A high-precision leveling method for underwater base bed

Abstract

The present invention belongs to the technical field of bed leveling construction and relates to a method for high-precision leveling of an underwater bed, comprising: lowering a leveling frame and supporting two sets of support assemblies at its bottom on a leveled bed and a bed to be leveled, respectively; adjusting the height of the support assemblies so that the four corners of the frame are at standard elevations; a leveling platform vehicle moves from one end of the leveling frame to the other end, checking the elevations of the four corners of the frame; if the elevations do not meet the standards, adjusting the heights of the support assemblies until the four corners of the frame are at standard elevations after the leveling platform vehicle moves; throwing stones onto the bed to be leveled, checking the elevations of the four corners of the frame and adjusting them as needed to meet the standards; the leveling platform vehicle drives a scraper to move to level the stone-throwing area, checking the elevations of the four corners of the frame and adjusting them as needed to meet the standards; repeating the stone-throwing and scraper leveling steps until the bed leveling operation is completed at the current ship position; lifting the leveling frame, moving the leveling boat to the next ship position, and repeating the above steps until the underwater bed leveling operation of a preset length is completed. The present invention can achieve high-precision leveling of an underwater bed.

Description

Technical Field

[0001] The present invention belongs to the technical field of base bed leveling construction, and in particular relates to a high-precision leveling operation method for an underwater base bed. Background Art

[0002] Currently, underwater bed leveling operations can be categorized into manual and mechanical leveling methods. Manual leveling involves divers working underwater, achieving a maximum leveling accuracy of ±3cm. Manual leveling is labor-intensive and inefficient, making it primarily suitable for shallow waters. Mechanical leveling utilizes specialized leveling vessels or equipment for operations such as bed riprap and bed leveling. It offers high efficiency and suitability for both shallow and deep waters, achieving a maximum leveling accuracy of ±4cm.

[0003] However, with the high-quality development of engineering project construction, the underwater base bed needs to be leveled more finely. Some projects require the base bed leveling accuracy to reach a high precision requirement of ±2cm, but the current underwater base bed leveling operations cannot meet this requirement; in view of this, there is an urgent need to develop a high-precision leveling operation method for the underwater base bed. Summary of the Invention

[0004] In view of the shortcomings in the related art, the present invention provides a high-precision leveling operation method for an underwater base bed, aiming to improve the leveling accuracy of the underwater base bed to meet the requirements of higher-precision leveling operations for the base bed.

[0005] The present invention provides a method for high-precision leveling of underwater foundation bed, which uses a bottom-seated leveling vessel to carry out supplementary riprap fine leveling operations on the compacted foundation bed to be leveled.

[0006] The bottom-seated leveling boat includes a U-shaped leveling frame, a leveling platform vehicle connected to the leveling frame, and a leveling platform vehicle including multiple silos and scrapers connected to the lower edges of all silos. A set of height-adjustable support components are installed at the bottom of the two side frames arranged opposite to each other on the leveling frame.

[0007] The underwater bed high-precision leveling operation method includes the following steps:

[0008] S1. After the bottom-seated leveling vessel arrives at the construction site, it lowers the leveling frame and places two sets of support components on the leveled base bed and the compacted base bed to be leveled, respectively. The height of each support component is adjusted to initially ensure that the elevations of the four corners of the leveling frame meet the preset elevation requirements.

[0009] S2. Start the leveling platform vehicle and move it from one end of the leveling frame to the other end; check whether the elevations of the four corners of the leveling frame meet the preset elevation requirements; if not, adjust the heights of the support components and execute step S2 again until the elevations of the four corners of the leveling frame meet the preset elevation requirements after the leveling platform vehicle moves;

[0010] S3. Throw the preset cubic amount of stone in the silo onto the compacted base bed to be leveled; check the elevation of the four corners of the leveling frame and adjust it as needed to meet the preset elevation requirements;

[0011] S4. Start the leveling platform vehicle to drive the scraper to move along the leveling frame for a preset leveling stroke to level the rock-dumped area to form a base bed leveling layer; check the elevations of the four corners of the leveling frame at this time and adjust them as needed to meet the preset elevation requirements;

[0012] S5. Repeat steps S3 to S4 until the bed leveling operation at the current ship position is completed;

[0013] S6. Lift the leveling frame to remove the support assembly from the bed, move the bottom-seated leveling vessel to the next position, and execute steps S1 to S5 again until the preset length of underwater bed leveling operation is completed.

[0014] In some embodiments, in step S3, the particle size of the stone is 5 cm to 8 cm; in step S4, the average thickness of the base bed leveling layer is 30 cm.

[0015] In some embodiments, the support assembly at the bottom of one side frame of the leveling frame includes a pad beam extending along the length direction of the side frame and a plurality of lifting cylinders embedded in the top surface of the pad beam, and the support assembly at the bottom of the other side frame includes a plurality of hydraulic legs, and the plurality of lifting cylinders and the plurality of hydraulic legs jointly provide liftable support for the leveling frame; in step S1, the pad beam is supported on a leveled base bed, and the plurality of hydraulic legs are supported on a compacted base bed to be leveled.

[0016] In some embodiments, wing spars are protrudingly provided on both sides of the lower width direction of the cushion beam, the bottom surface of the wing spars is coplanar with the bottom surface of the cushion beam, and the top surface of the wing spars is inclined upward toward the cushion beam.

[0017] In some embodiments, a plurality of first limit blocks and a plurality of second limit blocks that are flipped upward are respectively provided on both sides of the width direction of the top of the pad beam, and the bottom of the side frame corresponding to the pad beam is clamped between the first limit blocks and the second limit blocks; two groups of stop blocks that are relatively arranged are protruded in the length direction of the bottom of the side frame corresponding to the pad beam, and the two ends of the pad beam in the length direction are clamped between the two groups of stop blocks.

