A floating dock transfer analysis method
By verifying the finite element analysis and support reaction distribution diagram, and combining typical loading and stress condition analysis, the risk assessment problem in the process of launching large ships via floating dock was solved, achieving efficient and accurate safety assessment and ensuring the safety and controllability of the ship launching process.
Patent Information
- Application Number
- CN202510146190.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-10
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2045-02-10
AI Technical Summary
Existing technologies lack effective methods for risk assessment of the floating dock transshipment and launching process for large ships, resulting in low computational efficiency and low accuracy, and failing to ensure the safety and controllability of the ship launching process.
Finite element analysis was used to establish finite element models of the ship and the floating dock. The models were verified by the distribution diagrams of support reactions and ground pressure. Combined with typical loading and stress condition analysis, the loading scheme of the floating dock was determined to ensure that the stress on the ship in the floating dock meets the safety standards.
It improves the computational efficiency and simulation accuracy of the floating dock transfer process, ensures the safety and controllability of the ship launching process, and reduces the impact of external uncertainties on the launching process.
Smart Images
Figure CN119989814B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of ship manufacturing, in particular, to a floating dock transfer analysis method. BACKGROUND
[0002] With the continuous heating of global trade activities, the volume of goods transported between countries is showing a significant growth trend. In order to meet the needs of market competition and improve transportation efficiency and economy, large transport ships have emerged, and under the current global freight situation, the order volume of large transport ships is rising. At the same time, the dock resources of shipbuilding enterprises are usually limited and cannot be easily increased, so how to ensure that each batch of ships can be launched smoothly according to the established plan under the condition of limited dock resources through reasonable ways, thereby improving the overall production capacity, has become a key problem that needs to be solved in the shipbuilding industry. After the completion of large ships, they are usually launched by floating dock transfer. Compared with the inclined launching and the launching by slipway, the floating dock transfer launching method has higher stability. Specifically, during the launching process of the ship, the floating dock can provide good support for it, thereby reducing the shaking of the ship and helping to ensure the horizontal stability of the ship. In addition, when using the floating dock transfer launching method, the surrounding environment is under control, thereby reducing the influence of various external uncertain factors on the launching of the ship, and also providing a relatively safe operating environment for the workers.
[0003] When using inclined launching and launching by slipway, the traditional method usually analyzes the launching process by relying on engineering experience and simplified calculation method, while the floating dock transfer launching belongs to a quasi-static process and is not suitable for using the traditional method to analyze and evaluate it. Therefore, a feasible solution is to use finite element static analysis simulation to evaluate the structural strength and deformation analysis of the floating dock transfer launching process. However, although the finite element method has been applied to some extent in the field of ship structural strength evaluation, it has not been used to evaluate the risk of the floating dock transfer launching process of large ships, so there is a lack of relevant implementation methods. SUMMARY
[0004] The purpose of the embodiments of the present application is to provide a floating dock transfer analysis method that can effectively improve the calculation efficiency and simulation accuracy of the floating dock transfer process and better ensure the safety of the ship during the floating dock transfer.
[0005] The present application provides a floating dock transfer analysis method, comprising the following steps:
[0006] S1, in the finite element analysis software, the finite element model of the to-be-transferred ship and the bearing beam is established, wherein the bearing beam is fixedly arranged on the bearing trolley and can move with the bearing trolley, and the upper surface of the bearing beam is fixedly arranged with a plurality of pads for supporting the bottom of the to-be-transferred ship;
[0007] S2, according to the preset bearing trolley arrangement scheme, the plurality of bearing beams and the corresponding bearing trolleys are arranged below the to-be-transferred ship, then the jacking force is applied to all the bearing beams, the pads are driven by the bearing beams to support the bottom of the to-be-transferred ship, then the support reaction force of each pad is calculated according to the jacking force data of each bearing trolley on the corresponding bearing beam, and a support reaction force distribution map is formed;
[0008] S3, according to the support reaction force distribution map, the bearing beam is checked to determine whether there is a bearing beam with a deformation degree exceeding the allowable standard, if not, step S4 is entered, if yes, the preset bearing trolley arrangement scheme is modified, and then steps S2-S3 are repeated;
[0009] S4, the bearing trolley drives the to-be-transferred ship to move towards the interior of the floating dock, and a plurality of typical loading conditions are selected in the process from the to-be-transferred ship entering the floating dock to the to-be-transferred ship reaching the designated position in the floating dock, the floating dock is subjected to overall stress analysis according to the support reaction force distribution map under each typical loading condition, so as to determine the floating dock loading scheme under each typical loading condition. The floating dock contains a plurality of ballast tanks, and the loading refers to changing the overall load distribution of the floating dock by filling or draining water in different ballast tanks of the floating dock;
[0010] S5, in the finite element analysis software, the finite element model of the floating dock is established, and a plurality of typical stress conditions are selected in the process of the ship transferring from the outside of the floating dock to the designated position in the floating dock, and the stress distribution and deformation of the floating dock structure under the typical stress conditions are subjected to finite element analysis.
