A small GM value bottom-sitting structure auxiliary installation structure and control method

Abstract

The application relates to a small-GM-value bottom-sitting structure auxiliary installation structure and a control method, which comprises a bottom-sitting offshore platform, four columns of the bottom-sitting offshore platform are defined as a first column, a second column, a third column and a fourth column in anticlockwise order, an air bag is installed on the outer side of each column, the air bag is expanded in an oval shape under the action of compressed air, the expansion degree of the air bag is adjusted according to the air volume of the compressed air, a single air bag is installed between a lower floating body and an upper floating body, and the air bag is filled with the area between the upper floating body and the floating body along the column in the maximum expansion state; the application further comprises a compressed air source on a ship, the compressed air source on the ship is communicated with each air bag through pipelines, and a control valve is installed on each pipeline. The platform can be safely bottom-sit under the condition of small GM value, and the bottom-sitting process of the platform can be automatically controlled, the platform can be controlled and adjusted, and the bottom-sitting work of the platform can be completed.

Description

TECHNICAL FIELD

[0001] The application relates to a bottom-sitting platform installation structure field, in particular to a small GM value bottom-sitting structure auxiliary installation structure and a control method. BACKGROUND

[0002] The bottom-sitting platform is a column bottom-sitting platform, and the column can keep the platform stable during sinking and floating, and the platform can sink and float stably.

[0003] With the needs of current projects, the transportation conditions and installation conditions of the bottom-sitting platform are more and more strict. For some bottom-sitting platforms, considering the special restrictions of the transportation water area and the installation sea conditions, the initial stability height of some bottom-sitting platforms is small, and the platform stability requirement of the platform towing working condition in the ship classification society standard can be met during transportation. However, during installation, the waterline area is affected, especially when the column contacts water, the waterline area suddenly changes, the floating center suddenly changes, which is not conducive to the stability of the platform, and in severe cases, the platform may be unstable or even capsized during installation, which brings great safety hazards.

[0004] For the bottom-sitting platform with small GM value, the waterline area changes slightly during installation, which may cause the platform to be unstable. How to ensure that the bottom-sitting platform with small GM value can complete the bottom-sitting action under safe and controllable conditions is a focus problem that needs to be researched and solved in the current ocean engineering. SUMMARY

[0005] In view of the above-mentioned defects in the prior art, the application provides a small GM value bottom-sitting structure auxiliary installation structure and a control method, so that the platform can be safely bottom-sitting under the condition of small GM value, and the bottom-sitting work of the platform can be completed automatically and controllably according to the platform bottom-sitting process.

[0006] The technical scheme adopted by the application is as follows:

[0007] A small GM value bottom-sitting structure auxiliary installation structure comprises a bottom-sitting offshore platform, four columns of the bottom-sitting offshore platform are defined as a first column, a second column, a third column and a fourth column in anticlockwise order in sequence, an air bag is mounted on the outer side of each column, the air bag is inflated in an oval shape under the action of compressed air, the inflation degree of the air bag is adjusted according to the air volume of the compressed air, a single air bag is mounted between a lower floating body and an upper floating body, and the air bag is filled in the region between the upper floating body and the floating body in the maximum inflation state; the installation structure further comprises a shipboard compressed air source, the shipboard compressed air source is communicated with each air bag through pipelines, and a control valve is mounted on each pipeline.

[0008] Further technical schemes of the application are as follows:

[0009] The outer side of the first column is provided with a first air bag, the outer side of the second column is provided with a second air bag, the outer side of the third column is provided with a third air bag, and the outer side of the fourth column is provided with a fourth air bag. A compressed air source on the ship is connected to a main pipe, the main pipe is branched into four branch pipes, and the branch pipes are connected to the first air bag, the second air bag, the third air bag and the fourth air bag respectively. A first control valve is arranged on the pipeline connected to the first air bag, a second control valve is arranged on the pipeline connected to the second air bag, a third control valve is arranged on the pipeline connected to the third air bag, and a fourth control valve is arranged on the pipeline connected to the fourth air bag. Each control valve is connected to the air source and the air bag or connected to the air bag and the atmosphere.

[0010] Each control valve is an electric three-way valve.