[0018] In some embodiments, the number of jacking cylinders is five, two jacking cylinders are arranged at each end of the mat beam in the length direction, and one jacking cylinder is arranged in the middle of the mat beam in the length direction; the number of hydraulic support legs is two, and the two hydraulic support legs are respectively located at the two ends of the mat beam in the length direction;

[0019] In steps S1 to S4, when adjusting the elevation of the four corners of the leveling frame, first adjust the working stroke of the four jacking cylinders at both ends of the pad beam and the working stroke of the two hydraulic legs so that the elevation of the four corners of the leveling frame reaches the preset elevation requirements; then adjust the working stroke of the jacking cylinder in the middle of the pad beam so that the working stroke of the jacking cylinder is greater than the working stroke of the jacking cylinders at both ends of the pad beam, but the difference in working stroke does not exceed the elastic deformation of the middle of the pad beam relative to the two ends of the pad beam.

[0020] In some embodiments, a plurality of pulling and closing oil cylinders are embedded in the top surface of the cushion beam, and the bottom and top of the pulling and closing oil cylinders are connected to the cushion beam and the leveling frame respectively; the top of the hydraulic support leg is connected to the leveling frame;

[0021] In step S1, when the cushion beam has not yet been supported on the leveled base bed, the lifting cylinder is retracted inside the cushion beam, and the pulling and closing cylinder is retracted to a preset minimum stroke so that the cushion beam is pressed against the leveling frame; after the cushion beam is supported on the leveled base bed, the pulling and closing cylinder is depressurized, and the lifting cylinder is extended to lift the leveling frame.

[0022] In some embodiments, a measuring tower is installed at each corner of the leveling frame, and a positioning device is installed on the top of each measuring tower. The positioning device is a GPS + prism integrated device. The underwater bed high-precision leveling operation method also includes a calibration step, which is performed in a dock and includes the following steps:

[0023] Lift the hull of the bottom-leveling boat, lower the leveling frame to the ground and level it;

[0024] A total station is set up on the ground, prisms are placed at the four corners of the top surface of the leveling frame, and multiple prisms are placed along the length direction of the scraper. The total station is used to calibrate the relative position relationship between the four positioning devices and the four corners of the leveling frame, and the relative elevation relationship between the four corners of the leveling frame and the scraper.

[0025] In some of the embodiments, in step S1, after the leveling frame is lowered, the positioning devices on the top of the measuring tower are exposed above the water surface; in steps S1 to S4, the elevation measurement data of the four positioning devices are used, and combined with the relative position relationship between the four calibrated positioning devices and the four corners of the leveling frame, the elevations of the four corners of the leveling frame are obtained; a total station is set up on the shore, and the four positioning devices are observed using the total station to verify the elevations of the four corners of the leveling frame.

[0026] In some embodiments, the top surfaces of two side frames of the leveling frame are provided with tracks extending along the length direction of the side frames. The leveling platform vehicle drives the scraper to move along the tracks. The tracks include a plurality of track segments arranged in sequence along a straight line. The track segments are mounted on the leveling frame by bolts. The underwater bedbed high-precision leveling operation method further includes a track debugging step, which is performed in a dock and includes the following steps:

[0027] Lift the hull of the bottom-leveling boat, lower the leveling frame to the ground and level it;

[0028] Start the leveling platform car and make it move along the track from one end of the leveling frame to the other end;

[0029] Use a pressure differential static level to measure the height difference of the track and determine whether the height difference of the track meets the preset height difference requirements; if not, install at least one layer of gasket between the corresponding track segment and the leveling frame based on the measurement results of the track height difference, start the entire platform vehicle to move again, measure and determine the track height difference again; if yes, weld the multiple layers of gaskets together, and perform intermittent welding between the bottom gasket and the leveling frame, and between the top gasket and the track to complete the track debugging.

[0030] In some of the embodiments, in the calibration step, the calibration of the relative position relationship between the four positioning devices and the four corners of the leveling frame, and the calibration of the relative elevation relationship between the four corners of the leveling frame and the scraper are carried out between 4:00 and 6:00 in the morning; in the track debugging step, the measurement of the track height difference is also carried out between 4:00 and 6:00 in the morning.

[0031] Based on the above technical solution, the high-precision leveling operation method for the underwater base bed in the embodiment of the present invention ensures that the leveling frame always has good elevation accuracy throughout the entire base bed leveling operation process by scraping the entire platform vehicle in the air after the leveling frame sits on the bottom to eliminate instantaneous settlement, and adjusting the leveling frame elevation after each stone throwing and each scraping. By setting the pad beam, the settlement of the leveled base bed pressed against the pad beam is significantly reduced and the settlement is made uniform, thereby improving the state stability of the leveling frame during the base bed leveling operation. Therefore, the underwater base bed leveling accuracy can be significantly improved to meet the requirements of higher-precision leveling operations for the base bed. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0033] Figure 1 This is a flow chart of the underwater bed high-precision leveling method of the present invention;

[0034] Figure 2This is a front view of the leveling frame before it is lowered in the present invention;

[0035] Figure 3 This is a top view of the leveling frame before it is lowered in the present invention;

[0036] Figure 4 This is the main view of the leveling frame after it is placed on the bottom in the present invention;

[0037] Figure 5 for Figure 4 AA cross-sectional view;

[0038] Figure 6 is a schematic diagram of a leveling frame equipped with a support assembly according to the present invention;

[0039] Figure 7 A bottom view of the leveling frame equipped with the support assembly according to the present invention;

[0040] Figure 8 It is an overall schematic diagram of the cushion beam in the present invention;

[0041] Figure 9 This is a cross-sectional view of the jacking cylinder of the cushion beam in the present invention;

[0042] Figure 10 This is a cross-sectional view of the tensioning and closing cylinder of the cushion beam in the present invention;

[0043] Figure 11 This is a schematic diagram of the track height difference measurement in the present invention.

[0044] In the figure: 10. Leveling frame; 11. Side frame; 12. Stop block; 13. Track; 14. Track segment; 15. Gasket; 20. Pad beam; 21. Wing beam; 22. First limit block; 23. Second limit block; 30. Lifting cylinder; 31. Cylinder sleeve; 32. Plunger; 40. Closing cylinder; 41. Cylinder barrel; 42. Piston rod; 43. Connecting seat; 50. Hydraulic support leg; 60. Leveling platform trolley; 61. Silo; 611. Material level meter; 62. Scraper; 63. Feed hopper; 64. Material delivery pipe; 70. Leveling boat; 80. Measuring tower; 90. Pressure differential static level; 91. Liquid storage tank. DETAILED DESCRIPTION

[0045] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0046] In the description of the present invention, it should be understood that the terms "center", "lateral", "longitudinal", "up", "down", "top", "bottom", "inside", "outside", "left", "right", "front", "back", "vertical", "horizontal", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention.

