Typical Structural Mechanical Performance Testing Device for Ships under Lateral Expansion by Sea Ice

Abstract

This invention discloses a test device for the typical structural mechanical properties of a ship hull under lateral compression by sea ice, comprising a base support system, a hydraulic servo loading system, and a plate frame base system. In the base support system, the bearing platform is fixed to the ground, and auxiliary support structures assist in fixing other components; the hydraulic servo loading system and sea ice clamps are fixed to the top surface of the bearing platform; in the plate frame base system, slide rails fixed to the bearing plate allow for adjustment and use of subsequent devices, and traction rings on the base carriage enable movement of the base carriage, simulating the test scenario of ice compression during straight-line ship navigation. Furthermore, by adjusting the angle of the slide rails, a ship-ice compression test environment under turning navigation conditions can be further constructed. This test device has a relatively simple layout, provides flexible control over the compression pattern between the ship and sea ice, and can effectively simulate the sea ice compression scenario during ship navigation, facilitating the conduct of local structural mechanical property tests under lateral compression.

Description

Technical Field

[0001] This invention relates to the technical field of ship and marine engineering testing equipment, specifically to a testing device for the typical structural mechanical properties of ship hulls under lateral sea ice compression. Background Technology

[0002] The Arctic region possesses abundant oil and gas resources. According to statistics, the Arctic region has petrochemical resources of 90 billion barrels of oil, 50 trillion cubic meters of natural gas, and 44 billion barrels of liquefied natural gas, accounting for approximately 13% of the world's recoverable oil and 30% of its natural gas. The Arctic Shipping Status Report released by the Arctic Marine Environment Conservation Working Group (PAME) shows that between 2013 and 2019, the total number of ships entering the Arctic region increased by 25%, and the total voyage distance increased by 75%; in 2019, the voyage distance of bulk carriers in the Arctic region increased by 160% compared to 2013.

[0003] Ships entering the Arctic face severe sea conditions and complex ice conditions. The main types of ice encountered by ships navigating in ice-covered areas are smooth ice, broken ice, and icebergs. The interaction between the ship and ice can be broadly categorized into two modes: compression and collision. The ice load on the ship's structure varies under these different modes, and factors such as course, speed, and ice size also have different effects on the ice load. When encountering smooth ice while navigating the Arctic shipping routes, the primary consideration is the compression load exerted by the sea ice on the ship's structure. The compression between the ship and the ice layer occurs in two main ways: side compression and turning compression. Compression is a continuous process, with the ship continuously subjected to the loads exerted by the ice.

[0004] Current research on ship-ice interaction loads mainly focuses on dynamic problems under ship-ice collisions, while quasi-static problems of ship-sea ice compression are relatively few. Ship-sea ice compression is mainly divided into ship side compression and ship turning compression. In the former, the ship and sea ice directly contact and compress each other, resulting in more intense compression, but the range of compression force changes is relatively small. In the latter, the ship compresses the sea ice during its movement, resulting in not only more intense compression but also a larger range of compression force changes.

[0005] Currently, there is little domestic research on ship-ice lateral compression tests and testing equipment. Therefore, there is a need for a testing device for the typical structural mechanical properties of ship hulls under lateral compression. Summary of the Invention

[0006] The purpose of this invention is to design the structural form of a test device for the mechanical properties of typical structures under lateral extrusion, and the required instruments and equipment, based on the requirements of ship-ice lateral extrusion tests in terms of scaled-down model size, applied load and method, and test measurement data, and in combination with the environmental conditions of the laboratory, so as to carry out ship-ice lateral extrusion tests.

[0007] The technical solution of the present invention:

[0008] A test apparatus for typical structural mechanical properties of ship hulls under lateral compression by sea ice, including a base support system, a hydraulic servo loading system, and a plate frame base system;

[0009] The base support system includes a bearing platform 1 and an auxiliary support structure 11; the hydraulic servo loading system includes a main frame structure, a loading device 5 and a sea ice clamp 6, the main frame structure includes columns 2, beams 3 and mounting plates 4; the plate frame base system includes a base carriage 8, slide rails 9 and a bearing base plate 13.

[0010] The column 2 has two members, the top of which is connected to both ends of the crossbeam 3, and the bottom end is fixed to the bearing platform 1 through the auxiliary support structure 11; the loading device 5 is installed on the crossbeam 3 through the mounting plate 4 and is located below the crossbeam 3; the sea ice clamp 6 is installed on the loading device 5; the loading device 5 is driven by an external servo drive device.

