A method for side-rolling and loading a large steel box girder segment onto a ship

Abstract

The present invention relates to a method for side-rolling and loading large steel box girder segments onto a ship. By adopting a centralized control combination method, 2-3 12-axle modular vehicles are combined into one body and synchronized through the control of a power head PPU. The modular vehicle is moved under the steel box girder, and the steel box girder is lifted to the required height through a hydraulic lifting system. At an appropriate tide level, the large steel box girder segment is side-rolled onto the transport ship along a precast concrete ramp by using the modular vehicle. According to the differences in the forces on the wharf and the transport ship at each stage and the changes in the height difference of the deck surface during the operation process, the water level in the transport ship and the dock is adjusted to ensure the horizontalness of the deck surface. After the modular vehicle reaches the designated position, the lifting system is adjusted to lower the steel girder above the support pier on the deck surface. After being firmly supported, the modular vehicle drives away from the transport ship. Advantages: First, it solves the technical problem of side-loading large steel box girder segments and avoids the use of large-tonnage lifting facilities in the transfer site. Second, it can be used for the loading of various types of large steel box girder segments and has relatively low requirements for the loading wharf.

Description

Technical Field

[0001] The present invention relates to the construction of sideward roll-on loading of a large steel box girder segment with a length of 133.5 m and a weight of about 1750 t onto a ship. Background Art

[0002] CN102602712A, titled "A Method for Roll-on Loading of Steel Box Girder Segments onto a Ship", includes the following steps: 1. Transfer of the steel box girder segment: The steel box girder segment is transported to the wedge-shaped launching vehicle by a number of hydraulic shipyard trolleys; 2. Displacement and launching of the wedge-shaped launching vehicle and connection with the transport ship: The transport ship is positioned and connected to the wedge-shaped launching vehicle; 3. Transfer of the steel box girder segment onto the transport ship, and then the segment is fixed on the support pier of the transport ship, and the hydraulic shipyard trolley retreats to the wedge-shaped launching vehicle. The loading of the steel box girder segment onto the ship is completed. Its deficiencies are as follows: The steel box girder enters the transport ship along the length direction from the bow using tools such as wedge-shaped launching vehicles. Although the transportation operation is stable and the operation is safe and reliable. However, affected by the transportation and installation working conditions, for projects that require transfer or loading terminals that do not have longitudinal roll-on operation, after longitudinal roll-on, large-tonnage lifting equipment needs to be used in the transfer site to transfer to the hoisting unit. The construction investment and risks are relatively large, which is a major technical problem that has long existed in the industry. Summary of the Invention

[0003] Design objective: To avoid the deficiencies in the background art, a method for sideward roll-on loading of a steel box girder segment with a width of 20 m, a length of 133.5 m, and a weight of about 1750 t onto a ship is designed in the case of projects that do not have longitudinal roll-on operation at the transfer or loading terminal, as shown in Figure 1 .

[0004] Design scheme: In order to realize the sideward roll-on of a large steel box girder segment with a width of 20 m, a length of 133.5 m, and a weight of about 1750 t onto a transport ship, the present invention completes the method operation through hardware design, that is:

[0005] 1. In the hardware implementation of the method of the present invention: Sideward roll-on mainly uses a combination of modular vehicles. Through water level adjustment, the large steel box girder segment is slowly roll-on from the side to the transport ship. The main operation points include: design of the roll-on channel, design of the gangplank, adjustment of the water levels of the transport ship and the dock, etc. A supporting beam is arranged on the top surface of the transport ship deck. Since the bearing capacity of the corridor part along the dock shore is low, the supporting beam cannot contact the dock during the entire roll-on process. As a key component for carrying and subsequent transfer of the large segment, the supporting beam is subject to large forces, and its cross-sectional height is not less than 2.2 m. However, the lifting height of the beam transport vehicle is limited. Therefore, to ensure the smooth progress of the roll-on operation, according to the water level situation during construction, it is necessary to raise the height of both the transport ship deck and the dock quay simultaneously.

