Test loading device and method for simulating non-uniform distribution characteristic of ice load

Abstract

The invention provides a test loading device and method for simulating an ice load non-uniform distribution characteristic, belongs to the technical field of structure tests, and is used for polar region equipment structure model test loading. According to the technical scheme, the test loading device comprises a counter-force constraint frame, a total pressure applying structure and a local high pressure applying structure. Wherein the counter-force constraint frame provides constraint counter-force for a test, and enough rigidity and strength are needed; the total pressure applying structure is fixed to the lower surface of the top of the counter-force constraint frame, total pressure is provided through a large jack, a total force measuring sensor measures the total pressure and is connected with a total pressure head and the large jack, and the space size of the total pressure head is designed according to the size of a high-pressure area. The local high-pressure applying structure is arranged in a total pressure head space, and loads and force are applied and measured through a small jack and a high-pressure area sensor. The device has the advantages of being convenient to install and easy and convenient to load, and the function of quantitatively applying non-uniform loads in the ice-resistant structure local model test can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of structural tests, and relates to a test loading device for quantitatively simulating the non-uniform distribution characteristics of ice loads for a polar equipment structural model, and a method for conducting tests using the device. Background Art

[0002] Polar equipment structures face serious threats from sea ice during operation, and ice loads are the main external loads on the structures. Due to the significant differences in their physical and mechanical properties caused by factors such as ice age and sea ice type, the fracture patterns of sea ice vary when the structure interacts with sea ice, resulting in significant random characteristics of ice loads. In both actual ship measurements and ice-water tank tests, it was found that the distribution of ice loads along the waterline of the structure has the characteristics of a high-pressure zone, that is, the pressure in the middle area where sea ice and the structure are squeezed is significantly greater than that in the surrounding area. In order to examine the impact of non-uniform ice loads on the design safety of polar equipment structures, corresponding model tests need to be carried out. At present, there is no effective loading device to apply quantitative non-uniform ice loads to the test models of polar equipment structures. The loading of the above test models is limited to uniform loading or qualitative non-uniform loading tests. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention provides a test loading device and method for simulating the non-uniform distribution characteristics of ice load. The test loading device can quantitatively simulate the non-uniform distribution of ice load on polar equipment structures along the waterline direction.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A test loading device for simulating the non-uniform distribution characteristics of ice loads comprises a reaction frame, a total pressure applying structure and a local high pressure applying structure.

[0006] The reaction frame provides a restraining reaction force for the test and is required to have sufficient rigidity and strength. It includes an upper top plate 1, a load-bearing column 2 and a lower bottom plate 11. The load-bearing column 2 connects the upper top plate 1 and the lower bottom plate 11, wherein the upper top plate 1 is used to connect the large jack 3, and the lower bottom plate 11 needs to ensure straightness for placing the test model.

[0007] The total pressure applying structure provides the total load for the test, including a large jack 3, a total pressure sensor 4 and a large pressure head 5. Among them, the large jack 3 is fixed on the lower surface of the upper top plate 1 and is connected to the hydraulic servo system 13, and the hydraulic servo system 13 controls the movement of the cylinder to apply the load. The total pressure sensor 4 is fixed to the lower end of the large jack 3 and is connected to the force measuring system 12 through a signal line to measure the total pressure of the test. The top of the large pressure head 5 is connected to the lower end of the total pressure sensor 4, and the bottom of the large pressure head 5 acts on the test model. The size of the large pressure head 5 is designed according to the size of the loading area and the high pressure area of ​​the test model. The width of the space reserved in the middle of the large pressure head 5 is the same as the width of the high pressure area, and the height must be sufficient to place the local high pressure applying structure. The large pressure head 5 needs to be arranged with an appropriate number of reinforcing ribs to ensure the strength and rigidity of the loading component.

[0008] The local high pressure applying structure provides non-uniform high pressure for the test, and includes an upper pad 6, a small jack 7, a middle pad 8, a high pressure sensor 9 and a lower pad 10. Among them, the upper pad 6, the middle pad 8 and the lower pad 10 function to transition and connect the loading device, and need to have sufficient rigidity, strength and straightness. The small jack 7 is fixed between the upper pad 6 and the middle pad 8 to provide local high pressure, which is controlled by the hydraulic servo system 13. The high pressure sensor 9 is fixed between the middle pad 8 and the lower pad 10, and is connected to the force measuring system 12 through a signal line to measure the magnitude of the high pressure. The upper end face of the upper pad 6 contacts the transverse reinforcing ribs in the large pressure head 5, and the lower end face of the lower pad 10 contacts the test model.

