A combined test device for damaging a plate-frame structure and its test method

Abstract

The present invention provides a combined test device for damaging a plate frame structure and a test method thereof, belonging to the field of ships. It solves the problems in the prior art that the cabin volume cannot be changed according to different working conditions and the explosion test cabin section model is difficult to reuse. It includes a lower deck, an upper deck, a plurality of fixed guide plates, a test plate frame and a fixed plate frame. Four cylindrical columns are provided between the lower deck and the upper deck, and the four cylindrical columns are respectively arranged at the four corners of the lower deck. A plurality of fixed guide plates are evenly distributed on the lower deck. The test plate frame and the fixed plate frame are both installed between the lower deck and the upper deck through the fixed guide plates. The fixed plate frame and the test plate frame form a sealed cabin structure with the lower deck and the upper deck. A charge support rod is provided at the central position of the sealed cabin, and the axis of the charge support rod passes through the center of the sealed cabin. It is mainly used for ship structure damage tests.

Description

Technical Field

[0001] The present invention belongs to the technical field of ship model tests, and particularly relates to a combined test device for damage of grillage structures and a test method thereof. Background Art

[0002] Surface ships are the main combat weapons in naval battles. When a ship is performing tasks at sea, it may be subjected to aerial strikes by weapons such as anti-ship missiles. Internal explosion in the cabin is an important part of the vulnerability research of ship targets. The grillage structure is an important part of the cabin of a surface ship. Studying the damage characteristics and damage modes of the grillage structure under the action of an internal explosion in the cabin, as well as the spatial distribution law of the explosion load of a multi-cabin structure, is of great significance for ship structure protection.

[0003] The existing Chinese invention patent with the publication number CN107655649A discloses an internal explosion test device for a cylindrical double-chamber structure. This device involves an internal explosion test device for a cylindrical double-chamber structure. This test device mainly aims at a cylindrical double-cabin structure, but the ship structure is a square multi-cabin structure, and it cannot accurately study the internal explosion damage characteristics and damage modes in the ship cabin. Moreover, it cannot change the existing cabin volume for different working conditions, resulting in low test efficiency and low reuse rate of the plates.

[0004] The Chinese invention patent with the publication number CN113654925A discloses a method for constructing a scaled-down model of a ship for an internal explosion of an anti-ship missile warhead. This method conducts explosion tests through a multi-cabin scaled-down model. Each explosion test will cause damage to the overall structure and render all the model materials ineffective. If a device can be used to only damage one or several grillage structures to be tested, while the wall surfaces of the other cabins that are not concerned do not deform during the explosion and can be reused, the test cost can be greatly saved. At the same time, such a device needs to have the characteristic of being able to change the volume, so as to realize the explosion damage test under various cabin volume conditions. Summary of the Invention

[0005] In view of this, the present invention aims to provide a combined test device for damage of grillage structures and a test method thereof, so as to solve the problems in the prior art that the cabin volume cannot be changed according to different working conditions and the model of the explosion test cabin section is difficult to reuse.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A combined test device for damaging a plate frame structure, comprising a lower deck, an upper deck, a plurality of fixed guide plates, a test plate frame and a fixed plate frame. Four cylindrical struts are arranged between the lower deck and the upper deck, and the four cylindrical struts are respectively arranged at the four corners of the lower deck. A plurality of fixed guide plates are evenly distributed on the lower deck. The test plate frame and the fixed plate frame are both installed between the lower deck and the upper deck through the fixed guide plates. The fixed plate frame and the test plate frame form a sealed chamber structure with the lower deck and the upper deck. A charge support rod is arranged at the center position of the sealed chamber, and the axis of the charge support rod passes through the center of the sealed chamber.

[0008] Furthermore, a plurality of sealed chamber structures are arranged on the lower deck.

[0009] Furthermore, fixed angle steels are arranged at the corners of the sealed chamber formed by the test plate frame and the fixed plate frame.

[0010] Furthermore, support plates are arranged at the bottoms on both sides of the fixed guide plates.

[0011] Furthermore, the fixed guide plates, the test plate frame and the fixed plate frame are all installed on the lower deck through bolts.

[0012] Furthermore, an observation window is arranged on the fixed plate frame. The observation window adopts explosion-proof glass. The fixed plate frame and the fixed guide plates are all made of high-strength steel.