[0006] The present invention adopts a centralized control combination method, that is, 2-3 12-axis modular vehicles are combined into one body, and synchronization is achieved through the control of the power head PPU (the PPU controller is a prior art). The modular vehicle moves under the steel box girder, and the steel box girder is lifted to the required height through a hydraulic lifting system. At an appropriate tide level, the steel box girder is rolled onto the transport ship along the transport channel, and the transport ship and the water level in the dock are adjusted according to the force differences at each stage of the dock and the transport ship to ensure that the deck surface is horizontal. After the modular vehicle reaches the designated position, the lifting system is adjusted to lower the steel girder above the support pier (spur beam) on the deck surface. After firm support, the modular vehicle drives away from the transport ship, see Figure 3 . The key of the present invention lies in the design of the roll-on / roll-off channel, the synchronization control of the modular vehicle, and the water level adjustment. Among them, the design of the roll-on / roll-off channel is related to factors such as the water level in the dock, the draft of the ship, the lifting height of the modular vehicle, and the height of the support pier on the deck surface, and can be comprehensively considered through specific parameters. The synchronization of the modular vehicle is achieved through the centralized control combination method, and the water level adjustment is achieved by adopting tooling process measures according to factors such as the force on the transport ship at each stage, the change of the water level in the dock, and the water level difference in the cabin.

[0007] (1) Design of the roll-on / roll-off channel (see Figure 3 ): According to the tide level situation of the roll-on / roll-off dock, in order to ensure a certain safety distance between the spur beam and the upper surface of the ship dock and prevent the spur beam from contacting the ship dock during the roll-on / roll-off operation. It is necessary to build a precast concrete ramp with a width of 12 m, a length of about 20 m, and a slope of 4% at the transport channel, and the top of the slope is about 0.8 m higher than the ship dock surface.

[0008] In addition, aiming at the low bearing capacity of the front of the ship dock, the following measures need to be taken before the roll-on / roll-off operation: First, lay a steel plate with a thickness of 30 mm under the precast concrete block to disperse the concentrated load during the roll-on / roll-off process. In addition, the area under the transport beam lane at the front of the dock is reinforced with steel pipe piles, and 6 steel pipe piles (2 inside the corridor and 4 outside the corridor) are set under each lane. The height of the steel pipe pile is about 2.4 m, and an adjustment cushion plate is set on the top surface to ensure that the steel pipe pile is closely attached to the bottom surface of the ship dock concrete beam.

[0009] (2) Design of the gangplank (see Figure 4 ): Since the distance between the precast concrete ramp and the transport ship is relatively large, in order to ensure the smooth passage of the modular vehicle during the roll-on / roll-off operation of the large segment, a roll-on / roll-off gangplank is set between the barge and the dock. The roll-on / roll-off gangplank is about 6.5 m long, longitudinally divided into three sections, with inclined ends at both ends, and is connected to the middle section by a roller, which is beneficial to the passage of the modular vehicle and also beneficial to the release of the deformation of the steel gangplank during the roll-on / roll-off process. The steel gangplank is 1 m wide and is composed of multiple pieces in the transverse direction using pin joints, with a total width of about 12 m to meet the combined operation width of three modular vehicles.

[0010] (3)Water level adjustment: During the ro-ro operation, as the load on the transport ship increases, the height difference in water levels between the left and right compartments will cause the deck surface to tilt. Additionally, the overall sinking of the transport ship after bearing the load will also change the distance between the supporting beam and the dock top surface, as well as the slope of the gangplank. Therefore, water level adjustment during the operation is crucial. There are many factors affecting water level adjustment, including tidal level, adjustment plan, load adjustment capacity, and the traveling speed of the modular vehicle. It is necessary to jointly adjust the transport ship and the dock according to the operation plan for each stage of the ro-ro construction.

[0011] (4)Synchronization control of the modular vehicle: Using the power head PPU for control is an existing technology and will not be described here.

[0012] 2. Technical conditions of the present invention:

[0013] (1)The bearing capacity of the ro-ro terminal adopted in the present invention needs to meet the requirements of large-section ro-ro operations. Otherwise, the edge of the terminal needs to be reinforced.

[0014] (2)The water depth of the ro-ro terminal adopted in the present invention matches the draft depth of the transport ship, and the tidal level in the construction water area meets the requirements of ro-ro operations. The available tidal level duration is not less than 5 hours.

[0015] (3)When there is a difference in height between the deck height of the transport ship and the dock height during ro-ro operation water level, a ramp needs to be set for smooth transition. The length, width, and slope of the ro-ro passage meet the operation requirements of the modular vehicle.

[0016] (4)The transport ship has good load adjustment capacity, not less than 3000 cubic meters per hour, and the water level adjustment per hour is not less than 0.5 m.

[0017] (5)The modular vehicle has good load-bearing capacity and synchronization.

[0018] (6)Before the implementation of each project, it is necessary to refine the operation plan according to the technical characteristics of the large section, the tidal level in the construction water area, the dock working conditions, the parameters of the ship and the modular vehicle, etc.