[0011] In an implementable scheme, in step S1, each two bearing trolleys are coded as a group, a bearing beam is fixedly arranged above each group of bearing trolleys, and the two ends of the bearing beam are fixedly arranged on the upper surfaces of the two bearing trolleys.
[0012] In an implementable scheme, all the pads have the same size and form complete contact with the outside of the ship.
[0013] In an implementable scheme, in step S2, the support reaction force of each pad is calculated by using the finite element analysis method, wherein the support reaction force of the pad is applied in the form of concentrated force on the surface of the bearing beam.
[0014] In an implementable solution, in step S2, the pressure of each bearing trolley on the ground is also calculated according to the jacking force data of each bearing trolley on the corresponding bearing girder, and a ground pressure distribution map is formed; in the ground pressure distribution map, the pressure of each bearing trolley is applied on the ground in the form of concentrated force.
[0015] In an implementable solution, step S3 includes the following specific steps:
[0016] S31, evaluate and sort the bearing reaction forces of each bearing girder through the bearing reaction force distribution map;
[0017] S32, select the bearing girder with the largest bearing reaction force from all the bearing girders as the bearing girder to be checked;
[0018] S33, perform strength checking on the bearing girder to be checked to determine whether the deformation degree of the bearing girder to be checked exceeds the allowable standard, if not, proceed to step S4; if so, modify the preset bearing trolley arrangement scheme, and then repeat steps S2-S3.
[0019] In an implementable solution, in step S4, while selecting the typical loading conditions, the seawater tide prediction data of the actual transfer period is also obtained, and then the seawater tide prediction data is combined with the bearing reaction force distribution map to perform overall stress analysis on the floating dock under the typical loading conditions.
[0020] In an implementable solution, in step S4, in combination with the ground pressure distribution map, during the process from the start of the to-be-transferred ship entering the floating dock to the arrival of the to-be-transferred ship at the designated position in the floating dock, whenever a first preset pressure value enters the floating dock, the current working condition is defined as a typical loading condition.
[0021] In an implementable solution, in step S4, the floating dock loading scheme should ensure that under each typical loading condition, the transverse inclination amplitude of the floating dock is less than 0.25% of the width of the floating dock, and the longitudinal inclination amplitude of the floating dock is less than 0.5% of the length of the floating dock.
[0022] In an implementable solution, in step S5, in combination with the ground pressure distribution map, during the process from the start of the to-be-transferred ship entering the floating dock to the arrival of the to-be-transferred ship at the designated position in the floating dock, whenever a second preset pressure value enters the floating dock, the current working condition is defined as a typical stress condition.