[0013] Furthermore, both the upper deck and the lower deck are made of high-strength steel to ensure that no plastic deformation occurs under the action of explosion load. Uniform guide grooves are transversely and longitudinally opened on the end faces of the lower deck and the upper deck. The fixed guide plates are installed in the guide grooves, and triangular positioning bolt holes Ⅰ are evenly distributed on the fixed guide plates.

[0014] Furthermore, triangular positioning bolt holes Ⅱ are evenly distributed on the fixed angle steel. The fixed angle steel is connected to the test plate frame and the fixed plate frame through bolts.

[0015] Furthermore, the height of the charge support rod is half of the height of the cylindrical strut.

[0016] Furthermore, the calculation methods of the lower deck, the upper deck and the fixed plate frame. The structural design formulas of the lower deck and the upper deck are:

[0017]

[0018] Among them, M b is the ultimate bending moment of the plate girder. The plate girder is a structure composed of the stiffeners and the attached plates of the plate frame structure. D is the width of the attached plate, taken as the value in b and L b / 6, where b is the frame spacing and L b is the frame length, and P m$P_{max}$ is the peak overpressure of the explosion in the cabin, and $\beta$ is the safety factor;

[0019] The scaled distance from the measurement point to the explosion center is:

[0020]

[0021] where $Z$ is the scaled distance, $R$ is the distance from the measurement point to the explosion center in meters; $Q$ is the charge mass;

[0022] When $(0.05 \leq Z \leq 0.30)$, the formula for calculating the peak overpressure of the explosion in the cabin is:

[0023]

[0024] When $(0.30 \leq Z \leq 1.00)$, the formula for calculating the peak overpressure of the explosion in the cabin is:

[0025]

[0026] When $(1.00 \leq Z)$, the formula for calculating the peak overpressure of the explosion in the cabin is:

[0027]

[0028] where, $P$ s is the maximum overpressure in MPa;

[0029] The peak overpressure of the impulsive load acting on the wall surface is:

[0030] $P$ m $=\lambda P$ s

[0031] where $\lambda$ is the reflection coefficient of the air shock wave on the impacted surface, and the formula for $\lambda$ is:

[0032]

[0033] The design formula of the fixed plate frame structure is the same as that of the lower deck.

[0034] A test method for a combined test device for damage of a plate frame structure, which includes the following steps:

[0035] Step 1: Fix the fixed guide plate to the grooved part of the lower deck;

[0036] Step 2: Connect the lower deck and the upper deck through cylindrical columns;

[0037] Step 3: Connect the charge support rod to the center of the sealed explosion cabin and place the explosive;

[0038] Step 4: Install the test plate rack and the fixed plate rack in the middle of the fixed guide plate according to the design requirements respectively, and then connect them with bolts.

[0039] Step 5: Use fixed angle steel with bolts to fixedly connect the corners formed by the test plate rack and the fixed plate rack to form an explosion-proof sealed chamber structure.

[0040] Step 6: Place the high-speed camera outside the observation window.

[0041] Step 7: Detonate the explosive, and at the same time start the high-speed camera to record the damage process of the test plate rack in the sealed chamber, and complete one test.

[0042] Step 8: Replace the test plate rack, repeat Step 4 and Step 5, and conduct the next test.

[0043] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention provides a multi-chamber model that can be quickly assembled and has a variable volume, and a chamber explosion test device with low cost, high efficiency, and high reuse rate.

[0044] Fixed guide plates are arranged at uniform intervals on the upper and lower decks. According to the requirements of explosion tests in different chambers, different volume sealed multi-chamber structures can be quickly formed by bolts and special fixed angle steel. In different tests, only the test plate rack needs to be replaced, and other parts can be reused multiple times for the explosion test device.

[0045] When the present test device is used for explosion tests in chambers under the same working conditions, it is fixedly connected by bolts and special fixed angle steel, so that the test data is not affected by external interference factors such as material processing technology, effectively improving the accuracy of the test data; for explosion tests in chambers under different working conditions, the chamber volume can be quickly adjusted by bolts and special fixed angle steel, changing the spatial structure layout of the multi-chamber, and improving the test efficiency and the accuracy of the test data.

[0046] It is also possible to conduct only one test to study both the internal explosion damage characteristics of the plate rack structure and the spatial distribution law and damage mode of the multi-chamber explosion load. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0048] Figure 1 Schematic diagram of the combined test device for damage of the plate rack structure under multi-chamber internal explosion load of the present invention Figure I ;

[0049] Figure 2 Schematic diagram of the combined test device for damage of the plate rack structure under multi-chamber internal explosion load of the present inventionFigure II ;

[0050] Figure 3 Schematic diagram of the lower deck of the present invention;

[0051] Figure 4 Schematic diagram of the fixed guide plate of the present invention;

[0052] Figure 5 Schematic diagram of the fixed angle steel of the present invention.