[0019] Technical solution: A method for side ro-ro loading of large steel box girder segments onto a ship. Adopting a centralized control combination method, 2 - 3 modular vehicles with 12 axles are combined into one body and synchronized through the power head PPU control. (1) Move the modular vehicle 1 under the steel box girder 13 and lift the steel box girder to the required height through the hydraulic lifting system. (2) At an appropriate tidal level, use the modular vehicle to roll the large steel box girder segment onto the transport ship along the precast concrete ramp, and adjust the water levels of the transport ship and in the dock according to the stress differences between the dock and the transport ship at each stage and the height difference change of the deck surface during the operation to ensure the deck surface is horizontal. (3) After the modular vehicle reaches the designated position, adjust the lifting system, lower the steel girder above the support pier (supporting beam) on the deck surface. After firm support, the modular vehicle drives away from the transport ship.

[0020] Compared with the background technology, the present invention has the following advantages: First, it solves the technical problem of lateral loading of large steel box girder segments, avoiding the use of large-tonnage lifting facilities in the transfer yard; second, it is powerful and applicable, and can be used for the loading of various types of large steel box girder segments, and has strong reference significance for large steel truss girder segments; third, it adopts technical measures such as modular vehicle centralized control, precast ramp, steel gangplank, water level adjustment, etc., effectively ensuring the construction safety and operability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a plan layout diagram of the lateral ro-ro of large steel box girder segments.

[0022] Figure 2 It is a schematic diagram of the lateral ro-ro of large steel box girder segments, where: 1 - modular vehicle, 2 - precast concrete ramp, 3 - steel gangplank, 4 - supporting beam, 5 - ro-ro passage on the deck of the transport ship, 6 - dock terminal, 7 - dock, 8 - transport ship, 9 - steel pipe pile reinforcement, 10 - beam bottom cushion block, 11 - limiting device, 12 - steel wire rope, 13 - large steel box girder segment, 14 - roller, 15 - steel pier, 16 - backing plate.

[0023] Figure 3 It is a schematic diagram of the ramp setting in the dock ro-ro area.

[0024] Figure 4 It is a simplified diagram of the ro-ro gangplank.

[0025] Figure 5 It is a schematic diagram of the lateral ro-ro of the large segment onto the ship (the first stage).

[0026] Figure 6 It is a schematic diagram of the lateral ro-ro of the large segment onto the ship (the second stage).

[0027] Figure 7 It is a schematic diagram of the lateral ro-ro of the large segment onto the ship (the third stage).

[0028] Figure 8 It is a schematic diagram of the lateral ro-ro of the large segment onto the ship (the fourth stage).

[0029] Figure 9 It is a schematic diagram of the lateral ro-ro of the large segment onto the ship (the fifth stage).

[0030] Figure 10 It is a schematic diagram of the background technology. DETAILED DESCRIPTION OF THE INVENTION

[0031] Referring to the attached Figure 1 --10. The method for the lateral ro-ro loading of large steel box girder segments onto the ship is specifically described as follows:

[0032] The first stage: The modular vehicle enters the transport channel and slowly moves along the ramp surface to the front of the gangplank. At this time, all the weight is borne by the precast concrete ramp, as shown inFigure 5 .

[0033] Phase 2: The module car enters the ramp until the front end of the module car enters the ramp. The moving length is about 8.2m. At this time, the deck begins to be stressed. The barge rotates counterclockwise under the action of the torque. The water in the left water tank needs to be pumped to the right tank by a water pump to balance the torque. The load adjustment standard is 2m per moving distance. Figure 6 .

[0034] Phase 3: The module car continues to move forward until all the module cars enter the ship, with a moving length of about 14.1m. At this time, the deck is subjected to increasing force, and the barge rotates counterclockwise under the action of the torque. The water in the left water tank needs to be pumped to the right tank through a water pump, and the adjustment is made every 1m. At this time, as the weight of the steel beam and the module car is all borne by the ship, water needs to be injected through the dock door during the load adjustment to increase the water level in the dock and prevent the joist from touching the dock. Figure 7 .

[0035] Phase 4: The module car moves 7.7m and reaches the designated position on the deck. At this time, the weight of the steel beam remains unchanged, the distance is reduced, the torque generated is reduced, the water volume in the left warehouse is greater than the weight of the right warehouse, and the barge is in danger of turning clockwise and capsizing. The water volume in the right warehouse needs to be adjusted to balance the center of gravity of the barge in the left warehouse, and the adjustment is made every 1m. Figure 8 .