[0023] Compared with the prior art, the beneficial effects of the present application at least include:
[0024] The application provides a floating dock transfer analysis method, which respectively analyzes a ship supporting link, a floating dock loading link and a floating dock deformation link, can quickly and accurately simulate various stress conditions in the whole transfer process, and compares and analyzes various data with allowable standards, so as to judge whether the whole transfer process is safe and reliable. When the whole transfer process is analyzed by using a traditional method, a simplified calculation method is usually used, and the method is usually time-consuming and laborious, and many detail factors cannot be considered, thereby affecting the accuracy and accuracy of calculation. For example, when the floating dock is loaded by using the traditional method, the actual pressure of each ballast tank of the floating dock is manually calculated according to different draft depths listed in the floating dock loading manual, and the pressure is respectively applied to each ballast tank in the form of concentrated MPC+mass point, and if many dangerous working conditions occur in the process of calculating the pressure, the workload is greatly increased, so that the whole analysis process is uncontrollable. In comparison, the technical scheme of the application has great improvement in calculation efficiency, simulation accuracy and the like, and the whole transfer process is always controllable, and the calculation result can better ensure the safety of the ship when the ship is transferred by the floating dock. BRIEF DESCRIPTION OF DRAWINGS
[0025] In order to more clearly illustrate the technical scheme of the embodiments of the application, the drawings needed in the embodiments will be briefly introduced as follows, and it should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope, and other related drawings can also be obtained by those skilled in the art without creative labor on the premise of not paying creative labor.
[0026] Figure 1 It is a flow chart of the floating dock transfer analysis method shown in the embodiments of the application.
[0027] Figure 2 It is a support force distribution diagram.
[0028] Figure 3 It is a force diagram of a bearing beam.
[0029] Figure 4 It is a first ground pressure distribution diagram.
[0030] Figure 5 It is a second ground pressure distribution diagram.
[0031] Figure 6 It is a finite element analysis diagram of the floating dock ballast tank.
[0032] In the figure: 1, a ship to be transferred; 2, a floating dock; 3, a bearing beam; 4, a cushion block; L1, a first direction. DETAILED DESCRIPTION
[0033] To make the purposes, technical solutions, and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.
[0034] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.
[0035] As shown in Figure 1 The present application provides a floating dock transfer analysis method, characterized in that it comprises the following steps:
[0036] S1, in the finite element analysis software, a finite element model of the to-be-transferred ship and the bearing beam is established, wherein the bearing beam is fixedly arranged on the bearing trolley and can move with the bearing trolley, and a plurality of pads for supporting the bottom of the to-be-transferred ship are fixedly arranged on the upper surface of the bearing beam.
[0037] S2, according to the preset bearing trolley arrangement scheme, a plurality of bearing beams and corresponding bearing trolleys are arranged under the to-be-transferred ship, then a jacking force is applied to all bearing beams, the pads are driven by the bearing beams to form support for the bottom of the to-be-transferred ship, then the support reaction force of each pad is calculated according to the jacking force data applied to the corresponding bearing beam by each bearing trolley, and a support reaction force distribution map is formed, as shown in Figure 2 .
[0038] S3, according to the support reaction force distribution map, the bearing beam is checked to determine whether there is a bearing beam with a deformation degree exceeding the allowable standard, if not, step S4 is entered; if so, the preset bearing trolley arrangement scheme is modified, and then steps S2-S3 are repeated.
[0039] S4, the bearing trolley drives the to-be-transferred ship to move towards the inside of the floating dock, and a plurality of typical loading conditions are selected in the process from the to-be-transferred ship entering the floating dock to the to-be-transferred ship reaching the designated position in the floating dock, the floating dock is analyzed as a whole under each typical loading condition according to the support reaction force distribution map, so as to determine the floating dock loading scheme under each typical loading condition. The floating dock contains a plurality of ballast tanks, and the loading refers to changing the overall load distribution of the floating dock by filling or draining water in different ballast tanks of the floating dock.
[0040] S5, in the finite element analysis software, the finite element model of the floating dock is established, and a plurality of typical stress conditions are selected in the process of transferring the ship from outside the floating dock to the designated position in the floating dock, and the stress distribution and deformation of the floating dock structure under the typical stress conditions are analyzed by the finite element method.