[0009] A test loading method for simulating the non-uniform distribution characteristics of ice loads, the steps are as follows:

[0010] Adjust the position of the test model so that the large pressure head 5 is aligned with the loading area of ​​the test model. The hydraulic servo system 13 controls the large jack 3 to apply the load at a uniform speed, and reads the reading of the total pressure sensor 4 through the force measuring system 12 until the required total load is reached. The local high pressure application structure controls the small jack 7 to apply the load at a uniform speed through the hydraulic servo system 13, and reads the reading of the high pressure sensor 9 through the force measuring system 12 until the required high pressure area load is reached. In the process of applying local high pressure, it is necessary to control the large jack 3 to fine-tune through the hydraulic servo system 13 to achieve the effect of keeping the total load unchanged.

[0011] The beneficial effects of the present invention are:

[0012] The present invention uses a hydraulic servo system to control a large pressure head to apply the total test load, controls a small pressure head located in the center of the large pressure head to apply the test high pressure area load, and equips the two pressure heads with force measuring devices respectively, so as to realize quantitative non-uniform load distribution. The test device is particularly suitable for quantitatively simulating the local non-uniform distribution characteristics of ice load, and is applied to the strength analysis model test of ice-resistant structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the present invention.

[0014] Figure 2 It is a schematic diagram of the total pressure application structure of the present invention.

[0015] Figure 3 It is a schematic diagram of the local high pressure application structure of the present invention.

[0016] Figure 4 It is a schematic diagram of non-uniform load distribution.

[0017] In the figure: 1 upper top plate; 2 load-bearing columns; 3 large jacks; 4 total pressure sensor; 5 large pressure head; 6 upper pad; 7 small jacks; 8 middle pad; 9 high pressure sensor; 10 lower pad; 11 lower bottom plate; 12 force measurement system; 13 hydraulic servo system. DETAILED DESCRIPTION

[0018] The structure, operation process, testing process and implementation examples of the present invention are further described below in conjunction with the accompanying drawings.

[0019] A test loading device for simulating the non-uniform distribution characteristics of ice loads comprises three parts: a reaction frame, a total pressure applying structure and a local high pressure applying structure.

[0020] The reaction frame provides a restraining reaction force for the test and requires sufficient rigidity and strength. It is composed of an upper top plate 1, a load-bearing column 2, and a lower bottom plate 12. The load-bearing column 2 connects the upper top plate 1 and the lower bottom plate 11. The upper top plate 1 needs to be arranged with threaded holes according to the size of the large jack 3 for connecting the large jack 3. The lower bottom plate 11 needs to ensure straightness for placing the test model.

[0021] The total pressure applying structure provides the total load for the test, and is composed of a large jack 3, a total pressure sensor 4, and a large pressure head 5. Among them, the large jack 3 is fixed on the lower surface of the upper top plate 1 and is connected to the hydraulic servo system 13, and the hydraulic servo system 13 controls the movement of the cylinder to apply the load. The total pressure sensor 4 is fixed to the lower end of the large jack 3 through the bolt hole, and is connected to the force measuring system 12 through the signal line to measure the total pressure of the test. The large pressure head 5 is connected to the lower end of the total pressure sensor 4 through the stud at the top. The bottom end of the large pressure head 5 acts on the test model, and the size of the large pressure head 5 is designed according to the size of the loading area and the high pressure area of ​​the test model. The width of the space reserved in the middle of the large pressure head 5 is the same as the width of the high pressure area, and the height must be sufficient to place the local high pressure applying structure. The large pressure head 5 needs to be arranged with an appropriate number of reinforcing ribs to ensure the strength and rigidity of the loading component. The material is high-strength steel.

[0022] The local high pressure application structure provides non-uniform high pressure for the test, and is composed of an upper pad 6, a small jack 7, a middle pad 8, a high pressure sensor 9 and a lower pad 10. Among them, the upper pad 6, the middle pad 8 and the lower pad 10 mainly function to transition and connect the loading device, and need to have sufficient rigidity, strength and straightness. The small jack 7 is fixed between the upper pad 6 and the middle pad 8 to provide local high pressure, which is controlled by the hydraulic servo system 13. The high pressure sensor 9 is fixed between the middle pad 8 and the lower pad 10, and is connected to the force measuring system 12 through a signal line to measure the magnitude of the high pressure. The upper end face of the upper pad 6 contacts the transverse reinforcing ribs in the large pressure head 5, and the lower end face of the lower pad 10 contacts the test model.

