WO2023169244A1

WO2023169244A1 - Gravity pile shoe capable of bearing lateral load effect

Info

Publication number: WO2023169244A1
Application number: PCT/CN2023/078569
Authority: WO
Inventors: 渠基顺; 谷家扬; 韦琪; 王丽元; 王秋平; 胡方鑫
Original assignee: 江苏科技大学; 江苏科技大学海洋装备研究院
Priority date: 2022-03-10
Filing date: 2023-02-28
Publication date: 2023-09-14
Also published as: CN114541379A; CN114541379B

Abstract

The present invention relates to a gravity pile shoe capable of bearing a lateral load effect, comprising a mounting base, an anti-lateral motion portion and a pressure reducing portion. The mounting base is assembled at the lower free end of an offshore platform pile leg. The anti-lateral motion portion is formed from multiple inserting columns which are directly borne by the mounting base and may be deeply inserted below a seabed bearing layer. The pressure reducing portion comprises a top contact bottom plate and an auxiliary connecting unit. The top contact bottom plate is arranged parallel to and directly below the mounting base, and a clearance gap allowing an inserting column to freely pass through is provided on the top contact bottom plate. The auxiliary connecting unit is formed from multiple sets of linkage mechanisms which are connected between the mounting base and the top contact bottom plate, and are uniformly distributed around the periphery of the anti-lateral motion portion. After the offshore platform pile leg completes final sinking construction, the inserting column is deeply inserted into the bearing layer, so that the pile shoe has good lateral force resistance, thereby ensuring that the ocean platform meets the requirements for resisting horizontal impact loads, which means that the risk of lateral motion is reduced when it is subjected to a series of horizontal loads such as wind, waves, and ocean currents.

Description

A gravity-type spud shoe that can withstand lateral loads

Technical field

The invention relates to the technical field of offshore platform manufacturing, in particular to a gravity-type spud shoe that can withstand lateral loads.

Background technique

The spud shoe is an important structure of the self-elevating offshore platform. It is used as a connection transition between the offshore platform leg and the seabed, and transfers the environmental load on the leg and the self-weight load of the offshore platform to the seabed, thereby improving the offshore platform. Stability when impacted by ocean currents.

In practical applications, the pile boots are not only subject to the downward pressure from the deadweight load of the offshore platform, but are also bound to be subject to a series of horizontal loads such as wind, waves, and ocean currents. However, the existing design only considers the structural stability of the spud shoe when it is subjected to downward pressure. For example: Chinese invention patent CN201110084096.0 discloses a retractable drilling platform spud shoe structure, which includes a top plate and a bottom plate. , telescopic steel frame, movable spud shoe side wall shell and hydraulic device. Another example: Chinese invention patent CN202022924846.8 discloses a folding spud shoe structure, which is installed at the bottom of the leg of an ocean platform and includes a leg cylinder, a reinforcement structure and wing plates. The wing plates are arranged at equidistant intervals. On the outside of the pile leg cylinder, the reinforcement structure is fixed on the inside of the pile leg cylinder. The four openings of the mud-touching end of the pile leg cylinder are equipped with wing plates. The wing plates can be rotated and folded freely, and the wing plates can be rotated and opened. When parallel to the straight line between the pile leg pin hole and the through-axis hole, the area of the mud contact end can be increased to better bear the pressure load. Whether it is equipped with the above-mentioned retractable drilling platform spud shoe structure or a folding spud shoe structure, when the offshore platform is affected by wind, waves and ocean currents, the horizontal load generated will inevitably be transmitted to the spud shoes through the spud legs. However, due to design structural defects, the spud boots cannot be effectively inserted or the actual insertion depth is insufficient, and thus cannot meet the requirements of resisting horizontal impact loads. This will inevitably increase the risk of lateral movement of the offshore platform and lead to the collapse of the offshore platform. Work safety cannot be effectively guaranteed. Therefore, technicians are urgently needed to solve the above problems.

Contents of the invention

Therefore, in view of the above-mentioned existing problems and deficiencies, the research team of the present invention collected relevant information, and after multiple evaluations and considerations, as well as continuous discussions and design improvements by the research team members, finally led to this kind of device that can withstand lateral loads. The advent of gravity spud boots.