[0053] 1 - Lower deck, 2 - Upper deck, 3 - Cylindrical pillar, 4 - Fixed guide plate, 5 - Support plate, 6 - Test plate rack, 7 - Fixed plate rack, 8 - Bolt, 9 - Fixed angle steel, 10 - Charge support rod, 11 - Observation window, Specific implementation mode

[0054] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0055] See Figures 1-5 Describing this embodiment, a combined test device for damaging a plate rack structure includes a lower deck 1, an upper deck 2, several fixed guide plates 4, a test plate rack 6 and a fixed plate rack 7. Four cylindrical pillars 3 are provided between the lower deck 1 and the upper deck 2, and the four cylindrical pillars 3 are respectively arranged at the four corners of the lower deck 1. Several fixed guide plates 4 are evenly distributed on the lower deck 1. The test plate rack 6 and the fixed plate rack 7 are both installed between the lower deck 1 and the upper deck 2 through the fixed guide plates 4. The fixed plate rack 7 and the test plate rack 6 form a sealed chamber structure with the lower deck 1 and the upper deck 2. A charge support rod 10 is provided at the center position of the sealed chamber. Fixed angle steels 9 are provided at the corners of the sealed chamber formed by the test plate rack 6 and the fixed plate rack 7. The fixed guide plates 4, the test plate rack 6 and the fixed plate rack 7 are all installed on the lower deck 1 through bolts 8. The fixed angle steels 9 are connected to the test plate rack 6 and the fixed plate rack 7 through bolts 8. An observation window 11 is provided on the fixed plate rack 7. The observation window 11 uses explosion-proof glass, and the strength of the explosion-proof glass is much greater than the strength of the test plate rack 6.

[0056] First, according to the requirements of explosion tests in different cabins, quickly form a sealed chamber structure with the required volume by surrounding the test plate rack 6 and the fixed plate rack 7 with bolts 8 and fixed angle steels 9. In different tests, only the different test plate racks 6 need to be replaced, and other parts can be reused. Therefore, the test device can quickly adjust the cabin volume according to different working conditions.

[0057] The sealed explosion chamber and the sealed observation chamber can be formed by the test plate rack 6 and the fixed plate rack 7. The damage process of the test plate rack 6 in the sealed explosion chamber can be observed through the observation window in the sealed observation chamber.

[0058] Multiple sealed explosion chambers can be formed to conduct in-chamber explosion tests in batches, study the vulnerability and different damage modes of the explosion load on the plate rack structure and the multi-chamber structure, study the spatial distribution law of the explosion load in the sealed multi-chamber structure, and solve the problems of long in-chamber explosion test cycle and low utilization rate of plates.

[0059] Furthermore, uniformly distributed guide grooves are transversely and longitudinally opened on the lower deck 1 and the upper deck 2 to ensure that both the test plate rack 6 and the fixed plate rack 7 can be clamped in. When conducting in-chamber explosion tests in different chamber structures and tests for different research purposes, the lower deck 1, the upper deck 2, and the cylindrical struts 3 can be reused. In this embodiment, it is an in-chamber explosion test for a two-chamber variable-volume chamber, and the TNT equivalent of the explosive is 10 kg.

[0060] According to the formula where L b = 5m, taking the strip width β = 1.5, substituting the TNT equivalent into the formula P m = λP s , and the lower deck 1 and the lower deck are 1.6m away from the explosion center, the peak overpressure p of the in-chamber explosion is obtained s = 1.29MPa, λ = 2.86, P m = 3.69MPa, substituting into the formula The minimum ultimate bending moment of the strip beam can be obtained:

[0061]

[0062] The lower deck 1 and the upper deck 2 are made of high-strength 945 steel, which is a 10×10m square plate with a wall thickness of 40mm. The specification of the fixed guide plate 4 is 20×300mm, and the transverse and longitudinal spacings are both 1m. The fixed guide plate 4 plays a role in fixing and connecting the test plate rack 6 and the fixed plate rack 7, equivalent to the stiffening rib between the lower deck 1 and the upper deck 2. Then, the ultimate bending moment of the strip beam of the lower deck 1 and the lower deck 2 is obtained as 10.6×10 6 N·m, which is greater than the designed ultimate bending moment of the strip beam.