[0041] The technical scheme of the present application analyzes the ship supporting link, the floating dock loading link and the floating dock deformation link, can quickly and accurately simulate various stress conditions in the whole transfer process, and compares and analyzes various data with the allowable standard, so as to judge whether the whole transfer process is safe and reliable. When the traditional method is used to analyze the whole transfer process, the simplified calculation method is usually used, which is usually time-consuming and laborious, and many detailed factors cannot be considered, thereby affecting the accuracy and accuracy of the calculation. For example, when the floating dock is loaded by using the traditional method, the actual pressure of each ballast tank of the floating dock is first calculated manually according to different draft depths listed in the floating dock loading manual, and then the pressure is applied to each ballast tank in the form of concentrated MPC+mass point. If there are many dangerous working conditions in the process of calculating the pressure, the workload will be greatly increased, and the whole analysis process is uncontrollable. In comparison, the technical scheme of the present application has great improvement in calculation efficiency, simulation accuracy and the like, and the whole transfer process is always controllable, and the calculation result can better ensure the safety of the ship during the floating dock transfer.
[0042] In an embodiment, in step S1, each two carrying trolleys can be coded as a group, and a bearing beam is fixedly arranged above each group of carrying trolleys, wherein the two ends of the bearing beam are fixedly arranged on the upper surfaces of the two carrying trolleys. Preferably, two or three evenly spaced pads can be arranged on each bearing beam, and the specific number and arrangement of the pads can be changed as needed, which is not limited here. In addition, the pads can be made of wood, composite materials or concrete materials, and the specific materials are not limited.
[0043] In an embodiment, in step S2, the reaction force of each pad can be calculated by using the finite element analysis method, wherein the reaction force of the pad is applied to the surface of the bearing beam in the form of concentrated force. Preferably, all the pads can be set to have the same size and are in complete contact with the outside of the ship. Specifically, the ship structure and the bearing beam can be set to have no plastic deformation in the initial state, and then the pads can be simulated by using Spring units, and the stiffness of the Spring units can be taken as the stiffness of the actual pad material. After the calculation is completed, the stress value of the Spring unit is read, which is the actual reaction force of the pad. Then, the actual reaction force of the pad can be applied to the bearing beam in the form of concentrated force, and the stress and deformation of the bearing beam are analyzed.
[0044] In an embodiment, step S3 can include the following specific steps:
[0045] S31, evaluate and sort the support reaction forces borne by each load-bearing beam through the support reaction force distribution map;
[0046] S32, select the load-bearing beam bearing the largest support reaction force from all load-bearing beams as the load-bearing beam to be checked;
[0047] S33, perform strength checking on the load-bearing beam to be checked to determine whether the deformation degree of the load-bearing beam to be checked exceeds the allowable standard. If not, proceed to step S4. If so, modify the preset load-carrying trolley arrangement scheme and then repeat steps S2-S3.
[0048] For example, as shown in Figure 2 , according to the support reaction force distribution map, the load-bearing beam bearing the largest support reaction force is selected from all load-bearing beams for strength checking. Then, the specific values of the three support reaction forces are applied on the load-bearing beam in the form of concentrated force, as shown in Figure 3 , after finite element calculation, the final pad support reaction force does not exceed the allowable standard, and the absolute deformation of the load-bearing beam is small, so it can be determined that the current load-carrying trolley arrangement scheme can meet the needs of the ship transfer process. If the pad support reaction force exceeds the allowable standard, the load-carrying trolley can be added at the position where the pad support reaction force exceeds the standard, as well as the load-bearing beam and the pad, and through multiple iterative calculations, the load-carrying trolley arrangement scheme that can make the pad support reaction force meet the allowable standard can be determined.
[0049] In addition, as shown in Figure 4 and Figure 5 , in step S2, the pressure of each load-carrying trolley on the ground can also be calculated according to the jacking force data of each load-carrying trolley on the corresponding load-bearing beam, and the ground pressure distribution map can be formed by sorting, wherein the pressure of each load-carrying trolley is applied on the ground in the form of concentrated force.
[0050] In an embodiment, in step S4, while selecting the typical loading condition, the seawater tide prediction data of the actual transfer period is also obtained, and then the seawater tide prediction data is combined with the support reaction force distribution map to perform overall stress analysis on the floating dock under the typical loading condition. This is because, in the actual transfer process, in addition to the parameters of the ship to be transferred and the floating dock itself, the seawater tide is also an important factor that cannot be ignored. Since the floating dock is completely floating in seawater, the seawater tide will interfere with the longitudinal and transverse balance of the floating dock, which may cause the longitudinal and transverse inclination of the floating dock to exceed the allowable standard.