In order to solve the above technical problems, the present invention relates to a gravity-type spud shoe that can withstand lateral loads and is used in the pile legs of offshore platforms. It includes a mounting base and an anti-lateral movement part. The installation base is assembled on the lower free end of the offshore platform leg. The anti-sideways movement part is composed of N pieces of inserting posts that are directly supported by the installation base and can be inserted deep below the seabed bearing layer, and N ≥ 1. In addition, a gravity-type spud shoe capable of withstanding lateral loads also includes a pressure-reducing part. The pressure reducing part includes a top contact bottom plate and an auxiliary connection unit. The top contact bottom plate is arranged in parallel just below the installation base, and has N avoidance gaps for the plug posts to freely pass through. The auxiliary connection unit is composed of M groups of link mechanisms connected between the installation base and the top contact bottom plate and evenly distributed around the periphery of the anti-lateral movement part, and M ≥ 2. When the top contact bottom plate contacts the soft soil layer on the seabed, as the sinking process of the offshore platform legs continues to advance, the top contact bottom plate is pressed below the soft soil layer on the seafloor, and due to the reverse thrust of the loose seabed As a result, the distance d between it and the installation base gradually decreases. In this process, each insertion column passes through the corresponding avoidance gap until it penetrates deep into the seabed force-bearing layer, and the bending of each link mechanism The folding angle changes adaptively synchronously.

As a further improvement of the technical solution of the present invention, lower friction-increasing protrusions are evenly distributed on the bottom wall that contacts the bottom plate. The lower friction-increasing protrusion is formed by the bottom wall touching the bottom plate and extending downward.

As a further improvement of the technical solution of the present invention, the linkage mechanism consists of an upper connecting rod assembly, a lower connecting rod assembly, an upper pin shaft, an intermediate pin shaft and a lower pin shaft. The upper link assembly is hinged with the mounting base through an upper pin. The lower link assembly is hingedly connected to the bottom plate through the lower pin. The intermediate pin is used to realize the articulation of the upper connecting rod assembly and the lower connecting rod assembly. Moreover, in the initial stage when the bottom plate is in contact with the soft soil layer on the seabed, the angle θ formed by the upper connecting rod assembly and the lower connecting rod assembly is less than 180°. As the sinking process of the offshore platform leg continues to advance, , the upper connecting rod assembly is bent relative to the lower connecting rod assembly, and θ decreases accordingly.

As a further improvement of the technical solution of the present invention, the upper connecting rod assembly is composed of an upper connecting rod whose Q pieces are always parallel to each other and are traversed by the upper pin shaft and the intermediate pin shaft at the same time. The lower connecting rod assembly is always parallel to the Q piece and is supported by the middle pin and the lower pin at the same time. It is composed of a traversing lower connecting rod; Q≥1.

As a further improvement of the technical solution of the present invention, the pressure reducing part also includes side pressure reducing plates that can be partially or completely pressed into the seabed soft soil layer. The side pressure reducing plates are in contact with the outer side walls of each lower connecting rod and are welded and fixed. Assuming that the angle formed between the side pressure reducing plate and the top contact bottom plate is β, then as the insertion column continues to advance deep into the seabed soil layer, β will increase accordingly; and when the insertion column is inserted relative to the bearing layer Once in place, 150°≤β≤170°.

As a further improvement of the technical solution of the present invention, lateral friction-increasing protrusions are evenly distributed on the outer side walls of the wing pressure-reducing plates. The side friction-increasing protrusions are formed by extending outward from the outer walls of the side wing pressure-reducing plates.

As a further improvement of the technical solution of the present invention, the mounting base is composed of a mounting base plate, a fixed base, and a hinge base assembly. The installation base plate and the lower free ends of the offshore platform legs are welded and fixed. The fixing base is used to insert and fix the insertion posts, and is directly welded to the bottom wall of the installation base plate. The hinge base assembly is composed of a Q piece welded to the bottom wall of the mounting base plate and a hinge base that is hinged to the upper connecting rod in one-to-one correspondence.