[0011] When the first air bag, the second air bag, the third air bag and the fourth air bag are not filled with compressed air, the initial stability height of the offshore platform is H0. When each air bag is inflated alone, the relationship between the air bag and the initial stability height of the offshore platform can be expressed by a function.

[0012] After the first air bag is inflated, it gradually expands, and the waterline surface gradually changes with the amount of compressed air, forming a new center of buoyancy M1 and a new center of gravity G1 with the offshore platform, and forming an initial stability height H1. wherein, The functional relationship between the first air bag and the amount of air intake q1 is As the amount of air intake increases, the initial stability height H1 gradually increases, and the center of buoyancy of the platform tends to rise.

[0013] After the second air bag is inflated, it gradually expands, and the waterline surface gradually changes with the amount of compressed air, forming a new center of buoyancy M2 and a new center of gravity G2 with the offshore platform, and forming an initial stability height H2. wherein, The functional relationship between the second air bag and the amount of air intake q2 is As the amount of air intake increases, the initial stability height H2 gradually increases, and the center of buoyancy of the platform tends to rise.

[0014] After the third air bag is inflated, it gradually expands, and the waterline surface gradually changes with the amount of compressed air, forming a new center of buoyancy M3 and a new center of gravity G3 with the offshore platform, and forming an initial stability height H3. wherein, The functional relationship between the third air bag and the amount of air intake q3 is As the amount of air intake increases, the initial stability height H3 gradually increases, and the center of buoyancy of the platform tends to rise.

[0015] ​​​When the fourth air bag is inflated, it gradually expands, and the waterline surface gradually changes with the compressed air, forming a new position M4 of the buoyancy center and a position G4 of the center of gravity together with the bottom-sitting offshore platform, thereby forming an initial stability height wherein, The function relationship between the fourth air bag and the air intake amount q4 is With the continuous increase of the air intake amount, the initial stability height gradually increases, and the buoyancy center of the platform tends to rise.

[0016] When the air bags in different combinations are in different air intake amounts, the initial stability height of the entire air bag and the platform The function relationship between the first air bag, the second air bag, the third air bag, and the fourth air bag after being inflated is The control system controls the air intake amount of each air bag according to the requirement of the initial stability height, thereby obtaining the required initial stability height and ensuring the safe and effective sinking installation of the platform.

[0017] A control method of a small GM value bottom-sitting structure auxiliary installation structure, characterized in that:

[0018] When the bottom-sitting offshore platform is moved to a specified position and is ready to sink, the bottom-sitting offshore platform (501) is floating on the water surface, at this time, there is no compressed air in the first air bag, the second air bag, the third air bag, and the fourth air bag, and the initial stability height of the platform is the original

[0019] S1 initial sinking:

[0020] The bottom-sitting offshore platform is ready to sink from the floating state, there is no compressed air in the first air bag, the second air bag, the third air bag, and the fourth air bag, and the bottom-sitting offshore platform relies on the ballast system to inject water into the ballast water tank of the sinking body, and the bottom-sitting offshore platform begins to slowly sink, at this time, the initial stability height of the bottom-sitting offshore platform meets the stability requirement, and the bottom-sitting offshore platform safely sinks;

[0021] S2 inclined sinking:

[0022] After the bottom-sitting offshore platform starts to sink from the floating state, the ballast water system is stopped, the inclination direction of the platform is determined according to the platform stability calculation, and the ballast water system is controlled to adjust the posture of the platform to the inclined state; the platform sinks in the inclined state under the influence of the ballast water.

[0023] At this time, the platform sinking body is above the waterline, and as the platform sinks, the sinking body gradually immerses in the water;

[0024] There is no compressed air in the first air bag, the second air bag, the third air bag, and the fourth air bag.