[0036] Stage 5:

[0037] (1) Beam lowering: a. Operate the transport vehicle group to transport the steel box beam to the designated loading position of the barge. Ensure that the longitudinal center line of the large section of the steel box beam is aligned with the parking position line drawn in advance on the deck of the barge through the longitudinal and lateral micro-adjustments of the vehicle group, and the error is controlled within ±20mm. b. Brake the entire vehicle and operate the SPMT module vehicle's own hydraulic lifting system to slowly descend. When the bottom of the steel beam is 50mm away from the top of the temporary pad, place a rubber pad on the temporary pad. c. Slowly descend again until the bottom of the steel beam contacts the rubber pad. The module vehicle continues to descend until the slideway beam bears about 80% of the weight of the large section (converted by the reading of the module vehicle support pressure gauge). Let it stand for 5 minutes. After checking and confirming that there are no abnormalities in the deck, slideway beam, steel box beam, etc., continue to descend until the weight of the steel box beam is entirely borne by the slideway beam.

[0038] (2) The module car drives off the deck: The weight of the 6 sets of module cars is about 300t. During the process of evacuating the dock, a large unbalanced moment will be generated, and the water tank needs to be adjusted. When the module car moves to the edge of the deck, the moving distance is 14.15m. At this time, the barge rotates counterclockwise. The center of gravity of the transport ship is balanced by adjusting the water volume from the left tank to the right tank, and the adjustment is made every 3m.

[0039] It should be understood that: Although the above embodiments have made a relatively detailed written description of the design concept of the present invention, these written descriptions are only simple written descriptions of the design concept of the present invention, rather than limitations on the design concept of the present invention. Any combination, addition or modification that does not exceed the design concept of the present invention falls within the protection scope of the present invention.

Claims

1. A method for side-rolling and loading a large steel box girder segment onto a ship, characterized in that: The centralized control combination mode is adopted to combine 2-3 12-axis modular vehicles into one, and the synchronization is achieved through the power head PPU control; the modular vehicle is moved to the bottom of the steel box girder, and the steel box girder is lifted to the required height through the hydraulic lifting system; at the appropriate tide level, the large section of the steel box girder is rolled onto the transport ship along the precast concrete ramp by the modular vehicle, and the water level of the transport ship and the dock is adjusted according to the force difference between the wharf and the transport ship at each stage and the height difference of the deck surface during the operation to ensure the level of the deck surface; after the modular vehicle reaches the designated position, the lifting system is adjusted to drop the steel beam above the deck support pier. After the support is firm, the modular vehicle drives away from the transport ship, which specifically includes: 1) The module vehicle enters the transport channel and moves slowly along the slope to the front of the steel ramp; 2) The module car moves along the steel gangway until the front end of the module car is completely inside the steel gangway. When the barge rotates counterclockwise under the action of the torque, the water in the water tank on the left side of the barge is pumped to the right tank through the water pump to balance the torque; 3) Module vehicle 1 continues to move forward and enters the ship. When the barge rotates counterclockwise under the action of torque, the water in the left water tank is pumped to the right tank through the water pump. When adjusting the load, water needs to be injected through the dock door to raise the water level in the dock and prevent the joist from touching the dock; 4) The module vehicle continues to move to the designated position on the deck. When the barge is in danger of turning clockwise and capsizing, the water volume in the right warehouse is adjusted to the left warehouse to balance the center of gravity of the barge; 5) Beam drop: a. Operate the transport vehicle group to transport the steel box girder to the designated loading position of the barge, and ensure that the longitudinal center line of the large section of the steel box girder is aligned with the parking position line drawn in advance on the deck of the barge through longitudinal and transverse micro-adjustments of the vehicle group; b. Brake the entire vehicle and operate the hydraulic lifting system of the SPMT module vehicle to slowly descend. When the bottom of the steel beam is close to the top of the temporary pad, place a rubber pad on the temporary pad; c. Descend slowly again until the bottom of the steel beam contacts the rubber pad. The module vehicle continues to descend until the slideway beam bears three-quarters of the weight of the large segment. Let it stand for a few minutes. After checking and confirming that there are no abnormalities in the deck, slideway beam, steel box beam, etc., continue to descend until the weight of the steel box beam is fully borne by the slideway beam. 6) Modular vehicles driving out of the deck: When the 6 groups of modular vehicles are evacuating the dock, a large unbalanced torque will be generated, and the water tank will be adjusted. When the modular vehicles move to the edge of the deck, the water volume in the left tank will be adjusted to the right tank to balance the center of gravity of the transport ship.