As a further improvement of the technical solution of the present invention, a gravity-type spud shoe that can withstand lateral load also includes a locking part. The locking part includes a locking block assembly and a driving part. The locking block assembly is composed of N pieces of locking blocks assembled on the inserting post. The driving part is composed of N linear motion elements used to drive the locking block to freely extend/retract the insertion post in a one-to-one correspondence. During the process of sinking the legs of the offshore platform, when the inserting column is inserted into place relative to the seabed bearing layer, the locking block is located directly below the bottom plate and is driven by the driving force of the corresponding linear motion element. When the inserting column is extended, θ and β are locked; during the process of retracting the offshore platform legs, the linear motion element starts in reverse to drive the locking block to retract into the inserting column. Then, the inserting column gradually lifts under the action of the lifting force. The ground escapes from the corresponding avoidance gap. During this process, θ gradually increases to 180°, while β gradually decreases. The seabed soil surrounded by the flank pressure reducing plates and the top contact bottom plate passes through the adjacent lower connection The gap or/and avoidance gap formed by the rod assembly is extruded and discharged.

As a further improvement of the technical solution of the present invention, a receiving cavity is provided in the inserting column for installing linear motion components. The outer wall of the inserting column is extended inwardly with a lateral mounting groove for the locking block to freely perform the extending/retracting action, and is connected with the accommodation cavity.

As a further improvement of the technical solution of the present invention, the linear motion element is preferably a direct drive motor or a reduction motor.

By adopting the above technical solution, in the early stage of the sinking of the offshore platform's pile legs, the pile shoes are in a retracted state (that is, the distance between the top contact bottom plate and the installation base is maintained at the maximum value), and they are executed synchronously with the pile legs. The sinking action continues until the pile boots contact the soft soil layer on the seabed. Then, as the sinking process of the offshore platform pile legs continues to advance, the contact bottom plate is pressed below the soft soil layer on the seafloor, and due to the reaction of the loose seabed, The distance between it and the installation base gradually decreases due to the thrust force, which means that each link mechanism undergoes bending deformation. At the same time, the inserting column performs axial displacement movement relative to the top contact bottom plate until it passes through Avoid the gap and insert into the soft soil layer on the seabed. Then, the sinking process of the offshore platform leg continues to advance, the top plate touches the bottom plate and continues to move downward into the saturated sand layer. The linkage mechanism is brought into the soft soil layer on the seafloor. And the inserting column is inserted deeply into the bearing layer. During the extraction operation stage of the offshore platform pile legs, the inserting columns are gradually extracted from the bearing layer. At the same time, the top contact bottom plate and the connecting rod mechanism are respectively extracted from the seabed soft soil layer and saturated sand layer. Due to the pulling force, the linkage mechanism returns from the bent state to the initial folded state (the distance between the top contact bottom plate and the installation base gradually increases to the maximum value), and simultaneously, the top contact bottom plate is covered. The soil on the seabed is squeezed and expelled.

From the above description, it can be seen that gravity-type spud boots that can withstand lateral loads have at least achieved the following beneficial effects in practical applications:

1) When the offshore platform's pile legs complete the final sinking construction, the inserting columns are deeply inserted into the bearing layer, so that the pile boots have better lateral force resistance, thereby ensuring that the offshore platform can withstand horizontal impact loads. requirements, which means that the risk of side movement is reduced when it is affected by a series of horizontal loads such as wind, waves, ocean currents, etc., ultimately ensuring that the offshore platform has high working safety;

2) The top contact bottom plate has a relatively large top contact area, and when the offshore platform pile legs complete the final sinking construction, they can top contact with the hard bearing layer, thereby ensuring that the pile boots have better resistance. Axial load capacity;

3) Compared with the traditional design structure, the spud boots of the new design structure are easier to penetrate into the seabed. This is specifically reflected in the following: when the top contact bottom plate passes through the soft soil layer of the seabed, it enters the saturated sand layer, and completes the top with the bearing layer. During the contact process, the posture of the spud shoe changes adaptively (the bending of the link mechanism The bending angle can be adaptively changed according to the actual reverse thrust of the seafloor), so as to reduce the resistance of the spud boots as much as possible during the process of penetrating into the seabed soil layer; and when the top contact with the bottom plate is finally achieved, the top contact of the bearing layer is achieved , the spud shoe is deformed into a fully deployed state (the bending angle of the linkage mechanism is kept at a small value), which not only increases the axial load resistance capacity of the spud shoe to a certain extent, but also improves the anchorage of the spud shoe relative to the seabed. Determine reliability.