[0063] According to the formula where L b = 2.6m, taking the strip width β = 1.5, substituting the TNT equivalent into the formula P m = λP s 、 and the fixed plate frame 7 is at a minimum distance of 1 m from the explosion center, and the peak overpressure p of the explosion inside the cabin is obtained s = 3.32 MPa, λ = 3.86, P m = 12.82 MPa. Substituting into the formula The minimum ultimate moment of the plate girder can be obtained as follows:

[0064]

[0065] The cylindrical strut 3, the fixed guide plate 4, the support plate 5, and the fixed plate frame 7 are all made of high-strength 945 steel with a wall thickness of 20 mm. Among them, the cylindrical strut 3 is 3.2 m high, the beam spacing of the fixed plate frame 7 is 0.65 m, and the size of the T-beam is Then the ultimate moment of the plate girder of the fixed plate frame 7 is obtained as 6.53×10 6 N·m, which is greater than the minimum design moment; the test plate frame 6 is made of Q235 steel with a wall thickness of 4 mm. For cabins with different volumes, the volume of the sealed cabin is adjusted by adjusting the position of the fixed plate frame 7 on different fixed guide plates 4.

[0066] Furthermore, support plates 5 are provided on both sides of the fixed guide plate 4 to reinforce the fixed guide plate 4, which plays a role in fixedly connecting the test plate frame 6 and the fixed plate frame 7. Triangular positioning bolt holes Ⅰ are evenly distributed on the fixed guide plate 4, which can fully ensure that the plate frames can form a sealed cabin. The fixed guide plate 4 and the support plate 5 of this test device can be reused multiple times.

[0067] Furthermore, both the test plate frame 6 and the fixed plate frame 7 can be clamped between the fixed guide plates 4, which is convenient for the test plate frame 6 to be replaced according to different working conditions and different test purposes, and the fixed plate frame 7 can be reused multiple times.

[0068] Furthermore, triangular positioning bolt holes Ⅱ are evenly distributed on the fixed angle steel 9. The fixed angle steel 9 is connected to both the test plate frame 6 and the fixed plate frame 7 through bolts 8. The fixed angle steel 9 is made of high-strength steel and its height can be determined according to the height of the cabin. The fixed angle steel 9 is connected to the test plate frame 6 and the fixed plate frame 7 through bolts. For the convenience of disassembly, it can be reused multiple times for different multi-cabin explosion tests.

[0069] Furthermore, both the cylindrical support column 3 and the charge support rod 10 are made of high-strength steel, and the heights of the cylindrical support column 3 and the charge support rod 10 can be fixed according to the height of the ship deck. The height of the charge support rod 10 is half of that of the cylindrical support column 3. The charge support rod 10 can always keep the explosive at the center position of the sealed compartment according to different compartment explosion tests, and the charge support rod 10 can also be reused for explosion tests in different compartments.

[0070] When the damage combined test device of the plate frame structure can be reused for tests with different research purposes, for tests in the same working condition batch, only the test plate frame 6 needs to be replaced according to the test requirements; when conducting tests in different working condition batches, only the test plate frame 6 and the compartment fixed plate frame 7 need to be replaced.

[0071] A test method for a damage combined test device of a plate frame structure includes the following steps:

[0072] Step 1: Fix and connect the fixed guide plate 4 at the grooved part of the lower deck 1;

[0073] Step 2: Connect the lower deck 1 and the upper deck 2 through the cylindrical support column 3;

[0074] Step 3: Connect the charge support rod 10 at the center of the sealed explosion compartment and place the explosive;

[0075] Step 4: Install the test plate frame 6 and the fixed plate frame 7 in the middle of the fixed guide plate 4 respectively according to the design requirements, and then connect them through the bolts 8;

[0076] Step 5: Use the fixed angle steel 9 to fixedly connect the corners formed by the test plate frame 6 and the fixed plate frame 7 through the bolts 8 to form an explosion sealed compartment structure;

[0077] Step 6: Place equipment such as a high-speed camera outside the observation window 11;

[0078] Step 7: Detonate the explosive, and at the same time start equipment such as a high-speed camera to record the damage process of the test plate frame 6 of the sealed compartment, and complete one test;

[0079] Step 8: Replace the test plate frame 6, and repeat Steps 4 and 5 to conduct the next test.

[0080] The embodiments of the present invention disclosed above are only used to help explain the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. According to the content of this specification, many modifications and changes can be made. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the present invention, so that those skilled in the relevant technical field can understand and utilize the present invention well.