[0025] S3 waterline surface mutation:

[0026] The platform sinks in an inclined posture, when the submerged body is submerged, the platform column is in contact with the water surface, the waterline surface of the platform changes suddenly, and the stability changes;

[0027] The control system determines the state of the waterline surface of the platform according to the draft of the platform, controls the opening of the third control valve and the fourth control valve at the same time, the compressed air on the ship enters the third air bag and the fourth air bag through the pipe system, the first control valve and the fourth control valve remain closed, there is no compressed air in the first air bag and the second air bag, and the third air bag provides high initial stability due to inflation The fourth air bag provides high initial stability due to inflation

[0028]

[0029] With the help of the high initial stability provided by the third air bag and the fourth air bag, the initial stability at this time is high The control system determines the stability of the platform according to the high initial stability, controls the opening of the third control valve and the fourth control valve, controls the amount of compressed air entering the third air bag and the fourth air bag, ensures that the high initial stability is within a reasonable range, meets the stability requirements of the platform, and the platform sinks stably;

[0030] S4 suspension state:

[0031] The platform overcomes the influence of the sudden change of the waterline surface with the help of the high initial stability provided by the first air bag, the second air bag, the third air bag and the fourth air bag, and stably sinks in an inclined posture;

[0032] When the bottom of the submerged body of the platform is 1000mm away from the seabed, the control system controls the ballast system to barge out ballast water outside the platform at a gentle speed on the premise that the posture of the platform remains unchanged, the amount of ballast water inside the platform decreases, the gravity of the platform decreases, and the sinking speed gradually decreases until the platform stops sinking, and the bottom of the submerged body is about 500mm away from the seabed and suspended in water;

[0033] S5 posture adjustment, complete bottom sitting:

[0034] At this time, the platform is suspended in water in an inclined posture, the bottom of the submerged body is about 500mm away from the seabed, and the ballast water system of the platform adjusts the amount of ballast water in the ballast tank to adjust the posture of the platform to float and suspend in water;

[0035] The control system controls each control valve to be closed, maintains the amount of compressed air in the first air bag, the second air bag, the third air bag and the fourth air bag, and maintains the high initial stability of the platform.

[0036] After the platform floats, the ballast water system uniformly injects ballast water into the ballast tank of the submerged body, the gravity of the platform increases, the platform continues to sink, and the platform safely sits on the bottom and completes the bottom sitting and stabilizing work;

[0037] The control system controls the four control valves to open, disconnects the connection with the compressed air source on the ship, releases the compressed air in the first air bag, the second air bag, the third air bag and the fourth air bag, and restores the original state of each air bag, so that the platform is stably seated on the bottom and the installation is completed.

[0038] In S3, when the first column and the second column of the platform lifting end begin to contact the water surface, the control system controls the first control valve to open, the compressed air on the ship enters the first air bag, the first air bag starts to inflate, and provides the platform with an initial stability height At the same time, the control system controls the second control valve to open, the compressed air on the ship enters the second air bag, the second air bag starts to inflate, and provides the platform with an initial stability height

[0039]

[0040] At this time, the first air bag, the second air bag, the third air bag and the fourth air bag are inflated under the control of the control system, and the platform is provided with an initial stability height by the first air bag, the second air bag, the third air bag and the fourth air bag;

[0041] At this time, the initial stability height The control system determines the stability of the platform according to the initial stability height, controls the opening degree of the four control valves, so as to control the amount of compressed air entering the first air bag, the second air bag, the third air bag and the fourth air bag, ensure that the initial stability height is within a reasonable range, meet the stability requirements of the platform, and the platform sinks stably.

[0042] The beneficial effects of the present application are as follows:

[0043] (1) The present application automatically evaluates the initial stability height during the overall installation process, and ensures the safety of the platform seated on the bottom.

[0044] (2) The present application improves the sinking stability of the platform by using air bags without changing the performance of the platform itself.

[0045] (3) The present application is fully controlled, real-time and dynamically adjusted, avoids manual intervention, and has good reliability.

[0046] (4) The present application is suitable for auxiliary installation of low GM value seated platform, and is used to solve the safe and reliable installation of seated platform. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 It is a distribution diagram of the column and air bag of the present application.

[0048] Figure 2 It is a distribution diagram of the whole of the present application.

[0049] Figure 3 It is a state diagram of the present application for preparing sinking of the seated structure.

[0050] Figure 4 The state diagram of the invention for the inclined sinking posture of the bottom-sitting structure.

[0051] Figure 5 The state diagram of the invention for the inclined sinking of the bottom-sitting structure, and the abrupt change of the waterline surface.

[0052] Figure 6 The state diagram of the invention for the airbag inflation of the bottom-sitting structure, and the increase of the waterline surface.