4) Compared with the traditional design structure, the spud boots of the new design structure are easier to pull out from the seabed soil layer (including seabed soft soil layer, saturated sand layer, and bearing layer). This is specifically reflected in: when the top touches the bottom plate and is In the process of separating from the bearing layer due to the action of the upward pulling force, and then entering the soft soil layer on the seabed through the saturated sand layer, the posture of the spud shoe gradually changes from the unfolded state to the retracted state (the bending of the linkage mechanism The angle can be adaptively increased according to the actual reverse thrust of the seafloor), and the contact area of the mud end of the spud shoe can be reduced so that it is subject to a smaller resistance force, ultimately ensuring that a small amount of water can be utilized in actual operations. The pile shoe can be smoothly extracted from the seabed soil layer with just a small amount of force to achieve the design goal.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

Figure 1 is a perspective view of a first embodiment of a gravity-type spud shoe according to the present invention, which can withstand lateral loads.

FIG. 2 is a front view of FIG. 1 .

Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2 .

Figure 4 is a schematic three-dimensional view from another perspective of the first embodiment of the gravity-type spud shoe in the present invention that can withstand lateral loads.

Figure 5 is a schematic diagram of the posture conversion of the gravity-type spud shoe that can withstand lateral loads according to the first embodiment of the present invention (converting from an expanded state to a compressed state).

Figure 6 is a schematic diagram of the application state of the gravity-type spud shoes that can withstand lateral loads according to the first embodiment of the present invention when they are matched with the offshore platform spud legs.

Figure 7 is a schematic perspective view of a second embodiment of a gravity spud shoe capable of withstanding lateral loads in the present invention.

Figure 8 is a schematic perspective view of a third embodiment of a gravity spud shoe capable of withstanding lateral loads in the present invention.

FIG. 9 is an enlarged view of part I of FIG. 8 .

1-Installation base; 11-Installation base plate; 12-Fixed seat; 13-Hinge seat assembly; 131-Hinge seat; 2-Anti-lateral movement part; 21-Insert column; 3-Decompression part; 31-Top bottom plate ; 311-avoidance gap; 32-auxiliary connection unit; 321-link mechanism; 3211-upper connecting rod assembly; 32111-upper connecting rod; 3212-lower connecting rod assembly; 32121-lower connecting rod; 3213- Upper pin; 3214-middle pin; 3215-lower pin; 33-side decompression plate; 4-locking part; 41-locking block assembly; 411-locking block.

Detailed ways

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "front", "back", "upper", "lower", "left", "right", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

According to common knowledge, the pile boots are used in conjunction with the pile legs of the offshore platform, which can effectively reduce the puncture force on the seabed bearing layer, thereby avoiding the occurrence of slow settlement of the offshore platform. As shown in Figure 6 It can be seen clearly.

The content disclosed in the present invention will be further described in detail below with reference to specific embodiments. Figures 1 and 4 respectively show two different views of the first embodiment of the gravity-type spud shoe that can withstand lateral loads in the present invention. From the three-dimensional schematic diagram, it can be seen that it is mainly composed of a mounting base 1, an anti-lateral movement part 2 and a pressure reducing part 3. Among them, the installation base 1 is welded to the sea The lower free end of the platform leg. The anti-lateral movement part 2 is composed of four inserts 21 which are directly borne by the installation base 1 and can be inserted deeply below the seabed bearing layer. The pressure reducing part 3 includes a top contact bottom plate 31 and an auxiliary connection unit 32 . The top contact bottom plate 31 is arranged in parallel just below the installation base 1, and has four avoidance gaps 311 for the inserting posts to freely pass through. The auxiliary connection unit 32 is composed of four sets of link mechanisms 321 connected between the mounting base 1 and the contact bottom plate 31 and evenly distributed around the periphery of the anti-lateral movement part 2 . When the bottom plate 31 is in contact with the soft soil layer on the seabed, as the sinking process of the offshore platform legs continues to advance, the bottom plate 31 is pressed below the soft soil layer on the seafloor, and due to the reverse thrust of the loose seabed As a result, the distance d between it and the installation base 1 gradually decreases. In this process, each inserting column 21 passes through the corresponding avoidance gap 311 until it penetrates deep into the seabed force-bearing layer, and each connecting rod The bending angle of the mechanism 321 changes adaptively synchronously (as shown in Figures 2 and 3).