Claims

1. A combined test device for damaging a plate frame structure, characterized in that: It includes a lower deck (1), an upper deck (2), several fixed guide plates (4), a test plate rack (6) and a fixed plate rack (7). There are four cylindrical struts (3) between the lower deck (1) and the upper deck (2), and the four cylindrical struts (3) are respectively arranged at the four corners of the lower deck (1). Several fixed guide plates (4) are evenly distributed on the lower deck (1). The test plate rack (6) and the fixed plate rack (7) are both installed between the lower deck (1) and the upper deck (2) through the fixed guide plates (4). The fixed plate rack (7) and the test plate rack (6) form a sealed chamber structure with the lower deck (1) and the upper deck (2). There is a charge support rod (10) at the center of the sealed chamber. The structural design formula of the lower deck (1) and the upper deck (2) is: Among them, M b is the ultimate bending moment of the plate girder, and the plate girder is a structure composed of the stiffeners and the attached plates of the grillage structure. D is the width of the attached plate, taken as the value of b and L b / 6, where b is the frame spacing and L b is the frame length, P m is the peak overpressure of the explosion in the cabin, and β is the safety factor; Where the scaled distance from the measurement point to the explosion center is: Where Z is the scaled distance, R is the distance from the measurement point to the explosion center, with the unit of m; Q is the charge amount; When (0.05 ≤ Z ≤ 0.30), the calculation formula for the peak overpressure of the explosion inside the chamber is: When (0.30 ≤ Z ≤ 1.00), the calculation formula for the peak overpressure of the explosion inside the chamber is: When (1.00 ≤ Z), the calculation formula for the peak overpressure of the explosion inside the chamber is: Among them, P s is the maximum overpressure, with the unit of Mpa; The peak overpressure of the impulsive load acting on the wall surface is: P m = λP s Where λ is the reflection coefficient of the air shock wave on the impacted surface, and the formula for λ is: The structural design formula of the fixed plate rack (7) is the same as that of the lower deck (1).

2. The combined test device for damaging a plate frame structure according to claim 1, characterized in that: There are multiple sealed chamber structures on the lower deck (1).

3. The combined test device for damaging a plate frame structure according to claim 1, characterized in that: Fixed angle steels (9) are provided at the corners of the sealed chamber formed by the test plate rack (6) and the fixed plate rack (7).

4. The combined test device for damaging a plate frame structure according to claim 1, characterized in that: Support plates (5) are provided at the bottoms on both sides of the fixed guide plate (4).

5. The combined test device for damaging a plate frame structure according to claim 1, characterized in that: The fixed guide plate (4), the test plate rack (6) and the fixed plate rack (7) are all installed on the lower deck (1) through bolts (8).

6. The combined test device for damaging a plate frame structure according to claim 5, characterized in that: An observation window (11) is provided on the fixed plate rack (7), and the observation window (11) uses explosion-proof glass.

7. The combined test device for damaging a plate frame structure according to claim 1, characterized in that: Uniform guide grooves are horizontally and vertically opened on the end faces of the lower deck (1) and the upper deck (2). The fixed guide plate (4) is installed in the guide grooves, and triangular positioning bolt holes Ⅰ are evenly distributed on the fixed guide plate (4).

8. The combined test device for damaging a plate frame structure according to claim 3, characterized in that: Triangular positioning bolt holes Ⅱ are evenly distributed on the fixed angle steel (9), and the fixed angle steel (9) is connected to the test plate rack (6) and the fixed plate rack (7) through bolts (8).

9. The test method of the combined test device for damaging a plate frame structure according to claim 1, characterized in that: It includes the following steps: Step 1: Fix and connect the fixed guide plate (4) to the grooved part of the lower deck (1); Step 2: Connect the lower deck (1) and the upper deck (2) through the cylindrical struts (3); Step 3: Connect the charge support rod (10) to the center of the sealed explosion chamber and place the explosive; Step 4: Install the test plate rack (6) and the fixed plate rack (7) respectively in the middle of the fixed guide plates (4) according to the design requirements, and then connect them through bolts (8); Step 5: Use bolts (8) to fixedly connect the corners formed by the test plate rack (6) and the fixed plate rack (7) with the fixed angle steel (9) to form an explosion-sealed chamber structure; Step 6: Place the high-speed camera outside the observation window (11); Step 7: Detonate the explosive, and at the same time start the high-speed camera to record the damage process of the test plate rack (6) of the sealed chamber, and complete one test; Step 8: Replace the test plate rack (6), repeat Step 4 and Step 5, and conduct the next test.

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