[0047] The terms "first," "second," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or to implicitly indicate the quantity of the technical features indicated. Thus, a feature specified as "first," "second," etc. may explicitly or implicitly include one or more of the features.

[0048] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0049] refer to Figures 1-11 As shown, the present invention provides a high-precision underwater bed leveling method, utilizing a bottom-mounted leveling vessel 70 to perform supplementary riprap and fine leveling operations on a compacted bed to be leveled. The bottom-mounted leveling vessel 70 comprises a hull and a leveling machine located within an open space in the middle of the hull. The leveling machine comprises a U-shaped leveling frame 10 and a leveling platform 60 connected to the leveling frame 10. The leveling platform 60 includes multiple silos 61 and scrapers 62 connected to the lower edges of all silos 61. A set of height-adjustable support assemblies are mounted on the bottoms of two opposing side frames 11 of the leveling frame 10.

[0050] Further explanation, the whole platform vehicle 60 includes a lower vehicle connected to the leveling frame 10 in a sliding manner, and an upper vehicle connected to the hull in a sliding manner; a plurality of silos 61 are installed on the lower vehicle; the upper vehicle is equipped with a plurality of feeding hoppers 63 corresponding to the plurality of silos 61, and a feeding pipe 64 is hinged between each feeding hopper 63 and its corresponding silo 61, that is, the two ends of the feeding pipe 64 are hinged to the lower end of the feeding hopper 63 and the upper end of the silo 61 respectively; it can be understood by those skilled in the art that before the leveling frame 10 is lowered, the leveling frame 10 is retracted. The material delivery pipe 64 is placed in the opening space of the hull, and the upper and lower trolleys are staggered in the horizontal direction. The feeding hopper 63 and the silo 61 are also staggered. After the leveling frame 10 is lowered, the leveling frame 10 is located under the hull. The lower trolley descends with the lowering of the leveling frame 10, and the material delivery pipe 64 is also turned from an inclined state to a vertical state. The upper and lower trolleys are in a vertically aligned state, and the feeding hopper 63 and the silo 61 are also in a vertically aligned state. Stones are added to the silo 61 through the feeding hopper 63 and the material delivery pipe 64. During the subsequent bed leveling operation, the whole platform trolley 60 moves along the leveling frame 10, that is, the lower trolley and the upper trolley move synchronously.

[0051] The underwater bed high-precision leveling operation method includes the following steps:

[0052] S1. After the bottom-seated leveling vessel 70 sails to the construction site, the leveling frame 10 is lowered and two sets of support assemblies are respectively supported on the leveled base bed and the compacted base bed to be leveled; the heights of the support assemblies are adjusted to initially make the elevations of the four corners of the leveling frame 10 meet the preset elevation requirements.

[0053] S2. Start the leveling platform trolley 60 and move it from one end of the leveling frame 10 to the other end, that is, the leveling platform trolley 60 scrapes the floor in vain; the leveling platform trolley 60 is heavy, about 100t, which can eliminate the instantaneous settlement of the support components at the bottom of the leveling frame 10; check whether the elevations of the four corners of the leveling frame 10 meet the preset elevation requirements at this time; if the elevations of the four corners of the leveling frame 10 do not meet the preset elevation requirements, adjust the heights of each support component and execute step S2 again until the elevations of the four corners of the leveling frame 10 meet the preset elevation requirements after the leveling platform trolley 60 moves.

[0054] S3. Throw a preset amount of stone in the silo 61 onto the compacted base bed to be leveled. After the stone throwing is completed, check the elevation of the four corners of the leveling frame 10 and adjust it as needed. That is, if the elevation of the four corners of the leveling frame 10 changes, adjust the height of each supporting assembly so that the elevation of the four corners of the leveling frame 10 meets the preset elevation requirements.

[0055] S4. Start the leveling platform trolley 60 to drive the scraper 62 along the leveling frame 10 for a preset leveling stroke. During this movement, the scraper 62 pushes the stones from higher areas to fill the lower areas, carefully scraping and gradually compacting the already-dumped areas, thereby forming a flat and dense subgrade layer on the compacted subgrade to be leveled. The elevations of the four corners of the leveling frame 10 are then checked and adjusted as necessary to meet the preset elevation requirements. Furthermore, the preset leveling stroke can be set to approximately 2 meters. The volume of stones dumped in step S3 should be sufficient for one leveling stroke.

[0056] S5. Repeat steps S3 to S4 until the bed leveling operation at the current ship position is completed; that is, after each stone dumping is completed, the elevations of the four corners of the leveling frame 10 are checked and adjusted as needed, and then the scraper 62 moves to perform leveling; after each bed leveling of a preset leveling stroke is completed, the elevations of the four corners of the leveling frame 10 are checked and adjusted as needed, and then stone dumping is performed again, and this process is followed until the bed leveling operation at the current ship position is completed.

[0057] S6. Lift the leveling frame 10 to remove the supporting assembly from the bed, move the bottom-seated leveling vessel 70 to the next position, and execute steps S1 to S5 again until the preset length of underwater bed leveling operation is completed.

[0058] It is understandable that the scraper 62 moves along the leveling frame 10, and the elevation accuracy of the leveling frame 10 determines the elevation accuracy of the scraper 62, and the elevation accuracy of the scraper 62 is directly related to the leveling accuracy of the base bed; therefore, to achieve high-precision leveling of the underwater base bed, the leveling frame 10 must have good elevation accuracy. Further explanation: in step S2, after the leveling frame 10 is seated, the leveling platform vehicle 60 performs dry scraping, which has eliminated the instantaneous settlement of the support components at the bottom of the leveling frame 10. However, in the subsequent base bed leveling operation, due to the relatively long overall construction time, the support components will still slowly settle due to the effects of stone throwing, scraping, and time effects. Therefore, after each stone throwing and each scraping, the gap between process switching is used to check the elevation of the four corners of the leveling frame 10 and adjust it as needed to better overcome the influence of settlement and further ensure that the leveling frame 10 always has good elevation accuracy throughout the entire base bed leveling operation.