[0053] Figure 7 The state diagram of the invention for the suspension of the bottom-sitting structure.

[0054] Figure 8 The state diagram of the invention for the leveling of the bottom-sitting structure, and the completion of the bottom-sitting.

[0055] Wherein: 101, first column; 102, second column; 103, third column; 104, fourth column;

[0056] 201, first airbag; 202, second airbag; 203, third airbag; 204, fourth airbag;

[0057] 301, first control valve; 302, second control valve; 303, third control valve; 304, fourth control valve;

[0058] 401, on-board compressed air source;

[0059] 501, bottom-sitting offshore platform. DETAILED DESCRIPTION

[0060] The specific embodiment of the invention will be described below in conjunction with the accompanying drawings.

[0061] The specific structure and function of the auxiliary installation structure of the small GM value bottom-sitting structure are as follows:

[0062] The bottom-sitting offshore platform 501 is included, and according to the arrangement position, the four columns are defined as the first column 101, the second column 102, the third column 103, and the fourth column 104 in counterclockwise order.

[0063] The first airbag 201 is installed on the first column 101, and the first airbag 201 can be elliptically expanded under the action of compressed air. At the same time, the expansion degree can also be adjusted according to the air volume of the compressed air.

[0064] The installation position of the first airbag 201 is located between the lower floating body and the upper floating body, and when fully expanded, it can fill the area between the upper floating body and the lower floating body along the column.

[0065] The bottom of the No. 1 air bag 201 is connected to a compressed air pipe, which can lead the compressed air on the ship into the air bag, or lead the compressed air in the air bag out of the air bag.

[0066] The No. 2 air bag 201 is installed on the No. 2 column 102, which can be expanded in an elliptical shape under the action of compressed air. Meanwhile, the expansion degree can be adjusted according to the amount of compressed air.

[0067] The installation position of the No. 2 air bag 201 is between the lower floating body and the upper floating body, which can fill the area between the upper floating body and the lower floating body along the column when maximally expanded.

[0068] The bottom of the No. 2 air bag 201 is connected to a compressed air pipe, which can lead the compressed air on the ship into the air bag, or lead the compressed air in the air bag out of the air bag.

[0069] The No. 3 air bag 203 is installed on the No. 3 column 301, which can be expanded in an elliptical shape under the action of compressed air. Meanwhile, the expansion degree can be adjusted according to the amount of compressed air.

[0070] The installation position of the No. 3 air bag 203 is between the lower floating body and the upper floating body, which can fill the area between the upper floating body and the lower floating body along the column when maximally expanded.

[0071] The bottom of the No. 3 air bag 203 is connected to a compressed air pipe, which can lead the compressed air on the ship into the air bag, or lead the compressed air in the air bag out of the air bag.

[0072] The No. 4 air bag 204 is installed on the No. 4 column 104, which can be expanded in an elliptical shape under the action of compressed air. Meanwhile, the expansion degree can be adjusted according to the amount of compressed air.

[0073] The installation position of the No. 4 air bag 204 is between the lower floating body and the upper floating body, which can fill the area between the upper floating body and the lower floating body along the column when maximally expanded.

[0074] The bottom of the No. 4 air bag 204 is connected to a compressed air pipe, which can lead the compressed air on the ship into the air bag, or lead the compressed air in the air bag out of the air bag.

[0075] The compressed air on the platform (i.e., the compressed air source 401 on the ship) is connected to the No. 1 air bag 201, the No. 2 air bag 202, the No. 3 air bag 203, and the No. 4 air bag 204 through pipes.

[0076] A No. 1 control valve 301 is installed in the pipeline connecting the air source to the No. 1 air bag 201, which is an electric three-way valve that can receive control from the control unit to connect the air source to the No. 1 air bag 201, or connect the No. 1 air bag 201 to the outside atmosphere.

[0077] The second control valve 302 is installed in the pipeline connecting the air source and the second air bag 202. The valve is an electric three-way valve, which can be controlled by the control unit to connect the air source and the second air bag 202, or to connect the second air bag 202 and the atmosphere.

[0078] The third control valve 303 is installed in the pipeline connecting the air source and the third air bag 203. The valve is an electric three-way valve, which can be controlled by the control unit to connect the air source and the third air bag 203, or to connect the third air bag 203 and the atmosphere.