[0051] Since the ship enters the floating dock slowly in the actual transshipment, the whole process takes a long time, for example, it may take 5-10 hours, it is difficult to dynamically analyze the process of the whole ship entering the floating dock, therefore, the technical scheme of the application selects some typical loading conditions for static analysis. In step S4, in combination with the ground pressure distribution map, during the process of the to-be-transshipped ship entering the floating dock from the beginning to reaching the designated position in the floating dock, each time the first preset pressure value enters the floating dock, the current working condition is defined as a typical loading condition. The first preset pressure value can be set to 5% of the total ground pressure of all the bearing trolleys, that is, 20 typical loading conditions are selected. In addition, for the sake of simplicity, each time a certain length of the ship (for example, 5% of the total length of the ship) enters the floating dock, the current working condition can be defined as a typical loading condition. The specific selection method of the typical loading condition can be determined as appropriate, which is not limited here.
[0052] When loading the floating dock, the principle of keeping the ship vertical center as close as possible to the center of gravity of the floating dock should be followed, so that the longitudinal and transverse inclination of the floating dock does not exceed the allowable standard during transshipment, and the floating dock does not appear in the vertical condition, ensuring that the floating dock will not be deformed due to uneven stress, thereby avoiding the floating dock from being deformed due to uneven stress.
[0053] In an embodiment, in step S4, the floating dock loading scheme under each typical loading condition can be obtained by adjusting the water injection amount or the water discharge amount of each ballast tank of the floating dock, so as to ensure that the transverse inclination of the floating dock is less than 0.25% of the width of the floating dock, and the longitudinal inclination of the floating dock is less than 0.5% of the length of the floating dock. In addition, according to the specific ship and floating dock size and the requirements of the launching area, the transverse inclination and longitudinal inclination of the floating dock can also be appropriately adjusted, for example, the transverse inclination and longitudinal inclination of the floating dock can be set to be less than 0.2% and 0.4%, respectively.
[0054] In an embodiment, in step S5, the finite element model of the floating dock can be established in the finite element analysis software by combining the design drawing of the floating dock with the plate and shell element simulation. In the process of creating the finite element model of the floating dock, the spatial distribution of the internal ballast tanks and the positions of the openings of each cabin should be confirmed in combination with the design drawing of the floating dock to ensure the accuracy of the internal cabin of the floating dock finite element model and ensure that the boundaries of each cabin are consistent with the actual structure, so as to apply the ballast water load for achieving the longitudinal and transverse balance of the floating dock in the subsequent steps. According to the actual empty ship weight distribution of the floating dock, the weight of the finite element model can be adjusted according to the rib position of the floating dock to ensure that the weight distribution of the finite element model is consistent with the actual weight distribution. Specifically, the deviation between the center of gravity of the finite element model and the actual center of gravity can be not more than 1% of the length of the floating dock. The means for adjusting the weight of the finite element model can include but are not limited to: directly assigning different density values to the material of the floating dock in the finite element software to adjust the weight distribution of the floating dock; and adjusting the weight difference between the model and the actual structure by adjusting the mass point, wherein the mass point refers to the concentrated mass load applied to certain nodes at each rib position in the floating dock model.
[0055] Similarly, since the ship enters the floating dock slowly during actual transshipment, it is difficult to dynamically analyze the entire process of the ship entering the floating dock, so the technical solution of the present application selects some typical stress conditions for static analysis. As shown in Figure 4 During the process of driving the to-be-transshipped ship 1 into the floating dock 2 along the first direction L1 by the carrying trolley, the bending moment curve profile of the floating dock will change accordingly, so when selecting typical stress conditions, the bending moment peak value should be as large as possible and the bending moment curve profile difference should be as obvious as possible. Specifically, in step S5, in combination with the ground pressure distribution diagram, during the process from the start of the to-be-transshipped ship entering the floating dock to the to-be-transshipped ship reaching the designated position in the floating dock, each time a second preset pressure value enters the floating dock, the current working condition is defined as a typical stress condition. The second preset pressure value can be set to 5% of the total ground pressure of all carrying trolleys, i.e., 20 typical stress conditions are selected. In addition, for the sake of simplicity, each time a certain ship length (for example, 5% of the total length of the ship) enters the floating dock, the current working condition can be defined as a typical stress condition. The specific selection method of the typical stress conditions can be determined as appropriate, which is not limited here.