[0059] The above-mentioned schematic embodiment ensures that the leveling frame 10 always has good elevation accuracy during the entire base bed leveling operation, thereby effectively improving the underwater base bed leveling accuracy, by performing an empty scraping operation on the leveling platform vehicle 60 after the leveling frame 10 is seated to eliminate instantaneous settlement, and performing a leveling adjustment on the leveling frame 10 after each stone throwing and each scraping.

[0060] refer to Figure 5As shown, in some embodiments, in step S3, the particle size of the stone is 5cm to 8cm; in step S4, the average thickness of the base bed leveling layer is 30cm. It should be noted that under the traditional base bed leveling process, two pieces of stone are usually used for base bed leveling operations. The particle size of the two pieces of stone is 8cm to 15cm, and the thickness of the base bed leveling layer is about 50cm. Its thickness is relatively thick, so the settlement is large and difficult to control, which is not conducive to improving the base bed leveling accuracy. In this embodiment, the base bed is compacted using a vibration compaction process, the base bed settlement rate is not less than 15%, and the stone particle size is reduced and the thickness of the base bed leveling layer is reduced. This makes it easier to control the base bed settlement and reduce the base bed settlement, which is beneficial to improving the base bed leveling accuracy.

[0061] refer to Figure 5 As shown, in some embodiments, a material level gauge 611 is provided at the top and bottom of each silo 61 of the platform vehicle 60. The multiple material level gauges 611 of each silo 61 are arranged in a substantially regular triangle. When the top material level gauge 611 emits a signal, it indicates that the silo 61 is full and no further material is needed, thereby preventing excessive stone from scattering from the top of the silo 61 and affecting the leveling accuracy. When the bottom material level gauge 611 emits a signal, it indicates that the stone in the silo 61 can meet the requirements for riprap under the minimum leveling stroke, thereby preventing insufficient stone from causing insufficient material in the silo 61 and resulting in an incomplete subgrade. This allows for precise material control during the subgrade leveling operation.

[0062] refer to Figure 5 、 Figure 6 、 Figure 8 As shown, in some embodiments, the support assembly at the bottom of one side frame 11 of the leveling frame 10 includes a cushion beam 20 extending along the length of the side frame 11 and multiple lifting cylinders 30 embedded in the top surface of the cushion beam 20. The multiple lifting cylinders 30 are spaced apart along the length of the cushion beam 20. Specifically, the lifting cylinder 30 includes a coaxially arranged cylinder sleeve 31 and a plunger 32. The bottom end of the cylinder sleeve 31 is connected to the cushion beam 20, and the top end is inserted with the plunger 32. The plunger 32 includes a mutually connected plunger head and a plunger rod. The plunger head is slidably connected to the cylinder sleeve 31 and is dynamically sealed with the inner wall of the cylinder sleeve 31. The plunger rod seal passes through the cylinder sleeve 31. The plunger 32 can reciprocate axially along the cylinder sleeve 31, thereby making the height of the support assembly adjustable. The support assembly at the bottom of the other side frame 11 of the leveling frame 10 includes multiple hydraulic legs 50, which can be extended and retracted. Therefore, the plurality of jacking cylinders 30 and the plurality of hydraulic legs 50 jointly support the leveling frame 10 in a liftable manner.

[0063] In step S1, the cushion beam 20 is supported on the leveled bed, and the multiple hydraulic legs 50 are supported on the compacted bed to be leveled, thereby achieving the bottoming of the leveling frame 10. The measurement and control system on the bottom-settling leveling vessel 70 is in communication with the jacking cylinders 30 and the hydraulic legs 50. By remotely adjusting the working stroke of each jacking cylinder 30 and the hydraulic legs 50, the leveling frame 10 is leveled and the elevation of the four corners of the leveling frame 10 meets the preset elevation requirements.

[0064] The above-mentioned schematic embodiment, through the provision of the cushion beam 20, compared with the multi-leg multi-point support method commonly used in the current leveling frame 10, this embodiment significantly increases the contact area between the support assembly and the leveled base bed, greatly reduces the load of the support assembly on the leveled base bed, and thus significantly reduces the settlement of the support assembly and the leveled base bed it is pressed against and makes its settlement uniform, ensuring that the top surface elevation and leveling accuracy of the leveled base bed are not affected by the subsequent leveling operation of the base bed and can still meet the project quality requirements; through the provision of the jacking cylinder 30 and the hydraulic support legs 50, it is convenient to adjust the elevation of the leveling frame 10.

[0065] refer to Figures 8-10 As shown, in some embodiments, wing beams 21 are protruding on both sides of the lower width direction of the pad beam 20, the bottom surface of the wing beam 21 is coplanar with the bottom surface of the pad beam 20, and the top surface of the wing beam 21 is inclined upward toward the pad beam 20; thus, through the provision of the wing beam 21, the overall structural strength of the pad beam 20 is enhanced, and the contact area between the pad beam 20 and the leveled base bed is increased, thereby further reducing the settlement of the pad beam 20, that is, reducing the settlement of the leveled base bed in contact with the pad beam 20, better ensuring that the top surface elevation and leveling accuracy of the leveled base bed meet the engineering quality requirements, and also minimizing the subsequent settlement of the pad beam 20 during the base bed leveling operation, further improving the state stability of the leveling frame 10 during the base bed leveling operation, and thereby improving the base bed leveling accuracy.