[0023] Figure 1 In the experiment, adjust the position of the test model so that the large pressure head 5 is Figure 4 The loading area of ​​the middle model is aligned. The hydraulic servo system 13 controls the large jack 3 to apply the load at a uniform speed, and reads the reading of the total pressure sensor 4 through the force measuring system 12 until the required total load is reached. The local high pressure application structure controls the small jack 7 to apply the load at a uniform speed through the hydraulic servo system 13, and reads the reading of the high pressure sensor 9 through the force measuring system 12 until the required high pressure area load is reached. In the process of applying local high pressure, it is necessary to control the large jack 3 to fine-tune through the hydraulic servo system 13 to achieve the effect of keeping the total load unchanged.

[0024] Figure 4 In the figure, the ice load is non-uniformly distributed along the waterline of polar equipment. Assuming that the length of the ice load action area is L, the width is W, the ice pressure in the high-pressure area is a times that in the low-pressure area, and the proportion of the high-pressure area is b. Then the load in the high-pressure area is:

[0025] F H =aP0×bL×W

[0026] It is necessary to apply structural loading through local high pressure. The load on the low pressure area is:

[0027] F L =P0×(1-b)L×W

[0028] The total load is:

[0029] F T =F H +F L =(1+ab-b)P0×L×W

[0030] It is necessary to apply structural loading through total pressure.

[0031] The above-described embodiments merely express the implementation methods of the present invention, but they cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A test loading device for simulating the non-uniform distribution characteristics of ice load, characterized in that: It includes a reaction frame, a total pressure applying structure and a local high pressure applying structure; The reaction frame comprises an upper top plate (1), a load-bearing column (2) and a lower bottom plate (12); the total pressure applying structure comprises a large jack (3), a total pressure sensor (4) and a large pressure head (5); and the local high pressure applying structure comprises an upper pad (6), a small jack (7), a middle pad (8), a high pressure sensor (9) and a lower pad (10).

2. A test loading device for simulating the non-uniform distribution characteristics of ice load according to claim 1, characterized in that: The reaction frame provides a restraining reaction force for the test and is required to have sufficient rigidity and strength; the load-bearing columns (2) connect the upper top plate (1) and the lower bottom plate (11), wherein the upper top plate (1) is used to connect the large jack (3), and the lower bottom plate (11) needs to ensure straightness for placing the test model.

3. A test loading device for simulating the non-uniform distribution characteristics of ice load according to claim 1, characterized in that: The total pressure applying structure provides a total load for the test. The large jack (3) is fixed on the lower surface of the upper top plate (1) and is connected to the hydraulic servo system (13). The hydraulic servo system (13) controls the movement of the oil cylinder to apply the load. The total pressure sensor (4) is fixed to the lower end of the large jack (3) and is connected to the force measuring system (12) through a signal line to measure the total pressure of the test. The top end of the large pressure head (5) is connected to the lower end of the total pressure sensor (4). The bottom end of the large pressure head (5) acts on the test model. The size of the large pressure head (5) is designed according to the size of the loading area and the high pressure area of ​​the test model. The width of the space reserved in the middle of the large pressure head (5) is the same as the width of the high pressure area, and the height is sufficient to place the local high pressure applying structure. The large pressure head (5) needs to be arranged with an appropriate number of reinforcing ribs to ensure the strength and rigidity of the loading component.

4. A test loading device for simulating the non-uniform distribution characteristics of ice load according to claim 1, characterized in that: The local high pressure applying structure provides non-uniform high pressure for the test, wherein the upper pad (6), the middle pad (8) and the lower pad (10) serve as transition and connection loading devices and need to have sufficient rigidity, strength and straightness; the small jack (7) is fixed between the upper pad (6) and the middle pad (8) to provide local high pressure and is controlled by a hydraulic servo system (13); the high pressure sensor (9) is fixed between the middle pad (8) and the lower pad (10) and is connected to the force measuring system (12) via a signal line to measure the magnitude of the high pressure; the upper end surface of the upper pad (6) contacts the transverse reinforcing ribs in the large pressure head (5), and the lower end surface of the lower pad (10) contacts the test model.

5. A test loading method for simulating the non-uniform distribution characteristics of ice load, characterized in that: The method is implemented by using a test loading device for simulating the non-uniform distribution characteristics of ice load as described in any one of claims 1 to 4, and the steps are as follows: The position of the test model is adjusted so that the large pressure head (5) is aligned with the loading area of ​​the test model; the hydraulic servo system (13) controls the large jack (3) to apply the load at a uniform speed, and reads the reading of the total pressure sensor (4) through the force measuring system (12) until the required total load is reached; the local high pressure application structure controls the small jack (7) to apply the load at a uniform speed through the hydraulic servo system (13), and reads the reading of the high pressure sensor (9) through the force measuring system (12) until the required high pressure area load is reached; during the local high pressure application process, it is necessary to control the large jack (3) through the hydraulic servo system (13) to fine-tune to achieve the effect of keeping the total load unchanged.

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