[0056] When performing finite element analysis on each typical stress condition, first, load and boundary conditions are applied to the floating dock model, including but not limited to the pressure of the carrying trolley on the floating dock during ship transshipment, the gravity of the floating dock itself, the water gravity of the ballast tank of the floating dock, and the hydrostatic pressure of the outer shell and other internal cabin static pressure. Specifically, as shown in Figure 4 and Figure 5As shown, according to the ground pressure distribution map, the ground pressure distribution of all bearing trolleys on the floating dock at any time point during the transfer process can be easily obtained. By establishing a weight condition, the self-gravity of the floating dock can be automatically generated and applied to the floating dock finite element model. Under different typical stress conditions, due to the different draft depths of the floating dock, the static water pressure of the ballast water and other internal compartments in the floating dock and the shell static water pressure will change accordingly. In order to improve the calculation efficiency and ensure the calculation accuracy, the technical scheme of the present application does not use the traditional method of constraining MPC+mass point, but defines a corresponding local coordinate system for each ballast tank, and then quickly applies static water pressure to multiple ballast tanks by modifying the draft depth value of the floating dock, without the need for manual calculation of water pressure. Specifically, the water pressure formula P = pg h can be programmed into the finite element software, where p is the seawater density of the sea area where the transfer process is actually carried out, g is the acceleration of gravity, and h is the actual draft depth value of each ballast tank. In the finite element software, the static water pressure load is added by using the water pressure formula. For each ballast tank, the analysis coordinate of the static water pressure load is selected as the local coordinate of the corresponding ballast tank. For example, as shown in Figure 6 The actual draft height of a ballast tank of the floating dock is 4.2 m, so a local coordinate system with coordinate values (0, 0, 4200) is defined for the ballast tank, and the water pressure formula is used to apply the static water pressure load. Then, the local coordinate system is selected as the analysis coordinate, and the finite element software will automatically apply the static water pressure to all elements in the target ballast tank according to the height, without the need for manual calculation, which greatly improves the work efficiency. For the static pressure of other internal compartments of the floating dock, the static water pressure load can also be applied in the above-mentioned manner. It should be noted that since the floating dock has a certain longitudinal inclination during the transfer process, the bow and stern draft depths of the floating dock should be considered when applying the shell static water pressure load, so the local coordinate system should be defined for the bow and stern of the floating dock respectively.
[0057] After applying various loads to the floating dock in the above manner, the shear force and bending moment results can be obtained by integrating the loads, and the results can be compared with the actual shear force and bending moment listed in the floating dock loading manual. If the calculation results and the manual values can form a good fitting, it means that the calculation results are true and reliable. In the technical scheme of the present application, since the local coordinate system is defined, the error between the applied load in the finite element software and the actual load can be controlled within 1%, thereby improving the accuracy and efficiency of the calculation. Finally, the deformation and stress calculation results of the floating dock can be obtained, and the calculation results can be compared with the allowable standard listed in the floating dock loading manual to determine whether the entire transfer process can be safely and smoothly completed, thereby completing the evaluation of the floating dock transfer scheme.