[0066] In some embodiments, to further reduce the settlement of the cushion beam 20, the bases of the active and passive sprockets that drive the entire platform vehicle 60 are changed from conventional steel bases to engineering plastic bases, the sprocket brackets are changed from conventional steel brackets to engineering plastic brackets, and the sprocket axle sleeves are changed from conventional steel sleeves to polymer Hualong sleeves. This material modification reduces the vibration of the sprocket and anchor chain during operation, thereby reducing the settlement of the cushion beam 20 caused by vibration, which is conducive to improving the leveling accuracy of the base bed. Furthermore, the anchor chain installation state is adjusted, and chain supports are added according to the position of the taut anchor chain. Because the anchor chain has a certain curvature when taut, one side is lower and the other side is higher, the chain supports follow the height of the anchor chain, reducing the vibration of the rigid structure and thus reducing the impact on the settlement of the cushion beam 20. In addition, to reduce the vibration and jamming caused by the long anchor chain, marks are placed on the anchor chain at regular intervals to ensure the installation accuracy of the sprocket and anchor chain, reduce the vibration and jamming of the anchor chain during operation, avoid affecting the running accuracy, and also reduce the impact on the settlement of the cushion beam 20.

[0067] refer to Figure 7-10 As shown, in some embodiments, a plurality of first limit blocks 22 and a plurality of second limit blocks 23 that are flipped upward are respectively provided on both sides of the top width direction of the pad beam 20, and the bottom of the side frame 11 corresponding to the pad beam 20 is clamped between the first limit blocks 22 and the second limit blocks 23; two groups of relatively arranged stop blocks 12 are protruded in the length direction of the bottom of the side frame 11 corresponding to the pad beam 20, and the two ends of the pad beam 20 in the length direction are clamped between the two groups of stop blocks 12. This illustrative embodiment achieves matching limitation between the pad beam 20 and the leveling frame 10 by setting the first limit block 22, the second limit block 23 and the stop block 12, thereby avoiding relative movement between the two; in addition, during the base bed leveling operation, if the leveling frame 10 deflects due to reasons such as large local resistance of the scraper 62, the first limit block 22 and the second limit block 23 on the pad beam 20 can stop the leveling frame 10 from rotating, thereby avoiding the situation where the leveling frame 10 may deflect and affect the quality of the base bed leveling operation, ensuring the state stability of the leveling frame 10 during the base bed leveling operation, and helping to improve the base bed leveling quality.

[0068] refer to Figure 4-Figure 6 、 Figure 8 As shown, in some embodiments, the number of the jacking cylinders 30 is five, two jacking cylinders 30 are arranged at each end of the length direction of the pad beam 20, and one jacking cylinder 30 is arranged in the middle of the length direction of the pad beam 20; the number of the hydraulic support legs 50 is two, and the two hydraulic support legs 50 are respectively located at the two ends of the length direction of the pad beam 20.

[0069] In steps S1 to S4, when adjusting the elevation of the four corners of the leveling frame 10, first adjust the working stroke of the four lifting cylinders 30 at both ends of the pad beam 20 and the working stroke of the two hydraulic legs 50 so that the elevation of the four corners of the leveling frame 10 reaches the preset elevation requirements; then adjust the working stroke of the lifting cylinder 30 in the middle of the pad beam 20 so that the working stroke of the lifting cylinder 30 is greater than the working stroke of the lifting cylinders 30 at both ends of the pad beam 20, but the difference in working stroke does not exceed the elastic deformation of the middle of the pad beam 20 relative to the two ends of the pad beam 20. The elastic deformation can be obtained through theoretical calculation or experimental measurement, thereby avoiding the problem of insufficient lifting force of the middle lifting cylinder 30 due to the elastic deformation of the pad beam 20, ensuring the overall force-bearing area of ​​the pad beam 20, and thereby reducing the deformation of the leveling frame 10 and improving the elevation accuracy of the leveling frame 10.

[0070] refer to Figure 8 、 Figure 10 As shown, in some embodiments, a plurality of pulling and closing cylinders 40 are embedded in the top surface of the cushion beam 20. The bottom of the pulling and closing cylinders 40 is connected to the cushion beam 20, and the top of the pulling and closing cylinders 40 is connected to the leveling frame 10. However, the top of the lifting cylinder 30 is not fixedly connected to the leveling frame 10. Specifically, there are two pulling and closing cylinders 40, which are located on both sides of the lifting cylinder 30 in the middle of the cushion beam 20. Thus, the connection between the cushion beam 20 and the leveling frame 10 is achieved through the provision of the pulling and closing cylinders 40. The top of the hydraulic support leg 50 is connected to the leveling frame 10.

[0071] Furthermore, the pulling and closing cylinder 40 includes a coaxially arranged cylinder barrel 41 and a piston rod 42; one end of the cylinder barrel 41 is hinged to the pad beam 20 through a connecting seat 43, and the other end is inserted with a piston rod 42; the piston rod 42 includes a piston head and a connecting rod that are connected to each other, the piston rod 42 is slidably connected to the cylinder barrel 41 and is dynamically sealed with the inner wall of the cylinder barrel 41, the connecting rod seal passes through the cylinder barrel 41 and is hinged to the leveling frame 10 through a connecting seat 43, and the piston rod 42 can move back and forth along the axial direction of the cylinder barrel 41.

[0072] In step S1, when the leveling frame 10 is moving with the bottom-supported leveling vessel 70 or when the cushion beam 20 has not yet been supported on the leveled bed, the lifting cylinder 30 is retracted within the cushion beam 20, that is, the top surface of the lifting cylinder 30 does not contact the leveling frame 10, and the closing cylinder 40 is retracted to a preset minimum stroke so that the cushion beam 20 is pressed against the leveling frame 10; thereby ensuring that there is no relative movement between the cushion beam 20 and the leveling frame 10 when the leveling frame 10 is displaced, thereby ensuring the towing safety of the cushion beam 20. After the cushion beam 20 is supported on the leveled bed, the closing cylinder 40 is depressurized, and the lifting cylinder 30 is extended to lift the leveling frame 10; and when the lifting cylinder 30 is extended, the closing cylinder 40 will also extend; to ensure the safe and reliable performance of the closing cylinder 40, it is necessary to ensure that when the lifting cylinder 30 is extended to the preset maximum lifting stroke, the closing cylinder 40 is not extended to the preset maximum stroke. The measurement and control system on the bottom-supported leveling vessel 70 is also connected to the pulling and closing oil cylinder 40 for remotely controlling the contraction or pressure relief of the pulling and closing oil cylinder 40 .