At the early stage of the sinking of the offshore platform's pile legs, the pile shoes are in a retracted state (that is, the distance between the top contact bottom plate 31 and the installation base 1 is maintained at the maximum value), and they perform the sinking action synchronously with the pile legs until the pile The boots are in contact with the soft soil layer on the seabed. Then, as the sinking process of the offshore platform pile legs continues to advance, the contact bottom plate 31 is pressed below the soft soil layer on the seafloor, and due to the reverse thrust of the loose seabed, The distance between it and the installation base 1 gradually decreases, which means that each link mechanism 321 undergoes bending deformation. At the same time, the insertion post 21 performs axial displacement movement relative to the top contact bottom plate 31 until it passes through the avoidance. The notch 311 is inserted into the soft soil layer on the seabed. Then, the sinking process of the offshore platform leg continues to advance, and the top plate 31 continues to move downward and enters the saturated sand layer. The linkage mechanism 321 is brought into the soft soil layer on the seafloor. in, and the inserting post 21 is inserted deeply into the bearing layer. During the extraction operation stage of the offshore platform pile legs, the inserting column 21 is gradually withdrawn from the bearing layer. At the same time, the top contact bottom plate 31 and the linkage mechanism 321 are respectively removed from the seabed soft soil layer and the saturated sand layer. When the link mechanism 321 is pulled out, the linkage mechanism 321 returns from the bent state to the initial folded state due to the pulling force (the distance between the top contact bottom plate 31 and the mounting base 1 gradually increases to the maximum value), and simultaneously, the The seabed soil covering the bottom plate 31 is squeezed and discharged (as shown in FIG. 5 ).

It has been verified by actual experiments that when the offshore platform's pile legs complete the final sinking construction, the inserting columns 21 are deeply inserted into the bearing layer, so that the pile boots have better lateral force resistance, thereby ensuring that the offshore platform meets the resistance level The requirement of directional impact load means that the risk of sideways movement is reduced when it is affected by a series of horizontal loads such as wind, waves, ocean currents, etc., ultimately ensuring that the offshore platform has high working safety. In addition, it can be clearly seen from Figures 1-4 that the top contact bottom plate 31 has a relatively large top contact area, and when the final sinking construction of the offshore platform legs is completed, it can withstand the hard holding force The layers are in contact with each other, thereby ensuring that the spud shoe has better resistance to axial load force.

In addition, it should be noted here that during the construction process of the offshore platform into the sea, the pile boots of the new design structure are easier to penetrate deep into the seabed, which is specifically reflected in: when the top contact bottom plate 31 enters the saturated sand through the seabed soft soil layer, In the soil layer, and in the process of completing the top contact with the bearing layer, the attitude of the spud shoe changes adaptively (the bending angle of the linkage mechanism 321 can change adaptively according to the actual reverse thrust of the seabed), so as to Reduce the resistance of the spud shoes as much as possible in the process of penetrating into the seabed soil layer; and when the top contact with the bottom plate 31 finally achieves the top contact of the bearing layer, the spud shoes deform to a fully deployed state (the bending angle of the linkage mechanism 321 remains (less than a small value), it can not only increase the axial load resistance capacity of the spud shoe to a certain extent, but also improve the anchoring reliability of the spud shoe relative to the seabed.

During the retraction operation of the offshore platform's pile legs, the pile boots of the new design structure are easier to pull out from the seabed soil layer (including seabed soft soil layer, saturated sand layer, and bearing layer). This is specifically reflected in: The top contact bottom plate 31 is separated from the bearing layer by the upward pulling force, and then enters the seabed soft soil layer through the saturated sand layer. The posture of the spud shoe gradually changes from the unfolded state to the retracted state (continuous). The bending angle of the rod mechanism 321 can be adapted to increase according to the actual reverse thrust of the seabed), and the contact area of the mud end of the spud shoe can be reduced so that it is subject to a smaller resistance force, ultimately ensuring that the actual During operation, the spud shoe can be smoothly extracted from the seabed soil layer with less force to achieve the design goal.