[0079] The fourth control valve 304 is installed in the pipeline connecting the air source and the fourth air bag 204. The valve is an electric three-way valve, which can be controlled by the control unit to connect the air source and the fourth air bag 204, or to connect the fourth air bag 204 and the atmosphere.

[0080] When the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 are not filled with compressed air, the initial stability height of the platform at this time is When each air bag is inflated alone, the relationship between the initial stability height formed by the air bag and the platform can be expressed by a function.

[0081] After the first air bag 201 is inflated, it gradually expands, and the waterplane surface after expansion gradually changes with the amount of compressed air filled, forming a new buoyancy center position M1 and a new gravity center position G1 with the platform to form an initial stability height G1M1. wherein, The functional relationship between the initial stability height G1M1 and the amount of air q1 filled into the first air bag is As the amount of air filled increases, the initial stability height G1M1 gradually increases, and the buoyancy center of the platform tends to rise.

[0082] After the second air bag 202 is inflated, it gradually expands, and the waterplane surface after expansion gradually changes with the amount of compressed air filled, forming a new buoyancy center position M2 and a new gravity center position G2 with the platform to form an initial stability height G2M2. wherein, The functional relationship between the initial stability height G2M2 and the amount of air q2 filled into the second air bag is As the amount of air filled increases, the initial stability height G2M2 gradually increases, and the buoyancy center of the platform tends to rise.

[0083] After the third air bag 203 is inflated, it gradually expands, and the waterplane surface after expansion gradually changes with the amount of compressed air filled, forming a new buoyancy center position M3 and a new gravity center position G3 with the platform to form an initial stability height G3M3. wherein, The functional relationship between the initial stability height G3M3 and the amount of air q3 filled into the third air bag is As the amount of air filled increases, the initial stability height G3M3 gradually increases, and the buoyancy center of the platform tends to rise. ​​

[0084] When the fourth air bag 204 is inflated, it gradually expands, and its expanded waterline surface gradually changes with the amount of compressed air, forming a new metacentric position M4 and a new center of gravity position G4 with the platform, thereby forming a new initial stability height Wherein, The functional relationship between the fourth air bag air intake q4 and the initial stability height is With the continuous increase of the air intake, the initial stability height gradually increases, and the platform metacenter tends to rise.

[0085] When the air bags in different combinations are in different air intake conditions, the initial stability height of the entire air bag and platform The functional relationship between the initial stability height and the air intake of the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 after inflation is The control system can control the air intake of each air bag according to the requirement of the initial stability height, so as to obtain the required initial stability height and ensure the safe and effective sinking of the platform.

[0086] The specific control method of the present application is as follows:

[0087] When the platform is moved to the specified position and is ready to sink, the platform is floating on the water surface, at this time, the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 are all without compressed air, and the initial stability height of the platform is the original

[0088] (I) Initial sinking:

[0089] The platform is ready to sink from the floating state, the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 are all without compressed air, and the platform sinks slowly by injecting water into the ballast water tank of the platform sinking body by the ballast system. At this time, the initial stability height of the platform meets the stability requirement, and the platform sinks safely.

[0090] (II) Inclined sinking:

[0091] After the platform starts to sink from the floating state, the ballast water system is stopped, and the inclination direction of the platform is determined according to the platform stability calculation. The ballast water system is controlled to adjust the attitude of the platform to the inclined state. The platform sinks in the inclined state under the influence of the ballast water. In order to facilitate the description, it is assumed that the platform is inclined to the third column 103 and the fourth column 104.

[0092] At this time, the platform sinking body is above the waterline, and as the platform sinks, the sinking body gradually immerses in the water.

[0093] The first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 are all without compressed air.

[0094] (III) Waterline surface mutation:​

[0095] The platform sinks in a tilted posture, when the submerged body is submerged in water, the platform column is in contact with the water surface, the platform waterline surface changes suddenly, and the stability changes.