2. The method for side-rolling and loading a large steel box girder segment onto a ship according to claim 1, characterized in that: The supporting pier is a supporting beam.

3. The method for side-rolling and loading a large steel box girder segment onto a ship according to claim 1, characterized in that: After the modular vehicle moves more than 8.2 m along the steel gangway, that is, when the front end of the modular vehicle fully enters the steel gangway, the barge deck starts to bear force. Under the action of the moment, the barge rotates counterclockwise. At this time, the water in the left water tank of the barge is pumped to the right tank by a water pump to balance this moment. The water level in the barge cabin is adjusted every 2 m of the modular vehicle's movement until the modular vehicle fully enters the ship. At this time, the deck bears more and more force, and the barge rotates counterclockwise under the action of the moment. It is necessary to continue pumping the water in the left water tank to the right tank. Since the load-bearing of the barge changes greatly, the water level needs to be adjusted once every 1 m of the modular vehicle's movement at this time. As the weight of the steel beam and the modular vehicle is fully borne by the ship, while adjusting the load, it is necessary to inject water through the dock gate to raise the water level in the dock to prevent the slide beam from touching the shipyard. After the modular vehicle reaches the designated position on the deck, the weight of the steel beam remains unchanged, the distance decreases, and the generated moment decreases. The water volume in the left tank is greater than the weight in the right tank, and the barge has a risk of rotating clockwise and capsizing. At this time, the water volume in the right tank is adjusted to the left tank to balance the center of gravity of the barge. The water level needs to be adjusted once every 1 m of the modular vehicle's movement.

4. The method for side-rolling and loading large steel box girder segments onto a ship according to claim 1, wherein: Operate the transport vehicle group to transport the steel box girder to the designated loading position on the barge. Through the longitudinal and transverse micro-movement adjustment of the vehicle group, ensure that the longitudinal center line of the large section of the steel box girder is aligned with the pre-marked parking position on the barge deck, and the error is controlled within ±20 mm. Brake the whole vehicle, and operate the self-hydraulic lifting system of the SPMT modular vehicle to slowly lower. When the bottom of the steel beam is 50 mm away from the top of the temporary shim, place a rubber pad on the temporary shim. Slowly lower again until the bottom of the steel beam touches the rubber pad, and the modular vehicle continues to lower until the slide beam bears about 80% of the weight of the large section - that is, it is calculated through the reading of the support pressure gauge of the modular vehicle. At this time, the static time is not less than 5 minutes. After checking and confirming that there are no abnormalities in the deck, slide beam, steel box girder, etc., continue to lower until the weight of the steel box girder is fully borne by the slide beam.

5. The method for side-rolling and loading a large steel box girder segment onto a ship according to claim 1, characterized in that: The modular vehicle drives out of the deck: The weight of the 6 groups of modular vehicles is about 300 t. During the process of leaving the wharf, a large unbalanced moment will be generated, and it is necessary to adjust the load of the water tank. When the modular vehicle moves to the edge of the deck, the barge rotates counterclockwise. At this time, by adjusting the water volume in the left tank to the right tank, the center of gravity of the transport ship is balanced. At this time, the load-bearing change of the barge is small, and the water level is adjusted every 3 m.

6. The method for side-rolling and shipping large segments of steel box girders according to claim 1, wherein: Build a precast concrete slope with a width of 12 m, a length of about 20 m, and a slope of 4% at the transportation passage. The top of the slope is about 0.8 m higher than the shipyard surface.

7. The method for laterally ro-ro loading of large steel box girder segments onto a ship according to claim 1, characterized in that: The steel gangway is located between the barge and the wharf. The steel gangway is longitudinally divided into three sections, with inclined ends, and the two ends are connected to the middle section by rollers.

8. The method for side-rolling and loading a large steel box girder segment onto a ship according to claim 7, characterized in that: The width of the steel gangway meets the combined operation of three modular vehicles, and the steel gangway is transversely composed of multiple steel plates combined by pins.

9. The method for side-rolling and loading a large steel box girder segment onto a ship according to claim 1, characterized in that: Lay steel plates with a thickness of 30 mm under the precast blocks of the precast concrete slope. The area of the transport beam lane in front of the wharf is reinforced with steel pipe piles. Six steel pipe piles are set under each lane. Within the range of 2 - 3 m in height of the steel pipe piles, adjustment pads are set on the top surface to ensure that the steel pipe piles are closely attached to the bottom surface of the shipyard concrete beam.

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