[0011] The supporting base plate 13 is installed horizontally or inclined on the supporting platform 1 and is located between two columns 2. The slide rail 9 is installed on the supporting base plate 13. The bottom of the base carriage 8 is provided with a pulley group 12. The base carriage 8 is installed on the slide rail 9. The front end of the base carriage 8 is provided with a traction ring 10. The test plate 7 to be tested is fixed on the upper surface of the base carriage 8. When the supporting base plate 13 is arranged horizontally, it simulates the linear motion of the hull. When it is arranged inclined, the inclination angle is set according to the test requirements to simulate the rotational motion of the hull.

[0012] The sea ice clamp 6 holds sea ice, and the loading device 5 drives the sea ice clamp 6 to move downward, thereby realizing the compression of the test plate 7 by the sea ice; a laser displacement sensor is set at the connection between the sea ice clamp 6 and the loading device 5 to measure the degree of deformation of the test plate 7 during the compression process; strain gauges are attached to the bottom of the test plate 7 to measure the strain change of the test plate 7 during the compression process.

[0013] Limiting blocks are provided at both ends of the slide rail 9.

[0014] The sea ice clamp 6 can be replaced according to the type of ice head required for the test.

[0015] The advantages of this invention are: this experimental device can simulate the test scenario of ship side compression by sea ice. The setup of this experimental device is relatively simple, and the control of the compression mode between the ship and sea ice is relatively flexible. It can effectively simulate the scenario of ship being compressed by sea ice during navigation, and can further simulate the test scenario of ship compression by sea ice rotation, thus solving the problem of the lack of experimental devices in the study of the compression mode between ships and sea ice. Attached Figure Description

[0016] Figure 1 This is an axial view of the device of the present invention;

[0017] Figure 2 This is a front view of the device of the present invention;

[0018] Figure 3 This is a partial view of the device of the present invention;

[0019] Figure 4 This is a schematic diagram illustrating the principle of base vehicle angle adjustment in the device of the present invention.

[0020] In the diagram: 1. Supporting platform, 2. Column, 3. Crossbeam, 4. Mounting plate, 5. Loading device, 6. Sea ice clamp, 7. Test plate, 8. Base car, 9. Slide rail, 10. Traction ring, 11. Auxiliary support structure, 12. Pulley block, 13. Supporting base plate. Detailed Implementation

[0021] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0022] like Figure 1 and Figure 2 As shown, the test device for the typical structural mechanical properties of a ship under lateral compression according to the present invention includes a base support system, a hydraulic servo loading system, and a plate frame base system; wherein, the base support system includes a bearing platform 1 and an auxiliary support structure 11; the hydraulic servo loading system includes a main frame structure composed of columns 2, beams 3 and mounting plates 4, a loading device 5 and a sea ice clamp 6; the plate frame base system includes a base carriage 8, a slide rail 9 and a bearing plate 13.

[0023] The main body of the hydraulic servo loading system consists of a column 2 and a crossbeam 3 welded and bolted together. In the middle of the crossbeam 3, a rectangular mounting plate 4 is bolted to the loading device 5. The loading device 5 is directly connected to the hydraulic drive device and other electrical equipment. The loading head of the loading device 5 is connected to the sea ice clamp 6, thus providing the extrusion load during the test. The sea ice clamp 6 can be replaced with different types of clamps, allowing for the selection of different ice head shapes, including square ice, disc ice, and wedge-shaped ice, to meet the needs of various ship lateral extrusion tests. The hydraulic servo loading system is fixed to the bearing platform 1 by an auxiliary support structure 11 to maintain the stability of the test device during the test; the auxiliary support structure 11 prevents the column 2 from tilting during the extrusion test, thus preventing damage to the test device.

[0024] like Figure 1 and Figure 3As shown, the base support system ensures the stability of the test device during the test. Multiple slide rails 9 are mainly composed of aluminum alloy rods and connected to the bearing base plate 13. Adjusting the angle of the slide rails 9 via the bearing base plate 13 allows for subsequent adjustments and use of the device. Multiple sets of limiting blocks can be installed at both ends of the slide rails 9 to ensure that the displacement of the base carriage 8 is limited within a certain range during the extrusion test. The base carriage 8 is constructed by welding and bolting aluminum alloy rods. Multiple sets of pulley groups 12 are symmetrically connected to the bottom of the base carriage 8 by welding and bolting to reduce the pressure of extrusion on individual pulleys, allowing the base carriage 8 to move along the slide rails 9. Different test plates 7 are fixed to the upper surface of the base carriage 8 by multiple sets of bolts, and can be disassembled and replaced. The preload of the bolts ensures that the boundaries of the test plates 7 remain straight during the test and restricts their inward sliding, thereby achieving the boundary condition of fixed support around the test plates 7.

