ​​a single force-transmitting structure (3) in the penetration direction; η s This is the side drag reduction factor. τ fi Let be the ultimate side friction resistance of the i-th soil layer; S ci For a single force transmission structure (3) in the first i The lateral surface area of ​​effective contact in the soil layer; ρ c The material density of the force transmission structure (3); ρ w The density of seawater or the mud-water mixture on the surface of the seabed; V c The real volume of a single force-transmitting structure (3); g It is the acceleration due to gravity; Number of force transmission structure columns on each negative pressure group chamber (2) n c (j) In the j-th iteration, the calculation is updated according to the following formula: in, k The total number of reusable negative pressure cabins (2); m (j) Let the number of rows of the first connecting part be the number of rows in the j-th iteration. , σ The allowable compressive stress of the force transmission structure (3); A The effective bearing area of ​​a single force transmission structure (3) is represented by the symbol. This indicates rounding up to the nearest integer.

10. A design method, characterized in that, The method for designing a large-diameter cylindrical foundation as described in claim 4 includes the following steps: B1. Based on the outer diameter of the cylindrical foundation (1), the number of soil layers within the settlement depth range of the cylindrical foundation (1), the bottom bearing area of ​​the cylindrical foundation (1), the volume of the cylindrical foundation (1), and the total volume of the medium immersed in the cylindrical foundation (1), the total axial force value required to be borne by the separated force transmission structure (3) is obtained. B2. Based on the total axial force value required to be borne by the separated force transmission structure (3), the number of rows and columns of the first and second connecting parts can be obtained; B3. The height of the negative pressure chamber (20) and the total number of negative pressure chambers (20) are obtained based on the number of rows and columns of the first and second connecting parts.

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