[0073] Furthermore, a plurality of pads (not shown) are protruding from the top surface of the cushion beam 20. When the tensioning and closing cylinder 40 is retracted to a preset minimum stroke, the pads come into contact with the bottom surface of the leveling frame 10, thereby pulling the cushion beam 20 and the leveling frame 10 together. It should be noted that the preset minimum stroke of the tensioning and closing cylinder 40 is greater than zero. The provision of the pads in this exemplary embodiment prevents the tensioning and closing cylinder 40 from locking or being damaged by excessive contraction during improper operation.

[0074] refer to Figure 2-Figure 4 As shown, in some embodiments, a measuring tower 80 is installed at each corner of the leveling frame 10, and a positioning device is provided on the top of each measuring tower 80, which is a GPS+prism all-in-one machine; it should be noted that the GPS+prism all-in-one machine includes a coaxially arranged GPS device and a 360° prism, which can meet the requirements of GPS and total station measurement and positioning methods at the same time in actual applications.

[0075] Furthermore, the underwater bed high-precision leveling operation method further includes a calibration step, which is performed in a dock and includes the following steps:

[0076] The hull of the bottom-seated leveling boat 70 is raised, and the leveling frame 10 is lowered so that the support assembly at the bottom is supported on the ground to simulate the actual situation of the leveling boat 70 when performing bed leveling operations. The height of the support assembly is adjusted to make the top surface of the leveling frame 10 level.

[0077] A total station is set up on the ground, prisms are placed at the four corners of the top surface of the leveling frame 10, and multiple prisms are placed in the length direction of the scraper 62. The total station is used to statically observe the prisms in the GPS+prism all-in-one machine at the top of the four measuring towers 80, the prisms at the four corners of the leveling frame 10, and the prisms on the scraper 62. The observation time for each observation point can be set to 5 minutes. After measuring multiple groups of data, the average value is calculated, thereby obtaining the relative position relationship between the GPS+prism all-in-one machine at the top of the four measuring towers 80 and the four corners of the leveling frame 10, and the relative position relationship between the leveling frame 10 and the GPS+prism all-in-one machine at the top of the four measuring towers 80. 0 relative elevation relationship between the four corners of the leveling frame 10 and the scraper 62, complete the calibration of the relative position relationship between the four positioning devices and the four corners of the leveling frame 10, and the calibration of the relative elevation relationship between the four corners of the leveling frame 10 and the scraper 62, and store them in the measurement and control system; thereby establishing an elevation transmission path among the positioning device, the leveling frame 10, and the scraper 62; in the subsequent base bed leveling operation, the elevation of the leveling frame 10 and the scraper 62 can be known through the measurement data of the positioning device, so as to accurately control the elevation of the leveling frame 10.

[0078] In the above exemplary embodiment, by installing measuring towers 80 at the four corners of the leveling frame 10 and positioning equipment on its top, accurate calibration of the relative relationship between the positioning equipment, the leveling frame 10 and the scraper 62 is achieved, which is beneficial to improving the leveling accuracy of the base bed.

[0079] refer to Figure 4 As shown, in some embodiments, in step S1, a hull measurement tower (not shown) is installed at the front and rear ends of the hull of the bottom-seated leveling ship 70, and a set of GPS+prism integrated machines is installed on the top of the hull measurement tower to measure and locate the leveling ship 70, so that the leveling ship 70 can be quickly and accurately positioned at the construction location; after the leveling frame 10 is lowered and seated on the bottom, the positioning devices on the top of the four measurement towers 80 thereon are all exposed outside the water and higher than the lifting winch on the hull; it can be understood that the lifting winch is connected to the leveling frame 10 through a lifting cable to lower or lift the leveling frame 10.

[0080] In steps S1 to S4, the elevation measurement data of the GPS at the top of the four measuring towers 80 are used, and combined with the relative position relationship between the four calibrated positioning devices and the four corners of the leveling frame 10, the elevation of the four corners of the leveling frame 10 is obtained; a total station is set up on the shore, and the prisms in the four positioning devices are observed by the total station to verify the elevation of the four corners of the leveling frame 10.

[0081] To further illustrate, the elevation data of the four corners of the leveling frame 10 can be taken as the average value of the elevation data within 5 minutes; if the difference between the measurement result and the preset elevation requirement does not exceed 5mm, it is considered that the elevation of the leveling frame 10 meets the preset elevation requirement; if the difference between the measurement result and the preset elevation requirement exceeds 5mm, the elevation of the leveling frame 10 needs to be adjusted.

[0082] In the above exemplary embodiment, the measuring towers 80 at the four corners of the leveling frame 10 and the positioning equipment on the top thereof can more accurately measure and position the leveling frame 10, thereby improving the elevation accuracy of the leveling frame 10 and further improving the leveling accuracy of the base bed.

[0083] refer to Figure 5 、 Figure 11 As shown, in some embodiments, the top surfaces of the two side frames 11 opposite to each other of the leveling frame 10 are provided with rails 13 extending along the length direction of the side frames 11, and the leveling platform trolley 60 drives the scraper 62 to move along the rails 13; the rails 13 include a plurality of rail segments 14 arranged in sequence along a straight line, and the rail segments 14 are installed on the leveling frame 10 by countersunk bolts; specifically, the length of the rail segments 14 does not exceed 1m, and a process gap is reserved between each adjacent rail segment 14.

[0084] Furthermore, the underwater bed high-precision leveling operation method further includes a track 13 debugging step, which is performed in the dock and includes the following steps:

[0085] The hull of the bottom-leveling boat 70 is raised, and the leveling frame 10 is lowered to the ground and leveled to simulate the state of the leveling frame 10 when the leveling boat 70 is performing a bed leveling operation;

[0086] Start the leveling vehicle 60 and move it along the track 13 from one end of the leveling frame 10 to the other end to simulate the situation when the leveling ship 70 is performing the bed leveling operation, that is, the leveling vehicle 60 applies pressure to the track 13;

[0087] A differential pressure static level 90 is used to measure the elevation difference of the track 13. Specifically, multiple monitoring points are set at intervals along the length of each track 13, with a differential pressure static level 90 placed at each monitoring point. A liquid storage tank 91 is provided on the outside of one end of the track 13. Each differential pressure static level 90 is connected to the bottom end of the liquid storage tank 91 via a liquid pipe and to the top end of the liquid storage tank 91 via a vent pipe. The differential pressure levels at multiple monitoring points can measure the elevation difference of the entire track 13.