As shown in Figures 1-4, it can be clearly understood that the link mechanism 321 is composed of an upper link group 3211, lower connecting rod assembly 3212, upper pin 3213, intermediate pin 3214 and lower pin 3215. The upper link assembly 3211 is hingedly connected with the mounting base 1 through the upper pin 3213 . The lower link assembly 3212 is hingedly connected to the bottom plate 31 through the lower pin 3215 . The intermediate pin 3214 is used to realize the hinge connection between the upper link assembly 3211 and the lower link assembly 3212. And when the bottom plate 31 is not in initial contact with the soft soil layer on the seabed, the angle θ formed by the upper connecting rod assembly 3211 and the lower connecting rod assembly 3212 is less than 180°, and as the offshore platform leg sinks, As it continues to advance, the upper link assembly 3211 bends relative to the lower link assembly 3212, and θ decreases accordingly. The upper connecting rod assembly 3211 is composed of three upper connecting rods that are always parallel to each other and are traversed by the upper pin 3213 and the intermediate pin 3214 at the same time. The lower link assembly 3212 is composed of three lower links 32121 that are always parallel to each other and are traversed by the middle pin 3214 and the lower pin 3213 at the same time. By adopting the above technical solution for setting, on the one hand, on the premise of ensuring the smooth transformation of the spud shoe expansion and closing movements, the linkage mechanism 321 has an extremely simple design structure, which is conducive to low-cost manufacturing and implementation; on the other hand, When the spud shoe performs the attitude change action, a relatively small friction force is generated between the upper link structure 32111 and the lower link 32121, thereby effectively avoiding the occurrence of "dead point" or "stuck" problems.

After the settlement operation of the marine pile legs is completed, in order to further improve the anchoring force between the pile boots and the seabed soil layer (including the seabed soft soil layer, saturated sand layer, and bearing layer), the top contact bottom plate 31 can also be The bottom wall is evenly distributed with lower friction-increasing protrusions (not shown in the figure). The lower friction-increasing protrusion is formed by the bottom wall that contacts the bottom plate 31 and continues to extend downward. The presence of the lower friction-increasing protrusions can effectively increase the friction force when the bottom plate 31 is in contact with the seabed soil layer, thereby further improving the lateral force resistance of the spud boots, thereby reducing the impact of wind and waves on the offshore platform. , ocean currents and other horizontal loads, ultimately ensuring that the offshore platform has good application safety.

Furthermore, as shown in FIG. 3 , it can be clearly understood that the mounting base 1 is composed of a mounting base plate 11 , a fixed base 12 , and a hinge base assembly 13 . The installation base plate 1 is straight with the lower free end of the offshore platform leg. The joints are welded and fixed. The fixing base 12 is used to insert and fix the insertion posts 21, and is directly welded to the bottom wall of the mounting base plate 11. The hinge base assembly 13 is composed of three pieces of hinge bases 131 that are welded to the bottom wall of the mounting base plate 1 and are hinged to the upper connecting rod 32111 in one-to-one correspondence. In this way, on the one hand, on the premise of ensuring reliable fixation of the inserting column 21 and reliable articulation of the upper connecting rod 32111, the installation base 1 has an extremely simple design structure, which is easy to manufacture and implement; on the other hand, on the pile legs During the actual posture change process, the installation base 1 has high guiding accuracy, which is conducive to ensuring that the fixed insert 21 can pass through the avoidance gap 311 smoothly.

Figure 7 shows a schematic three-dimensional view of the second embodiment of the gravity-type spud shoe that can withstand lateral loads in the present invention. It can be seen that the difference compared with the above-mentioned first embodiment is that: in addition to the top contact bottom plate 31 In addition to the auxiliary connection unit 32, the pressure reducing part 3 is additionally provided with a side pressure reducing plate 33. During the sinking operation of the offshore platform's pile legs, the side pressure reducing plates 33 may be partially or entirely pressed into the seabed soft soil layer to enhance the lateral force resistance of the pile boots. The side decompression plates 33 are in contact with the outer side walls of each lower link 32121 and are welded and fixed. Assuming that the angle formed between the flank pressure reducing plate 33 and the top contact bottom plate 31 is β, as the insertion column 21 penetrates into the seabed soil layer (including the seabed soft soil layer, saturated sand layer, and bearing layer), the process continues. As it advances, β increases accordingly; and when the insertion post 21 is deeply inserted into the force-bearing layer, β is easily controlled between 150-170°.

By adopting the above technical solution, when the spud shoe is transformed from the folded state to the unfolded state, the side pressure reducing plate 33 keeps moving synchronously with the corresponding lower link 32121, thereby effectively increasing the The contact area of the mud end of the spud shoe makes it subject to a larger resistance force, thereby ensuring that the spud shoe has good anchoring force after it is settled in place relative to the seabed, which means that the spile shoe's ability to resist axial load force is improved. , ensuring that the offshore platform has better application safety.