[0096] The control system determines the platform waterline surface state according to the platform draft, and controls the third control valve 303 and the fourth control valve 304 to be opened at the same time, so that the compressed air on the ship enters the third air bag 203 and the fourth air bag 204 through the pipe system. The first control valve 301 and the fourth control valve 304 remain closed, and there is no compressed air in the first air bag 201 and the second air bag 202. The third air bag 203 provides a high initial stability due to inflation The fourth air bag 204 provides a high initial stability due to inflation

[0097] The platform sinks in a tilted posture, when the submerged body is submerged in water, the platform column is in contact with the water surface, the platform waterline surface changes suddenly, and the stability changes. The control system determines the platform waterline surface state according to the platform draft, and controls the third control valve 303 and the fourth control valve 304 to be opened at the same time, so that the compressed air on the ship enters the third air bag 203 and the fourth air bag 204 through the pipe system. The first control valve 301 and the fourth control valve 304 remain closed, and there is no compressed air in the first air bag 201 and the second air bag 202. The third air bag 203 provides a high initial stability due to inflation

[0098] When the first column 101 and the second column 102 of the platform at the raised end begin to contact the water surface, the control system controls the first control valve 301 to be opened, and the compressed air on the ship enters the first air bag 201, and the first air bag 201 begins to inflate and provides a high initial stability to the platform At the same time, the control system controls the second control valve 302 to be opened, and the compressed air on the ship enters the second air bag 202, and the second air bag 202 begins to inflate and provides a high initial stability to the platform

[0099] At this time, the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204 are all inflated under the control of the control system, and the platform relies on the high initial stability provided by the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204.

[0100] At this time, the initial stability is high The control system determines the platform stability according to the initial stability, controls the opening degree of the first control valve 301, the second control valve 302, the third control valve 303, and the fourth control valve 303, thereby controlling the amount of compressed air entering the first air bag 201, the second air bag 202, the third air bag 203, and the fourth air bag 204, ensuring that the initial stability is within a reasonable range, meeting the platform stability requirements, and the platform sinks stably.

[0101] (Four) Suspended state:

[0102] The platform overcomes the influence of the abrupt change of the waterline surface under the assistance of the high initial stability provided by the first air bag 201, the second air bag 202, the third air bag 203 and the fourth air bag 204, and is stably sunk in an inclined posture.

[0103] When the bottom of the platform submergence body is 1000mm away from the sea bottom, the control system controls the ballast system to discharge the ballast water outside the platform at a gentle speed under the premise that the posture of the platform is unchanged, the ballast water in the platform is reduced, the gravity of the platform is reduced, the sinking speed is gradually reduced, and the platform stops sinking until the bottom of the platform submergence body is about 500mm away from the sea bottom and is suspended in water.

[0104] (five) posture adjustment, completion of bottom sitting:

[0105] At this time, the platform is suspended in water in an inclined posture, and the bottom of the platform submergence body is about 500mm away from the sea bottom. The platform ballast water system adjusts the amount of ballast water in the ballast tank to adjust the posture of the platform to be flat and suspended in water.

[0106] The control system controls the first control valve 301, the second control valve 302, the third control valve 303 and the fourth control valve 303 to be closed, so as to maintain the amount of compressed air of the first air bag 201, the second air bag 202, the third air bag 203 and the fourth air bag 204, and maintain the high initial stability of the platform.

[0107] After the platform is flat, the ballast water system uniformly injects ballast water into the ballast tank of the platform submergence body, the gravity of the platform is increased, the platform continues to sink, until the platform is safely sat on the bottom, and the bottom sitting stabilization work is completed.

[0108] The control system controls the first control valve 301, the second control valve 302, the third control valve 303 and the fourth control valve 303 to be opened, disconnects the connection with the compressed air source 401 on the ship, releases the compressed air in the first air bag 201, the second air bag 202, the third air bag 203 and the fourth air bag 204, each air bag returns to the original state, the platform is stably sat on the bottom, and the installation is completed.

[0109] Table 1: experimental numerical list of each initial stability in each state

[0110]

[0111] By the control method of the present application, the safety problem caused by insufficient stability of the structure with small GM value during installation can be effectively solved. The initial stability of the structure is automatically evaluated at each stage under the premise that the control system is real-time perceived, and the safety of the platform sitting on the bottom is ensured. Meanwhile, the initial stability of the structure is not changed, which is convenient for installation and control, and can be used in the transportation and installation process of various marine structures with small GM value, so as to effectively eliminate the risk and improve the safety and reliability of engineering construction.