[0088] Determine whether the height difference of the track 13 meets the preset height difference requirement; if the height difference of the track 13 does not meet the preset height difference requirement, then according to the measurement result of the height difference of the track 13, install at least one layer of gasket 15 between the corresponding track segment 14 and the leveling frame 10, and then start the whole platform vehicle 60 to move again, measure and judge the height difference of the track 13 again; specifically, the thickness of the gasket 15 can be 1mm~10mm, so as to make targeted and fine compensation for the height difference at different track segments 14, and ensure the overall smoothness of the entire track 13; if the height difference of the track 13 meets the preset height difference requirement, weld and fix the multiple layers of gaskets 15, and perform intermittent welding between the bottom gasket 15 and the leveling frame 10, and between the top gasket 15 and the track 13, respectively, to complete the debugging of the track 13.

[0089] The above-mentioned schematic embodiment realizes the segmented production of the track 13 by arranging multiple track segments 14 to form the entire track 13, thereby reducing the difficulty of producing the track 13. Compared with the currently commonly used entire long track 13, the track segment 14 is short in length, which can reduce the deformation caused by temperature changes. By adopting the whole platform vehicle 60 to travel to simulate the base bed leveling operation conditions and adding gaskets 15 at the bottom of the track segment 14 to adjust the height difference of the track 13, the influence of the deflection deformation of the track 13 on the height difference of the track 13 is greatly reduced, and the fine adjustment of the height difference of the track 13 is achieved. The debugged track 13 can have good elevation accuracy in the actual construction of the underwater base bed leveling operation, thereby ensuring the elevation accuracy of the scraper 62 when traveling, and further improving the base bed leveling accuracy.

[0090] In some embodiments, in the calibration step, the calibration of the relative position relationship between the four positioning devices and the four corners of the leveling frame 10, and the calibration of the relative elevation relationship between the four corners of the leveling frame 10 and the scraper 62 are carried out between 4 am and 6 am; in the track 13 debugging step, the measurement of the height difference of the track 13 is also carried out between 4 am and 6 am; because the land ambient temperature during this period is relatively stable and close to the underwater ambient temperature during the base bed leveling operation, the calibration work or the track 13 height difference measurement work can be made more accurate, which is conducive to improving the accuracy of the base bed leveling operation.

[0091] Through the description of multiple embodiments of the underwater bed high-precision leveling method of the present invention, it can be seen that the present invention has at least one or more of the following advantages:

[0092] 1) By arranging measuring towers 80 and positioning equipment at the four corners of the leveling frame 10, the leveling frame 10 can be measured and positioned more accurately. By performing an idle scraping operation on the leveling platform 60 after the leveling frame 10 is seated to eliminate instantaneous settlement, and by performing a height adjustment on the leveling frame 10 after each stone throwing and each scraping operation, it is ensured that the leveling frame 10 always has a good elevation accuracy during the entire subgrade leveling operation. The elevation accuracy of the leveling frame 10 can be controlled within ±5mm, thereby effectively improving the subgrade leveling accuracy.

[0093] 2) The provision of the cushion beam 20 significantly reduces the settlement of the leveled subgrade in contact with the cushion beam 20 and makes the settlement uniform, thereby improving the stability of the leveling frame 10 during the subgrade leveling operation. The addition of 5cm to 8cm stone and setting the average thickness of the subgrade leveling layer to 30mm are beneficial for reducing subgrade settlement and improving subgrade leveling accuracy. These measures can control subgrade settlement within 5mm.

[0094] 3) The multi-section design of track 13 and the adjustment of track 13 height difference reduce the difficulty of track 13 production and greatly reduce the impact of track 13 deflection on track 13 height difference. The fine adjustment of track 13 height difference can be achieved, and the track 13 elevation accuracy can be controlled within ±2mm, thereby effectively improving the bed leveling accuracy.

[0095] 4) Compared with the current manual leveling method with higher leveling accuracy, the underwater base bed high-precision leveling operation method of the present invention uses a bottom-mounted leveling vessel 70 to level the base bed, which can meet the base bed leveling operation needs at different water depths, reduce labor costs, improve the safety of leveling operations, increase the leveling efficiency by more than 20 times, increase the number of days available for water operations, and have significant economic benefits; moreover, the underwater base bed high-precision leveling operation method of the present invention significantly improves the underwater base bed leveling accuracy, and can meet the requirements of higher-precision base bed leveling operations. Practice has proved that the base bed leveling accuracy can reach ±2cm, and therefore it can be used in occasions where extremely high underwater base bed leveling accuracy is required, such as the construction of deep-water ports, the laying of submarine pipelines or cables, etc.

[0096] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0097] The above embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit the same. Although the present invention is described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present invention, which should all be included in the scope of the technical solution for protection of the present invention.