In order to achieve similar design purposes, with reference to the structural form of the top contact bottom plate 31 , side friction-increasing protrusions (not shown in the figure) may also be evenly distributed on the outer walls of the wing pressure reducing plates 33 . The side friction-increasing protrusions are formed by extending outward from the outer side walls of the side pressure-reducing plates 33 .

Figures 8 and 9 respectively show the gravity-type spud shoe in the present invention that can withstand lateral loads. From the schematic three-dimensional view of the third embodiment and its partial enlarged view, it can be seen that the difference compared with the above-mentioned second embodiment is that the gravity-type spud shoe that can withstand the lateral load is also provided with a locking part 4. The locking part 4 is mainly composed of several parts such as a locking block assembly 41 and a driving part. The locking block assembly 41 is composed of four locking blocks 411 assembled on each plug post 21 . The driving part is composed of four direct drive motors used to drive each locking block 411 to freely extend/retract the insertion post in a one-to-one correspondence. The inserting column 21 is provided with a receiving cavity for installing the above-mentioned direct drive motor. The outer side wall of the inserting column 21 extends inward with a lateral mounting groove for the locking block 411 to freely perform extending/retracting actions, and is connected with the above-mentioned accommodation cavity.

During the process of sinking the legs of the offshore platform, when the inserting column 21 is inserted into place relative to the seabed bearing layer, the locking block 411 is located directly below the bottom plate 31 and is corresponding to the driving force of the direct drive motor. When the inserting post 21 is extended under the action, θ and β are locked. At this time, the side pressure reducing plate 33 is kept in a fully deployed state, effectively increasing the contact area of the mud end, thereby realizing the stability of the spud shoe in the seabed. The fixation reliability prevents it from being pulled out of the seabed soil due to a relatively small force; during the process of retracting the offshore platform legs, the direct drive motor starts in reverse to drive the locking block 411 to retract to the insertion position. In the column 21, subsequently, the inserted column 21 gradually escapes from the corresponding avoidance gap 311 under the action of the lifting force. In this process, θ gradually increases to 180°, and β gradually decreases. Here During the process, the side pressure reducing plates 33 are converted from the unfolded state to the retracted state, which effectively reduces the contact area of the mud end, which is conducive to the implementation of the design goal of pulling the spud shoe out of the seabed soil layer with less force; in addition, , during the process of the side pressure reducing plates 33 being retracted, the seabed soil surrounded by the side pressure reducing plates 33 and the top contact bottom plate 31 is squeezed through the gaps or/and avoidance gaps formed by the adjacent lower link assemblies 3212 Pressure discharge is conducive to the timely filling of the seawater into the cavity formed by the pile shoe and the seabed soil during the process of being pulled out, thereby effectively avoiding the "instant vacuum" caused by the instantaneous vacuum directly below the pile shoe in the early stage of pulling out. The phenomenon of "adsorption" occurs.

In practical applications, the direct drive motor can directly drive the locking block 411 without a transmission device. It has strong power and extremely high driving accuracy and stability. More importantly, when losing Under the premise of a certain power output, the direct drive motor has a relatively small design volume, which is easy to install and fix in the accommodation cavity. It should be noted here that in addition to using the above-mentioned direct drive motor to drive the locking block 411 to perform displacement movement, linear motion components such as reduction motors can also be selected according to different power requirements in actual application scenarios.