[0058] The above descriptions are only the preferred embodiments of the present application, and are not intended to limit the present application. The present application can have various modifications and changes for those skilled in the art. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A floating drydock transshipment analysis method, characterized by, The method comprises the following steps: S1, in a finite element analysis software, a finite element model of a to-be-transshipped ship and a bearing beam is established, wherein the bearing beam is fixedly arranged on a bearing trolley and can move with the bearing trolley, and a plurality of pads for supporting the bottom of the to-be-transshipped ship are fixedly arranged on the upper surface of the bearing beam; S2, the plurality of bearing beams and the corresponding bearing trolleys are arranged under the to-be-transshipped ship according to a preset bearing trolley arrangement scheme, then a jacking force is applied to all the bearing beams, the pads are driven by the bearing beams to form support to the bottom of the to-be-transshipped ship, then the support reaction force of each pad is calculated according to the jacking force data applied to the corresponding bearing beam by each bearing trolley, and a support reaction force distribution map is formed; S3, the bearing beams are checked according to the support reaction force distribution map, whether there is a bearing beam with a deformation degree exceeding the allowable standard is judged, if not, step S4 is entered, if yes, the preset bearing trolley arrangement scheme is modified, and then steps S2-S3 are repeated; S4, the bearing trolley drives the to-be-transshipped ship to move towards the inside of the floating dock, and a plurality of typical loading conditions are selected in the process from the to-be-transshipped ship entering the floating dock to the to-be-transshipped ship reaching the designated position in the floating dock, the floating dock is subjected to overall stress analysis under each typical loading condition according to the support reaction force distribution map, so as to determine the floating dock loading scheme under each typical loading condition; the floating dock comprises a plurality of ballast tanks, and the loading refers to changing the overall load distribution of the floating dock by water injection or water discharge of different ballast tanks of the floating dock; S5, in the finite element analysis software, a finite element model of the floating dock is established, and a plurality of typical stress conditions are selected in the process of the ship transshipping from the outside of the floating dock to the designated position in the floating dock, and the stress distribution and deformation of the floating dock structure under the typical stress conditions are subjected to finite element analysis.
2. The analysis method of claim 1, wherein, In step S1, each two bearing trolleys are coded as a group, and a bearing beam is fixedly arranged above each group of bearing trolleys, and the two ends of the bearing beam are fixedly arranged on the upper surfaces of the two bearing trolleys.
3. The analysis method of claim 1, wherein, All the pads have the same size and form complete contact with the outside of the ship.
4. The analysis method of claim 1, wherein, In step S2, the support reaction force of each pad is calculated by using the finite element analysis method, wherein the support reaction force of the pad is applied to the surface of the bearing beam in the form of concentrated force.
5. The analysis method of claim 1, wherein, In step S2, the pressure of each bearing trolley on the ground is also calculated according to the jacking force data applied to the corresponding bearing beam by each bearing trolley, and a ground pressure distribution map is formed; In the ground pressure distribution map, the pressure of each bearing trolley is applied to the ground in the form of concentrated force.
6. The analysis method of claim 1, wherein, Step S3 comprises: S31, the support reaction force of each bearing beam is evaluated and sorted by the support reaction force distribution map; S32, the bearing beam with the largest support reaction force is selected from all the bearing beams as a to-be-checked bearing beam; S33, the strength of the to-be-checked bearing beam is checked, whether the deformation degree of the to-be-checked bearing beam exceeds the allowable standard is judged, if not, step S4 is entered, if yes, the preset bearing trolley arrangement scheme is modified, and then steps S2-S3 are repeated.
7. The analysis method of claim 1, wherein, In step S4, the sea tide prediction data of the actual transfer period is obtained while the typical loading conditions are selected, and then the sea tide prediction data is combined with the support reaction force distribution diagram to analyze the overall stress of the floating dock under the typical loading conditions.
8. The analysis method of claim 5, wherein, In step S4, in combination with the ground pressure distribution diagram, during the process from the start of the to-be-transferred ship entering the floating dock to the arrival of the to-be-transferred ship at the designated position in the floating dock, each time the first preset pressure value enters the floating dock, the current working condition is defined as a typical loading condition.
9. The analysis method of claim 1, wherein, In step S4, the floating dock loading scheme should ensure that the transverse inclination amplitude of the floating dock is less than 0.25% of the width of the floating dock and the longitudinal inclination amplitude of the floating dock is less than 0.5% of the length of the floating dock under each typical loading condition.
10. The analysis method of claim 1, wherein, In step S5, in combination with the ground pressure distribution diagram, during the process from the start of the to-be-transferred ship entering the floating dock to the arrival of the to-be-transferred ship at the designated position in the floating dock, each time the second preset pressure value enters the floating dock, the current working condition is defined as a typical stress condition.
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