[0025] When a ship is sailing in a straight line, it will come into contact with ice floes. In particular, the side of the ship, which is relatively fragile compared to the bow structure, is more susceptible to damage from sea ice loads. Multiple sets of traction rings 10 are set at the front end of the base car 8. The traction rings 10 can move the base car 8 along the slide rail 9, thereby simulating the scenario of sea ice squeezing the ship's side when the ship is sailing in a straight line. This allows for the conduct of tests on the sea ice squeezing the ship's side during straight-line navigation, and the establishment of a ship ice squeezing test scenario.

[0026] However, ships do not only navigate in a straight line; they may also turn. In this case, the ship not only has the speed of straight-line travel but also the angular velocity resulting from rudder turning. The ship will generate a velocity component towards the ice floe. At this point, the angle of the slide rail 9 can be adjusted by placing sandbags, frame support structures, or wooden pads under the bearing base plate 13 (e.g.,...). Figure 4 As shown in the figure, by adjusting the relative angle between the support base plate 13 and the support platform 1, the test scenario of ship ice rotation and extrusion can be simulated, thereby carrying out ship ice rotation and extrusion test.

[0027] A laser displacement sensor is further installed at the connection between the sea ice clamp 6 and the loading device 5. Since the hydraulic servo loading system is fixed to the bearing platform 1, the laser displacement sensor can effectively measure the deformation of the test plate 1. Strain gauges can be attached to the bottom of the test plate as needed to measure the strain change of the test plate during the compression process, which facilitates the better setting and adjustment of parameters such as the compression load in the sea ice compression test.

Claims

1. A test apparatus for typical structural mechanical properties of ship hulls under lateral compression from sea ice, characterized in that, The aforementioned test device for typical structural mechanical properties of hull under lateral sea ice compression includes a base support system, a hydraulic servo loading system, and a plate frame base system; The base support system includes a bearing platform (1) and an auxiliary support structure (11); the hydraulic servo loading system includes a main frame structure, a loading device (5) and a sea ice clamp (6); the main frame structure includes columns (2), beams (3) and mounting plates (4); the plate frame base system includes a base carriage (8), a slide rail (9) and a bearing base plate (13). The column (2) has two members, the top of which is connected to both ends of the crossbeam (3), and the bottom end is fixed to the bearing platform (1) by an auxiliary support structure (11); the loading device (5) is installed on the crossbeam (3) by a mounting plate (4) and is located below the crossbeam (3); the sea ice clamp (6) is installed on the loading device (5), and the loading device (5) is driven by an external servo drive device. The supporting base plate (13) is installed horizontally or inclined on the supporting platform (1) and located between two columns (2). The slide rail (9) is installed on the supporting base plate (13). The bottom of the base carriage (8) is provided with a pulley group (12). The base carriage (8) is installed on the slide rail (9). The front end of the base carriage (8) is provided with a traction ring (10). The test plate (7) to be tested is fixed on the upper surface of the base carriage (8). When the supporting base plate (13) is arranged horizontally, it simulates the linear motion of the ship. When it is arranged inclined, the inclination angle is set according to the test requirements to simulate the rotational motion of the ship. The sea ice clamp (6) is clamped with sea ice. The loading device (5) drives the sea ice clamp (6) to move downward, thereby realizing the compression of the test plate (7) by the sea ice. A laser displacement sensor is set at the connection between the sea ice clamp (6) and the loading device (5) to measure the degree of deformation of the test plate (7) during the compression process. Strain gauges are attached to the bottom of the test plate (7) to measure the strain change of the test plate (7) during the compression process.

2. The test apparatus for typical structural mechanical properties of ship hulls under lateral sea ice compression according to claim 1, characterized in that, Limiting blocks are provided at both ends of the slide rail (9).

3. The test apparatus for typical structural mechanical properties of ship hulls under lateral sea ice compression according to claim 1 or 2, characterized in that, The sea ice clamp (6) can be replaced according to the type of ice head required for the test.

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