The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

A gravity-type spud shoe that can withstand lateral loads is used in the pile legs of offshore platforms. It includes a mounting base and an anti-lateral movement part; the mounting base is assembled on the bottom of the pile legs of the ocean platform. end; the anti-lateral movement part is composed of N pieces of inserts that are directly borne by the installation base and can be inserted deep below the seabed bearing layer, and N ≥ 1, and is characterized in that it also includes a decompression part ; The decompression part includes a top contact bottom plate and an auxiliary connection unit; the top contact bottom plate is arranged in parallel directly below the installation base, and has N number of avoidances on it for the plug posts to freely pass through. Gap; the auxiliary connection unit is composed of M groups of link mechanisms connected between the installation base and the top contact bottom plate and evenly distributed around the periphery of the anti-lateral movement part, and M ≥ 2 ; When the top contact bottom plate contacts the soft soil layer on the seabed, as the sinking process of the offshore platform pile legs continues to advance, the bottom contact bottom plate is pressed below the soft soil layer on the seafloor, and due to the soft soil layer on the seafloor, The reverse thrust of the soil causes the distance d between it and the installation base to gradually decrease. In this process, each of the inserts passes through the corresponding avoidance gap until it penetrates deep into the seabed. The force-bearing layer is provided, and the bending angles of each link mechanism are adaptively changed synchronously.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 1, characterized in that, there are lower friction-increasing protrusions uniformly distributed on the bottom wall touching the bottom plate; The protrusion is formed by extending downward from the bottom wall that contacts the bottom plate.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 1, characterized in that the linkage mechanism consists of an upper link assembly, a lower link assembly, an upper pin, and an intermediate pin. and a lower pin; the upper connecting rod assembly realizes hinged connection with the mounting base through the upper pin; the lower connecting rod assembly realizes hinged connection with the mounting base through the lower pin The hinge of the top contact bottom plate; and the intermediate pin is used to realize the hinge of the upper link assembly and the lower link assembly; and when the top contact bottom plate is not initially pushed against the soft soil layer on the seabed In the contact stage, the angle θ formed by the upper connecting rod assembly and the lower connecting rod assembly is less than 180°, and as the sinking process of the offshore platform leg continues to advance, the upper connecting rod assembly is relatively When the lower connecting rod assembly is bent, θ decreases accordingly.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 3, characterized in that the upper connecting rod assembly is always parallel to the Q piece and is simultaneously moved by the The upper pin is composed of an upper connecting rod traversed by the intermediate pin; the lower connecting rod assembly is composed of Q parts that are always parallel to each other and are simultaneously connected by the intermediate pin and the lower connecting rod. It consists of a lower connecting rod traversed by the pin; Q≥1.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 4, characterized in that the pressure-reducing part further includes side-wing pressure-reducing plates that can be partially or completely pressed into the bottom of the seabed soft soil layer. ; The side decompression plates are in contact with the outer side walls of each of the lower connecting rods, and are welded and fixed; assuming that the angle formed between the side decompression plates and the top contact bottom plate is β, As the insertion column continues to penetrate into the seabed soil layer, β increases; and when the insertion column is inserted into the position relative to the bearing layer, 150°≤β≤170°.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 5, characterized in that lateral friction-increasing protrusions are evenly distributed on the outer walls of the side wing pressure-reducing plates; The friction protrusion is formed by continuing to extend outward from the outer wall of the side wing pressure reducing plate.
A gravity-type spud shoe capable of withstanding lateral loads according to any one of claims 3-6, characterized in that the installation base is composed of a mounting base plate, a fixed base, and a hinge base assembly; The base plate and the lower free ends of the offshore platform legs are welded and fixed; the fixed seat is used to insert and fix the inserting column, and is directly welded to the bottom wall of the installation base plate; the hinge seat The assembly is composed of a hinge base with a Q piece welded to the bottom wall of the mounting base plate and hinged with the upper connecting rod in one-to-one correspondence.
A gravity-type spud shoe capable of withstanding lateral loads according to any one of claims 5-6, characterized in that it further includes a locking part; the locking part includes a locking block assembly and a driving part; The locking block assembly is composed of N pieces of locking blocks assembled on the plug; the driving part is composed of N linear motion elements used to drive the locking block to freely extend/retract the plug in one-to-one correspondence. ; In the process of sinking the legs of the offshore platform, when the inserting column is inserted into place relative to the seabed force-bearing layer, the locking block is located directly below the top contact bottom plate, and it is in the corresponding position. The plug is extended under the driving force of the linear motion element, and θ and β are locked; during the process of retracting the offshore platform legs, the linear motion element is started in reverse to drive the locking block to retract to the desired position. Then, the insertion post gradually escapes from the corresponding avoidance gap under the action of the lifting force. In this process, θ gradually increases. As large as 180°, and β gradually decreases, the seabed soil surrounded by the side pressure reducing plate and the top contact bottom plate passes through the gap formed by the adjacent lower link assembly or/and the avoidance Notch and squeezed out.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 8, characterized in that a receiving cavity is provided in the inserting column for installing the linear motion element; and the The outer side wall of the inserting column extends inwardly and is formed with a lateral mounting groove for the locking block to freely perform extending/retracting actions and which is connected with the accommodation cavity.
A gravity-type spud shoe capable of withstanding lateral loads according to claim 9, characterized in that the linear motion element is a direct drive motor or a reduction motor.