[0112] The above description is an explanation of the present application, not a limitation of the present application, the scope of the present application is defined in the claims, within the protection scope of the present application, any form of modification can be made.

Claims

1. A small GM value bottom founded structure assisted installation structure, comprising a bottom founded offshore platform (501), characterized in that: The four columns of the bottom-supported offshore platform (501) are defined in anticlockwise order as a first column (101), a second column (102), a third column (103) and a fourth column (104), and each column is externally provided with an air bag, which is inflated in an oval shape under the action of compressed air, and the inflation degree of the air bag is adjusted according to the air volume of the compressed air, and a single air bag is installed between the lower floating body and the upper floating body, and when the air bag is maximally inflated, the column is filled with the region between the upper floating body and the floating body; the bottom-supported offshore platform (501) further comprises a compressed air source (401) on the ship, the compressed air source (401) is communicated with each air bag through pipelines, and a control valve is installed on each pipeline; a first air bag (201) is installed on the outer side of the first column (101), a second air bag (202) is installed on the outer side of the second column (102), a third air bag (203) is installed on the outer side of the third column (103), and a fourth air bag (204) is installed on the outer side of the fourth column (104); When the first air bag (201), the second air bag (202), the third air bag (203) and the fourth air bag (204) are not filled with compressed air, the center of buoyancy position and the center of gravity position At this time, the initial stability height of the bottom-supported offshore platform (501) is When each air bag is inflated alone, the relationship between the air bag and the initial stability height formed by the bottom-supported offshore platform (501) can be expressed by a function; The first air bag (201) is inflated, gradually expands, and the waterline surface after expansion gradually changes with the compressed air, together with the bottom-supported offshore platform (501) to form a new position of the floating center and the position of the center of gravity to form the initial stability height , wherein and the function relationship between the air intake of the first air bag is With the continuous increase of the air intake, the initial stability height gradually increases, and the floating center of the platform tends to rise; The second air bag (202) gradually expands after being inflated, and the waterline surface after expansion gradually changes with the compressed air, together with the bottom-supported offshore platform (501) to form a new position of the floating center and the position of the center of gravity to form the initial stability height wherein, and the function relationship between the air intake of the second air bag is With the continuous increase of the air intake, the initial stability height gradually increases, and the floating center of the platform tends to rise; The third air bag (203) is gradually inflated after inflation, and the waterline surface after inflation gradually changes with the compressed air, together with the bottom-supported offshore platform (501) to form a new buoyancy center position and the center of gravity position to form the initial stability height , wherein and the function relationship between the third air bag air intake is With the continuous increase of the air intake, the initial stability height gradually increases, and the platform buoyancy center tends to rise; The fourth air bag (204) is gradually inflated after being inflated, and the waterline surface after inflation gradually changes with the compressed air, together with the bottom-supported offshore platform (501) to form a new position of the floating center and the position of the center of gravity to form the initial stability height , wherein and the function relationship between the air intake of the fourth air bag is With the continuous increase of the air intake, the initial stability height gradually increases, and the floating center of the platform tends to rise; When the air bags under different combinations are in different inflation gas amounts, the initial stability of the whole air bag and platform is high The functional relationship with the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204) after inflation is The control system controls the air inlet amount of each air bag according to the requirement of the initial stability, so as to obtain the required initial stability and ensure the safe and effective sinking installation of the platform.

2. A small GM value bottom founded structure auxiliary installation structure according to claim 1, characterized in that: Each control valve is an electric three-way valve.