Claims

1. A method for high-precision leveling of an underwater bed, which uses a bottom-based leveling vessel to perform additional riprap fine leveling on a compacted bed to be leveled, characterized in that: The bottom-seated leveling boat includes a U-shaped leveling frame, a leveling platform trolley connected to the leveling frame, and the leveling platform trolley includes multiple silos and scrapers connected to the lower edges of all silos; a set of height-adjustable support assemblies are installed at the bottom of two side frames arranged opposite to each other on the leveling frame; the support assembly at the bottom of one side frame of the leveling frame includes a pad beam extending along the length direction of the side frame, and multiple jacking cylinders buried in the top surface of the pad beam, and the support assembly at the bottom of the other side frame includes multiple hydraulic legs, and the multiple jacking cylinders and multiple hydraulic legs jointly support the leveling frame in a liftable manner; the top surfaces of the two side frames arranged opposite to each other on the leveling frame are provided with tracks extending along the length direction of the side frames, and the leveling platform trolley drives the scraper to move along the tracks, and the tracks include multiple track segments arranged in sequence along a straight line, and the track segments are mounted on the leveling frame by bolts; The underwater bed high-precision leveling operation method includes a track debugging step, which is performed in a dock and includes the following steps: Lifting the hull of the bottom-standing leveling boat, lowering the leveling frame to the ground and leveling it; Starting the leveling platform vehicle and moving it along the track from one end of the leveling frame to the other end; A plurality of monitoring points are arranged at intervals along the length direction of each track, and a differential pressure static level is placed at each monitoring point. The differential pressure static levels at the plurality of monitoring points are used to measure the height difference of the track, and determine whether the height difference of the track meets the preset height difference requirement; if not, at least one layer of gasket is installed between the corresponding track segment and the leveling frame according to the measurement result of the track height difference, the whole platform vehicle is started to move again, and the track height difference is measured and determined again; if so, the multiple layers of gaskets are welded and fixed, and intermittent welding is performed between the bottom gasket and the leveling frame, and between the top gasket and the track, respectively, to complete the debugging of the track; The method for high-precision leveling of the underwater base bed further comprises the following steps: S1. After the bottom-supported leveling vessel arrives at the construction site, the leveling frame is lowered, and the cushion beam is supported on the leveled bed, and the plurality of hydraulic legs are supported on the compacted bed to be leveled; the height of each support assembly is adjusted to initially ensure that the elevations of the four corners of the leveling frame meet the preset elevation requirements; S2. Start the leveling platform vehicle and move it from one end of the leveling frame to the other end; check whether the elevations of the four corners of the leveling frame meet the preset elevation requirements; if not, adjust the heights of the support assemblies and execute step S2 again until the elevations of the four corners of the leveling frame meet the preset elevation requirements after the leveling platform vehicle moves; S3, throwing the preset amount of stone in the silo onto the compacted base bed to be leveled; checking the elevation of the four corners of the leveling frame at this time and adjusting it as needed to meet the preset elevation requirements; S4. Start the leveling platform vehicle to drive the scraper to move along the leveling frame for a preset leveling stroke to level the riprap area to form a base bed leveling layer; check the elevation of the four corners of the leveling frame at this time and adjust it as needed to meet the preset elevation requirements; S5. Repeat steps S3 to S4 until the bed leveling operation at the current ship position is completed; S6. Lift the leveling frame to remove the support assembly from the bed, move the bottom-seated leveling vessel to the next position, and execute steps S1 to S5 again until the preset length of underwater bed leveling operation is completed.

2. The method for high-precision leveling of underwater bed according to claim 1, characterized in that: In step S3, the particle size of the stone is 5 cm to 8 cm; in step S4, the average thickness of the base bed leveling layer is 30 cm.

3. The method for high-precision leveling of underwater bed according to claim 1, characterized in that: Wing spars are protrudingly provided on both sides of the lower width direction of the cushion beam, the bottom surface of the wing spars is coplanar with the bottom surface of the cushion beam, and the top surface of the wing spars is inclined upward toward the cushion beam.

4. The method for high-precision leveling of underwater bed according to claim 1, characterized in that: A plurality of first limit blocks and a plurality of second limit blocks that are flipped upward are respectively provided on both sides of the width direction of the top of the pad beam, and the bottom of the side frame corresponding to the pad beam is clamped between the first limit block and the second limit block; two groups of stop blocks that are relatively arranged are protruded in the length direction of the bottom of the side frame corresponding to the pad beam, and the two ends of the pad beam in the length direction are clamped between the two groups of stop blocks.

5. The method for high-precision leveling of underwater bed according to claim 1, characterized in that: There are five jacking cylinders, two of which are arranged at each end of the cushion beam in the longitudinal direction, and one jacking cylinder is arranged in the middle of the cushion beam in the longitudinal direction; there are two hydraulic support legs, which are respectively located at the two ends of the cushion beam in the longitudinal direction; In steps S1 to S4, when adjusting the elevation of the four corners of the leveling frame, first adjust the working stroke of the four jacking cylinders at both ends of the pad beam and the working stroke of the two hydraulic legs so that the elevation of the four corners of the leveling frame reaches the preset elevation requirements; then adjust the working stroke of the jacking cylinder in the middle of the pad beam so that the working stroke of the jacking cylinder is greater than the working stroke of the jacking cylinders at both ends of the pad beam, but the difference in working stroke does not exceed the elastic deformation of the middle of the pad beam relative to the two ends of the pad beam.

6. The method for high-precision leveling of underwater bed according to claim 1, characterized in that: A plurality of pulling and closing oil cylinders are also embedded in the top surface of the cushion beam, and the bottom and top of the pulling and closing oil cylinders are respectively connected to the cushion beam and the leveling frame; the top of the hydraulic support leg is connected to the leveling frame; In step S1, when the cushion beam has not yet been supported on the leveled base bed, the lifting cylinder is retracted in the cushion beam, and the pulling and closing cylinder is retracted to a preset minimum stroke so that the cushion beam is pressed against the leveling frame; after the cushion beam is supported on the leveled base bed, the pulling and closing cylinder is depressurized, and the lifting cylinder is extended to lift the leveling frame.

7. The underwater bed high-precision leveling method according to claim 1, characterized in that: A measuring tower is installed at each corner of the leveling frame. A positioning device is installed at the top of each measuring tower. The positioning device is a GPS + prism integrated device. The underwater bed high-precision leveling operation method also includes a calibration step, which is performed in the dock and includes the following steps: Lifting the hull of the bottom-seat leveling boat, lowering the leveling frame onto the ground and leveling it; A total station is set up on the ground, prisms are placed at the four corners of the top surface of the leveling frame, and multiple prisms are placed in the length direction of the scraper. The total station is used to calibrate the relative position relationship between the four positioning devices and the four corners of the leveling frame, and the relative elevation relationship between the four corners of the leveling frame and the scraper.

8. The method for high-precision leveling of underwater bed according to claim 7, characterized in that: In step S1, after the leveling frame is lowered, the positioning devices on the top of the measuring tower are exposed above the water surface; in steps S1 to S4, the elevation measurement data of the four positioning devices are used, and combined with the calibrated relative position relationship between the four positioning devices and the four corners of the leveling frame, the elevation of the four corners of the leveling frame is obtained; a total station is set up on the shore, and the four positioning devices are observed using the total station to verify the elevation of the four corners of the leveling frame.

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