3. A control method for the auxiliary installation structure of a small GM value bottom-supported structure according to claim 1, characterized in that: When the bottom-sitting offshore platform (501) is moved to the designated position and is ready to be floated, the bottom-sitting offshore platform (501) is floated on the water surface, at this time, the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204) are all without compressed air, and the initial stability of the platform is high ; S1 initial sinking: The bottom-supported offshore platform (501) is prepared to sink from the planing state, and there is no compressed air in the first air bag (201), the second air bag (202), the third air bag (203) and the fourth air bag (204), the bottom-supported offshore platform (501) relies on the ballast system to inject water into the lower floating body ballast tank, and the bottom-supported offshore platform (501) begins to slowly sink, at this time, the initial stability of the bottom-supported offshore platform (501) is high enough to meet the stability requirements, and the bottom-supported offshore platform (501) safely sinks; S2 inclined sinking: After the bottom-supported offshore platform (501) starts to sink from the planing state, the ballast water system is stopped, the inclination direction of the platform is determined according to the platform stability calculation, and the ballast water system is controlled to adjust the platform posture to an inclined state; the platform sinks in an inclined state under the influence of the ballast water; At this time, the platform lower floating body is above the waterline, and as the platform sinks, the lower floating body gradually immerses in the water; There is no compressed air in the first air bag (201), the second air bag (202), the third air bag (203) and the fourth air bag (204); S3 waterline surface mutation: When the lower floating body is immersed in water, the platform column is in contact with the water surface, the platform waterline surface is suddenly changed, and the stability is changed; The control system determines the waterline state of the platform according to the draft of the platform, controls the third control valve (303) and the fourth control valve (304) to be opened at the same time, the compressed air on the ship enters the third air bag (203) and the fourth air bag (204) through the pipeline, the first control valve (301) and the fourth control valve (304) remain closed, there is no compressed air in the first air bag (201) and the second air bag (202), the third air bag (203) provides high initial stability due to inflation , and the fourth air bag (204) provides high initial stability due to inflation . With the help of the high initial stability provided by the third air bag (203) and the fourth air bag (204), the high initial stability at this time , the control system determines the platform stability according to the high initial stability, controls the opening of the third control valve (303) and the fourth control valve (304), controls the amount of compressed air entering the third air bag (203) and the fourth air bag (204), ensures that the high initial stability is within a reasonable range, meets the platform stability requirements, and the platform sinks smoothly; S4 suspension state: The platform overcomes the influence of the waterline surface mutation under the assistance of the initial stability provided by the first air bag (201), the second air bag (202), the third air bag (203) and the fourth air bag (204), and stably sinks in an inclined posture; When the bottom of the platform lower floating body is 1000mm away from the seabed, the control system controls the ballast system to slowly discharge the ballast water outside the platform under the premise of keeping the platform posture unchanged, the internal ballast water of the platform decreases, the gravity of the platform decreases, and the sinking speed gradually decreases until the platform stops sinking, and the bottom of the lower floating body is about 500mm away from the seabed, and the lower floating body is suspended in the water; S5 posture adjustment, complete bottoming: At this time, the platform is suspended in water in an inclined posture, the bottom of the lower float is about 500 mm from the seabed, and the ballast water system of the platform adjusts the amount of ballast water in the ballast tank to adjust the posture of the platform to be flat and suspended in water. The control system controls the closing of each control valve to maintain the amount of compressed air in the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204), and to maintain the high initial stability of the platform. After the platform is flat, the ballast water system uniformly injects ballast water into the ballast tank of the lower float, the gravity of the platform increases, and the platform continues to sink until the platform is safely seated on the bottom and the seating and stabilization work is completed. The control system controls the opening of the four control valves, disconnects the connection with the compressed air source (401) on the ship, releases the compressed air in the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204), and each air bag returns to the original state, and the platform is stably seated on the bottom and the installation is completed.

4. The method of claim 3, wherein: S3, when the platform upturned end of the first column (101) and the second column (102) begin to contact the water surface, the control system control the first control valve (301) open, the ship compressed air into the first air bag (201), the first air bag (201) begins to inflate, and provide the platform with the initial stability height ; while the control system control the second control valve (302) open, the ship compressed air into the second air bag (202), the second air bag (202) begins to inflate, and provide the platform with the initial stability height ; At this time, the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204) are filled with compressed air under the control of the control system, and the platform uses the high initial stability provided by the first air bag (201), the second air bag (202), the third air bag (203), and the fourth air bag (204). The initial stability height at this time The control system determines the platform stability according to the initial stability height, controls the opening degree of the four control valves, and thus controls the compressed air amount entering the first air bag (201), the second air bag (202), the third air bag (203) and the fourth air bag (204), so as to ensure that the initial stability height is in a reasonable range, meet the platform stability requirement, and the platform sinks steadily.

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